Maternal placental growth factor and soluble fms-like tyrosine kinase-1 reference ranges in post-term pregnancies: A prospective observational study.

BACKGROUND: Post-term pregnancies have increased risks for adverse fetal and maternal outcomes. Maternal concentrations of the placenta-associated proteins placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) have been identified as predictors for preeclampsia and fetal growth restriction, both syndromes of placental dysfunction. We have proposed that low maternal circulating PlGF and increased sFlt-1 are general markers for syncytiotrophoblast stress, which increases at and beyond term, even in apparently uncomplicated pregnancies. Our aim was to establish circulating PlGF, sFlt-1, and sFlt-1/PlGF reference ranges in healthy post-term pregnancies (gestational week ≥40+2), comparing with healthy term pregnancies and evaluating associations between time to delivery and biomarker percentiles. METHODS: Of 501 healthy, singleton post-term pregnancies prospectively recruited between September 2016 and December 2017 at our tertiary obstetric department, 426 with an uncomplicated delivery outcome contributed PlGF and sFlt-1 serum concentrations for reference range construction. A retrospective, cross-sectional, term group with an uncomplicated delivery outcome (n = 146) served as comparison. Differences in percentile values between groups and confidence intervals were calculated by quantile regression. RESULTS: In post-term pregnancies the 5th, 50th, and 95th percentiles for PlGF were: 70, 172, and 496 pg/mL; for sFlt-1: 2074, 4268, and 9141 pg/mL; and for sFlt-1/PlGF 5.3, 25.5, and 85.2. Quantile regression analyses comparing the post-term to the term group showed for PlGF a trend towards higher 10th through 30th percentiles, for sFlt-1 significantly higher 10th through 80th percentiles, and for sFlt-1/PlGF ratio significantly higher 30th percentile and significantly lower 95th percentile. PlGF below the 5th percentile and sFlt-1/PlGF ratio above the 95th percentile was associated with shorter time to delivery (p = 0.031 and p = 0.025, respectively). CONCLUSIONS: Our findings support the concept of increasing syncytiotrophoblast stress post-term in clinically healthy pregnancies. Whether post-term dysregulated angiogenic markers reflect a biological placental clock merits further investigation.

Polymorphism of the Oxytocin Receptor (OXTR) Gene Affects the Circulating Oxytocin Receptor Levels in Late-Term Pregnancy in a Turkish Population.

INTRODUCTION: Postterm and late-term pregnancies still remain a serious health problem, and underlying exact mechanisms are not fully elucidated. These mechanisms are influenced by many factors. OBJECTIVE: The aim of this study was to investigate the relationship between plasma oxytocin and oxytocin receptor levels and oxytocin receptor polymorphisms in term and late-term pregnant women. METHODS: Sixty-eight singleton pregnant women with late-term pregnancy and 83 singleton pregnant women with term parturition were included in this study. A comparison was performed between pregnancies and neonates born at term (37 0/7 and 41 6/7 weeks' gestation). Plasma oxytocin, oxytocin receptor, estradiol, and progesterone levels were measured by using enzyme-linked immunosorbent assay kits. TaqMan® SNP Genotyping Assays and qPCR ProbesMaster were used to investigate the polymorphisms of rs237911, rs2228485, rs53576, and rs2254298. RESULTS: There was not any difference in gene distributions of 4 common single-nucleotide polymorphisms of oxytocin receptor of rs237911, rs2228485, rs53576, and rs2254298 between subjects in late-term and term pregnancy groups. With rs53576 of the GG genotype, serum oxytocin levels were 21.50 ± 10.69 (ng/L) in the late-term group and 62.71 ± 18.01 (ng/L) in the term group (p = 0.049). Oxytocin receptor levels in the late-term and term pregnancy groups of the GG genotype were 17.92 ± 8.15 (pg/mL) and 45.77 ± 11.66 (pg/mL), respectively (p = 0.046). CONCLUSION: Our findings suggest that the rs53576 oxytocin receptor single-nucleotide polymorphism is associated with late-term pregnancy through acting by direct modulation of oxytocin and oxytocin receptor levels.

Amniotic fluid and umbilical cord serum erythropoietin in term and prolonged pregnancies.

