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Background: Massage during labour is one form of intrapartum non-pharmacological pain relief but it is not known whether the frequency of practicing these massage techniques among couples during the antenatal period could enhance the effectiveness of intrapartum massage. This study was to evaluate the association between compliance of antenatal massage practice with intrapartum application and their impact on the use of analgesics during labour.Methods: This was a sub-analysis of a childbirth massage programme which was carried out in two public hospitals with total births of around 8000 per year. Data from women who were randomized to the massage group were further analysed. After attending the pre-birth training class on massage at 36 weeks gestation, couples would be encouraged to practice at home. Their compliance with massage at home was classified as good if they had practiced for at least 15 minutes for three or more days in a week, or as poor if the three-day threshold had not been reached. Application of intrapartum massage was quantified by the duration of practice divided by the total duration of the first stage of labour. Women's application of intrapartum massage were then divided into above and below median levels according to percentage of practice. Logistic regression was used to assess the use of epidural analgesia or pethidine, adjusted for duration of labour and gestational age when attending the massage class.Results: Among the 212 women included, 103 women (48.6%) achieved good home massage compliance. No significant difference in the maternal characteristics or birth outcomes was observed between the good and poor compliance groups. The intrapartum massage application (median 21.1%) was inversely associated with duration of first stage of labour and positively associated with better home massage practice compliance (p = 0.04). Lower use of pethidine or epidural analgesia (OR 0.33 95% CI 0.12, 0.90) was associated with above median intrapartum massage application but not antenatal massage compliance, adjusted for duration of first stage of labour.Conclusions: More frequent practice of massage techniques among couples during antenatal period could enhance the intrapartum massage application, which may reduce the use of pethidine and epidural analgesia.Trial Registration: (CCRBCTR) Unique Trial Number CUHK_ CCRB00525 . [ABSTRACT FROM AUTHOR]

The purpose of this retrospective cohort study is to determine if iron deficiency anaemia (IDA) is associated with increased atonic postpartum haemorrhage (PPH) following labour. Women with singleton pregnancy carried to 24 or more weeks gestation, who were delivered under our care from 1997 to 2019, constituted the study population. A diagnosis of IDA was based on the finding of haemoglobin <10 g/dL and serum ferritin <15 μg/L in the absence of haemoglobinopathies. Women with elective caesarean section were excluded. Maternal characteristics, use of oxytocin, labour outcome and occurrence of PPH were compared between women with and without a diagnosis of IDA. The 1032 women (0.86%) with IDA exhibited slightly but significantly different maternal characteristics and had significantly higher incidence of total (4.5% versus 3.2%, p = 0.024) and atonic PPH (3.1% versus 2.0%, p = 0.011) despite similar incidences of labour induction, augmentation, and instrumental and intrapartum caesarean delivery. Multivariate analysis with adjustment for the effects of age, body mass index, height, parity, abortion history, labour induction and augmentation, instrumental delivery and infant macrosomia demonstrated that IDA was independently associated with total PPH (adjusted relative risk, aRR: 1.455, 95% confidence ratio, CI: 1.040–2.034) and atonic PPH (aRR: 1.588, 95% CI: 1.067–2.364). Our results indicate that despite the low prevalence in our population, IDA was independently associated with atonic PPH, probably consequent to placental adaptive changes in the presence of IDA. The correction and prevention of IDA could be the most important measure in countering the rising global prevalence of atonic PPH. [ABSTRACT FROM AUTHOR]

Routine antenatal rubella serological testing is adopted in many countries. In a population covered by universal childhood rubella immunization for four decades, we have observed an association between pre-eclampsia with maternal rubella seronegativity among multiparous gravidae. This retrospective cohort study was further performed to elucidate the interaction between parity status and rubella seronegativity on obstetric outcome in singleton pregnancies carried to ≥ 24 weeks gestation managed from 1997 to 2019, with the data retrieved from a computerized database used for annual statistics and auditing. Of the 133,926 singleton pregnancies eligible for the study, the 13,320 (9.9%) rubella seronegative gravidae had higher mean booking weight and body mass index (BMI), but shorter height, and higher incidence of advanced age (≥ 35 years), high BMI, short stature, and lower incidence of nulliparas. Univariate analysis showed that adverse obstetric outcomes were more frequently found among the multiparas. On multivariate analysis, there was increased postdated (> 41 weeks) pregnancy irrespective of parity status, while nulliparas had reduced gestational hypertension (aRR 0.714, 95% CI 0.567–0.899) and gestational diabetes (aRR 0.850, 95% CI 0.762–0.950), and multiparas had increased pre-eclampsia (aRR 1.261, 95% CI 1.005–1.582), neonatal death (aRR 2.796, 95% CI 1.243–6.291), and perinatal death (aRR 2.123, 95% CI 1.257–3.587). In conclusion, in a population covered by universal childhood rubella immunization, antenatal rubella seronegativity is associated with increased pre-eclampsia and perinatal loss only in multiparas, suggesting that the rubella seronegativity in these women served as proxy for some form of altered immune response which increases adverse pregnancy outcome. [ABSTRACT FROM AUTHOR]

Background: We aimed to appraise the impact of the changing national childbirth policy since 2002, currently allowing two children per family, on obstetric workload in a regional referral center in China.Methods: In a retrospective cohort study, temporal changes were examined in relation with maternal demographics, incidence of women with high risk pregnancies and resource statistics in our hospital in managing singleton viable pregnancies (birth from 28 weeks gestational age onwards) for the period 2005-2017.Results: During this 13-year period, the number of singleton livebirths from 28 weeks gestational age onwards was 49,479. Annual numbers of births increased from 1,941 to 2005 to 5,777 in 2017. There were concomitant and significant increases in the incidence of multiparous women (10.6-50.8 %), of age ≥35 years (6.5-24.3 %), with prior caesarean Sec. (2.6-23.6 %), with ≥3 previous pregnancy terminations (1.0-4.9 %), with pre-gestational diabetes (0.2-0.9 %), and with chronic hypertension (0.2-1.2 %). There were associated increases in beds and staff complement and reduced average hospital stay. Nevertheless, while the workload of medical staff remained stable with increasing staff complement, that of midwives increased significantly as reflected by the total births: midwife ratio which increased from 194.1:1 to 320.9:1 (p < 0.001).Conclusions: In our hospital, progressively increasing numbers of annual births in combination with an increased incidence of women with high risk pregnancies took place following the revised national childbirth policy. Only the increase in medical and nursing, but not midwifery, staff was commensurate with workload. Remedial measures are urgently required before the anticipated progressive increase in care demand would overwhelm maternity care with potentially disastrous consequences. [ABSTRACT FROM AUTHOR]

