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Background: Studies of early-term birth after demonstrated fetal lung maturity show that respiratory and other outcomes are worse with early-term birth (37 0 -38 6 weeks) even after demonstrated fetal lung maturity when compared with full-term birth (39 0 -40 6 weeks). However, these studies included medically indicated births and are therefore potentially limited by confounding by the indication for delivery. Thus, the increase in adverse outcomes might be due to the indication for early-term birth rather than the early-term birth itself., Objective: We examined the prevalence and risks of adverse neonatal outcomes associated with early-term birth after confirmed fetal lung maturity as compared with full-term birth in the absence of indications for early delivery., Study Design: This is a secondary analysis of an observational study of births to 115,502 women in 25 hospitals in the United States from 2008 through 2011. Singleton nonanomalous births at 37-40 weeks with no identifiable indication for delivery were included; early-term births after positive fetal lung maturity testing were compared with full-term births. The primary outcome was a composite of death, ventilator for ≥2 days, continuous positive airway pressure, proven sepsis, pneumonia or meningitis, treated hypoglycemia, hyperbilirubinemia (phototherapy), and 5-minute Apgar <7. Logistic regression and propensity score matching (both 1:1 and 1:2) were used., Results: In all, 48,137 births met inclusion criteria; the prevalence of fetal lung maturity testing in the absence of medical or obstetric indications for early delivery was 0.52% (n = 249). There were 180 (0.37%) early-term births after confirmed pulmonary maturity and 47,957 full-term births. Women in the former group were more likely to be non-Hispanic white, smoke, have received antenatal steroids, have induction, and have a cesarean. Risks of the composite (16.1% vs 5.4%; adjusted odds ratio, 3.2; 95% confidence interval, 2.1-4.8 from logistic regression) were more frequent with elective early-term birth. Propensity scores matching confirmed the increased primary composite in elective early-term births: adjusted odds ratios, 4.3 (95% confidence interval, 1.8-10.5) for 1:1 and 3.5 (95% confidence interval, 1.8-6.5) for 1:2 matching. Among components of the primary outcome, CPAP use and hyperbilirubinemia requiring phototherapy were significantly increased. Transient tachypnea of the newborn, neonatal intensive care unit admission, and prolonged neonatal intensive care unit stay (>2 days) were also increased with early-term birth., Conclusion: Even with confirmed pulmonary maturity, early-term birth in the absence of medical or obstetric indications is associated with worse neonatal respiratory and hepatic outcomes compared with full-term birth, suggesting relative immaturity of these organ systems in early-term births., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Objective: We sought to describe the prevalence of serious maternal complications following early preterm birth by gestational age (GA), delivery route, and type of cesarean incision., Study Design: Trained personnel abstracted data from maternal and neonatal charts for all deliveries on randomly selected days representing one third of deliveries across 25 US hospitals over 3 years (n = 115,502). All women delivering nonanomalous singletons between 23-33 weeks' gestation were included. Women were excluded for antepartum stillbirth and highly morbid conditions for which route of delivery would not likely impact morbidity including nonreassuring fetal status, cord prolapse, placenta previa, placenta accreta, placental abruption, and severe and unstable maternal conditions (cardiopulmonary collapse, acute respiratory distress syndrome, seizures). Serious maternal complications were defined as: hemorrhage (blood loss ≥1500 mL, blood transfusion, or hysterectomy for hemorrhage), infection (endometritis, wound dehiscence, or wound infection requiring antibiotics, reopening, or unexpected procedure), intensive care unit admission, or death. Delivery route was categorized as classic cesarean delivery (CCD), low transverse cesarean delivery (LTCD), low vertical cesarean delivery (LVCD), and vaginal delivery. Association of delivery route with complications was estimated using multivariable regression models yielding adjusted relative risks (aRR) controlling for maternal age, race, body mass index, hypertension, diabetes, preterm premature rupture of membranes, preterm labor, GA, and hospital of delivery., Results: Of 2659 women who met criteria for inclusion in this analysis, 8.6% of women experienced serious maternal complications. Complications were associated with GA and were highest between 23-27 weeks of gestation. The frequency of complications was associated with delivery route; compared with 3.5% of vaginal delivery, 23.0% of CCD (aRR, 3.54; 95% confidence interval (CI), 2.29-5.48), 12.1% of LTCD (aRR, 2.59; 95% CI, 1.77-3.77), and 10.3% of LVCD (aRR, 2.27; 95% CI, 0.68-7.55) experienced complications. There was no significant difference in complication rates between CCD and LTCD (aRR, 1.37; 95% CI, 0.95-1.97) or between CCD and LVCD (aRR, 1.56; 95% CI, 0.48-5.07)., Conclusion: The risk of maternal complications after early preterm delivery is substantial, particularly in women who undergo cesarean delivery. Obstetricians need to be prepared to manage potential hemorrhage, infection, and intensive care unit admission for early preterm births requiring cesarean delivery., (Published by Elsevier Inc.)

