Outcome of pregnancy in a woman with an increased body mass index

OBJECTIVE

To show the increased risk of adverse outcomes in labour and fetomaternal morbidity in obese women (BMI > 30).

DESIGN

A population-based observational study.

SETTING

University Hospital of Wales. The study sample was drawn from the Cardiff Births Survey, a population-based database comprising of a total of 60,167 deliveries in the South Glamorgan area between 1990 and 1999. Population Primigravid women with a singleton uncomplicated pregnancy with cephalic presentation of 37 or more weeks of gestation with accurate information regarding height and weight recorded at the booking visit (measured by the midwives) were included in the study.

METHODS

Comparisons were made between women with a body mass index of 20-30 and those with more than 30. SPSS version 10 was used for statistical analysis. Student's t test, chi(2) and Fisher's exact tests were used wherever appropriate.

MAIN OUTCOME MEASURES

Labour outcomes assessed were risk of postdates, induction of labour, mode of delivery, failed instrumental delivery, macrosomia and shoulder dystocia. Maternal adverse outcomes assessed were postpartum haemorrhage, blood transfusion, uterine and wound infection, urinary tract infection, evacuation of uterus, thromboembolism and third- or fourth-degree perineal tears. Fetal wellbeing was assessed using Apgar <7 at 5 minutes, trauma and asphyxia, cord pH < 7.2, babies requiring neonatal ward admissions, tube feeding and incubator.

RESULTS

We report an increased risk [quoted as odds ratio (OR) and confidence intervals CI)] of postdates, 1.4 (1.2-1.7); induction of labour, 1.6 (1.3-1.9); caesarean section, 1.6 (1.4-2); macrosomia, 2.1 (1.6-2.6); shoulder dystocia, 2.9 (1.4-5.8); failed instrumental delivery, 1.75 (1.1-2.9); increased maternal complications such as blood loss of more than 500 mL, 1.5 (1.2-1.8); urinary tract infections, 1.9 (1.1-3.4); and increased neonatal admissions with complications such as neonatal trauma, feeding difficulties and incubator requirement.

CONCLUSION

Obese women appear to be at risk of intrapartum and postpartum complications. Induction of labour appears to be the starting point in the cascade of events. They should be considered as high risk and counselled accordingly.

Reference ranges for umbilical and middle cerebral artery pulsatility index and cerebroplacental ratio in prolonged pregnancies

OBJECTIVE

To construct normal ranges for umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI) and cerebroplacental ratio (CPR) in prolonged pregnancies according to strict methodological criteria using polynomial regression analysis.

METHODS

This was a retrospective, cross-sectional observational study involving 140 women, 10 women for each gestational day between 287 and 300 days of gestation. Fetal Doppler parameters were assessed to construct normal reference ranges for UA PI and MCA PI. CPR was calculated as a ratio of MCA PI/UA PI.

RESULTS

Mathematical modeling of the data demonstrated that the optimal fit was a linear polynomial one. Mean, 5th and 95th centiles were calculated for UA, MCA and CPR and centile curves from the regression analysis were constructed.

CONCLUSIONS

Reference ranges for UA PI, MCA PI and CPR in prolonged pregnancies have been constructed. MCA PI shows a wider range than previously reported in the literature.

Skewed fetal gender distribution in prolonged pregnancy: a fallacy with consequences

OBJECTIVE

Skewed gender distribution and falsely assigned gestational age lead to unnecessary or late obstetric intervention in prolonged pregnancy. The aim of this study was to examine the consequences of a fetal gender-dependent systematic 1.5-day dating error at ultrasound fetometry.

MATERIAL AND METHODS

A total of 82 484 singleton deliveries >/=37 weeks at 11 hospitals in southern Sweden from 1995 to 2000 were included. Frequencies of labor induction and Apgar scores <7 at 5 min were compared with regard to fetal gender, both before and after correction of gestational age by adding 0.75 days to female-fetus pregnancies and subtracting 0.75 days from male-fetus pregnancies.

RESULTS

The uncorrected odds ratio for having a male baby at >/=42 weeks was 1.41 (95% confidence interval, 1.33-1.49). After adjusting gestational age by +/-0.75 days, the odds ratio reduced to 0.90 (95% confidence interval, 0.84-0.95). The risk for labor induction was significantly above unity in male-fetus pregnancies delivered after 41 weeks when gestational age was corrected for fetal gender, while the risk for female fetuses having a low Apgar score was not significantly increased compared to male fetuses (P = 0.087).

CONCLUSION

Skewed gender distribution in prolonged pregnancy results in a higher rate of labor induction in pregnancies with male fetuses at >/=41 weeks, and the risk for newborn females having a low Apgar score in prolonged pregnancy is not significantly increased compared to boys.

Postterm with favorable cervix: is induction necessary?

OBJECTIVE

To study the cesarean rate between expectant management and immediate induction in the otherwise uncomplicated postterm pregnancy with favorable cervix.

STUDY DESIGN

A total of 249 women with uncomplicated pregnancies at 41 weeks plus 3 days (290 days) with favorable cervix (Bishop score > or =6) were randomized to either expectant management (n=125) or immediate induction of labor (n=124). The women in the induction group were sent to labor ward for induction by artificial rupture of membranes (ARM) and/or oxytocin infusion. The women with expectant management had nonstress test (NST) and amniotic fluid index (AFI) performed once a week and twice a week after 43 weeks of gestation until spontaneous labor.

RESULTS

The cesarean rate was not different between expectant management and immediate induction (21.6% versus 26.6%; P=0.36). Ninety-five percent of the expectant group delivered within 1 week after enrollment, and all of them delivered within 9 days after randomization. Maternal and fetal complications in both groups were not different. There was also no difference in the mean birth weight (P=0.24) and the frequency of macrosomia (birth weight > or = 4000 g) between the two groups (P=0.23).

CONCLUSION

Cesarean section rate between expectant management and immediate induction in the otherwise uncomplicated postterm pregnancy with favorable cervix was not different. Due to the very low adverse perinatal outcome, both expectant management and immediate induction are acceptable.