OBJECTIVE: Erythropoietin - a hormone regulating erythropoiesis - is a biomarker of chronic fetal hypoxia. High erythropoietin levels in fetal plasma and amniotic fluid are associated with increased risk of adverse neonatal outcome. Since the risk of perinatal morbidity and mortality is increased in pregnancies beyond 41 gestational weeks, we evaluated erythropoietin levels in amniotic fluid and umbilical cord serum in apparently low-risk term (≥ 37 gestational weeks) and prolonged pregnancies (≥ 41 gestational weeks) with labor induction. STUDY DESIGN: This prospective cohort study comprised 93 singleton pregnancies at 37+0-42+1 gestational weeks, of which prolonged pregnancies numbered 63 (67.7%). Amniotic fluid samples were collected at time of labor induction by amniotomy. Umbilical cord blood samples for evaluation of pH, base excess, and umbilical cord serum erythropoietin were collected at birth. Erythropoietin levels were measured by immunochemiluminometric assay. Normal value of amniotic fluid erythropoietin level was defined as ≤ 3 IU/L, and abnormal value as ≥ 27 IU/L. Normal umbilical cord serum erythropoietin was defined as < 40 IU/L. Data on maternal pregnancy and delivery characteristics and short-term neonatal outcomes such as Apgar score were obtained from the hospital charts. Associations were calculated using Spearman's rank correlation coefficient. The Chi-square test, Fisher's exact test and the Mann-Whitney U test were utilized to determine differences in the study groups. RESULTS: Amniotic fluid erythropoietin levels correlated with gestational age (r = 0.261, p = 0.012) and were higher among prolonged pregnancies as compared to term pregnancies (p = 0.005). There were 78 (83.9%) vaginal deliveries, and among these erythropoietin levels in amniotic fluid correlated with the levels in umbilical cord serum (r = 0.513, p < 0.000). Umbilical cord serum erythropoietin levels correlated with gestational age among vaginal deliveries (r = 0.250, p = 0.027). Erythropoietin levels in amniotic fluid and umbilical cord serum did not correlate with umbilical artery pH or base excess, or other adverse pregnancy outcome. CONCLUSIONS: In vaginal deliveries erythropoietin levels in amniotic fluid correlated with the levels in umbilical cord serum. Erythropoietin levels correlated with gestational age, probably due to weakening placental function and relative hypoxemia occurring in advanced gestation. However, in this relatively low-risk study population erythropoietin was not related to adverse delivery outcome.

Physical fitness, serum relaxin and duration of gestation.

BACKGROUND: Women are recommended to perform regular exercise during pregnancy but the impact of physical fitness on duration of gestation and miscarriage is inconsistent. In addition, a dose-response relation between the amount of weekly exercise and increased risk of miscarriage in early pregnancy has been observed. Previous studies have mostly used an epidemiologic method. Larger studies using careful measurement of physical fitness are needed. Besides physical fitness, maternal circulating concentrations of the hormone relaxin have been associated with decreased duration of gestation. METHODS: A prospective cohort including 20 women with miscarriage and 460 women with spontaneous onset of labour, recruited from maternal health care centres in central Sweden, were examined in early pregnancy regarding estimated absolute peak oxygen uptake (VO2 peak, est.) by cycle ergometer test, and maternal circulating serum relaxin concentrations. RESULTS: Women with miscarriage displayed the highest level of absolute VO2 peak, est. (2.61 l/min) and the lowest serum relaxin concentrations (640 ng/l). Among women with spontaneous onset of labour, the mean absolute VO2 peak, est. increased successively from the lowest estimated oxygen uptake of 2.31 l/min among those with preterm birth (n = 28), to an oxygen uptake of 2.49 l/min among women with postterm birth (n = 31). An opposite trend was shown regarding serum relaxin concentrations from women with miscarriage to those with postterm birth. Serum relaxin concentrations, but not absolute VO2 peak, est. was significantly and independently associated with duration of gestation in women with miscarriages, and absolute VO2 peak, est., age and multiple pregnancy were independently associated with duration of gestation in women with spontaneous onset of labour. CONCLUSIONS: Physical fitness appears to be a protective factor of established pregnancies and not significantly involved in the risk of early miscarriage. Additional studies are needed to more clearly define the role of relaxin in miscarriage.

Pregnancy-associated plasma protein A levels and neonatal complications in post-date pregnancies.