Objective: The objective of the study was to examine the rate of preterm birth in the United States using 2 different methods of gestational age assignment and determine which method more closely correlates with the known morbidities associated with preterm birth., Study Design: Using National Center for Health Statistics data from 2012 United States birth certificates, we computed the rate of preterm birth defined as a birth at 36 or fewer completed weeks with gestational age assigned using the obstetric estimate as specified in the revised birth certificate. This rate was then compared with the rate when gestational age is calculated using the last menstrual period alone. The rates of neonatal morbidities associated with preterm birth were examined for each method of assigning gestational age., Results: The rate of preterm birth was 9.7% when the obstetric estimate is used to calculate gestational age, which is significantly different from the rate of 11.5% when gestational age is calculated using the last menstrual period alone. In addition, the neonates identified as preterm by obstetric estimate were more likely to qualify as low birthweight (54% vs 42%; P < .001) and suffer morbidities such as need for assisted ventilation and surfactant use than those identified with the last menstrual period alone. That is to say obstetric estimate is more sensitive and specific for preterm birth by all available markers of prematurity., Conclusion: The preterm birth rate is 9.7% vs 11.5% and more closely correlates with adverse neonatal outcomes associated with preterm birth when gestational age is assigned using the obstetric estimate. This method of gestational age assignment is currently used by most industrialized nations and should be considered for future reporting of US outcomes., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: The objective of the study was to determine whether an individualized growth standard (IS) improves the identification of preterm small-for-gestational-age (SGA) neonates at risk of developing moderate/severe cerebral palsy (CP) or death., Study Design: This study was a secondary analysis of data from a randomized trial of MgSO4 for the prevention of CP or death among anticipated preterm births. Singleton nonanomalous liveborns delivered before 34 weeks' were classified as SGA (less than the 10th percentile for their gestational age) by a population standard (PS) or an IS (incorporating maternal age, height, weight, parity, race/ethnicity, and neonatal sex). The primary outcome was the prediction of moderate or severe CP or death by age 2 years., Results: Of 1588 eligible newborns, 143 (9.4%) experienced CP (n = 33) or death (n = 110). Forty-four (2.8%) were SGA by the PS and 364 (22.9%) by the IS. All PS-SGA newborns also were identified as IS-SGA. SGA newborns by either standard had a similarly increased risk of CP or death (PS: relative risk [RR], 2.4, 95% confidence interval [CI], 1.3-4.3 vs IS: RR, 1.8, 95% CI, 1.3-2.5, respectively). The similarity of RRs remained after stratification by the MgSO4 treatment group. The IS was more sensitive (36% vs 6%, P < .001) but less specific (78% vs 98%, P < .001) for CP or death. The receiver operating characteristic curve analysis revealed a statistically lower area under the curve for the PS, although the ability of either method to predict which neonates would subsequently develop CP or death was poor (PS: 0.55, 95% CI, 0.49-0.60 vs IS: 0.59, 95% CI, 0.54-0.64, P < .001)., Conclusion: An individualized SGA growth standard does not improve the association with, or prediction of, CP or death by age 2 years., (Copyright © 2013 Mosby, Inc. All rights reserved.)

Background: Because of increased rates of respiratory complications, elective cesarean delivery is discouraged before 39 weeks of gestation unless there is evidence of fetal lung maturity. We assessed associations between elective cesarean delivery at term (37 weeks of gestation or longer) but before 39 weeks of gestation and neonatal outcomes., Methods: We studied a cohort of consecutive patients undergoing repeat cesarean sections performed at 19 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network from 1999 through 2002. Women with viable singleton pregnancies delivered electively (i.e., before the onset of labor and without any recognized indications for delivery before 39 weeks of gestation) were included. The primary outcome was the composite of neonatal death and any of several adverse events, including respiratory complications, treated hypoglycemia, newborn sepsis, and admission to the neonatal intensive care unit (ICU)., Results: Of 24,077 repeat cesarean deliveries at term, 13,258 were performed electively; of these, 35.8% were performed before 39 completed weeks of gestation (6.3% at 37 weeks and 29.5% at 38 weeks) and 49.1% at 39 weeks of gestation. One neonatal death occurred. As compared with births at 39 weeks, births at 37 weeks and at 38 weeks were associated with an increased risk of the primary outcome (adjusted odds ratio for births at 37 weeks, 2.1; 95% confidence interval [CI], 1.7 to 2.5; adjusted odds ratio for births at 38 weeks, 1.5; 95% CI, 1.3 to 1.7; P for trend <0.001). The rates of adverse respiratory outcomes, mechanical ventilation, newborn sepsis, hypoglycemia, admission to the neonatal ICU, and hospitalization for 5 days or more were increased by a factor of 1.8 to 4.2 for births at 37 weeks and 1.3 to 2.1 for births at 38 weeks., Conclusions: Elective repeat cesarean delivery before 39 weeks of gestation is common and is associated with respiratory and other adverse neonatal outcomes., (2009 Massachusetts Medical Society)