Background: Chinese population has a high prevalence of chronic hepatitis B virus (HBV) infection, the impact of which on pregnancy outcome remains controversial. A single-center retrospective cohort study was performed in Kunming, a multi-ethnic city in south-western China to examine this issue.Methods: The singleton pregnancies delivering at ≥28 weeks gestation under our care in 2005-2017 constituted the study cohort. Maternal characteristics and pregnancy outcome were compared between mothers with and without seropositivity for hepatitis B surface antigen (HBsAg) determined at routine antenatal screening.Results: Among the 49,479 gravidae in the cohort, the 1624 (3.3%) HBsAg seropositive gravidae had a lower incidence of nulliparity (RR 0.963, 95% CI 0.935-0.992) and having received tertiary education (RR 0.829, 95% CI 0.784-0.827). There was no significant difference in the medical history, pregnancy complications, or labor or perinatal outcome, except that HBV carriers had significantly lower incidence of labor induction (RR 0.827, 95% CI 0.714-0.958) and of small-for-gestational age (SGA) infants (RR 0.854, 95% CI 0.734-0.994). On regression analysis, maternal HBV carriage was independently associated with spontaneous labor (aRR 1.231, 95% CI 1.044-1.451) and reduced SGA infants (aRR 0.842, 95% CI 0.712-0.997).Conclusions: Our 3.3% prevalence of maternal HBV infection was around the lower range determined in the Chinese population. The association with spontaneous labor and reduced SGA infants could have helped to promote the perpetuation of the infection through enhanced survival of the offspring infected at birth, thus explaining the high prevalence in the Chinese population. [ABSTRACT FROM AUTHOR]

Introduction: Chromosomal microarray analysis is recommended as the first‐tier test for the evaluation of fetuses with structural anomalies. This study aims to investigate the incremental diagnostic yield of chromosomal microarray over conventional karyotyping analysis in fetuses with anomalies restricted to one anatomic system and those with nonspecific anomalies detected by sonography. Material and methods: This is a retrospective cohort analysis of 749 fetuses undergoing prenatal diagnosis for abnormal ultrasound findings isolated to one anatomic system and normal karyotype, utilizing chromosomal microarray. Overall, 495 (66%) fetuses had anomalies confined to one anatomic system and 254 (34%) had other nonspecific anomalies including increased nuchal translucency (≥3.5 mm), cystic hygroma, intrauterine growth restriction and hydrops fetalis. Results: Fetuses with ultrasound anomalies restricted to one anatomic system had a 3.0% risk of carrying a pathogenic copy number variant; the risk varied dependent on the anatomic system affected. Fetuses with confined anomalies of the cardiac system had the highest diagnostic yield at 4.6%, but there were none in the urogenital system. Fetuses with nonspecific ultrasound anomalies had the highest diagnostic yield in fetuses with an intrauterine growth restriction at 5.9%. Overall, fetuses with a nonspecific ultrasound anomaly were affected with pathogenic copy number variants in 1.6% in the cases. Conclusions: The diagnostic yield of chromosomal microarray in fetuses with normal karyotype and ultrasound abnormality confined to a single anatomic system was highest if it involved cardiac defects or intrauterine growth restriction. This diagnostic yield ranges from 0% to 4.6% depending on the anatomic system involved. Chromosomal microarray has considerable diagnostic value in these pregnancies. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) infection is associated with many extrahepatic malignancies, but its association with and impact on ovarian cancer has not been examined. We therefore examined the prevalence of HBV infection among women with primary ovarian carcinoma in an endemic area, and whether this impacts the presentation and survival of these patients. In a retrospective study, we reviewed 523 patients presenting with primary ovarian cancer and known HBV status between 1 January 2006 and 31 December 2017. Patients were divided into HBV‐positive and negative groups for the comparison of the patient characteristics and presentation, including staging and histological types, and short term (2 years) mortality from ovarian cancer. Among the 10.1% (53/523) patients screened positive for HBV, more of them presented with advanced staging at FIGO stage 3 or above (OR 1.378, 95% CI 1.063‐1.787), although there were no significant differences in patient characteristics. Within 24 months from presentation, there were more deaths due to malignancy in the HBV‐positive group (73.3% vs 44.2%, OR 1.659, 95% CI 1.135‐2.425). On multivariate analysis after adjusting for nulliparity status, previous use of oestrogens, presence of metastases, histological type (epithelial or others) and grading (high grade or not), whether optimal debulking was performed, and chemotherapy, HBV infection was independently associated with increased death within 24 months of presentation (aOR 2.683, 95% CI 1.015‐7.091). In conclusion, the findings of this study suggested an adverse effect of chronic HBV infection on survival within two years of presentation in patients with primary ovarian cancer. [ABSTRACT FROM AUTHOR]

