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The aim of this study was to evaluate the performance of multivariate models using Near infrared (NIR) spectra for predicting total extractives content of solid and powdered wood of planted and native species from tropical savanna. NIR spectra were recorded on the milled wood and radial surface of solid wood specimens of Cedrela sp., Jacaranda sp., Apuleia sp., Aspidosperma sp. and clones of Eucalyptus hybrids via an integrating sphere and fiber optics probe. NIR spectral signatures were evaluated by Principal Component Analysis (PCA) and then associated to the total extractive content quantified by extraction in toluene/ethanol (2:1) solutions, pure ethanol and hot water by Partial Least Squares (PLS) regressions. PCA revealed that NIR spectra measured in solid wood by integrating sphere gave a better discrimination of wood species. A global PLS model was developed based on NIR obtained by integrating sphere with satisfactory estimations both for solid wood (R²cv= 0.87, RMSECV= 1.08%) and wood powder (R²cv= 0.85, RMSECV= 1.19%). An independent test-set validation was performed with 25% of the samples and yielded R²p= 0.93 and RMSEP= 0.95% (for solid wood) and R²p= 0.87 and RMSEP= 1.40% (for wood powder). Both models can be applied for rapid screenings, though models developed from NIR spectra by integrating sphere on solid wood are considered more suitable for rapid predictions of extractive content in unknown wood specimens.

Determining the wood properties is fundamental because these properties are directly related to wood quality. The near-infrared (NIR) spectroscopy technique has been used to determine various properties of wood. However, even with promising results, NIR spectroscopy needs to be further investigated to evaluate the robustness of its estimates. The objective of this study was to develop regression models from NIR spectra to estimate the basic density and the extractive and lignin contents of wood as well as to verify their robustness through independent and cross-validation. NIR spectra were initially obtained through an integration sphere and optical fiber for the transverse and radial faces of solid wood and through an integration sphere for powdered wood. The wood basic density and the extractive and lignin contents were determined by conventional methods in 180 and 143 specimens, respectively. The samples were collected from Eucalyptus urophylla × Eucalyptus grandis clones aged 5 years. The basic density and extractive and lignin content values were correlated with the NIR spectra by a partial least squares regression. The best models for estimating the basic density of the wood were generated from the spectra obtained on the transverse surface, both with the integration sphere pathway and in the optical fiber pathway. For estimating the chemical properties of wood, the best models were developed from the powdered wood via the integration sphere for assessing the extractive content, Klason lignin, acid-soluble lignin content and total lignin. In all the models, the mathematical treatment of the data by the first derivative was essential for better fitting the models and reducing the error. We concluded that NIR spectroscopy was effective for the estimation of basic density and extractive and lignin contents of wood.

As a faster, reliable, and low cost technique, applicable to large samplings, near infrared (NIR) spectroscopy technology has been widely applied for high-throughput phenotyping in forest breeding programmes. The aim of this study was to develop multivariate models for estimating the chemical and physical properties of juvenile wood based on NIR signatures of milled wood. Moreover, two approaches, namely, external validation by clone and by age, were tested to validate the model for estimating extractive content. NIR spectra of wood specimens taken from three clones of Eucalyptus urophylla (one to six years old) grown in southern Brazil were used to calibrate and validate models for predicting the wood basic density, total extractives, ash content, holocellulose content, syringyl to guaiacyl ratio (S/G) and elementary components of the wood. PLS-R models were validated by an independent set of wood specimens and presented promising statistics for the estimating wood density (R2p = 0.768), extractives (R2p = 0.912), ash (R2p = 0.936) and carbon (R2p = 0.697) contents from NIR signatures measured in the milled wood of young trees. Furthermore, NIR models for estimating the extractive content of wood were validated using the clones or ages left out of the training sets. Most models presented satisfactory statistics (R2 > 90%) and could be applied to routine laboratory analyses or to select potential trees in Eucalyptus breeding programmes.