Objective: To analyze neonatal mortality and morbidity rates at 34, 35, and 36 weeks of gestation compared with births at term over the past 18 years at our hospital and to estimate the magnitude of increased risk associated with late preterm births compared with births later in gestation., Methods: We performed a retrospective cohort study of births at our hospital over the past 18 years. The study included all liveborn singleton infants between 34 and 40 weeks of gestation and without anomalies that were delivered to women who received prenatal care in our hospital system. Neonatal outcomes for late preterm births were compared with those for infants delivered at 39 weeks., Results: Late preterm singleton live births constituted approximately 9% of all deliveries at our hospital and accounted for 76% of all preterm births. Late preterm neonatal mortality rates per 1,000 live births were 1.1, 1.5, and 0.5 at 34, 35, and 36 weeks, respectively, compared with 0.2 at 39 weeks (P<.001). Neonatal morbidity was significantly increased at 34, 35, and 36 weeks, including ventilator-treated respiratory distress, transient tachypnea, grades 1 or 2 intraventricular hemorrhage, sepsis work-ups, culture-proven sepsis, phototherapy for hyperbilirubinemia, and intubation in the delivery room. Approximately 80% of late preterm births were attributed to idiopathic preterm labor or ruptured membranes and 20% to obstetric complications., Conclusion: Late preterm births are common and associated with significantly increased neonatal mortality and morbidity compared with births at 39 weeks. Preterm labor was the most common cause (45%) for late preterm births., Level of Evidence: II.

Objective: Preterm birth occurs in 1 of 8 pregnancies and may result in significant morbidity and mortality. 17-alpha hydroxyprogesterone caproate (17-OHP caproate) has been found to be efficacious in reducing the risk of subsequent preterm delivery in women who have had a previous spontaneous preterm birth (sPTB). This analysis was undertaken to evaluate if 17-OHP caproate therapy works preferentially depending on the gestational age at previous spontaneous delivery. We hypothesized that treatment with 17-OHP caproate is more effective in prolonging pregnancy depending on the gestational age of the earliest previous preterm birth (20-27.9, 28-33.9 vs 34-36.9 weeks)., Study Design: This was a secondary analysis of 459 women with a previous sPTB enrolled in a randomized controlled trial evaluating 17-OHP caproate versus placebo. Effectiveness of 17-OHP caproate for pregnancy prolongation was evaluated based on gestational age at earliest previous delivery according to clinically relevant groupings (20-27.9, 28-33.9, and 34-36.9 weeks). Statistical analysis included the chi-square, Fisher exact, and Kruskal-Wallis tests, logistic regression, and survival analysis using proportional hazards., Results: Gestational age at earliest previous delivery was similar between women treated with 17-OHP caproate or placebo (P = .1). Women with earliest delivery at 20 to 27.9 weeks and at 28 to 33.9 weeks delivered at significantly more advanced gestational age if treated with 17-OHP caproate than with placebo (median 37.3 vs 35.4 weeks, P = .046 and 38.0 vs 36.7 weeks, P = .004, respectively) and were less likely to deliver <37 weeks (42% vs 63%, P = .026 and 34% vs 56%, P = .005, respectively). Those with earliest delivery at 34 to 36.9 weeks were not significantly different between 17-OHP caproate or control., Conclusion: 17-OHP caproate therapy given to prevent recurrent PTB is associated with a prolongation of pregnancy overall, and especially for women with a previous spontaneous PTB at <34 weeks.