Chronic venous insufficiency (CVI) is a common disorder worldwide. Related pathophysiological mechanisms reportedly involve venous pooling and reduced venous return, leading to heaviness, aching, itchiness, tiredness, varicosities, pigmentation, and even lower limb ulceration. Approaches adopted to manage CVI at various stages of clinical‐etiology‐anatomy‐pathophysiology include compression therapy, pharmacological treatment, ultrasound treatment, surgery, electrical or wireless microcurrent stimulation, and pulsed electromagnetic treatment. Among these, polymer‐based therapeutic compression materials and wound dressings play increasingly key roles in treating all stages of CVI because of their unique physical, mechanical, chemical, and biological functions. However, the characteristics, working mechanisms, and effectiveness of these CVI treatment materials are not comprehensively understood. The present systematic review examines the structures, properties, types, and applications of various polymer‐based compression materials and wound dressings used in prophylaxis and treatment of CVI. Existing problems, limitations, and future trends of CVI treatment materials are also discussed. This review could contribute to the design and application of new functional polymer materials and dressings to enhance the efficiency of CVI treatments, thereby facilitating patients' self‐care ability and long‐term health improvement. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) can be found in ovarian tissues. This study compared HBV DNA levels in follicular fluid collected during oocyte retrieval with paired serum samples in HBV carriers after ovarian stimulation during IVF treatment for infertility. Sixty‐four HBV carrier women referred to the Assisted Reproductive Units of two Hong Kong hospitals were recruited. At oocyte retrieval, the follicular fluid aspirated from the first follicle was collected for study. In 22 women, the first follicular fluid sample from both ovaries was similarly collected and studied. These women were also tested for liver function test and HBeAg. In 28 (43.8%) women, HBV DNA was detected in follicular fluid and the level correlated with serum levels (Spearman's correlation P <.001). There was concordant detection of HBV DNA in both ovaries, and the levels were significantly correlated (Spearman's correlation P =.029). In 40% of women with FF HBV DNA, the follicular fluid:serum ratio was >1.0, suggesting stimulation of HBV replication. These women also had significantly different liver function test results. Increased HBV replication exists in 40% of women with HBV DNA detected in follicular undergoing ovarian stimulation during IVF treatment. [ABSTRACT FROM AUTHOR]

Aim: To describe changed epidemiological features of advanced maternal age (AMA) and to examine the effect of AMA on the risk for Cesarean section (CS) in a Chinese pregnant population. Methods: This retrospective single‐center cohort study investigated the changes of epidemiological features of AMA parturients with respect to the revised reproductive policy in China in 43 702 singleton deliveries with live birth at ≥28 weeks managed from January 2005 to December 2016. We also evaluated the pregnancy outcomes in different age groups and risk factors of CS with multivariate analysis. Results: In this 12‐year study period, the average maternal age increased from 28.5 to 30.2 years, and the proportion of AMA raised from 6.5% to 17.2%. AMA was significantly associated with increased risk of adverse pregnancy outcomes, and after adjustment for confounding factors, AMA remained a significant independent risk factor for CS. Furthermore, the effect of AMA in nulliparous women on the risk of CS was more significant than in multiparous women, while the history of previous CS (adjusted odds ratio 39.85) and interdelivery interval ≥10 years (adjusted odds ratio 1.52) also increased the risk of CS in multiparous women. Conclusion: AMA increased the risk of a number of adverse pregnancy outcomes, and was independently associated with increased risk for CS. The increasing number of AMA parturients with risk factors is likely to increase CS rate in China in the near future, thus it is imperative to reduce the rate of primary CS as a matter of policy. [ABSTRACT FROM AUTHOR]

It has been recognized that the cross-sectional curvatures of lower extremities directly influence pressure magnitudes and distributions exerted by compression garments. In the practice of compression therapy, higher peak pressures produced by compression shells occurred at anatomic sites with smaller radius of curvatures and led to side effects and discomfort perception. An effective and operational method to determine leg curvature properties in order to predict pressure performances is desirable to improve comfort and mechanical function of compression garment. By employing three-dimensional (3D) digital anthropometry and two-dimensional (2D) digital image simulation, the curvatures and radius of curvatures of a total of 300 cross-sectional slices involving 1200 anatomic sites along the lower limbs were determined onto the ten healthy female subjects when they were and were not wearing compression stockings. Based on the determined cross-sectional characteristics, the skin pressures were calculated using the circumference-based and the radius of curvature-based Laplace's equations, respectively, which were further validated against the experimental skin pressures measured by a PicoPress transducer. This study provided quantitative evidence in the exploration of the working mechanisms of uneven pressures produced by compression garments, and established a standardized method to determine cross-section-related curvature characteristics for pressure assessment and prediction, which will contribute to improving user compliance of compression garments in long-term wear. [ABSTRACT FROM AUTHOR]

Purpose: The relationship between maternal height and gestational hypertensive disorders was examined in a cohort of Chinese gravidae managed in 1997-2013 to clarify the association between short stature with preeclampsia (PE) and gestational hypertension (GH).Materials and Methods: Retrospective study of 87 290 gravidae categorized by their height into four quartile groups. The impact of short stature, defined as height in the lowest quartile, on incidence of PE and GH was studied in relation to the presence of risk factors. The independent role of short stature was determined by regression analysis.Results: The 25th, 50th, and 75th percentile values of height were 154 cm, 158 cm, and 161 cm respectively. The incidence of PE, but not GH, was inversely correlated with height (p = .025). Short stature altered the impact of parity status, advanced age, high body mass index, infant gender, and medical history, on incidence of PE but not GH. On regression analysis, short stature increased risk of PE (adjusted RR 1.134, 95%CI 1.005-1.279) but reduced GH (adjusted RR 0.836, 95%CI 0.718-0.974).Conclusions: Maternal short stature should be defined according to distribution in a specific ethnic group, and it exerts a significant but opposite effect on the incidence of PE versus GH. [ABSTRACT FROM AUTHOR]

The association between hypoechoic hepatomegaly in the third trimester and transient abnormal myelopoiesis (TAM) was reported previously in six fetuses with trisomy 21 (T21). We report a series of three cases of T21 in which hypoechoic liver (HL) was found in the second trimester but without evidence of TAM on both hematological and histological examination. We postulate that the hypo-echogenicity may be due to liver congestion secondary to hemodynamic disturbances seen in T21 fetuses. All three cases had negative first trimester Down syndrome screening and one case was detected solely because of the isolated finding of HL. HL per se may be associated with T21 and more positive cases are required to support this association. [ABSTRACT FROM AUTHOR]