The amniotic fluid index in late pregnancy

OBJECTIVE

Our purpose was to examine changes in the amniotic fluid index (AFI) in accurately dated term pregnancies both in relation to gestational age and in relation to the onset of spontaneous labor.

STUDY DESIGN

This was a prospective observational study in 137 women with uneventful term pregnancies, in whom 220 AFI measurements were performed. More than one AFI value was available from 51 individuals.

RESULTS

The AFI did not change significantly between 37 and 42 weeks' gestation, but a significant reduction was seen during the last 11 days before the spontaneous onset of labor (R = -0.37, n = 83, p < 0.001). The AFI (corrected for gestational age) within individuals remained stable over periods of up to 2 weeks. Meconium staining of the amniotic fluid was related to gestational age, but not to the AFI or fetal distress at birth. No significant correlation was found between fetal distress and the AFI, or between fetal distress and the reduction in AFI during the last two measurements before labor.

CONCLUSIONS

The reduction of the AFI in pregnancies progressing beyond term is related to the labor process itself rather than to the exact gestational age.

The effects of cardiovascular dynamics monitoring in the outpatient management of pregnancy hypertension

OBJECTIVE

Our purpose was to assess the effects of the adjunctive use of cardiovascular dynamics monitoring in the ambulatory management of 199 pregnant patients with severe hypertension.

STUDY DESIGN

A prospective, observational study was performed. Determinants of mean arterial pressure were computed by using the Hon monitor. Indicators of arterial compliance and effective blood volume were developed. All patients were monitored in the outpatient clinic; additionally, 19 patients self-tested at home. No rigid medication protocol was followed, but furosemide was used in most cases when cardiovascular dynamics monitoring patterns were consistent with volume loading. Otherwise, vasodilators were prescribed. The t test for independent samples was used to compare the home-monitored subgroup with the outpatient-only group.

RESULTS

Pregnancy was prolonged by 74 +/- 63.9 days (mean +/- SD). Mean gestation was 37.6 +/- 2.9 weeks, and mean birth weight was 2882.4 +/- 837 g. The primary cesarean delivery rate was 23.7%, but only 15 (7.5%) cesarean deliveries were performed because of failed therapy. The 19 home-monitored patients gained 108 +/- 75 days (83.1 +/- 42.2 days beyond 20 weeks).

CONCLUSION

Adjunctive cardiovascular dynamics monitoring may have a role in the evaluation and management of hypertension during pregnancy.

Changing obstetric practices associated with decreasing incidence of meconium aspiration syndrome

OBJECTIVE

To describe changes in neonatal and obstetric practices that may have contributed to the decreasing incidence of meconium aspiration syndrome in our population during this time.

METHODS

We compared neonatal and obstetric characteristics of 61 infants diagnosed with meconium aspiration syndrome with 1365 infants born through moderate or thick meconium-stained amniotic fluid at more than 37 weeks' completed gestation. Data were prospectively collected, and all respiratory diagnoses were concurrently made. Three distinct birth year groups were analyzed based on changing obstetric practice paradigms.

RESULTS

Meconium aspiration syndrome decreased nearly four-fold from 1990-1992 to 1997-1998 (5.8% to 1.5% of meconium-stained infants more than 37 weeks; P <.003). The only change in neonatal characteristics was a 33% decrease in births more than 41 weeks with a reciprocal 33% increase in births 38-39 weeks during 1997-1998. Significant changes in obstetric practice included more frequent diagnosis of nonreassuring fetal heart rate patterns, greater use of amnioinfusion, and increased cesarean delivery rate in 1997-1998. By logistic regression analysis, the only consistent risk factor for meconium aspiration syndrome across all three epochs was the presence of tracheal meconium.

CONCLUSION

Reduction in post-term delivery was the most important factor in reducing meconium aspiration syndrome.

Quantitative foetal fibronectin as a predictor of successful induction of labour in post-date pregnancies

OBJECTIVE

To study the relationship between induced labour, quantitative levels of fibronectin and the Bishop score.

STUDY DESIGN

Vaginal fibronectin/Bishop score were estimated in 33 nulliparous women undergoing induction of labour for post-dates at the Department of Obstetrics and Gynaecology, Guy's and St. Thomas' Hospital London.

RESULTS

There was no significant relationship between either the fibronectin level or Bishop score and the duration of the latent phase (R(2)=0.001; P=0.86 and R(2)=0.12; P=0.08, respectively). There was no relationship between the total prostaglandin dose and fibronectin level (R(2)=0.03; P=0.39) nor any significant correlation between either the Bishop score or fibronectin level and the induction to delivery time (R(2)=0.13; P=0.11 and R(2)=0.0006; P=0.97, respectively). Significant relationships were observed inversely between the total prostin dose and Bishop score (R(2)=0.33; P=0.002), between the total prostin dose and latent phase (R(2)=0.54; P=0.000009) and between Bishop score and the fibronectin levels (R(2)=0.19; P<0.01).

CONCLUSIONS

Quantitative foetal fibronectin is not a useful test for inducibility at term.

Correlation among amniotic fluid index (AFI), cesarean section rate, and labor length in inducted pregnancies beyond 41 weeks' gestation with unfavorable cervix

This paper evaluated how the pregnancy after 41 completed weeks' gestation with amniotic fluid index (AFI) > 6 has a slower response to the prostaglandin E2 (PGE2) induction. Eighty-one post-term pregnancies (41 completed gestations' weeks) with unfavorable cervix were considered in this follow-up. Induction was performed by means of intracervical PGE2 gel (Dinoprostone 0.5 mg). After 12 hours, if the cervix was still unfavorable, then another gel administration followed. Cases that had oxytocin administration were excluded from the study. The median time of spontaneous delivery in the overall series was 25 hours, 14 minutes. We had 18 cases of cesarean section (22.2%). In the group of pregnancies with AFI > 6 (60 cases) and in the group with AFI < or =6 (21 cases), the median time of spontaneous delivery was 29 hours, 25 minutes and 23 hours, 39 minutes, respectively (p-value = 0.02). The rate of cesarean sections was 26.67 and 9.52, respectively in the two groups (p-value >0.05). Two out of four cases of cesarean sections for fetal distress belonged to the group of AFI > 6. All the 14 cases of cesarean section for dystocia belonged to the group with AFI > 6. Considering just patients who did not deliver within 12 hours (57 cases), median time of spontaneous delivery was 33 hours and 24 hours 40 minutes for group AFI > 6 (42 cases) and AFI < or =6 (15 cases), respectively (p-value = 0.0009). Thirty-one cases out of 57 had another PGE2 gel administration. Adjusted odds ratio was 0.33 (0.16-0.65, 95% C.I.) for AFI < or =6 versus AFI > 6.