OBJECTIVES: To assess the association between serum pregnancy-associated plasma protein A (PAPP-A) and free ß-human chorionic gonadotropin (free ß-hCG) in the first trimester and perinatal complications in post-date pregnancies. METHODS: A total of 4948 women, who delivered after 40 gestational weeks, were included. Labour was not induced routinely until 42 weeks. Serum levels of PAPP-A and free ß-hCG were determined at the first-trimester screening for Down syndrome. Neonatal complications were obtained from specific registration forms filled out by senior neonatologists. RESULTS: In post-date pregnancies, PAPP-A < 0.4 multiples of the median was associated with Apgar score of less than 7 at 5 min (ORadj 5.4, 95% CI 2.0-14.3), admission to the neonatal intensive care unit (ORadj 1.5, 95% CI 1.0-2.3) and newborn hypoglycaemia (ORadj 3.4, 95% CI 1.8-6.4). In small for gestation (SGA) neonates, the risk of hypoglycaemia was further increased (OR 14.6, 95% CI 3.4-58.0). Similar analyses were made with free ß-hCG, but no statistically significant associations were found. CONCLUSIONS: Low first-trimester serum PAPP-A was associated with increased neonatal morbidity in post-date pregnancies, particularly in newborns with SGA. Thus, PAPP-A may qualify the timing of induction of labour in these pregnancies.

Low 3rd trimester haemoglobin level and the risk of post-term pregnancy.

The aim of this study was to examine the association between haemoglobin (Hb) concentration during pregnancy and the risk of post-term pregnancy (PTP). Based on data from a population-based prenatal care programme in South China, a total of 102,484 women who delivered during 1995-2000 were identified. Haemoglobin concentration was determined by using standard methods. Risk of PTP was analysed according to severity of anaemia and multiple Hb categories. Multivariable logistic regression models were used to control potential confounding factors. Results showed that the overall prevalence rate of PTP in the population was 4.8% (4,947/102,484). The rate was 5.0%, 4.7% and 4.8% for women who were anaemic, while it was 4.5%, 4.4% and 4.2% for women who were non-anaemic in the 1st, 2nd and 3rd trimester, respectively. Although anaemia in either of the trimesters was not significantly associated with an increased risk of PTP, the risk was two-fold higher (odds ratio, 2.06; 95% CI, 1.18-3.59) for women whose last trimester haemoglobin concentration was lower than 80 g/l, when compared with women whose last trimester haemoglobin concentration was 140 g/l or higher. Our findings suggest that a very low 3rd trimester haemoglobin level is associated with an increased risk of PTP.

Associations of prenatal metabolic abnormalities with insulin and adiponectin concentrations in human milk.

BACKGROUND: Emerging evidence indicates that metabolic hormones are present in human milk, but, to our knowledge, no studies have investigated the impact of maternal metabolic status assessed during pregnancy on insulin and adiponectin concentrations in milk. OBJECTIVES: We aimed to investigate the associations of prenatal metabolic abnormalities with insulin and adiponectin in human milk and to compare the concentrations of these hormones in early and mature milk. DESIGN: Pregnant women aged ≥20 y with intention to breastfeed and without preexisting type 1 or 2 diabetes were recruited. Participants (n = 170) underwent a 3-h oral-glucose-tolerance test at 30 wk (95% CI: 25, 33 wk) gestation and donated early (the first week postpartum) and mature (3 mo postpartum) milk. RESULTS: Adiponectin and insulin concentrations in early milk were higher than those in mature milk (both P < 0.0001). Prenatal metabolic abnormalities, including higher pregravid BMI (ß ± SEE: 0.053 ± 0.014; P = 0.0003) and gravid hyperglycemia (0.218 ± 0.087; P = 0.01), insulin resistance (0.255 ± 0.047; P < 0.0001), lower insulin sensitivity (-0.521 ± 0.108; P < 0.0001), and higher serum adiponectin (0.116 ± 0.029; P < 0.0001), were associated with higher insulin in mature milk after covariate adjustment. Prenatal metabolic measures were not associated with milk adiponectin, but obstetrical measures that included nulliparity (0.171 ± 0.058; P = 0.004), longer duration of gestation (0.546 ± 0.146; P = 0.0002), and unscheduled cesarean delivery (0.387 ± 0.162; P = 0.02) were associated with higher adiponectin in early milk after covariate adjustment, including the time elapsed from delivery to milk collection. CONCLUSION: Maternal prenatal metabolic abnormalities are associated with high insulin concentrations in mature milk, whereas only obstetrical variables are associated with adiponectin concentrations in early milk.