The influence of tree spacing on the wood/bark ratio is unknown in young fast-growing Eucalyptus trees. The objective of this study was to evaluate the effect of plant spacing on the wood and bark production along the Eucalyptus stem. Four genetic materials were planted in four spacings: 3×1 m, 3×2 m, 3×3 m and 3×4 m. Three 5-year-old trees from each clone and in each plant spacing were harvested. Cross-sectional discs (thickness: 30 mm) were cut from each tree along the stem (0%, 25%, 50%, 75% and 100% of the total tree height) and at 1.3 m above ground, totaling 288 disks (4 spacings × 4 clones × 3 replicates × 6 axial positions). The wood thickness was measured at six random and equidistant points around the perimeter using a gauge and means were calculated from each disc. Six cross diameters were measured for each debarked disc. After obtaining the averaged bark thickness and wood diameter, the bark content was calculated as the ratio between the surface area occupied by the bark and the total area of the stem in each level. In the narrowed plant spacing (3×1), the trees had a mean diameter of 7.4 cm, while at the spacing 3×4 the diameter of the trees was 91% higher (14.11 cm) at breast height. The increase in plant spacing from 3 to 12 m2 per tree resulted in an increase in bark thickness (56.7%) from 1.94 mm to 3.04 mm, but caused a reduction of bark content (16%) from 9.66% to 8.11%. Our findings show that trees grown under wider spacing tend to produce thicker bark. The bark thickness and the effect of plant spacing on the bark thickness decreased in the base-top direction. The correlation between bark thickness and wood diameter increases from 0.682 to 0.825 with the increase of spacing between trees. In contrast, the bark thickness to bark content correlation decrease from 0.735 to 0.15 with increased plant spacing. The stand density significantly affected the variation of the stem diameter, bark thickness and bark content of Eucalyptus plantations.

Background: The chemical compounds in coffee are important indicators of quality. Its composition varies according to several factors related to the planting and processing of coffee. Thus, this study proposed to use near-infrared spectroscopy (NIR) associated with partial least squares (PLS) regression to estimate quickly some chemical properties (moisture content, soluble solids, and total and reducing sugars) in intact green coffee samples. For this, 250 samples produced in Brazil were analyzed in the laboratory by the standard method and also had their spectra recorded., Results: The calibration models were developed using PLS regression with cross-validation and tested in a validation set. The models were elaborated using original spectra and preprocessed by five different mathematical methods. These models were compared in relation to the coefficient of determination, root mean square error of cross-validation (RMSECV), root mean square error of test set validation (RMSEP), and ratio of performance to deviation (RPD) and demonstrated different predictive capabilities for the chemical properties of coffee. The best model was obtained to predict grain moisture and the worst performance was observed for the soluble solids model. The highest determination coefficients obtained for the samples in the validation set were equal to 0.810, 0.516, 0.694 and 0.781 for moisture, soluble solids, total sugar, and reducing sugars, respectively., Conclusion: The statistics associated with these models indicate that NIR technology has the potential to be applied routinely to predict the chemical properties of green coffee, and in particular, for moisture analysis. However, the soluble solid and total sugar content did not show high correlations with the spectroscopic data and need to be improved. © 2020 Society of Chemical Industry., (© 2020 Society of Chemical Industry.)

Background: Most laboratory parameters change during pregnancy. A serial study of a large number of routine haematological and biochemical blood parameters and biochemical urine parameters was conducted in a group of 66 healthy nulliparous pregnant women, who had an uncomplicated pregnancy., Methods: Blood samples and 24-h urine samples were obtained at four weeks intervals during pregnancy and at 1 (1P) and 6 (6P) weeks after delivery., Results: During pregnancy, haemoglobin concentration, haematocrit and erythrocyte count were lower, mean cell volume was not different, and mean cell haemoglobin and mean cell haemoglobin concentration were enhanced. The platelet count during pregnancy was not different from the level at 6P but increased 60% at 1P. Serum ferritin decreased 50% whereas plasma fibrinogen increased 100%. Serum creatinine (-28%), uric acid (-35%) and urea (-40%) concentrations were reduced during pregnancy. The serum concentrations of sodium (-4 mmol/l) and potassium (-0.2 mmol/l) were lower, but serum chloride was unaltered. Serum protein and albumen concentrations declined by 7.8 and 9.4 g/l respectively. The serum concentrations of bilirubin, ALAT, ASAT and gamma-GT remained unaltered. Serum LDH was 30% above normal non-pregnant values at 1P. The heat-stable alkaline phosphatase level increased in the third trimester. Heat-stable and heat-labile fractions were both elevated at 1P. The serum osmolality was 9 mosmol/kg lower and urine volume was about 25% higher during pregnancy. The creatinine excretion was unaltered but creatinine clearance increased by 25%., Conclusions: The concentrations of most components change during pregnancy. The interpretation of results of laboratory tests in pregnant women should be made with caution.