[The Doppler cerebroplacental ratios and perinatal outcome in post-term pregnancy]

Our purpose was to determine whether the Doppler cerebroplacental ratios predicts perinatal outcome in postterm pregnancy. The middle cerebral to umbilical artery resistant and pulsatility indices (MCA PI/UA PI and MCA RI/UA RI) were measured in 59 postterm pregnancies. We found significant correlation between MCA PI/UA PI, MCA RI/UA RI, nonstress testing and intrapartum fetal heart rate assessment. There was also an association between MCA PI/UA PI and 1- and 5-minute Apgar score. We conclude that the Doppler cerebroplacental ratios provide useful information about perinatal outcome.

[Prolonged pregnancy: apropos of a series of 102 cases]

It was a retrospective and continuous prospective study about 102 post-term pregnancy recensed on a 14 months period. The aim of this study is to evaluate our management of post term pregnancy and the peto-maternal morbidity and mortality.

RESULTS

Frequency of post-term pregnancy in our study is 5.92%, in rate of session sector is not higher it is of 18.62. There is no maternal mortality. Neonatal mortality is a about 19/1000, the rate of neonatal morbidity is 2.9%.

Receiver operating characteristic curves of ultrasonographic estimates of fetal weight for prediction of fetal growth restriction in prolonged pregnancies

OBJECTIVE

Recent studies have documented increased perinatal morbidity and mortality rates in the growth-restricted postterm fetus. Our purpose was to evaluate the receiver operating characteristic curve of ultrasonographically estimated fetal weight as a predictor of fetal growth restriction in prolonged pregnancies.

STUDY DESIGN

Fetal weight was estimated ultrasonographically within 9 days of delivery (mode 1 day) in members of a cohort of 410 patients with prolonged pregnancies (>41 weeks). Estimated fetal weights were compared with birth weights in receiver operating characteristic curve analysis.

RESULTS

The areas under the receiver operating characteristic curves for predicting birth weights <10th percentile (3125 g in this population) and <5th percentile (2930 g in this population) were 0.89 and 0.96, respectively. Both areas were significantly different from an area indicating a useless test. The estimated fetal weight values corresponding to the inflection points for the receiver operating characteristic curves predicting birth weights <10th percentile and <5th percentile were 3370 and 3200 g, respectively. With estimated fetal weight at less than these test cutoff values, the relative risks for a fetus to have a birth weight <10th percentile or <5th percentile were 14.6 (95% confidence interval, 6.25-33.8) and 89.8 (95% confidence interval, 12.1-665), respectively. Analysis of the receiver operating characteristic curves resulted in improved test characteristics relative to using the actual 10th and 5th birth weight percentiles as cutoff values for estimated fetal weight (relative risk of 14.6 vs 9.5 and 89.8 vs 26.0, respectively).

CONCLUSIONS

Ultrasonographic estimation of fetal weight is a useful test for predicting fetal growth restriction in prolonged pregnancies. Future studies should evaluate whether intervention on the basis of this identification results in improved perinatal outcome.

Influence of postdatism and meconium on fetal erythropoietin

OBJECTIVE

To determine whether fetal erythropoietin (Epo) concentrations are increased in pregnancies extending beyond 41 weeks' gestation and whether this is influenced by the presence of meconium-stained amniotic fluid.

METHODS

Epo concentrations were measured in 116 fetal umbilical cord blood samples from otherwise uncomplicated pregnancies between 37 to 43 weeks' gestation during the period of October 1996 to October 1997. An enzyme-linked immunosorbent assay kit was used to measure Epo. Maternal demographics and birth outcomes including Apgar score, cord blood pH, and base deficit were obtained. Fetuses born between 41 and 43 weeks' gestation (post-term) were compared with matched controls born between 37 and 40 weeks' gestation (term). In addition, both post-term and term fetuses with meconium-stained amniotic fluid were compared with matched controls without meconium.

RESULTS

Post-term fetuses without meconium had significantly higher Epo levels compared with term fetuses (mean +/- SEM: 50.6 +/- 6.5 versus 29.5 +/- 3.3 mIU/ml, p = 0.002). When matched for gestational age, fetuses with meconium-stained amniotic fluid had significantly greater Epo concentrations compared with controls without meconium (post-term, 80.7 versus 50.6 mIU/ml; term, 61.4 versus 29.5 mIU/ml; p < 0.05). However, no significant difference in Epo levels was found between post-term fetuses with meconium and term fetuses with meconium (80.7 +/- 15.7 mIU/ml versus 61.4 +/- 12.8 mIU/ml, respectively). Mean cord blood pH and base deficit values for all groups were within normal clinical range.

CONCLUSION

Cord blood Epo concentrations were significantly increased in pregnancies extending beyond 41 weeks. Irrespective of gestational age, meconium-stained amniotic fluid was associated with a significant rise in Epo. High Epo levels in these pregnancies imply subacute or chronic fetal hypoxia. Close clinical monitoring of post-term fetuses and those with meconium-stained amniotic fluid is warranted.

Prediction of oligohydramnios in prolonged pregnancy

A decrease in amniotic fluid in prolonged pregnancy is associated with increased fetal morbidity. However, few investigations have been reported on the prediction of this condition. Fetal renal arterial pulsatility index (PI), hourly fetal urine production rate (HFUPR) and amniotic fluid index (AFI) at 39 weeks were studied in 51 singleton pregnancies with (n = 14) and without oligohydramnios (AFI < 5, n = 37) in prolonged pregnancy. There was no difference in the average fetal renal arterial PI and HFUPR between the oligohydramnios group and the normal group. However, the average AFI in the oligohydramnios group was 7.5 +/- 0.9, which was lower than that in the normal group (p < 0.05). We speculated that AFI value at 39 weeks is useful for predicting the incidence of oligohydramnios in prolonged pregnancy.