Interleukin-6 (IL6) and suppurating placental inflammation are markers of neonatal sepsis. The purpose of this study was to define a relationship between IL6 and acute chorioamnionitis and funisitis of the placenta, and to compare IL6 levels in term and preterm neonates. Umbilical venous IL6 was measured in 137 term and 110 preterm neonates. Acute chorioamnionitis was graded as none, mild, moderate, severe, and necrotizing. Funisitis was graded as none, 1 vessel, 2 vessels, 3 vessels, or necrotizing. A 2-way analysis of variance with interaction was used to compare the IL6 levels. There was a stepwise progression of IL6 levels with increasing severity of acute chorioamnionitis and funisitis. Term neonates showed an IL6 elevation with mild acute chorioamnionitis and single-vessel vasculitis, which increased progressively until the inflammation became severe. In contrast, IL6 levels in preterm neonates did not increase significantly until severe acute chorioamnionitis or 3-vessel vasculitis was seen. Statistically significant differences in IL6 levels were seen in term versus preterm infants when the acute chorioamnionitis was mild or moderate or when the funisitis involved either 1 or 2 vessels (P < 0.05). The difference may be related to the relative immaturity of the preterm immune system, as has been demonstrated in vivo and in vitro. However, differences in management could be confounding factors. In conclusion, umbilical venous IL6 levels correlate with the severity of acute placental inflammation, with greater IL6 elevations in term infants compared to preterm infants until the inflammation becomes severe., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

Objective To assess whether neonatal morbidities evident by the time of hospital discharge are associated with subsequent cerebral palsy (CP) or death. Study Design This is a secondary analysis of data from a multicenter placebo-controlled trial of magnesium sulfate for the prevention of CP. The association between prespecified intermediate neonatal outcomes (n = 11) and demographic and clinical factors (n = 10) evident by the time of discharge among surviving infants (n = 1889) and the primary outcome of death or moderate/severe CP at age 2 (n = 73) was estimated, and a prediction model was created. Results Gestational age in weeks at delivery (odds ratio [OR]: 0.74, 95% confidence interval [CI]: 0.67–0.83), grade III or IV intraventricular hemorrhage (IVH) (OR: 5.3, CI: 2.1–13.1), periventricular leukomalacia (PVL) (OR: 46.4, CI: 20.6–104.6), and male gender (OR: 2.5, CI: 1.4–4.5) were associated with death or moderate/severe CP by age 2. Outcomes not significantly associated with the primary outcome included respiratory distress syndrome, bronchopulmonary dysplasia, seizure, necrotizing enterocolitis, neonatal hypotension, 5-minute Apgar score, sepsis, and retinopathy of prematurity. Using all patients, the receiver operating characteristic curve for the final prediction model had an area under the curve of 0.84 (CI: 0.78–0.89). Using these data, the risk of death or developing CP by age 2 can be calculated for individual surviving infants. Conclusion IVH and PVL were the only neonatal complications evident at discharge that contributed to an individual infant's risk of the long-term outcomes of death or CP by age 2. A model that includes these morbidities, gestational age at delivery, and gender is predictive of subsequent neurologic sequelae. Key Points Factors known at hospital discharge are identified which are independently associated with death or CP by age 2. A model was created and validated using these findings to counsel parents. The risk of death or CP can be calculated at the time of hospital discharge. [ABSTRACT FROM AUTHOR]

Objective  To evaluate sex-specific genetic susceptibility to adverse neurodevelopmental outcome (ANO, defined as cerebral palsy [CP], mental, or psychomotor delay) at risk for early preterm birth (EPTB, < 32 weeks). Study Design  Secondary case–control analysis of a trial of magnesium sulfate (MgSO 4) before anticipated EPTB for CP prevention. Cases are infants who died by the age of 1 year or developed ANO. Controls, matched by maternal race and infant sex, were neurodevelopmentally normal survivors. Neonatal DNA was evaluated for 80 polymorphisms in inflammation, coagulation, vasoregulation, excitotoxicity, and oxidative stress pathways using Taqman assays. The primary outcome for this analysis was sex-specific ANO susceptibility. Conditional logistic regression estimated each polymorphism's odds ratio (OR) by sex stratum, adjusting for gestational age, maternal education, and MgSO 4 -corticosteroid exposures. Holm–Bonferroni corrections, adjusting for multiple comparisons (p  < 7.3 × 10 −4), accounted for linkage disequilibrium between markers. Results  Analysis included 211 cases (134 males; 77 females) and 213 controls (130 males; 83 females). An interleukin-6 (IL6) polymorphism (rs2069840) was associated with ANO in females (OR: 2.6, 95% confidence interval [CI]: 1.5–4.7; p  = 0.001), but not in males (OR: 0.8, 95% CI: 0.5–1.2; p  = 0.33). The sex-specific effect difference was significant (p  = 7.0 × 10 −4) and was unaffected by MgSO 4 exposure. No other gene–sex associations were significant. Conclusion  An IL6 gene locus may confer susceptibility to ANO in females, but not males, after EPTB. [ABSTRACT FROM AUTHOR]