Androgen levels are associated with blood pressure in pregnant women after term.

OBJECTIVE: To assess possible associations between androgen, estrogen and insulin levels and blood pressure in pregnant women after term, compared with the effect of other well-known factors. DESIGN: Cross-sectional retrospective study. SETTING: University Hospital, Trondheim region. POPULATION: Four hundred and eighty-nine post-term women with uncomplicated pregnancies. METHODS: Blood pressure measurements and fasting serum samples drawn one week beyond the estimated day of delivery (defined as 41(+2) weeks). MAIN OUTCOME MEASURES: Blood pressure, maternal age, body mass index, parity, smoking habits and serum levels of dehydroepiandrosterone sulfate, androstendione, free testosterone index, estradiol, estriol, progesterone, 17-hydroxy-progesterone and insulin. RESULTS: In univariate linear regression analyses, body mass index, androstendione, free testosterone index and insulin were positively associated and parity was negatively associated with both systolic and diastolic blood pressure. In multivariate linear regression analyses, systolic blood pressure was positively associated with body mass index and free testosterone index, but negatively associated with parity and 17-hydroxy-progesterone levels, while diastolic blood pressure was positively associated with age and free testosterone index, but negatively associated with parity and 17-hydroxy-progesterone levels. CONCLUSION: Testosterone may increase blood pressure in pregnant women, while 17-hydroxy-progesterone may have the opposite effect.

[Foetal scalp blood sampling: impact on the incidence of Caesarean section and assisted vaginal deliveries for non-reassuring foetal heart rate and its use according to gestational age]. / Reduktion der operativen Entbindungsrate durch den Einsatz von Mikroblutuntersuchungen bei auffälligem CTG unter Berücksichtigung des Gestationsalters.

BACKGROUND: Interpretation of a suspicious, non-reassuring or pathological foetal heart rate tracing does not provide any direct information about foetal oxygen saturation, blood gas status or the extent of changes in pH. Without foetal scalp blood sampling, such tracings often necessitate rapid intervention to deliver the baby by Caesarean section or assisted vaginal delivery. The aim of this study was to show the impact of foetal blood sampling on reducing the number of Caesarean sections and assisted vaginal deliveries in a clinical setting in such cases. MATERIALS AND METHODS: A retrospective study of the mode of delivery in 669 women where foetal scalp blood sampling had been performed for suspicious or pathological foetal heart rate monitoring, in the period 2008-2009 was undertaken. The gestational age of the foetus was also investigated. RESULTS: Because one or more results of foetal scalp pH were within the normal range an operative delivery could be avoided in 6.4% of the study population, in spite of the non-reassuring foetal heart rate monitoring. Foetal blood sampling was performed more frequently in post-term pregnancies. CONCLUSIONS: Foetal blood analysis still is an effective tool to reduce unnecessary operative deliveries and should be regularly included in intrapartum monitoring. The risk of foetal complications is low compared with the reduction in the rate of Caesarean sections and assisted vaginal deliveries. Obstetricians are evidently becoming more willing to carry out foetal scalp blood sampling with rising gestational age.

Biochemical and biophysical predictors of the response to the induction of labor in nulliparous postterm pregnancy.

OBJECTIVE: The objective of the study was to evaluate the clinical, sonographic, and hormonal variables that influence the success of labor induction in nulliparous postterm pregnancies. STUDY DESIGN: Fifty nulliparous women with a single postterm pregnancy receiving a slow-release prostaglandin estradiol pessary were prospectively enrolled, and clinical characteristics were analyzed in relation to success of induction of labor. Clinical, sonographic, and hormonal variables were analyzed by univariate statistical analysis and multivariate logistic regression for the prediction of successful induction. RESULTS: The group of patients delivering within 24 hours differed significantly from the remaining patients by higher Bishop scores, body mass indices, estradiol serum concentrations, estriol to estradiol ratios, and shorter cervices. The combination of cervical length and estriol to estradiol ratio achieved a sensitivity of 100% (95% confidence interval, 71.3-100%) and a specificity of 94.1% (95% confidence interval, 80.3-99.1%). CONCLUSION: Cervical length and the estriol to estradiol ratio represent good predictive indicators of the response to the induction of labor in postterm pregnancies.

Estrone sulfate and progesterone profiles during late gestation in recipient cows transferred embryos produced by nuclear transfer and in vitro fertilization.