Objective: To study the possible pathophysiological implications of long continued dietary sodium restriction in pregnancy., Design: Longitudinal prospective randomized study of the effects of a low sodium diet compared with unrestricted sodium intake in pregnancy., Setting: Academic Department of Obstetrics and Gynaecology at Sint Radboud Hospital, Nijmegen, The Netherlands., Subjects: 42 healthy nulliparous women., Intervention: A low sodium diet (20 mmol sodium daily) started in the 14th week of pregnancy and stopped after delivery., Main Outcome Measures: Maternal weight gain, food intake, blood pressure, cardiac output, systemic vascular resistance, haematocrit and birthweight., Results: Total maternal weight gain and dietary energy intake during pregnancy and weight at 1 and 6 weeks postpartum were significantly lower in the low sodium group. Blood pressure during pregnancy did not show major differences. Stroke volume and cardiac output during pregnancy were significantly lower in the low sodium group whereas systemic vascular resistance was significantly higher. Haematocrit values in the low sodium group tended to be lower during pregnancy, but were significantly lower at 1 and 6 weeks postpartum than in the unrestricted group. Placental and birthweights were not significantly different between the two groups., Conclusions: Chronic dietary sodium restriction during pregnancy is characterized by a diminished body fat accumulation and a reduction in circulating volume, due to a decrease in both plasma and red cell volume, in combination with a high systemic vascular resistance without major effects on blood pressure and birthweight.

This article reviews the major milestones in obstetric research in the past 90 years, which have lead to the wide-spread use of salt restriction during pregnancy. Possibly the most ardent advocate of the view that salt plays a crucial role in eclampsia was De Snoo (1877-1949), a Dutch obstetrician. However, despite many enthusiastic clinical reports, no convincing evidence has ever been produced that salt restriction helps in the prevention of hypertension during pregnancy.

The effect of chronic methadone treatment upon the serum levels of Estradiol (E2), Progesterone (P), Prolactin (Prl), monkey chorionic gonadotropin (mCG), dehydroepiandrosterone sulfate (DHEAS) and Cortisol (C) in pregnant Cynomolgus monkeys (Macaca fascicularis) is described in comparison with the hormone levels in a control group. Only DHEAS was significantly decreased in late pregnancy in the methadone group. From these data it can not be concluded that methadone treatment compromises (feto)placental function. The observed intra-uterine growth retardation in the methadone treated group might be a result of a direct influence of methadone upon growth.

The effects of dietary sodium restriction and posture on plasma concentrations of atrial natriuretic peptide (ANP), aldosterone and free aldosterone were investigated in ten women between weeks 29 and 33 of normal pregnancy. Hormone levels were studied during unrestricted sodium intake and on day 6 of a low sodium diet. On both occasions venous blood was obtained in the sitting as well as in the left lateral tilt position. Plasma concentrations of ANP during the unrestricted sodium intake were not raised compared with control values in healthy non-pregnant females. Recovery experiments showed no differences in the degradation of ANP in blood from pregnant and non-pregnant women. Plasma concentrations of ANP significantly decreased (by 32%) in response to the low sodium regime in both positions. Concentrations of aldosterone and free aldosterone (in women in the sitting position) increased twofold after sodium restriction. Mean values of ANP were higher in women in the left lateral tilt position that in those in the sitting position, but the difference was not significant. Concentrations of aldosterone and free aldosterone were significantly lower (by around 30%) in women in the left lateral tilt position compared with those in the sitting posture.