[Prolonged ovarian pregnancy: a case report]

OBJECTIVES

Case of advanced ovarian pregnancy are exceptional because ovarian pregnancy itself is very rare.

STUDY DESIGN

The authors describe a case of prolonged ovarian pregnancy with retention of the dead fetus for more than a year. Usually ovarian pregnancy finishes in rupture which occurs before the end of the first trimester. It is then difficult to make out the integrity of the organs and in particular of the tube and indeed to recognize them. On the other hand when the mass persists intact with the development of pregnancy in a retort shape, it is easy to see how confusion is possible and arises between it and an intra-uterine pregnancy. In this case, however, the different anatomical forms are clear and an almost definite diagnosis can be made at the time of operation (the three first criteria of Spiegelberg). The diagnosis of ovarian pregnancy is never made before operation. At the very best one can say, when things happen early, that an extra-uterine pregnancy has ruptured, or in certain particular circumstances like in the case we are reporting lithopedian. The presence of ovarian tissue in the wall of the sac, which is the fourth criterion of Siegelberg, is easier to recognize in early accidents than in advanced cases of ovarian pregnancy in which the parenchyma of the ovary is compressed, distended and laminated by the increasing development of the fetus and the adnexae. The absence of the placenta being adherent to other organs than the ovary can then be kept as a worthwhile criterion of ovarian pregnancy.

Management of pregnancies beyond forty-one weeks' gestation with an unfavorable cervix

OBJECTIVE

Our purpose was to determine the optimal management of pregnancies beyond 41 weeks' gestation with a cervix unfavorable for induction.

STUDY DESIGN

All uncomplicated pregnancies that reached 41 weeks' gestation with a Bishop score of < or = 4 were randomly assigned to one of three groups: (1) daily cervical examinations, (2) daily membrane stripping, or (3) daily placement of prostaglandin gel until 42 weeks.

RESULTS

In 105 pregnancies the Bishop score on admission to labor and delivery was significantly greater in the groups receiving prostaglandin or stripping of the membranes versus the control group, whereas the converse was time of gestational age at delivery (p = 0.0001). Fewer patients required induction in the two treatment groups (20%, 17%) versus the control (69%) patients (p < 0.0001).

CONCLUSIONS

Daily membrane stripping or daily placement of prostaglandin gel is successful in reducing the number of inductions at 42 weeks for postdatism.

Association between a low umbilical artery pulsatility index and fetal distress in labor in very prolonged pregnancies

OBJECTIVE

To investigate the association between fetal, umbilical and uterine circulatory changes and adverse perinatal findings in very prolonged pregnancies.

STUDY DESIGN

44 women proceeding to 43 completed weeks of gestation with the intention of a trial of vaginal delivery were studied prospectively with ultrasound Doppler velocimetry. An intensified fetal surveillance was routinely commenced at 42 weeks and only uncomplicated pregnancies were allowed to proceed. The endpoint perinatal measures were oligohydramnios, fetal meconium release, fetal distress in labor and birth asphyxia. Flow variables in different groups were compared with the Mann-Whitney U test, Student's unpaired t-test, Wilcoxon signed-rank matched-pairs test, Fisher's exact test and contingency table analysis, and a two-tailed P value <0.05 was considered statistically significant.

RESULTS

The umbilical artery pulsatility index was significantly lower in cases of fetal meconium release (n=12) and fetal distress (n=7). The umbilical venous flow velocity was significantly lower in cases of meconium, and the fetal aortic volume flow significantly higher in cases of fetal distress. No significant flow changes were found in connection with oligohydramnios (n=5) and birth asphyxia (n=2). Uterine flow was not significantly affected in any group.

CONCLUSIONS

In very prolonged pregnancies, fetal distress in labor was not associated with an increased placental vascular resistance. In contrast to previous reports, the umbilical artery pulsatility index was low in cases of fetal distress and meconium release. The etiology is unknown, but a subclinical fetal hypoxia might have triggered a vasodilation of placental vessels. Vasodilation at an unchanged volume flow could also explain the decrease of umbilical venous flow velocity. The increased aortic volume flow indicates an increase of cardiac output in fetuses later developing distress in labor.

Motoric responses to sucrose in postmature and term infants

Postmature infants calm less when presented with sucrose solutions than term infants. To further assess the influence of postmaturity on sucrose responsivity, several motoric responses were examined in healthy term neonates and chronically stressed postmature (> or = 288 days gestational age (GA) e.g., > 41 weeks) neonates with Clifford's Syndrome tested between 5-91 h of age. Following baseline observations, each subject was presented with 0.1 ml of a 14% sucrose solution for 10 s each min for 5 min, and observations were continued for 5 min following stimulation. During sucrose stimulation and poststimulation phases, postmature infants showed more tremors during quiet state than term infants. Across conditions, postmature infants exhibited increased finger sucking, rhythmic sucking, but less mouth opening and arm movements than healthy, term infants. Sequence analysis revealed that short-latency mouthing, repetitive movements of the upper and lower lips, followed sucrose infusion reliably in postmature infants, but not term infants. These results suggest that postmaturity is associated with: 1. Increased oral behaviors associated with arousal and self soothing; and 2. Increased sucrose reactivity, as indicated by contingent mouthing and increased tremors.

[Term pregnancy: the review and development of fetal surveillance protocols]

The authors have analyzed the reasons behind the changes in clinical and biophysical monitoring of term and post-term pregnancies. In particular, there is an assessment of the results of NST monitoring over a one-year period. Furthermore, the importance of the introduction of new methods of labour induction by means of intracervical PGE2 is also discussed and there is a reference to the results. It is clinically evident that these methods have contributed to modify the problem of term-pregnancy management. Finally, there is a presentation of the new version of up-to-date procedures based on more clinical experience and more recent statistics on the subject.

Is oligohydramnios in postterm pregnancy associated with redistribution of fetal blood flow?

OBJECTIVE

Our purpose was to determine whether postterm patients with oligohydramnios differ in their fetal and umbilical blood flow distribution from those with a normal volume of amniotic fluid.