The aim of present experiment was to evaluate the plasma concentrations of estrone sulfate (E(1)S) and progesterone (P(4)) during late gestation in recipient cows transferred embryos produced by nuclear transfer (NT) and in vitro fertilization (IVF). Blood samples were collected from recipients transferred embryos produced by NT (n=9) and IVF (n=13) at 160, 220, 240, 260 and 270 d of gestation and then at 5 d intervals until parturition. Plasma samples were analyzed for E(1)S and P(4) by ELISA. One NT and three IVF cows aborted between days 220 and 260 of gestation. Two NT and one IVF cow had prolonged gestation (over 290 d). One IVF cow had an overweight fetus (50 kg) after abortion (257 d). The patterns of changes in the concentrations of E(1)S during late gestation in the NT and IVF cows were almost identical. The NT and IVF cows that aborted had prolonged gestation and much higher E(1)S concentrations than the average. One NT cow aborted after 220 d of gestation and had a sudden high increase in its E(1)S concentration from 160 d to 220 d of gestation. The NT and IVF cows that had prolonged gestation also had significantly higher (P<0.05) P(4) concentrations than the average. These results raise the possibility that the E(1)S and P(4) profiles can be used to monitor some late gestational problems, such as higher birth weight, abortion and prolonged gestation.

Maternal plasma corticotropin-releasing factor (CRF) and CRF-binding protein (CRF-BP) levels in post-term pregnancy: effect of prostaglandin administration.

OBJECTIVE: Placental corticotropin-releasing factor (CRF) affects myometrial contractility and the secretion of several uterotonins such as prostaglandins (PGs); however, the activity of CRF is counteracted by CRF-binding protein (CRF-BP). At term and pre-term labor, CRF levels in maternal plasma are highest whereas those of CRF-BP are falling, and the cause of this fall is unknown. Thus, in this study, we investigated the effect of PG administration for labor induction on maternal plasma CRF and CRF-BP concentrations. DESIGN: Maternal plasma CRF and CRF-BP levels were assayed before and after (2 h later) induction of labor by intracervical administration of prostaglandin E(2) (PGE(2)), and at delivery in a group of healthy post-term pregnancies (n=18). Controls were women at term out of labor (n=22), who subsequently progressed to deliver a healthy singleton baby. METHODS: CRF was measured by two-site immunoradiometric assay, and CRF-BP was assayed by radioimmunoassay. RESULTS: Maternal plasma CRF levels were significantly (P<0.0001) lower and CRF-BP significantly (P<0.0005) higher in post-term than in term pregnancies. With respect to induction of labor, 2 mg PGE(2) were sufficient to increase maternal plasma CRF levels at delivery (P<0.005). While 0.5 mg PGE(2) significantly decreased maternal plasma CRF-BP levels at delivery (P<0.001), 2.0 mg PGE(2) significantly reduced CRF-BP concentrations both after 2 h (P<0.05) and at delivery (P<0.0001). CONCLUSIONS: In the light of the well-known stimulation of prostaglandin release by CRF, these data suggest a positive feedback effect of PGE(2) on maternal CRF release during induced labor.

Maternal plasma corticotrophin-releasing factor and urocortin levels in post-term pregnancies.

OBJECTIVE: Corticotrophin-releasing factor (CRF) and urocortin are two placental neuropeptides that are involved in the mechanisms of labour by modulating myometrial activity. Maternal plasma levels of both CRF and urocortin are increased at term and preterm labour, whilst those of CRF are reduced in women who are destined to experience post-term delivery. The present study evaluated maternal plasma levels in term and post-term pregnancies out of labour. DESIGN: A group of healthy pregnant women was enrolled and subdivided as follows: (i) at term out of labour (n = 19; 276 +/- 0.7 days of gestation; samples collected at the time of elective caesarean section due to previous uterine surgery); (ii) post-term (n = 19; 291 +/- 1.4 days of gestation), from whom samples were collected before induction of labour. METHODS: Urocortin and CRF measurements by radioimmunoassay; digital palpatory cervical examination and Bishop score computation; cervical length and funnelling presence assessment by transvaginal ultrasonography. RESULTS: Maternal plasma CRF concentrations were significantly (P < 0.05) lower whilst those of urocortin were unchanged in post-term compared with term pregnancy. However, CRF and urocortin levels were both significantly (P < 0.05 and P < 0.001 respectively) higher in pregnancies delivered within 12 h of labour induction than in those that remained undelivered, and were significantly correlated with the induction-delivery interval (CRF: r = -0.676, P = 0.0015; urocortin: r = -0.783, P < 0.0001). CONCLUSIONS: CRF and urocortin levels are decreased and unchanged, respectively, in post-term pregnancy when compared with term pregnancy. Both CRF and urocortin correlate with the time of labour onset after induction. Since CRF derives from the placenta, and urocortin from the fetus, the concerted expression of these neuropeptides appears to be relevant in determining the length of human gestation.