Poor fit has become one of reasons for high non-compliance in the use of garments made of compression textiles in venous deficiency treatments. A novel methodology to categorize lower body shapes and sizes has been established via three-dimensional digital anthropometric technology in this study based on 208 Hong Kong subjects aged 40–60 years. Three new parameters were introduced to classify body shapes, namely the “A-angle” for assessing the “alignment” of lower extremities, the “cosine values of the key angle” at the turning point for below-knee shape determination, and “gradient” for above-knee shape categories. The mathematical simulation via the interpolation function was employed to explore the characteristics of shape variation trends with the involvement of dynamic interactions of both circumferences (Cir) and heights (Hei) of lower extremities. The clustering analysis quantitatively segmented the sample population into three stratified leg morphologies (i.e. diamond, inverted trapezoid, and balanced leg shapes) in terms of the determined anthropometric landmarks along the lower extremities, in which the Cir(s) of the brachial (cB1), calf (cC), and thigh (cF) exhibited most obvious differences among the clustered lower limbs. The created stratified shape-driven sizing system and methodologies further involved the body shape classifications into the Cir-based size categories to cater for diverse body morphologies in product size selection, thus improving dimensional fitness and accurate treatment using compression textiles in practice. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine the relationship between BMI and the incidence of rubella nonimmunity among pregnant women with regard to the World Health Organization categories.Methods: This was a retrospective cohort study of 117,063 eligible gravidas, managed between 1998 and 2015 in a university hospital of Hong Kong, China. BMI at antenatal booking was banded using the following World Health Organization definitions: < 18.5 kg/m2 , 18.5 to 24.9 kg/m2 , 25.0 to 29.9 kg/m2 , and ≥30.0 kg/m2 . Maternal rubella nonimmunity status by BMI was assessed. Incidence rates were also assessed after adjusting for maternal advanced age, short stature < 151 cm, mothers' birthplace, and postobstetric history covariates.Results: Rubella nonimmunity incidence increased as the BMI increased (P < 0.001). Gravidas with high BMI were more likely to be nonimmune if born in Hong Kong (odds ratio [OR], 1.234; 95% CI: 1.159-1.315; P < 0.001) compared with those born outside of Hong Kong (OR, 1.066; 95% CI: 0.997-1.141; P = 0.063). After adjusting for covariates, women with BMI ≥ 25 kg/m2 had 1.127 (P < 0.001; 95% CI: 1.074-1.182) greater odds of being nonimmune.Conclusions: High maternal BMI (≥ 25.0 kg/m2 ) is associated with reduced rubella immunity, an effect confined to gravidas with almost complete vaccine coverage in childhood. [ABSTRACT FROM AUTHOR]

Textile-based compression interventions (e.g. compression stockings and bandages), as an essential “source of pressure”, have impacted the effectiveness of pressure dosage delivery. The homogeneous structures of traditional compression shells generate highly uneven pressure distributions around leg geometrics in a passive mode, resulting in side effects and uncomfortable wearing perception. With this in mind, new heterogeneous compression sleeves with hybrid elastic properties were fabricated utilizing advanced three-dimensional seamless knitting technology and a unique laid-in structural design. PicoPress pressure assessment revealed in vivo that the developed heterogeneous compression shells with appropriate configurations for the lower limbs demonstrated the capability to proactively reshape skin pressures around leg cross-sections via calibrated proportions of segments with hybrid elastic moduli. The reduced anterior peak focal pressures and increased pressures at muscle-dominated posterior calves together provided a promising measure to enhance pressure function and user compliance in practice. The results will contribute to the development of a new generation of heterogeneous compression stockings with “bi-axial” pressure profiles for improved compression performance in extensive applications. [ABSTRACT FROM AUTHOR]

Problem It is unclear if the immunologic alterations induced by pregnancy could persist. Method of study Antenatal rubella sero-negativity was correlated with gravidity, abortions and parity in 112 083 gravidae managed during 1997-2015, with further analysis stratified for factors known to influence rubella serology. Results The 10.2% sero-negative gravidae had different characteristics, and the incidence showed significant difference and positive trend ( P<.001 for both) with gravidity, abortions and parity. The pattern remained consistent when analysis was stratified for advanced age, high body mass index and medical history, but was negated by hepatitis B virus infection except for abortions, and by high body mass index for parity. For gravidity 2-4, no difference in rubella sero-negativity was found between gravidae with all previous pregnancies ended in abortion vs delivery. Conclusion Prior pregnancies diminished rubella immunity in a dose-dependent manner, which may be a reflection of the cumulative effect of pregnancy-associated maternal immunologic alteration. [ABSTRACT FROM AUTHOR]

Objective: This study compared the incidence of rubella seronegativity among gravidae of 25 year-old and younger, between those born in Hong Kong after 1983 when the two-dose rubella vaccination was implemented, versus gravidae born before, to examine the impact of the two-dose regimen. Methods: In this retrospective cohort study, the incidence of antenatal rubella seronegativity in our parturients managed in1997-2015 was analysed by their age from ≤16 to 25 years, and the effect of year of birth was determined adjusting for confounding factors including teenage status, obstetric history, anthropometric factors, and health parameters including anaemia, thalassaemia trait and hepatitis B carrier status. Results: Among the 12743 gravidae, the 6103 gravidae born after 1983 had overall higher rubella seronegativity (9.1% versus 4.4%, OR 2.061, 95% CI 1.797–2.364), with significant difference (p = 0.006) and inverse correlation (p<0.001) with age, in contrast to the 6640 gravidae born in/before 1983 whom there was significant difference (p = 0.027) but a positive correlation (p = 0.008) with age. For each year of age, the former had significantly higher incidence of rubella seronegativity except for those of ≤16 years. Regression analysis confirmed that birth after 1983 was independently associated with rubella seronegativity (aOR 2.207, 95% CI 1.902–2.562). Conclusion: There was a significant trend between rubella seronegativity with age in young gravidae, but the pattern was opposite between gravidae born after versus in/before 1983, with the former having a higher incidence of seronegativity at all ages. Young women covered by the two-dose rubella immunisation programme have a paradoxically higher incidence of rubella seronegativity. [ABSTRACT FROM AUTHOR]