Objective To compare the risks of adverse maternal and neonatal outcomes associated with spontaneous (SPTB) versus indicated preterm births (IPTB). Methods A secondary analysis of a multicenter trial of vitamin C and E supplementation in healthy low-risk nulliparous women. Outcomes were compared between women with SPTB (due to spontaneous membrane rupture or labor) and those with IPTB (due to medical or obstetric complications). A primary maternal composite outcome included: death, pulmonary edema, blood transfusion, adult respiratory distress syndrome (RDS), cerebrovascular accident, acute tubular necrosis, disseminated intravascular coagulopathy, or liver rupture. A neonatal composite outcome included: neonatal death, RDS, grades III or IV intraventricular hemorrhage (IVH), sepsis, necrotizing enterocolitis (NEC), or retinopathy of prematurity. Results Of 9,867 women, 10.4% (N = 1,038) were PTBs; 32.7% (n = 340) IPTBs and 67.3% (n = 698) SPTBs. Compared with SPTB, the composite maternal outcome was more frequent in IPTB-4.4% versus 0.9% (adjusted odds ratio [aOR], 4.0; 95% confidence interval [CI], 1.4-11.8), as were blood transfusion and prolonged hospital stay (3.2 and 3.7 times, respectively). The frequency of composite neonatal outcome was higher in IPTBs (aOR, 1.8; 95% CI, 1.1-3.0), as were RDS (1.7 times), small for gestational age (SGA) < 5th percentile (7.9 times), and neonatal intensive care unit (NICU) admission (1.8 times). Conclusion Adverse maternal and neonatal outcomes were significantly more likely with IPTB than with SPTB. [ABSTRACT FROM AUTHOR]

Purpose: To examine prematurity-associated neonatal outcomes in early preterm infants with metabolic acidemia compared to those without such acidemia. Methods: We performed a retrospective cohort analysis to assess the impact of metabolic acidemia on prematurity-associated complications in a large cohort of singleton live-born infants with complete umbilical cord gas analyses delivered between 24 0/7 and 33 6/7 weeks. Metabolic acidemia was defined as an umbilical artery pH less than 7.0 plus a base deficit of 12mmol/L or greater. Outcomes were adjusted for gestational age using logistic regression. Results: Between 1 January 1988 and 31 December 2014, 6970 singleton early preterm infants were delivered at our hospital, of which 126 (1.8%) had metabolic acidemia. Neonatal mortality as well as prematurity-associated morbidities were significantly increased in the presence of metabolic acidemia. Included were ventilator requirement (73% versus 36%, p<0.001), grade 3/4 intraventricular hemorrhage (10% versus 4%, p<0.001), periventricular leukomalacia (5% versus 2%, p=0.036), and neonatal death (13% versus 4%, p<0.001). These significant findings persisted after adjustment for gestational age. Conclusion: Metabolic acidemia significantly increases the risks related to prematurity in infants delivered prior to 34 weeks' gestation. [ABSTRACT FROM AUTHOR]

Objective The objective of this study was to assess the relationship between first trimester cell-free total and fetal DNA in maternal plasma and the subsequent development of preeclampsia. Study Design Nested case-control study of patients enrolled in the Combined Antioxidant and Preeclampsia Prediction Studies prediction study of 175 women who did and 175 women who did not develop preeclampsia. The predictive values of cell-free total and fetal DNA and the subsequent development of preeclampsia were measured using receiver operating characteristic curves. Results Cell-free total DNA was higher in African American (median; 25-75%; 6.15; 0.14-28.73; p = 0.02) and Hispanic (4.95; 0.20-26.82; p = 0.037) compared with white women (2.33; 0.03-13.10). Levels of cell-free total DNA were also associated with maternal body mass index (BMI) (p = 0.02). Cell-free total DNA levels were similar between women who later developed preeclampsia (3.52; 0.11-25.3) and controls (3.74; 0.12-21.14, p = 0.96). Conclusion There is no significant difference in levels of cell-free total DNA in the first trimester in women who subsequently develop preeclampsia. Levels of cell-free total DNA in the first trimester are increased in African American and Hispanic compared with white women, and levels increase with increasing BMI. [ABSTRACT FROM AUTHOR]