STUDY DESIGN

Pulsed-wave Doppler imaging was used prospectively to determine the resistance index in the fetal middle cerebral, renal, and umbilical arteries in 57 postterm (i.e., > 41 weeks' gestation) pregnancies. Semiquantitative assessment of amniotic fluid volume was obtained by use of the ultrasonographically determined amniotic fluid index.

RESULTS

Oligohydramnios (amniotic fluid index < 5 cm) was detected in 15 patients; 42 patients with a normal amniotic fluid index served as a control group. The various resistance index values and the ratio s among them were not significantly different when patients with oligohydramnios were compared with controls (0.51 +/- 0.1 vs 0.52 +/- 0.06, 0.63 +/- 0.1 vs 0.64 +/- 0.08, and 0.71 +/- 0.08 vs 0.73 +/- 0.05 for the umbilical, middle cerebral, and renal arteries, respectively). However, the mean birth weight (in grams) was significantly lower (3297 +/- 438 vs 3742 +/- 448, p < 0.003), in the oligohydramnios group.

CONCLUSION

Oligohydramnios was not associated with a major redistribution of blood flow in postterm patients, suggesting that the cause of oligohydramnios in these patients is related to birth weight rather than to renal perfusion.

[Verification of KTG recording in states of perinatal partial asphyxia using fetal capillary blood pH]

We analysed 91 cases of pH-metric verifications of pre-pathological and pathological cardiotocograms, which suggested imminent perinatal partial asphyxia. In 50% of cases there was no need for medical intervention, this groups of patients delivered vaginally and newborns were in good condition. In 80% pH value well correlated with state of newborn at birth. Pre-pathological cardiotocograms showed mainly variable decelerations, pH value didn't show acidosis and afterbirth umbilical cord collision was stated. In pathological cardiotocograms we observed mainly late decelerations, pH value showed fetal acidosis which coexisted with placental insufficiency in prolonged gestation.

Doppler flow velocimetry of the umbilical artery, uteroplacental arteries and fetal middle cerebral artery in prolonged pregnancy

A total of 153 pregnant women, of at least 287 days' menstrual age, were studied in a prospectively designed cross-sectional trial. In addition to the non-stress test, contraction stress test, sonographic estimate of amniotic fluid and grade of placental maturation, Doppler measurements of the resistance index (RI) were taken in the umbilical artery, the uteroplacental arteries in the region of placental implantation and the fetal middle cerebral artery. Data were analyzed with regard to asphyxia and otherwise complicated fetal outcome. Furthermore, a possible relationship between grade of placental maturation, Doppler flow velocity waveforms and fetal outcome was investigated. Doppler resistance indices in the umbilical artery, uteroplacental arteries in the region of placental implantation and fetal middle cerebral artery did not change significantly with increasing gestation from 41 to 43 weeks. The grade of placental maturation on ultrasound examination was not related to fetal outcome or Doppler indices in the first two vessels. In all vessels examined in this study, the majority of Doppler measurements in pregnancies with subsequent asphyxia or otherwise complicated fetal outcome were within the 95% prediction interval for patients with normal fetal outcome. None of the patients showed absent diastolic flow in the umbilical artery. With the use of a cut-off value of RI = 0.62 in the umbilical artery, asphyxia could be predicted with 37% sensitivity and 75% specificity. Oligohydramnios and antpartum cardiotocography predicted asphyxia with 16% and 8% sensitivity and 95% and 96% specificity, respectively. Sensitivity for prediction of otherwise complicated fetal outcome by umbilical artery Doppler was only 7%.(ABSTRACT TRUNCATED AT 250 WORDS)

Longitudinal measurement of amniotic fluid index in postterm pregnancies and its association with fetal outcome

OBJECTIVE

Our purpose was to study the association between dynamic changes in serial amniotic fluid index measurements and adverse fetal outcome in postterm pregnancies.

STUDY DESIGN

Serial amniotic fluid index values were obtained semiweekly in 139 reliably dated, uncomplicated, singleton pregnancies at > 41 weeks' gestation. Adverse fetal outcome was defined by the presence of moderate or thick meconium, fetal heart rate decelerations, cesarean delivery for fetal distress, neonatal intensive care unit admission, and perinatal mortality.

RESULTS

Prominent changes in the amniotic fluid index (i.e., > 50% increase or decrease) had no association with adverse fetal outcome irrespective of rate of change, provided the final value remained > 5.0 cm. A significant association with fetal heart rate decelerations and the presence of meconium was detected only in patients whose final amniotic fluid index was < or = 5.0 cm (p = 0.007 and p = 0.003, respectively).

CONCLUSION

Irrespective of the rate of change in amniotic fluid index, postterm pregnancies are significantly associated with potential complications such as fetal heart rate decelerations and meconium staining when the final amniotic fluid index is < or = 5.0 cm.

Prolonged gestation, decreased triiodothyronine concentration, and thyroid gland histomorphologic features in newborn foals of mares grazing Acremonion coenophialum-infected fescue

Newborn foals of mares grazing on Acremonium coenophialum-infected fescue pasture throughout gestation or from gestation day 300 to parturition had increased gestation duration and decreased serum triiodothyronine concentration. Pregnant mares were allotted to 4 treatments: grazing continuously on endophyte-free (E-) fescue, grazing continuously on endophyte-infected (E+) fescue, grazing on E+ fescue from gestation day 300 to parturition, and grazing on E+ fescue from conception to gestation day 300. Morphometric studies indicated that foals born to mares exposed to endophyte late in gestation had large, distended thyroid follicles lined by flat cuboidal epithelial cells. Mean triiodothyronine concentration in foals exposed to endophyte (395.2 ng/dl) was decreased (P < 0.01), compared with mean values in control foals (778.0 ng/dl). Thyroxine and reverse triiodothyronine concentrations were not significantly different among groups. Foal organ weight as a percentage of foal body weight was not significantly different among experimental groups.