Problem To determine if maternal immune maladaptation associated with pre-eclampsia is reflected in the rubella immunity status. Method of study Incidence of pre-eclampsia was compared between rubella non-immune and immune gravidae carrying a singleton pregnancy beyond 24 weeks, taking into account maternal characteristics and reported risk factors for pre-eclampsia. Results The 9870 (10.4%) rubella non-immune gravidae among the 95 024 in the cohort exhibited no difference in incidence of underlying medical disorders, but they were slightly but significantly older, shorter, heavier, and had more pre-eclampsia ( OR 1.24, 95% CI 1.05-1.47) despite having fewer nulliparas. Regression analysis confirmed an overall association between rubella non-immunity with pre-eclampsia ( aOR 1.27, 95% CI 1.06-1.54), which was related to multiparas ( aOR 1.42, 95% CI 1.05-1.91) and carrying a male fetus ( aOR 1.37, 95% CI 1.06-1.78). Conclusion The association between rubella non-immunity and pre-eclampsia reflects immune maladaptation in multiparas and toward a male fetus. [ABSTRACT FROM AUTHOR]

Compression textiles as adjuvant physical interventions are increasingly applied for prophylaxis and treatment of chronic venous insufficiency (CVI), providing benefits of calibrated compression and controlled stretch. Pressure dosage delivered and mechanical properties (stiffness, elasticity and hysteresis) are determined by material nature, stitches structures, fabrication technology and delivery modes. Laplace’s Law and Pascal’s Law contribute to elaborate the static and dynamic working mechanisms behind the interaction between compression interventions and a biological body. However, there is still a lack of sufficient awareness on compression materials, and there is controversy regarding the best solution for clinical application of compression. This study integrates the views from physiology, pathophysiology, biomechanics, material science and textile engineering, to review and clarify physical–mechanical characteristics of compression materials, working mechanisms of textile-based compression interventions and their medical benefits in chronic venous insufficiency treatment. The aim is to enhance understanding of compression textiles applied in compression therapy, and to facilitate cooperation among multiple parties working in related supply chains, thus promoting textile-based compression interventions in chronic venous insufficiency treatment and growth of technical textiles applied in healthcare, medical and rehabilitation fields. [ABSTRACT FROM AUTHOR]

Problem As multiparas have high prevalence of chronic hepatitis B virus ( HBV) infection, we examined here the relationship between the number of pregnancies with HBV infection. Method of study Retrospective cohort study examining the prevalence of HBV infection by actual gravidity and parity in 104 242 gravidae managed during 1997-2013. Results Infection rate increased from 8.5% to 10.6% for G1 to G≥6 and from 8.8% to 10.0% for P0 to P≥3 ( P<.001). When stratified by parity, correlation with gravidity was maintained in the nulliparous gravidae. For the same gravidity, increasing parity was associated with higher rate of HBV infection for G2 and G3. Multiparas had higher HBV infection prevalence (all >10%) than nulliparas (<10%) for G2 to G≥4. Conclusion Prior pregnancies, especially successful ones, are associated with increased HBV infection in an endemic population, which could have enhanced reproduction and in the process facilitated its transmission to the following generations. [ABSTRACT FROM AUTHOR]

Problem The relationship between hepatitis B ( HBV) infection in infertile couples seeking in vitro fertilization ( IVF) treatment and infertility causes is unknown. Methods of study A total of 831 infertile couples attending our unit seeking IVF during January to December 2015 were recruited. Results HBV infection was found in 6.3% and 7.3% of female and male partners, respectively, and infection in one or both partners was associated with less primary infertility (44.2% vs 55.1%, P=.038). Infected female partners had increased tubal (69.2% vs 43.2%, P<.001) and uterine (13.7% vs 3.1%, P<.001) causes and reduced idiopathic infertility, while infected male partners were associated with increased tubal (62.3% vs 43.4%, P=.004) causes and reduced endometriosis (62.3% vs 73.9%, P=.050). Conclusion Our results suggest HBV infection in either partner was associated with tubal infertility. HBV infection in either partner probably increases the risk of pelvic infection in female partner through impaired immune response to sexually transmitted infections, with consequent tubal damage and infertility. [ABSTRACT FROM AUTHOR]

Pseudoamniotic band syndrome (PABS) is a rare iatrogenic complication that arises after invasive procedures in monochorionic twins. We report 3 cases of PABS, 2 after fetoscopic laser photocoagulation and 1 after bipolar cord coagulation. Two cases were detected antenatally by ultrasound; out of the two, one underwent successful fetoscopic release of amniotic band, which is the first report in twin pregnancy to our knowledge. In our centre, the incidence of PABS was found to be 2%. There were 25 cases of PABS reported previously, of which 12 cases with clinical details were reviewed together with our 3 cases. The fetal limbs were involved in all 15 cases, leading to constriction or amputation. The umbilical cord was involved in 2 cases, resulting in fetal death in one and pregnancy termination in the other. Antenatal detection of PABS is rare (27%; 4/15) as this requires a high index of suspicion. Serial postoperative targeted ultrasound surveillance of the fetal limbs and umbilical cord is necessary, particularly when features of septostomy or chorioamniotic membrane separation are found. Colour Doppler examination for the perfusion of the affected limb should be performed when PABS is detected. Fetoscopic release of amniotic band could salvage the fetal limb from amputation when impaired blood flow is detected. [ABSTRACT FROM AUTHOR]

Objective: To examine the seasonality of fetal trisomy 21 and its relationship with ambient air pollutants. Methods: The averaged incidence by month-of-conception of the 113 cases (2002-2009) in our registry was correlated with month of conception and monthly ambient levels of nitrogen oxides (NOx, NO and NO2), sulfur dioxide, carbon monoxide, and ozone as reported by the Hong Kong Environmental Protection Department at the month of, and four-week after, conception. Results: The incidence was highest in February (3.45/1000 births) and lowest in October (1.28/1000 births), and showed a significant difference ( p = 0.003) and positive correlation ( p = 0.003) from winter to autumn. It was also correlated with NO ( p = 0.017) and inversely with ozone ( p = 0.014) at conception. Conclusions: Seasonal variation in incidence of fetal trisomy 21 was correlated with ambient levels of nitric oxides and ozone. The role of environmental pollutants on fetal aneuploidy warrants further investigation. [ABSTRACT FROM AUTHOR]