Objective: This study was undertaken to compare success rates of vaginal birth after cesarean (VBAC) delivery, and uterine rupture as well as maternal/perinatal outcomes between women with preterm and term pregnancies undergoing trial of labor (TOL), and to compare maternal and neonatal morbidities in those women with preterm pregnancies undergoing a TOL versus repeat cesarean delivery without labor (RCD). Study design: Prospective 4-year observational study of women with a singleton gestation and a prior cesarean delivery at 19 academic centers. Clinical characteristics, maternal complications and VBAC delivery success for those with a preterm (240–366 weeks) TOL, preterm RCD and term TOL (≥37 weeks) were analyzed. Results: Among 3119 preterm pregnancies with prior cesarean delivery, 2338 (75%) underwent a TOL. 15,331 women undergoing TOL at term were also analyzed as a control group. TOL success rates for preterm and term pregnancies were similar (72.8% vs 73.3%, P = .64). Rates of uterine rupture (0.34% vs 0.74%, P = .03) and dehiscence (0.26% vs 0.67%, P = .02) were lower in preterm compared with term TOL. Thromboembolic disease, coagulopathy and transfusion were more common in women undergoing a preterm TOL than those at term. Among women undergoing a preterm TOL, rates of uterine dehiscence, coagulopathy, transfusion, and endometritis were similar to those having a preterm RCD. After controlling for gestational age at delivery and race, neonatal outcomes such as Neonatal Intensive Care Unit (N1CU) admission, intraventricular hemorrhage, sepsis, and ventilatory support were similar in both groups except for a higher rate of respiratory distress syndrome in those delivered after a TOL. Conclusion: The likelihood of VBAC success after TOL in preterm pregnancies is comparable to term gestations, with a lower risk of uterine rupture. Perinatal outcomes are similar with preterm TOL and RCD. TOL should be considered as an option for women undergoing preterm delivery with a history of prior cesarean delivery. [ABSTRACT FROM AUTHOR]

Background: 17-alpha Hydroxyprogesterone caproate for prevention of recurrent preterm birth is recommended for use in the United States.Objective: We sought to assess the clinical effectiveness of 17-alpha hydroxyprogesterone caproate to prevent recurrent preterm birth ≤35 weeks compared to similar births in our obstetric population prior to the implementation of 17-alpha hydroxyprogesterone caproate.Study Design: This was a prospective cohort study of 17-alpha hydroxyprogesterone caproate in our obstetric population. The primary outcome was the recurrence of birth ≤35 weeks for the entire study cohort compared to a historical referent rate of 16.8% of recurrent preterm birth in our population. There were 3 secondary outcomes. First, did 17-alpha hydroxyprogesterone caproate modify a woman's history of preterm birth when taking into account her prior number and sequence of preterm and term births? Second, was recurrence of preterm birth related to 17-alpha hydroxyprogesterone caproate plasma concentration? Third, was duration of pregnancy modified by 17-alpha hydroxyprogesterone caproate treatment compared to a prior preterm birth?Results: From January 2012 through March 2016, 430 consecutive women with prior births ≤35 weeks were treated with 17-alpha hydroxyprogesterone caproate. Nearly two thirds of the women (N = 267) began injections ≤18 weeks and 394 (92%) received a scheduled weekly injection within 10 days of reaching 35 weeks or delivery. The overall rate of recurrent preterm birth was 25% (N = 106) for the entire cohort compared to the 16.8% expected rate (P = 1.0). The 3 secondary outcomes were also negative. First, 17-alpha hydroxyprogesterone caproate did not significantly reduce the rates of recurrence regardless of prior preterm birth number or sequence. Second, plasma concentrations of 17-alpha hydroxyprogesterone caproate were not different (P = .17 at 24 weeks; P = .38 at 32 weeks) between women delivered ≤35 weeks and those delivered later in pregnancy. Third, the mean (±SD) interval in weeks of recurrent preterm birth before 17-alpha hydroxyprogesterone caproate use was 0.4 ± 5.3 weeks and the interval of recurrent preterm birth after 17-alpha hydroxyprogesterone caproate treatment was 0.1 ± 4.7 weeks (P = .63). A side effect of weekly 17-alpha hydroxyprogesterone caproate injections was an increase in gestational diabetes. Specifically, the rate of gestational diabetes was 13.4% in 17-alpha hydroxyprogesterone caproate-treated women compared to 8% in case-matched controls (P = .001).Conclusion: 17-alpha Hydroxyprogesterone caproate was ineffective for prevention of recurrent preterm birth and was associated with an increased rate of gestational diabetes. [ABSTRACT FROM AUTHOR]

The article comments on the increase in cesarean delivery that is coincidental with the rise in preterm births in the U.S. According to the author, increased cesarean delivery use has actually occurred in all gestational age groups, from less than 32 weeks to more than 42 weeks. The rate of preterm births at less than 37 completed weeks is associated with multiple births resulting from developed reproductive technologies.