Nucleated red blood cells in uncomplicated prolonged pregnancy.

OBJECTIVE: Elevated counts of nucleated red blood cells (NRBCs), as well as prolongation of pregnancy, have been suggested as predictors of adverse perinatal outcome. However, the association between these 2 variables has received only minimal attention. We sought to evaluate fetal NRBCs in prolonged pregnancies. METHODS: Umbilical cord blood was prospectively collected at delivery from 75 prolonged (at or beyond 287 days) pregnancies. One hundred and fifty term deliveries (260-286 days) served as controls. All pregnancies were accurately dated with the use of first-trimester sonography. Fetal biophysical profile testing was initiated at 40 weeks of gestation. Patients were delivered if they were in spontaneous labor or the biophysical profile was nonreassuring or by 42 weeks of gestation. Nucleated red blood cell counts were expressed per 100 white blood cells (WBC). Umbilical artery pH studies, as well as other demographic and clinical variables, were obtained. RESULTS: Prolonged pregnancy was associated with a significantly increased incidence of induction of labor and a greater birth weight. There were no other differences between the study group and controls. The median NRBCs per 100 WBCs in prolonged pregnancy was not significantly elevated over the term values (median 3, range 0-35 versus median 3, range 0-34, respectively; P =.25). Neonatal outcome was also comparable between groups. The univariate regression analysis demonstrated a significant association between elevated NRBC counts and low arterial cord blood pH (P <.008, R = 0.175), elevated base excess (P =.02, R = 0.149), low platelet counts (P =.046, R = 0.134), and male gender (P =.028). Stepwise regression analysis revealed that low arterial cord blood pH and male gender were the only independent variables predicting elevated NRBC counts at birth. CONCLUSION: The findings of this study suggest that elevated NRBC counts are associated with specific pregnancy complications rather than uncomplicated prolonged pregnancies in general.

Maternal serum levels of dehydroepiandrosterone sulfate and labor induction in postterm pregnancies.

OBJECTIVES: To study the relationship between maternal endogenous dehydroepiandrosterone sulfate (DHEAS) levels, success of labor induction, and Bishop scores in postterm pregnancies. METHODS: There were 65 postterm pregnancies. Group 1 consisted of women spontaneously in the active phase of labor, and group 2 of women with hypotonic uterine contractions whose labor was inducted by oxytocin. Levels of DHEAS were studied from venous blood samples. Demographic data and Bishop scores were recorded. RESULTS: The demographic characteristics of patients were similar, but DHEAS levels were higher in group 1 than in group 2 (P<0.001). Linear regression analysis showed a significant relationship between DHEAS and Bishop scores. DHEAS levels in women delivered vaginally were significantly higher than in women delivered by cesarean section. From the receiver operating characteristics (ROC) curve, DHEAS levels might determine the mode of delivery and success of labor induction; however, Bishop scores do not. CONCLUSIONS: DHEAS levels may be an important factor influencing the efficiency of labor and the success of labor induction in postterm pregnancies.

Is the correlation between fetal oxygen saturation and blood pH sufficient for the use of fetal pulse oximetry?

OBJECTIVES: Fetal pulse oximetry was performed during labor in high-risk cases for fetal distress to determine the diagnostic value of this method. METHODS: The fetal SpO2 values were blinded from the obstetrician so that these values did not influence clinical decisions. Mean and lowest SpO2 measurements for the last 30 min prior to either fetal scalp blood sampling or delivery were correlated with scalp pH or pH from the umbilical artery. RESULTS: No significant correlation was found between pH and mean fetal oxygen saturation (correlation coefficient -0.02, p = 0.9). There was no significant correlation between pH and lowest fetal oxygen saturation (correlation coefficient 0.04, p = 0.84). Concerning the feasibility of the method, we found that only 23 of 65 included patients were suitable for analysis; in 20% of cases, we were not able to perform a SpO2 measurement. CONCLUSIONS: None of three cases with pH below 7.05 would have been detected using mean SpO2 over the last 30 min prior to fetal scalp blood sampling or delivery. Only one case would have been detected using the lowest SpO2 measurement over this period. We conclude that fetal SpO2 measurements during labor are of poor diagnostic value, with a disappointing feasibility and therefore are not ready for implementing into daily clinical practice.