[Prolonged pregnancy--prostaglandins as the cause of labor onset]

The causes of prolonged pregnancy are still largely unknown and their investigation requires a detailed observation of potential birth-initiating stimuli on the endocrine and biomolecular level. A large number of clinical and biochemical studies point to the central importance of prostaglandins for the beginning of human birth. The main places of origin of the intensified prostaglandin formation and release are the amnion and the decidua which has "macrophage-like" properties and functions. The superordinate regulation and trigger mechanisms for intensified uterine prostaglandin production has not been sufficiently investigated either. Possible factors currently being debated include local changes in estrogen and progesterone biosynthesis in fetal membranes and decidua, subclinical inflammatory reactions with the activation of macrophages and the consecutive release of cytokines, and a loss of maternal immune tolerance with a time-determined rejection reaction. In addition, the substances inhibiting and stimulating prostaglandin synthesis have been detected in the amniotic fluid, fetal membranes and decidua. The fetus itself also plays an important part in the initiation of labor. Prolongation may be due to anatomic functional disturbances of the one hand which prevent the activation of the fetal hypothalamic-hypophyseal-adrenal axis and the release of the birth-initiating stimuli originating in the fetus; on the other hand, an elevated immune tolerance with a delayed rejection reaction or the lack of "bacterial stimulus" may inhibit the activation of the macrophages and hence the formation of cytokines. The consequences would be the development and release of a quantity of prostaglandins from the fetal membranes and decidua insufficient to overcome the pregnancy-maintaining safety systems.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of post-term pregnancy: to induce or not?

Perinatal mortality is increased in pregnancies over 42 weeks, but can be reduced by the induction of labour. However, clinicians must consult with the patient as to whether she would rather experience spontaneous onset of labour or accept this increased risk. This article weighs up the important considerations in this difficult area.

[Doppler findings--placental morphology: correlation and divergence of findings]

Based on 132 histomorphological placental investigations and their related Doppler test results, the question was asked, whether a strong correlation exists between Doppler test results and histomorphological placenta results, and whether these are uniform with respect to histomorphological changes. The results showed that all histomorphologically inconspicuous placenta findings were also inconspicuous doppler-sonographically. The viewing resulted in no histomorphologically unifying aspect of change. However, the investigation was able to demonstrate, that a distinction must be made between acutely developing changes and chronically developing changes. Along these lines, the last groups produced not only changes which compensate each other, but also changes, which are harmful to organic functioning and thus may diminish foetal supply without being detected by pulsed Doppler ultrasound.

Post-term pregnancies with normal cardiotocographs and amniotic fluid columns: the role of Doppler evaluation in predicting perinatal outcome

OBJECTIVE

To study the role of Doppler ultrasound examination in predicting an abnormal perinatal outcome, among post-term pregnancies uncomplicated by an abnormal non-stress test (NST) or reduced amount of amniotic fluid.

DESIGN

A prospective study.

SETTING

High-risk pregnancy unit, Hadassah Mt. Scopus University Hospital, Jerusalem.

SUBJECTS

Seventy-eight women with confirmed gestational age of > 287 days, who had normal initial evaluation and unfavourable cervical examination.

INTERVENTIONS

Doppler flow velocity waveforms were recorded from the umbilical and middle cerebral arteries, and from the descending thoracic aorta.

MAIN OUTCOME MEASURES

Correlation between Doppler measurements and data regarding delivery.

RESULTS

Women who developed signs of fetal distress during labour, or who required intervention because of fetal distress, had elevated umbilical artery systolic/diastolic ratio, decreased middle cerebral artery pulsatility index, and decreased time average aortic blood flow velocity. Umbilical artery Doppler measurements could significantly predict the need for intervention due to fetal distress.

CONCLUSIONS

Doppler examination of uncomplicated post-term pregnancies may identify patients with normal results as having a low risk of developing fetal distress during labour. Patients with abnormal Doppler results are prone to need intervention following fetal distress in labour.

[Development of Doppler parameters in fetal and maternal blood vessels 10 days before to 10 days after the calculated due date]

Doppler sonography can help to assess a foetal risk situation prospectively. This procedure is therefore well suited for the screening of risk pregnancies in the 3rd trimenon. The role of Doppler ultrasound at delivery is still controversial, since, on the one hand, no data on the behaviour of Doppler parameters directly at the onset of delivery are available, and on the other hand the obstetric consequences from pathological findings are not clear. For this reason, we observed 45 normal pregnancies from the 10th day prior to the date of confinement till the 10th day post partum. In 20 patients we registered Doppler parameters from 4 days before until the onset of true labour. In all these cases, a reduction of the end-diastolic blood flow in the foetal aorta was found, which became evident by the increase of the resistance index to pathological values. Concomitant decrease of the resistance index in the foetal carotid artery was typical for a circulatory system. Since foetal outcome was normal in all newborn, this change in Doppler parameters directly at the beginning of labour must be considered as physiological. The findings suggest a physiological placental insufficiency. Since however, parameters in the uterine vessels did not show any changes, the insufficiency has its probable origin in the placenta. From these findings, one might speculate, that the supply deficiency is the labour inducing factor. No clinical consequence can thus result from pathological Doppler data found in patients directly prior and after delivery. Cardiotocographic screening is necessary.(ABSTRACT TRUNCATED AT 250 WORDS)

Fetal renal pulsed Doppler waveform in prolonged pregnancies

OBJECTIVE

Our purpose was to determine Doppler waveforms of the fetal human renal artery in prolonged pregnancy in the presence or absence of oligohydramnios.

STUDY DESIGN

Fifty patients at or after 40 weeks were studied. Ultrasonography was performed to determine the amniotic fluid index by the four-quadrants technique. Two groups of patients were obtained on the basis of the amniotic fluid index. Group 1 had an amniotic fluid index > 5 (normal) (n = 33); group 2 had amniotic fluid index < or = 5 (oligohydramnios) (n = 17). Umbilical artery and fetal renal pulsed Doppler waveforms were determined and analyzed. The fetal renal artery systolic-to-diastolic ratio of the two groups was compared.

RESULTS

Fetuses with a low amniotic fluid index had a significantly higher ratio. A significant negative correlation coefficient between amniotic fluid index and fetal renal systolic/diastolic ratio was found (r = -0.435 and p < 0.01).