Synthesis and secretion of atrial natriuretic peptide (ANP) is not confined to the heart, but also present in other tissues. ANP is known to affect steroidogenesis in the ovary. To assess the possibilities that (a) the human ovary is a source of ANP secretion as well, and (b) ovarian ANP stimulates progesterone secretion, we investigated ANP as well as progesterone concentrations in preovulatory ovarian follicular fluid form women in an in vitro fertilization program. In all women detectable ANP immunoreactivity was found in ovarian follicular fluid (range 3.3-60.1 pg/ml). Follicular fluid concentrations were low in all but 1 women who demonstrated a higher ANP level in follicular fluid than in plasma. Follicular ANP and progesterone concentrations were not significantly correlated. These preliminary results suggest that the ovary could well be a site of ANP secretion. If and how ovarian ANP activity affects progesterone secretion remains as yet unknown.

A case of acardius acephalus in a Macaca fascicularis is reported. This congenital anomaly occurs only in multiple-birth gestations (most commonly monozygotic twins). Artery-to-artery and vein-to-vein anastomoses appear to be a constant feature. This condition is very rare in man and probably even more so in monkeys. Classification and theories on etiology are discussed.

Plasma concentrations of atrial natriuretic peptide (ANP) were determined ante- and post-partum in 7 healthy primiparous women. ANP was measured at weekly intervals from the 35th week of pregnancy onwards and throughout the puerperium up to the sixth week post-partum. In all seven patients the mean of the ANP values during the first four days post-partum was higher than in late pregnancy. The mean ANP level from the 6th day up to the 42nd day showed a marked decrease compared with the first four days after birth, which, however, did not differ significantly from the mean plasma concentration in late pregnancy. In conclusion, ANP is markedly elevated during the first few days post-partum compared with plasma levels in the normal late pregnancy and the subsequent puerperium.

A successful pregnancy is reported in a patient following renal transplantation and urinary diversion. The second half of pregnancy was complicated by hypertension, impaired renal function and obstruction of the ureter in the 35th wk. The latter complication required early termination of pregnancy by cesarean section. A healthy infant was delivered who survived without complications. Maternal renal function returned to pre-pregnancy levels following delivery.

In the 32nd wk, fenoterol was administered to a patient during her first pregnancy because of premature rupture of the membranes and uterine contractions after 2 wk of medication. At 8 microgram/min of fenoterol, total irregularity of the maternal pulse occurred. In the 35th wk, cesarean section had to be performed because of fetal asphyxia at 5 cm of cervical dilatation. Intensive care treatment of the mother was necessary during the postoperative phase. The diagnosis of pre-existing congestive cardiomyopathy was made. Non-invasive examination of the heart is advised before beta-adrenergic drugs are given.

The literature reporting Doppler ultrasound flow velocity waveform analysis of the umbilical artery and its applications for detecting intrauterine growth retardation (IUGR) is growing rapidly. Several indices originally introduced to evaluate different vascular beds in adults, are used to assess the vascular bed resistance downstream the umbilical artery (i.e. the placental bed). A higher resistance in this placental bed causes a decreased end-diastolic flow, which is described in combination with IUGR. The three most commonly used flow indices are: A/B ratio, Resistance Index (RI = (A-B)/A) and Pulsatility Index (PI = (A-B)/mean). In this study we evaluated which of these indices correlated best with IUGR. We calculated the three above mentioned indices from the same recordings of the blood flow (at a gestational age of 34 +/- 2 weeks) and correlated the results with the subsequent birthweight of the child. In the studied group (n = 48) 15 children were small for gestational age (SGA = less than P 10) and 33 children were appropriate for gestational age (AGA = greater than or equal to P 10). All three indices showed a significant difference in value between AGA and SGA children (see table III). The Spearman correlation-coefficients were calculated and were approximately one. So there was a high correlation between all three indices. This indicates that the different indices have the same relation to IUGR. Thus, no arguments were found to prefer one index above the other. In the second part of the study we investigated the validity of these indices to predict IUGR. The validity can be estimated from two components: the sensitivity and specificity. Both sensitivity and specificity are determined by the value of the index which discriminates between AGA and SGA. Changes in this discriminating value (the so-called cut-off point) will change both sensitivity and specificity. This last effect can be visualized in the Receiver-Operating-Characteristic (ROC) curve, which plots sensitivity against specificity for different cut-off points (see figures 4 and 5). Arbitrarily sensitivity and specificity were calculated for the cut-off points PI = 1.1 and A/B ratio = 3.0. Choosing these cut-off points, the same specificity of 87.9% with a sensitivity of 53.3% were found (table IV). It is concluded, that the sensitivity of the PI of the umbilical artery in predicting growth retardation with acceptable specificity is rather disappointing. A possible reason for this is discussed.(ABSTRACT TRUNCATED AT 400 WORDS)