Background: Newborns who have received hepatitis B immunization in 1980s are now young adults joining healthcare disciplines. The need for booster, pre- and post-booster checks becomes a practical question. Aims: The aim of this study is to refine the HBV vaccination policy for newly admitted students in the future. Methods: A prospective study on medical and nursing school entrants to evaluate hepatitis B serostatus and the response to booster doses among young adults. Findings: Among 212 students, 17–23-year-old, born after adoption of neonatal immunization, 2 (0.9%) were HBsAg positive, 40 (18.9%) were anti-HBs positive. At 1 month after a single-dose booster for anti-HBs-negative students, 14.5% had anti-HBs <10 mIU/mL, 29.0% and 56.5% were 10–100 and >100 mIU/mL, respectively. The anti-HBs levels were significantly higher for females than males (mean [SD]: 431 [418] vs. 246 [339] mIU/mL, P = 0.047). At 2–4 month after the third booster dose, 97.1% had anti-HBs >100 mIU/mL and 2.9% had 10–100 mIU/mL. Conclusions: Pre-booster check is still worthwhile to identify carriers among newly recruited healthcare workers born after adoption of neonatal immunization. A 3-dose booster, rather than a single dose, is required for the majority to achieve an anti-HBs level >100 mIU/mL, as memory immunity has declined in a substantial proportion of individuals. Cost-effectiveness of post-booster check for anti-HBs is low and should be further evaluated based on contextual specific utilization of results. [ABSTRACT FROM AUTHOR]

The prediction and management of fetal macrosomia remains an obstetric challenge. Significant maternal and neonatal complications can result from the birth of a macrosomic infant, and include prolonged labor, operative delivery, postpartum hemorrhage, perineal trauma, shoulder dystocia, birth trauma, chorioamnionitis, meconium aspiration, perinatal asphyxia, low Apgar scores, neonatal hypoglycemia, and perinatal mortality. This review article discusses these maternal and perinatal risks and the management of suspected macrosomia. [ABSTRACT FROM AUTHOR]

Objective: To determine the relationship between advanced maternal age (≥35 years) and incidence of postpartum hemorrhage (PPH) in singleton pregnancies managed over a 10-year period. Method: Retrospective cohort study comparing demographics, risk factors, complications, infant outcome, and incidence of PPH between parturients aged ≥35 and <35 years at delivery. Results: Parturients aged ≥35 years (12 686/64 886 or 19.6%) had significantly increased obstetric risk factors, complications, cesarean delivery, large-for-gestational age infants, and incidence of PPH, but no difference in the attributed cause of PPH such as uterine atony, retained placenta, genital lacerations, except for multiple factors. Multivariate analysis indicated that aging was actually associated with decreased PPH, the risk decreasing progressively from those aged 25-29 years to those aged ≥40 years compared with the 20-24 years group. Conclusions: Advanced maternal age only served as a surrogate factor for PPH due to the associated increased risk factors, obstetric complications and interventions. [ABSTRACT FROM AUTHOR]

Inlay yarn and laid-in stitches as important technical knitting elements have been commonly applied in the structural design and pressure control of compression textiles for certain healthcare and therapeutic purposes. In this study, complex weft laid-in stitches design changed the configurations of the studied elastic hoses and exerted significant impact on tension properties and pressure performance. The elastic hoses with laid-in structure involving more tuck loops generated lower tensile energy and elastic hysteresis in stretch. The resulting interfacial pressure thus generated showed a significantly increasing trend and better linear relationship with the raising of tension ratios. The hoses with longer floated inlay yarn increased the fabric extensibility but reduced tensile recovery. The geometric and morphologic deformations in stitches structure may impact the loop densities and compressive forces, thus varying the interfacial pressure generated during stretching. Laplace's law verified the interactive relations among pressure, tension, and curvature radius; however, its accuracy in the evaluation of pressure magnitudes of compression textiles needs to be further studied. [ABSTRACT FROM AUTHOR]

The averaged incidences of nonsyndromal/isolated cleft lip (CL), cleft palate (CP), and cleft lip with cleft palate (CLCP) by each month-of-conception, and managed in our hospital in from 2002 to 2009 were correlated with the reported levels of sunshine, ultraviolet radiation, and ambient nitrogen oxides (nitrogen oxide, nitrogen monoxide, and nitrogen dioxide), sulfur dioxide, and ozone, at the month of, and then at 4 and 8 weeks after, conception. There were 25, 12, and 22 cases each of CL, CP, and CLCP, respectively, totaling 59 cases (1.21 of 1000 births). On regression analysis, sunshine correlated inversely with the isolated CL at (P = .009) 4 weeks (P = .005) and 8 weeks (P = .008) postconception, and with CP (P = .009) and CLCP (P < .001) at 8 weeks postconception, while NOx correlated inversely with CL (P = .018) and NO with CLCP (P = .031), at 8 weeks postconception. Our results suggested that the interaction between sunshine and nitrogen oxides with other factors results in the reported seasonal variation in the incidence of isolated oral-facial clefts. [ABSTRACT FROM AUTHOR]

Objective To determine the effectiveness of cerclage pessary in the prevention of preterm birth in asymptomatic Chinese women with a short cervix at 20 to 24 weeks. Methods Low-risk women carrying singleton pregnancies were screened with transvaginal ultrasound, and those with a cervical length <25 mm at 20 to 24 weeks were recruited into a randomized controlled trial, comparing the prophylactic use of cerclage pessary with expectant management. The analysis was by intent-to-treat. The primary outcome measure was preterm delivery before 34 weeks. Results Among 4438 screened women, 203 women (4.6%) met the inclusion criteria and 108 (58%) consented for the study. A total of 53 and 55 women were allocated to pessary and control groups, respectively. There was no difference in background demographics, including the mean cervical length (19.6 mm versus 20.5 mm) and the mean gestational age at randomization (both 21.9 weeks). Delivery before 34 weeks occurred in 9.4% and 5.5% (p = 0.46) in the pessary and the control groups, respectively. No differences in major side effects were noted between the groups. Conclusion In our population, <5% had a cervical length of less than 25 mm at 20 to 24 weeks' gestation. The prophylactic use of cerclage pessary did not reduce the rate of preterm delivery before 34 weeks. [ABSTRACT FROM AUTHOR]