Objective: Our purpose was to evaluate the placental pathology in women with preeclampsia occurring at varying gestational ages. Study Design: This was a secondary analysis of a prospective observational study of placentas from prespecified complicated pregnancies routinely submitted for standardized examination. For this study, a database of placental diagnoses from liveborn singleton gestations without major malformations was linked to a computerized obstetric database. The rates of standardized placental findings including vascular (atherosis, infarction) and nonvascular (hyperplasia) changes were evaluated according to gestational age at diagnosis of preeclampsia. Results: Between Jan. 1, 2001, and Sept. 30, 2007, a total of 7122 women with pregnancies complicated by preeclampsia were delivered at our hospital. Of these, 1210 (17%) had placental examinations. Within this cohort, 209, 355, and 646 women were diagnosed with preeclampsia at gestations of 240/67 to 336/7, 340/7 to 366/7, and 370/7 weeks or longer, respectively. Placental findings revealed hypoplasia was significantly associated with preeclampsia early in the third trimester, and histological evidence of placental vascular lesions was significantly increased at gestations of 240/67 to 336/7 weeks (53%) compared with 34% and 26% at 340/7 to 366/7 and 37 weeks or longer, respectively (P < .001). Conclusion: The placentas of women with preeclampsia onset before 34 weeks' gestation were significantly different from those with preeclampsia at term. The former group demonstrated placental findings predominantly consistent with insufficiency because of vascular abnormalities. Such differing placental findings support the hypothesis that preeclampsia is a different disease, depending on the gestational age at diagnosis. [Copyright &y& Elsevier]

Objective: To compare morbidity among small-for-gestational-age (SGA; birth weight less than the 10th percentile for gestational age), appropriate-for-gestational-age (AGA; birth weight 10th to 90th percentile; reference group), and large-for-gestational-age (LGA; birth weight greater than the 90th percentile) neonates in apparently uncomplicated pregnancies at term (37 weeks of gestation or greater).Methods: This secondary analysis, derived from an observational obstetric cohort of 115,502 deliveries, included women with apparently uncomplicated pregnancies of nonanomalous singletons who had confirmatory ultrasound dating no later than the second trimester and who delivered between 37 0/7 and 42 6/7 weeks of gestation. We used two different composite neonatal morbidity outcomes: hypoxic composite neonatal morbidity for SGA and traumatic composite neonatal morbidity for LGA neonates. Log Poisson relative risks (RRs) with 95% CIs adjusted for potential confounding factors (nulliparity, body mass index, insurance status, and neonatal sex) were calculated.Results: Among the 63,436 women who met our inclusion criteria, SGA occurred in 7.9% (n=4,983) and LGA in 8.3% (n=5,253). Hypoxic composite neonatal morbidity was significantly higher in SGA (1.1%) compared with AGA (0.7%; adjusted RR 1.44, 95% CI 1.07-1.93) but similar between LGA (0.6%) and AGA (adjusted RR 0.84, 95% CI 0.58-1.22). Traumatic composite neonatal morbidity was significantly higher in LGA (1.9%) than AGA (1.0%; adjusted RR 1.88, 95% CI 1.51-2.34) but similar in SGA (1.3%) compared with AGA (adjusted RR 1.28, 95% CI 0.98-1.67).Conclusion: Among women with uncomplicated pregnancies, hypoxic composite neonatal morbidity is more common with SGA neonates and traumatic-composite neonatal morbidity is more common with LGA neonates. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To generate birth weight curves based on the obstetric estimate of gestational age as specified in the revised 2003 U.S. birth certificate. METHODS: Using National Center for Health Statistics data from 2011, we constructed birth weight curves for neonates between 24 and 42 weeks of gestation. Curves were developed using the obstetric estimate of gesta-tional age that is included in the revised 2003 U.S. birth certificate, which, when available, incorporates ultra-sound dating information. Live-born singleton neonates between 500 and 6,000 g without malformations were included. These curves were compared with curves we generated using 1991 data on which the current national reference of Alexander and colleagues is based, a refer-ence that used only last menstrual period to establish gestational age. RESULTS: The 1991 curves were based on 3,684,778 U.S. live births and the 2011 on 3,252,011 births. Birth weight percentile values were greater from 28 to 36 weeks of gestation in the 1991 data set. That is, the birth weights for preterm neonates were overestimated when 1991 reference curves were used compared with the pro-posed 2011 reference. For example, in 1991, a birth weight of 2,000 g was at the 50th percentile between 31 and 32 weeks of gestation, whereas in 2011, a birth weight of 2,000 g now corresponds to the 50th percentile between 33 and 34 weeks of gestation. CONCLUSIONS: Our revised reference curve for the United States provides an updated national reference for birth weight. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study that examines the natural history of pregnancies in women with false preterm labor symptoms. The study shows that women who were sent home for false labor have a similar rate of birth before 34 weeks of gestation and do not have an increased risk for early preterm birth or neonatal mortality. It concludes that women with false preterm labor are at risk for late preterm birth.