Serum levels of estradiol (E2), progesterone (P), prolactin (Prl), monkey chorionic gonadotropin (mCG), dehydroepiandrosterone sulfate (DHEAS), and cortisol (C) in pregnant cynomolgus monkeys are described. mCG, E2, and Prl patterns resembled those of pregnant rhesus monkeys. P patterns differed from data from the literature. DHEAS patterns did not follow E2 patterns. C levels did not change during pregnancy.

In 19 normal pregnancies between 37 and 39 weeks of gestation, the blood flow velocity waveform (FVW) of the umbilical artery was studied in relation to fetal breathing movements, fetal heart rate (FHR) and the fetal heart rate patterns (FHRPs) A and B. FHRP A is stable, with a narrow oscillation bandwidth, FHRP B shows a wider oscillation bandwidth. Although for state-assessment it is necessary to record three variables simultaneously, the linkage of these variables in the near-term healthy fetus is such, that FHRP A and B may be used for the assignment of behavioural states 1F and 2F. The FVW was characterized by the Pulsatility-Index (PI). Presence of fetal breathing movements strongly disturbed the regularity of the FVW. A significant inverse relationship between FHR and PI was established. A weighted regression coefficient was calculated: PI decreases 0.0075 with an increase of FHR of 1 beat per minute (PI140 = PI / 0.0075(FHR - 140]. The PI was higher during periods of FHRP A as compared to FHRP B. However, this difference disappeared, when the influence of FHR was taken into account by normalising all PIs to a standard heart rate level of 140 bpm. One should perform the umbilical artery blood flow measurements in absence of fetal breathing--(causing irregularity of the FVW) and body movements (because of accompanying FHR accelerations) and FHR should be taken into account when evaluating the FVWs.

The effects of maternal exercise were studied in 20 healthy women with uncomplicated pregnancies. A continuous-wave Doppler ultrasound system was used to record arterial flow velocity waveforms from the ascending vasculature downstream from the uterine artery. The fetal heart rate was monitored with a Doppler ultrasound cardiotocograph. No significant change was found in the uterine blood flow velocity waveform post-exercise, as expressed by the pulsatility index, suggesting absence of change in the uterine vascular bed resistance. The fetal heart rate significantly increased after exercise.

A retrospective study to detect the frequency of lethal lung hypoplasia in 48 cases with prolonged rupture of membranes (greater than 7 days) before 34 weeks' gestation was made. Fourteen infants died (29%), but only four deaths (8.3%) were due to lung hypoplasia. Three infants with lung hypoplasia had their membranes ruptured before 20 weeks' gestation and showed echoscopically a persistent oligohydramnios, as did the one with rupture at 26 weeks. Neither the duration of rupture of membranes nor the gestational age at the time of rupture showed any influence on the occurrence of lung hypoplasia. The rupture of membranes before 20 weeks' gestational age with resulting persistent oligohydramnios will certainly lead to lung hypoplasia.

The dose-dependent effects of progesterone (P) on estradiol (E2)-induced gonadotropin release were investigated in the early follicular phase of female rhesus monkeys by sc implanting Silastic capsules containing either crystalline E2 or P. In group 1, E2 alone (250 pg/ml) and E2 in combination with P (1.5, 3, and 5 ng/ml) were administered in four consecutive experiments. The lowest P dosage (1.5 ng/ml) advanced the time of the maximal gonadotropin release, but the magnitude seemed to be decreased compared to that in the experiment with E2 alone. The higher P dosages (3 and 5 ng/ml) blocked the previously observed E2-induced gonadotropin surges. In group 2, E2 alone (250 pg/ml) and E2 in combination with P (1.5, 5, and 20 ng/ml), added 46 h after E2, were administered in four consecutive experiments. In all experiments, P advanced and increased the gonadotropin peaks. The FSH surges could be increased even further in the experiments with the two highest P dosages (5 and 20 ng/ml). After this period of facilitated gonadotropin secretion, we observed lower gonadotropin levels than those in the control experiment with E2 alone. This effect became more apparent by increasing by P dosage. These results point to a biphasic effect of P across time and dosage on the release of gonadotropins.