Elevated umbilical cord plasma erythropoietin levels in prolonged pregnancies.

OBJECTIVE: To determine if umbilical cord plasma erythropoietin levels are elevated in pregnancies that continue beyond their expected date for delivery. METHODS: Erythropoietin was measured using an enzyme-linked immunosorbent assay in 124 appropriately grown newborns delivered from 37-43 weeks' gestation. Each woman had an uncomplicated labor and delivery course without evidence of fetal stress or meconium. The comparison was made between pregnancies ending at 37-40 weeks' gestation and those at 41-43 weeks' gestation. RESULTS: There was no difference between the two groups in cord blood gases or Apgar scores at 1 and 5 minutes. Cord plasma erythropoietin levels were significantly higher in pregnancies delivered after 41 completed weeks' gestation (41 or more weeks: 48.0+/-7.1 mIU/mL, n=45 versus 37-40 weeks: 26.1+/-4.2 mIU/mL, n=79, P < .001). When compared with pregnancies delivered between 37 and 40 weeks, erythropoietin levels were significantly elevated in pregnancies delivered at either 41, 42, or 43 weeks' gestation. CONCLUSION: In pregnancies reaching 41 weeks and beyond, cord plasma erythropoietin levels are significantly increased, indicating altered fetal oxygenation in some of these pregnancies. These results support the current practice of close fetal surveillance of prolonged pregnancies.

Hemodynamic, hematological and hemorrheological evaluation of post-term pregnancy.

OBJECTIVE: To evaluate the hemorrheological modifications in post-term pregnant women. METHODS: Pregnant women (n = 48) at > 280 days' gestation, were tested on alternate days by nonstress test; ultrasound assessment of amniotic fluid volume, placental grading, hourly measurement of fetal urine production, and maternal fetal Doppler analysis. We further recorded maternal: plasma viscosimetry, red blood cells, hemoglobin, hematocrit, platelet count, mean platelet volume, fibrinogen, antithrombin III, creatinine, uric acid, plasma calcium, hPL, and estriol. We analyzed the last values obtained within 48 hours prior to delivery. RESULTS: The subjects were divided into Group I (40 wks to 40 wks+3 days; n = 16); Group II (40 wks+4 days to 41 wks; n = 16); Group III (> 41 wks; n = 16). The time-averaged maximum velocity of the fetal descending thoracic aorta was lower at Doppler analysis in Group III (29.0 +/- 3.5 cm/s) than in Group I (34.0 +/- 4.3 cm/s; p < 0.05). A decrease of the middle cerebral/umbilical pulsatility index ratio (1.75 in the Group I vs 1.52 in the Group III; p < 0.05) was shown. Furthermore, the incidence of oligohydramnios; Grannum placental grade III; plasma viscosity and coagulation parameters were significantly higher in Group III patients. The plasma viscosity resulted positively correlated with uric acid, and inversely correlated with fibrinogen, antithrombin III and platelet number values. CONCLUSIONS: From the present data we conclude that post-term pregnancy may mimic a mild 'fetal growth restriction'.

[Prolonged pregnancy and trace elements: iron]. / Prenosena bremennost i mikroelementi: zheliazo.

Iron is an essential trace element and it is well known that the iron requirement steadily increase during pregnancy. The aim of this investigation was to compare the serum iron levels in normal and serotine pregnancy. Twenty-six women with serotine pregnancy (19 in 42 and 7 in 43 gestation week (g.w.)) were included in the study. The control group is consisted from 74 women with normal pregnancy. The serum iron concentration is elevated in the women with serotine pregnancy (24.59 +/- 11.60 mmol/(l), but the difference was not significant. The group with serotine pregnancy in 42 g.w. has even lower serum iron concentration than the women with normal pregnancy (19.44 +/- 6.52 mmol(l). The serum iron concentration was significantly elevated (p < 0.001) in serotine pregnancy in 43 g.w. compared with normal pregnancy as well as with serotine pregnancy in 43 g.w. The possible pathogenetic mechanisms of the observed changes are discussed.