CONCLUSIONS

In prolonged pregnancies there is a significant relationship between the amniotic fluid index and the fetal renal systolic/diastolic ratio. In pregnancies associated with oligohydramnios the systolic/diastolic ratio is significantly higher than in those with normal amniotic fluid volume. These data suggest that intrarenal flow in prolonged pregnancies complicated with oligohydramnios is significantly different.

[Doppler ultrasound diagnosis in post-term pregnancy]

The capability of Doppler flow velocimetry to predict intrauterine growth retardation is well known. The increased morbidity and mortality rate of postterm newborns is also well known. The aim of our study was to examine if Doppler flow velocimetry is able to indicate foetal jeopardy in the postterm period. Flow velocimetry of the foetal descending aorta, the umbilical artery, the uterine arteries and in 59 cases also the foetal middle cerebral artery was obtained from 167 pregnancies after 40 completed weeks of gestation. We found significant changes of normal values in prolonged pregnancy compared to third trimester normal values, examining the mean velocity of the foetal descending aorta and the S/D-ratio of the umbilical artery. No clinically significant changes were found examining the S/D-ratio of the uterine arteries and the pulsatility index of the foetal middle cerebral artery. Daily examinations of the foetal descending aorta were carried out in 23 and of the umbilical artery in 19 cases during the last four days before delivery, and in 11 cases of the foetal middle cerebral artery during the last three days before delivery. We did not find significant changes in the medians of the mean velocity of the foetal aorta, of the S/D-ratio of the umbilical artery and of the pulsatility index of the foetal middle cerebral artery. Measurement of sensitivity and positive predictive value of the four arteries examined showed, that Doppler ultrasound could not predict small for date infants or Caesarean section because of foetal distress.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniotic fluid volume estimation in the postdate pregnancy: a comparison of techniques

OBJECTIVE

To determine the amniotic fluid (AF) volume estimation technique with the greatest diagnostic value with respect to perinatal outcome in the postdate pregnancy.

METHODS

One hundred ninety-eight women who were at least 40 weeks' gestation based on ultrasound confirmation or establishment of dates were evaluated twice weekly with nonstress tests (NSTs) and AF volume estimation. Various indices of AF volume were measured and correlated with perinatal outcome. Receiver operating characteristic curves were used to determine optimal cutoff values.

RESULTS

There was a significantly larger maximal vertical pocket in those pregnancies with a normal perinatal outcome than in those with abnormal outcome (4.2 +/- 1.4 versus 3.2 +/- 2.0 cm; P = .02). A statistically significant difference was also seen with the AF index (10.0 +/- 4.5 versus 7.5 +/- 5.0 cm; P = .01). Analysis revealed that the optimal cutoff for identifying clinically significant oligohydramnios was a largest vertical pocket less than 2.7 cm, with an adjusted odds ratio for abnormal perinatal outcome of 7.11 (95% confidence interval [CI] 2.79-18.16). Its sensitivity of 50.0% and specificity of 87.9% were superior to the diagnostic value of the AF index of 5 cm, which had a sensitivity of 29.2% and specificity of 89.1%.

CONCLUSION

A largest vertical pocket threshold of 2.7 cm had the greatest diagnostic value for identifying the postdate pregnancy at risk for abnormal perinatal outcome, surpassing the AF index and the 2-cm largest vertical pocket rule.

The value of Doppler ultrasonography in prolonged pregnancies

One hundred forty-two gravid women at term were followed prospectively by a non-stress test, estimation of amniotic fluid volume and Doppler velocimetry of the umbilical and uterine arteries. Adverse perinatal outcome was detected in 12 women (8.5%). Abnormal antepartum tests were detected in 26 women (17%). Seven women had an abnormally elevated resistance index (RI) in the umbilical artery; but only two had an abnormal outcome. Seven women had an abnormally elevated RI in the uterine artery, but only two had abnormal outcome. Three out of 11 women with oligohydramnion had abnormal perinatal outcome. Only one out of seven women with an abnormal non-stress test had abnormal perinatal outcome. In six women, more than one antepartum test was abnormal. The various surveillance methods demonstrated a low sensitivity (the highest was obtained by estimating amniotic fluid volume: 25%) and a low positive predictive value (the highest obtained by measuring the resistance index in either the umbilical or the uterine arteries: 28.6%). By considering any abnormal test as a positive test result for a given patient, a substantial improvement in sensitivity (66.7%) and positive predictive value (33.3%) are obtained. Doppler velocimetry adds very little in itself to the follow-up of patients with post-term gestations. However, when combined with additional antepartum tests, it may increase our ability to predict the compromised fetus in this condition.

Clinical significance of fetal heart rate patterns during labor. IX: Prolonged pregnancy

The intrapartum FHR and UC were recorded in a population of 707 consecutive cases of prolonged gestation looking for a characteristic pattern. There is no typical pattern for prolonged pregnancy. However, there are differences from preterm and term populations. There is a very high incidence of variable (55%) and late (17%) decelerations. These were seen more frequently among cases receiving oxytocin. Nearly 50% of C-sections had lates. Baseline alterations (tachycardia 26%, fixed 8%, and saltatory 17%) were often associated. Apgar scores < or = 6 at 1 minute were correlated with variable and late decelerations. However, acidemia (UA pH < or = 7.20) could not be predicted from FHR patterns because there was no correlation between low pH and clinical depression. Alarmingly a few fetuses in agonal state presented normal appearing tracings, or deteriorated rapidly without the usual indicative changes by FHR. All intrapartum or NND had this misleading pattern. In view of this unpredictable aberrant pattern as the only certain means to prevent these deaths, it is suggested that no pregnancy should be allowed to reach 294 days post LMP.

[Determination of birth date by early ultrasonography]

Ultrasound examination has become an indispensable tool in antenatal care. In cases with intrauterine growth retardation, post-term pregnancy and when deciding elective delivery, knowledge about gestational age is essential. However, criticism has been raised against its routine use to determine gestational age. Ultrasound is subject to a certain degree of variation, as is determination of gestational age on the basis of the last menstrual period. Variation is less by ultrasound, which therefore reduces the number of "post-term" pregnancies. The consequences of post-term pregnancy are discussed.