BACKGROUND The data in the literature suggests that Methimazole (MMI)/Carbimazole (CMZ) embryopathy is rare. This study examined the incidence of CMZ embryopathy in the Hong Kong Chinese population and the factors associated with its development. METHODS Of the 145 pregnant women with hyperthyroidism managed from 2008 to 2010, 29 (20%) had taken CMZ during pregnancy. The presence and details of birth defects, the dosage of CMZ, and the period of exposure during pregnancy were examined in these 29 pregnancies. All cases of CMZ embryopathy in the English literature were reviewed in the same way. RESULTS Of the 27 babies (93.1%) with known outcome, 3 had aplasia cutis and 1 had an omphalocele in addition, and 1 affected baby had a sibling with aplasia cutis and patent vitellointestinal duct. The incidence of CMZ embryopathy in our study group is 11.1%. Amongst the 21 cases of CMZ embryopathy in the literature, 85% were exposed to a CMZ dosage of ≥20 mg/day, and the minimum duration of exposure being 7 weeks from last menstrual period. The most common abnormality is ectodermal anomaly (62%), followed by oro-nasal anomaly (48%), facial dysmorphism (38%), gastrointestinal anomaly (33%) and abdominal wall defect (19%). There was no relationship between the type of abnormality and the dosage or duration of exposure to CMZ. CONCLUSIONS The incidence of CMZ embryopathy in our study group is 11.1%. Critical factors for its development are exposure to a CMZ dosage of ≥20 mg/day before 7 weeks of gestation. Genetic susceptibility may also play a role. Birth Defects Research (Part A) 97:225-229, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Objective: To elucidate the effect of hepatitis B virus (HBV) infection on breastfeeding uptake in Chinese mothers in an endemic region. Patients and Methods: A retrospective cohort study on 63 885 consecutive pregnant delivered between January 1997 and June 2008, were extracted from computerized database to examine the relationship between breastfeeding uptake and maternal HBV status, adjusted for demographic factors. Results: A total of 6593 (10.3%) women were hepatitis B surface antigen (HBsAg)-positive, with an annual prevalence of around 10%. In the study period, 29 869 (46.8%) practised breastfeeding, and its prevalence ranged from 35.4 to 54.8% with an increasing trend throughout the years ( p < 0.001). HBsAg-positive mothers had a significantly lower rate of breastfeeding (39.2 vs. 47.6% p < 0.001). Multiparas had higher incidence of HBV infection (10.9 vs. 9.8%, p < 0.001) and lower breastfeeding rate (42.2% versus 51.0%, p < 0.001) when compared with primiparas. Among those factors, maternal HBV infection had the strongest negative association with breastfeeding (adjusted odd ratio (aOR) = 0.726, 95% confidence interval (CI): 0.689-0.765). Conclusions: Our results suggested maternal HBV infection was one of the factors for the persistently low breastfeeding rate in Hong Kong over the past decades. To promote breastfeeding, it is necessary to generate definitive data on its safety regarding to mother-to-child transmission (MTCT) of HBV in order to allay the fear and anxiety in HBsAg-positive mothers. [ABSTRACT FROM AUTHOR]

This paper presents a novel solution for monitoring incontinence status through the design and development of the intelligent incontinence pants by the use of conductive yarns and incorporating advanced circular seamless knitting technology. The produced textile incorporates wire and electrodes by conductive yarn working with a siren system which can monitor, sense and alert the wearer and care provider on the incontinence status in real time so as to reduce the need for manual checking and minimize patient care workload. The engineered stitches, yarn materials, and unique seamless knitting techniques provide soft handling, special fabric mechanisms, and tactile comfort of the resulting product. The electrical resistance of knitted conductive yarn demonstrated a stable performance in wet processing. Fitting body trials were conducted to estimate product dimension and configuration. This study allows us to explore further the potential applications of conductive yarn and seamless knitting technology in bio-functional and intelligent healthcare products and solutions through integrating multidisciplinary knowledge and techniques. [ABSTRACT FROM AUTHOR]

Objective: To determine the obstetric outcome in teenage women managed in the recent decade with easily accessible health care provision. Methods: In a retrospective cohort study, maternal demographics, underlying medical conditions, obstetric complications, preterm birth, type of labor, mode of delivery, and perinatal mortality were compared between 1505 women aged ≤19 years (study group) with 10,320 women aged 20-24 years (comparison group), who were carrying singleton pregnancies beyond 24 weeks of gestation and managed in our hospital between January 1998 and June 2008. Results: The study and comparison groups accounted for 2.2% and 15.1% respectively of the total deliveries. Despite comparable health status and rates of other obstetric complications, teenage women was associated with birth <34 weeks (aOR 2.45, 95% CI 1.67-3.60), birth at 34-36 weeks (aOR 2.13, 95% CI 1.71-2.65), and reduced instrumental vaginal (aOR 0.62, 95% CI 0.50-0.77) and caesarean (aOR 0.79, 95% CI 0.64-0.97) delivery, without increase in perinatal mortality. Conclusions: Teenage women had increased preterm birth, despite improved health care provision, nutrition, and similar incidence of other obstetric complications, but the obstetric and perinatal outcome remained favorable. [ABSTRACT FROM AUTHOR]

Objective: This study was conducted to determine whether carrying a singleton male fetus increases the risk of preterm birth (PTB) in Chinese women. Methods: A retrospective cohort study was conducted on women with singleton pregnancies and delivered in our hospital. Maternal characteristics, pregnancy outcome, and incidence of PTB, were compared between women carrying a male versus a female fetus. The independent effect of a male fetus on PTB was examined with multiple logistic regression analysis adjusting for the other confounding factors identified. Results: There were significant differences in maternal and infant characteristics between women with a male versus a female fetus. Despite similar or lower incidences of complications and labor induction, women with a male fetus had increased birth <37 weeks (7.0% versus 6.2%, p < 0.001) and birth at 34-36 weeks (5.15% versus 4.4%, p < 0.001), but not for birth <34 weeks (2.0% versus 1.8%, p == 0.163). Regression analysis confirmed the association between male fetus with birth at 34-36 weeks (aOR 1.11, 95% CI 1.10-1.33) and spontaneous preterm labor (aOR 1.09, 95% CI 1.00-1.19). Conclusions: The results confirmed that carrying a male fetus is an independent risk factor for spontaneous preterm labor and PTB at 34-36 weeks gestation in southern Chinese women. [ABSTRACT FROM AUTHOR]