To the best of our knowledge no recent literature on pregnancy in patients with primary pulmonary hypertension is available. In this case report a patient is presented who possibly suffered from primary pulmonary hypertension. The clinical course is described and some data from the literature are presented. The patient died post partum probably due to this disease; however, the postmortem examination, which undoubtedly could have proven this, was refused.

A generally accepted management of heroin addiction during pregnancy is treatment with methadone, which reduces the complications of heroin addiction considerably. Reports in the literature are still contradictory, however, about the influence of methadone upon birthweight. In pregnant Cynomolgus monkeys (Macaca fascicularis) the effect of chronic treatment with rather high dosages of methadone upon birthweight was studied under standardized conditions. Birthweights were significantly lower in the methadone-treated animals.

In 10 patients with severe hypertension during pregnancy (6 patients with preexisting hypertension and 4 with severe preeclampsia) Swan-Ganz measurements were done in order to detect and correct a reduced circulating volume and lower the blood pressure. It appeared that 6 patients had a reduced circulating volume (group I) and 4 patients a normal circulating volume (group II). In both groups there were 2 patients with severe preeclampsia; most patients were referred and had antihypertensive medication before and most infants had a birthweight less than the 10th centile. A difference was found in prolongation of pregnancy if counted from the first hemodynamic measurement (and start of therapy): on average 25 days in group I (despite careful volume correction and vasodilatation) versus on average 25 days in group II (vasodilatation only). Moreover, all infants but one were delivered by cesarean section, but fetal distress as indication for delivery was only noted in group I. Although Swan-Ganz measurements are very useful to determine filling state and effect of therapy it is concluded that once a reduced circulating volume is present one is too late to be able to prolong pregnancy considerably despite proper therapy of volume correction and vasodilatation. This makes Swan-Ganz measurements on "fetal indication" questionable.

Uterine artery blood flow velocity waveforms (FVW) were recorded longitudinally in normal pregnancies (n = 41) at 4-week intervals from a gestational age of 18 weeks onwards. Furthermore, reproducibility of the uterine artery FVWs and the relation with maternal heart rate (MHR) was studied. The uterine artery FVW showed a low resistance flow pattern already from 18 weeks onwards, with high diastolic flow velocity relative to systolic flow velocity. Mean values (+/- S.D.) for the Pulsatility-Index (PI) before and after 32 weeks of normal pregnancy were 0.73 (+/- 0.17) and 0.67 (+/- 0.15) respectively; for the A/B ratio these values were 1.98 (+/- 0.30) and 1.85 (+/- 0.25) respectively. Intra- and interobserver reproducibility could be established for uterine artery FVW analysis. A varying time-period between the FVWs (0-4 min), repositioning of the flow probe and different observers did not cause any systematic effect on the PI, although variation increased in case of a longer time-period between the FVWs. Overall variation of the PI in the reproducibility experiments appeared to be caused more by inter- than intrapatient variance. Inter- and intrapatient variance were in the same range for the results of the longitudinal study. A statistically significant, inverse relationship between uterine artery PI and MHR could be established in a majority of cases. The mean regression coefficient for all patients of the reproducibility study was -0.0061; PI decreases with 0.0061 when maternal heart rate increases 1 beats/min.

The maternal and fetal placental circulation was studied by recording of the blood flow velocity waveforms (FVW) of the uterine and umbilical artery (UFVW and UmbFVW) in 99 pregnant women. The FVW was quantitated by the Pulsatility-Index (PI). By analysing the UFVWs as well as the UmbFVWs, it was possible to define four groups of patients, based on normal versus abnormal PI on either side of the placenta. The group with abnormal FVWs on both sides of the placental bed showed the highest percentage of pathological phenomena. Uterine and/or umbilical artery FVW analysis was not sensitive in the prediction of small for gestational age (SGA), whereas it was a sensitive method for the prediction of fetal distress (FD) during pregnancy. For the latter, our data suggested that at a chosen specificity of 95%%. FVW analysis on both sides of the placental bed was more sensitive than separate UFVW or UmbFVW analysis.