Prospective evaluation of the contraction stress and nonstress tests in the management of post-term pregnancy

Eight hundred and nineteen patients were evaluated at greater than or equal to 280 days' gestation. All patients underwent nonstress test (NST) and breast stimulation to induce contraction stress test (CST), except where contraindicated. If CST was nonqualifying (less than three contractions per ten minutes), Pitocin (oxytocin) was used to complete the CST if there was a nonreactive NST. Delivery was instituted for any abnormal CST, even with a reactive NST, based on the last test within seven days of delivery. There were 747 reactive NST and 72 nonreactive NST. Breast stimulation for CST was done in 655 instances--315 (48 per cent) had nonqualifying CST and 340 (52 per cent) had qualifying CST. There was an increased incidence of induction in the nonqualifying CST group and abnormal CST group. There were no statistically significant differences in perinatal outcomes in the group with reactive NST, irrespective of the CST result. There were no antepartum fetal deaths.

The effect of hypothalamic lesions on the length of gestation in fetal sheep

Twenty-nine sheep fetuses were subject to stereotaxic surgery at 106 to 110 days of gestation. Electrolytic lesions were placed bilaterally in the anterior hypothalamus. Sham-operated controls (n = 4) were delivered at 146.3 +/- 4.3 days. Of the fetuses with lesions, two were excluded because histologic confirmation of the lesion was not possible. Those fetuses with bilateral lesions of the suprachiasmatic nuclei (n = 4) were delivered at 148 +/- 10 days. In 10 animals with bilateral lesions of the paraventricular nuclei, delivery was significantly (p less than 0.0001) prolonged to at least 165.6 +/- 5.1 days. In nine animals with lesions not involving the endocrine hypothalamus, delivery was at 148.1 +/- 4.3 days. All animals that were delivered after 157 days (n = 9) had lesions including the paraventricular nuclei bilaterally (p less than 0.01). The adrenal glands of fetuses with prolonged gestation were normal in weight and light microscopic appearance. These observations demonstrate that fetal neural pathways involving the paraventricular nuclei are essential for parturition in the sheep. However, fetal adrenal growth can continue without such influences.

Placental lactogen secretion during prolonged-pregnancy in the rat: the ovary plays a pivotal role in the control of placental function

The serum of rats at mid-pregnancy contains at least 2 distinct placental lactogen (PL)-like substances tentatively termed placental lactogen-alpha (PL-alpha) and placental lactogen-beta (PL-beta) (Endocrinol Japon 38: 533-540, 1991). We have investigated the secretory patterns of three placental lactogens (PL-alpha, PL-beta and placental lactogen-II) during normal pregnancy and in two prolonged-pregnancy models. Pregnancy was prolonged by the introduction of new corpora lutea by inducing ovulation on day 15 of pregnancy by successive treatments with PMSG (30 IU/rat, sc on day 12) and hCG (10 IU/rat, iv on day 14), and in the second model by progesterone implants on day 15 of pregnancy. During normal pregnancy, each of the 3 PLs exhibited only one secretory peak in the serum; PL-alpha and PL-beta on day 12 and placental lactogen II (PL-II) on day 20. Interestingly, in the rats with new sets of corpora lutea, serum PL-alpha and PL-beta levels began to increase again on day 18 and showed peaks on day 20 for PL-alpha and on day 22 for PL-beta. In this model, the initiation of PL-II secretion was not affected, but high levels were maintained until day 26, when parturition occurred. In rats receiving either PMSG or hCG, the secretory patterns of the PLs were similar to as those during normal pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Doppler evaluation of umbilical and uterine-arcuate arteries in the postdates pregnancy

To assess the correlation between Doppler velocimetry and perinatal outcome in the postdates pregnancy, 75 women who were at least 41 weeks' gestation were evaluated twice weekly until delivery. Evaluation included Doppler velocimetry of the umbilical and uterine-arcuate arteries, as well as nonstress testing and amniotic fluid volume estimation. The mean umbilical artery systolic-diastolic ratio (S/D) was significantly higher in the pregnancies with subsequent abnormal perinatal outcomes than in those with normal outcomes (2.42 versus 2.19; P = .03). Using a receiver operating characteristic curve, an abnormal umbilical artery S/D was defined as 2.40 or greater. Using this value, sensitivity was 57.1% and specificity was 77.8%. Our study suggests that an umbilical artery S/D of 2.40, rather than the more traditionally accepted cutoff of 3.0, may be a useful threshold to identify those postdates pregnancies at high risk for abnormal perinatal outcome.

[Ultrasound Doppler sonography in obstetrics. A comparison between simple Doppler methods (continuous or pulsed Doppler) and the duplex system (combination of B-image and pulse Doppler)]

120 pregnant women between the 26th and 42nd week of gestation have been examined using simple Doppler-units with pulsed- or continuous-wave technique and duplex Doppler-units (combined B-mode and pulsed-wave Doppler). The umbilical and uterine arteries were measured with both units in a semi-recumbent position at the same time by the same examiner. Only ideal flow profiles were taken to calculate the S/D-ratio. Our results were correlated to the fetal outcome, to all cases of pre-eclampsia and to all cases of intra-uterine growth retardation. Except in one of these cases we got the majority of pathological results using simple Doppler-units. Only in pre-eclampsia the duplex Doppler-units had the majority of pathological results. Even in normal fetal outcome the majority of simple Doppler-unit results are pathological. This finding is due to the impossibility to localize the vessel exactly using simple Doppler-units. Sensitivity is higher in simple Doppler-techniques (74.3% to 52.9%), specificity is higher in duplex Doppler-technique (77.9% to 52.6%).

Doppler flow velocity waveform analysis in postdate pregnancies

This study examines the efficiency of Doppler flow velocity waveform analysis in the evaluation of the postdate pregnancy. Seventy women whose pregnancies were at or beyond 41 weeks' gestation were assessed by calculating the systolic/diastolic ratios from umbilical and uteroplacental arteries. Waveform ratios from pregnancies associated with fetal compromise and abnormal neonatal outcome were similar to those from pregnancies in which the outcome was normal. These findings indicate that the pathophysiology of placental insufficiency in postdate pregnancies differs from that observed in cases of fetal growth retardation at earlier gestational ages. Doppler flow velocity waveform analysis is unlikely to be of benefit in the routine assessment of the postdate pregnancy.