Objective: To determine if seasonal variation in the incidence of oral-facial clefts exists in the Hong Kong Chinese population. Methods: Cases of non-syndromal oral-facial clefts identified from the Prenatal Diagnostic Clinic database from 2002-2009, and total births from our departmental statistics during this period, were used to calculate the averaged month-of-conception incidence for overall cases and individual categories of clefts, including cleft lip (CL), cleft palate (CP), cleft lip with/without cleft palate (CL+/-CP), and cleft lip with cleft palate (CLP). Results: There were 59 eligible cases (1.21/1000 births), including 25 CL, 12 CP and 22 CLP cases. The peak incidence was in February (1.96/1000 births) and the lowest in September (0.67/1000 births). There was significant inverse correlation with the months from winter (December) to autumn (November) for all categories except for CP. When analysed by seasons, significant inverse correlation from winter to autumn was observed for all categories, and significant differences in incidence was demonstrated for CL+/-CP and CL. Conclusions: The seasonality in the incidence of oral-facial clefts found in this study suggested that environmental factors are probably involved, which would have accounted for the reported seasonal variations and geographical and racial differences in the incidence in the literature. [ABSTRACT FROM AUTHOR]

Objective. To assess the knowledge on commercial cord blood banking (CCBB) among pregnant women. Design. Cross-sectional survey. Setting. Antenatal clinics of two major public maternity units in Hong Kong. Population. Pregnant women. Methods. Self-administered questionnaire. Main outcome measures. The survey explored knowledge about the use of self-stored umbilical cord blood (UCB) stem cells and attitude towards CCBB. Results. Of the 2 000 women recruited, 1 866 (93.3%) completed the questionnaire. The majority (78.2%) had no idea that there was the chance of using self-stored stem cells. Moreover, most of the respondents were unclear about which diseases other than leukemia are amenable to treatment with UCB stem cells in general. Only 20.3% of women knew that stem cells are available from the Red Cross in case their children need hematopoietic cell transplantation. Conclusions. The results of this study revealed inadequate knowledge on UCB stem cell banking and its applications among most of our pregnant women. The government and clinicians should combine efforts to provide accurate information on utilization of UCB stem cells during antenatal care. [ABSTRACT FROM AUTHOR]

Objective. To elucidate the significance of isolated absent or hypoplastic nasal bone in the second trimester ultrasound scan. Methods. All cases of absent or hypoplastic nasal bone (length < 5th percentile) encountered during 2007--2009 were retrieved from database and all the ultrasound findings including structural abnormalities and soft markers for Down syndrome and fetal karyotype were reviewed. The cases were categorized into a study group with isolated absent or hypoplastic nasal bone and a comparison group with additional ultrasound findings. The incidence of Down syndrome confirmed by karyotyping was compared between the two groups. Results. Among 14 fetuses with absent or hypoplastic nasal bone identified, six (42.9%%) had Down syndrome and eight (57.1%%) were normal. All (100%%) of the six fetuses with isolated absent or hypoplastic nasal bone (Study Group) had normal karyotype, while six (75%%) of the other eight fetuses with additional ultrasound findings (Comparison Group) had Down syndrome ( p == 0.010). Conclusions. The use of isolated absent or hypoplastic nasal bone in the second trimester ultrasound scan for Down syndrome screening may not be effective. Amniocentesis, however, is indicated for fetuses with structural abnormality or additional soft marker which should be carefully searched by an experienced ultrasonographer. [ABSTRACT FROM AUTHOR]

Compression hosiery (CH) is one kind of mechanical therapeutic approach for the prophylaxis and treatment of venous disorders in the lower limbs. Their compression functional performance and comfort sensations are largely related to their material properties. The objective of this study was to comprehensively investigate the mechanical and surface properties of CH fabrics and their effects on corresponding skin pressure magnitudes in practical application. The mechanical testing of the material and skin pressure objective measurements applied to different kinds of CHs with four pressure levels were carried out using the Kawabata Standard Evaluation System and Multichannel skin pressure measuring system. This study shows that significant differences in material properties existed in CH fabrics with different pressure levels. Tensile energy (WT), tensile strain (EM), shearing stiffness (G) and bending rigidity (B) are key mechanical material indices, significantly correlative to skin pressure magnitudes; CHs fabrics with higher levels of pressure were rougher, stiffer and had less extensibility, but they had better dimensional stability. Significant differences in tensile, compression and surface properties existed between CHs fabrics in series A and those in B. The hosieries in series A produced more linear correlations between the key material indices and skin pressure magnitudes, which can be attributed to their fabrics having a smoother surface, greater elasticity, resilience and better dimensional stability. Moreover, proper surface properties of the material and hose design may enhance the pressure functional performance of compression hosiery products. [ABSTRACT FROM AUTHOR]

Aim: To clarify the relationship between maternal height and intrapartum operative delivery in women with singleton pregnancies. Methods: A retrospective cohort study was performed on Asian, mostly southern Chinese, women managed by our department in a 48-month period. They were categorized into four quartile groups according to their height ranking, with the 25th, 50th and 75th percentile values of height generated from the entire obstetric population. The labor and pregnancy outcomes of different quartile groups were compared. Results: A total of 13 606 pregnancies were recruited in the study cohort. The 25th, 50th and 75th percentile values of maternal height were 153 cm, 156 cm, and 160 cm, respectively, and the number of cases from the lowest to the highest quartile groups was 4153, 2698, 3445, and 3310, respectively. Significant differences were found in maternal weight, body mass index, incidences of multiparity and smokers, and birthweight and Apgar score at the first minute among the four quartiles. There was a significantly increasing incidence of cesarean delivery for mechanical reasons in spite of higher incidences of small-for-gestational age (SGA) and low birthweight (LBW) infants in decreasing quartiles. Regression analysis confirmed that the lower three quartile groups were associated with significantly increased cesarean delivery rates compared with the highest quartile group. Conclusion: Maternal height is inversely correlated with the risk of cesarean delivery for labor arrest. The effect of height acts as a continuum rather than in a dichotomous manner. The use of height percentile ranking may allow comparison between different populations on the effect on labor outcome. [ABSTRACT FROM AUTHOR]