Severe maternal complications during beta-mimetic therapy have been reported. In a study of maternal complications related to intravenous tocolysis, which covering a period of 2 years, we paid special attention to the maternal ECG before and during treatment. There was a high prevalence of pretreatment ECG changes: tachycardia (23.6%), disorders of impulse conduction (43.6%), ST-depression (14.5%) and disorders of repolarization (43.6%). During intravenous beta-mimetic therapy there was an increase in the prevalence of tachycardia, prolonged QT-time and disorders of repolarization. We also studied the course in time of the different ECG characteristics during treatment. With regard to the ST-depression, a possible physiological adaptation to the beta-mimetic drug is described. We could not find this possible adaptation with regard to the other ECG characteristics. None of the women in the studied group showed clinical signs of myocardial ischemia, notwithstanding the high prevalence of ECG changes. We conclude that the ECG criteria for discontinuation of tocolytic therapy need re-evaluation.

Survival of 188 infants born alive before the 34th wk of pregnancy is assessed in relation both to birthweight and duration of pregnancy. A logistic model is used which describes, based on these parameters, probabilities of 1-yr survival of relatively small populations in a continuous way. Although there may be differences between measured and estimated birthweight, this method might enable the perinatologist to estimate before birth the survival probabilities if he knows the duration of pregnancy and estimated birthweight.

Morbidity in the first year of life of 120 infants, born before the 34th wk of pregnancy, was studied in relationship to both duration of pregnancy and birthweight. Moreover, the interrelationships of morbidity in three time-periods (first-hour, first 28 days and first year after delivery) were studied. The major handicap rate at one year was 5%, without major handicaps in infants born before 29 wk or weighing less than 1250 g. This finding seems to justify intensive treatment of even the youngest and smallest infants. Significantly more morbidity in the first 28 days of life was found when intervention within the first hour after delivery was necessary, indicating that morbidity in the first hour after delivery may be a prognostic bad sign for morbidity in the first 28 days of life. However, no significant differences in handicap rates at one year of age were found in infants with and without morbidity in the first hour or in the first 28 days. This indicates that early morbidity will not necessarily be followed by morbidity in later life, but, on the other hand, absence of early morbidity does not preclude handicaps later on.

Uterine artery blood flow velocity waveforms (FVW) were recorded longitudinally in 41 women with undisturbed pregnancy as well as in 32 women with complicated pregnancy at 4-week intervals from a gestational age of 18 weeks onwards. Of these women, four did not complete the study. In a second group of 76 patients at least one FVW was recorded after admission to the obstetrical department because of complicated pregnancy. The Pulsatility-Index (PI) for normal pregnancy was based on the results of the 41 women with undisturbed pregnancy (Mulders et al. (1988) Early Hum. Dev., 17, 55-70). The complete study group (n = 145) was divided in two groups, based on the value of the last measured uterine artery PI before delivery in the abnormal PI group (PI greater than or equal to 1.02 before 32 weeks or PI greater than or equal to 0.91 after 32 weeks, n = 38) hypertension, fetal distress during pregnancy, premature delivery, small for gestational age babies (SGA) and lower placental weight were all significantly increased. In each of the groups of patients with either SGA, fetal distress during pregnancy, pre-existing hypertension with proteinuria and pregnancy-induced hypertension with or without proteinuria the mean PI was significantly increased as compared to the results in normal pregnancy. Sensitivity and specificity of the last uterine artery PI for the detection of SGA and/or fetal distress during pregnancy were 48.8% and 82.7%, respectively. The longitudinally studied women (n = 73) were divided in two groups, based on uterine artery PI before 32 weeks of gestation; in the abnormal PI group (PI greater than or equal to 1.02, n = 12) pregnancy was more complicated by premature delivery and low birth weight. Sensitivity for the early prediction of pathological pregnancies (at least one pathological phenomenon as mentioned above) was 30.4%, whereas specificity was 90.0%.