The article estimates the relationship between the number of prior cesarean deliveries and pregnancy outcomes among women with placenta previa. Results reveal that multiple measures of maternal morbidity, such as coagulopathy, hysterectomy, and pulmonary edema, increased in frequency as the number of prior cesarean deliveries increased. Gestational age at delivery and negative perinatal outcome were not related to the number of prior cesarean deliveries.

OBJECTIVE: To estimate a normal reference range for thyroid-stimulating hormone (TSH) at each point in gestation in singleton and twin pregnancies. METHODS: All women enrolling for prenatal care from December 2000 through November 2001 underwent prospective TSH screening at their first visit. Separate homograms were constructed for singleton and twin pregnancies using regression analysis. Values were converted to multiples of the median (MOM) for singleton pregnancies at each week of gestation. RESULTS: Thyroid-stimulating hormone was evaluated in 13,599 singleton and 132 twin pregnancies. Thyroid-stimulating hormone decreased significantly during the first trimester, and the decrease was greater in twins (both P < .001). Had a nonpregnant reference (0.4-4.0 mU/L) been used rather than our nomogram, 28% of 342 singletons with TSH greater than 2 standard deviations above the mean would not have been identified. For singleton first-trimester pregnancies, the approximate upper limit of normal TSH was 4.0 MoM, and for twins, 3.5 MoM. Thereafter, the approximate upper limit was 2.5 MoM for singleton and twin pregnancies. CONCLUSION: If thyroid testing is performed during pregnancy, nomograms that adjust for fetal number and gestational age may greatly improve disease detection. Values expressed as multiples of the median may facilitate comparisons across different laboratories and populations. [ABSTRACT FROM AUTHOR]

Background: At any given gestational age, infants with low birth weight have relatively high morbidity and mortality. It is not known, however, whether there is a threshold weight below which morbidity and mortality are significantly greater, or whether that threshold varies with gestational age. Methods: We analyzed the neonatal outcomes of death, five-minute Apgar score, umbilical-artery blood pH, and morbidity due to prematurity for all singleton infants delivered at Parkland Hospital, Dallas, between January 1, 1988, and August 31, 1996. A distribution of birth weights according to week of gestation at birth was created. Infants in the 26th through 75th percentiles for weight served as the reference group. Data on preterm infants (those born at 24 to 36 weeks of gestation) were analyzed separately from data on infants delivered at term (37 or more weeks of gestation). Results: A total of 122,754 women and adolescents delivered singleton live infants without malformations between 24 and 43 weeks of gestation. Among the 12,317 preterm infants who were analyzed, there was no specific birth-weight percentile at which morbidity and mortality increased. Among 82,361 infants who were born at term and whose birth weights were at or below the 75th percentile, however, the rate of neonatal death increased from 0.03 percent in the reference group (26th through 75th percentile for weight) to 0.3 percent for those with birth weights at or below the 3rd percentile (P<0.001). The incidence of five-minute Apgar scores of 3 or less and umbilical-artery blood pH values of 7.0 or less was approximately doubled for infants at or below the 3rd birth-weight percentile (P=0.003 and P<0.001, respectively). The incidence of intubation at birth, seizures during the first day of life, and sepsis was also significantly increased among term infants with birth weights at or below the 3rd percentile. These differences persisted after adjustment for the mother's race and parity and the infant's sex. Conclusions: Mortality and morbidity are increased among infants born at term whose birth weights are at or below the 3rd percentile for their gestational age. (N Engl J Med 1999;340:1234-8.) [ABSTRACT FROM AUTHOR]