Is preeclampsia associated with an increased risk of cesarean delivery if labor is induced?

Objective.?To determine whether preeclampsia is associated with an increased risk of cesarean delivery if labor is induced.

Methods.?This retrospective cohort study of 3505 women ≥24 weeks gestation with singleton pregnancies undergoing labor induction compares cesarean delivery rates between preeclamptics and non-preeclamptics. Multivariable logistic regression analysis was used to control for potential confounders including unfavorable cervix (Bishop score ≤5), method of labor induction, maternal age, parity, gestational age, race/ethnicity, epidural use, medical insurance, and marital status.

Results.?Among term nulliparous women undergoing labor induction, preeclamptics had a higher cesarean delivery rate then non-preeclamptics (81/267, 30% vs. 363/1568, 23%; p?=?0.011), as did preeclamptic compared with non-preeclamptic women who were term and multiparous (10/64, 16% vs. 55/900, 6%, p?=?0.003). Preterm preeclamptics also had more cesarean deliveries compared with non-preeclamptics among nulliparous (48/164, 29% vs. 16/245, 7%; p?<?0.001) and multiparous (13/72, 18% vs. 18/225, 8%; p?=?0.015) women. In multivariable analysis, preeclampsia still conferred an increased risk of cesarean delivery if labor was induced (adjusted odd ratio?=?1.90, 95% CI 1.45–2.48).

Conclusion.?Women with preeclampsia undergoing labor induction had higher cesarean delivery rates compared with non-preeclamptics regardless of parity or gestational age. However, the majority of women with preeclampsia still had successful vaginal deliveries.     

Does epidural analgesia prolong labor and increase risk of cesarean delivery? A natural experiment

OBJECTIVE: More than 50% of pregnant women in the United States are using epidural analgesia for labor pain. However, whether epidural analgesia prolongs labor and increases the risk of cesarean delivery remains controversial. STUDY DESIGN: We examined this question in a community-based, tertiary military medical center where the rate of continuous epidural analgesia in labor increased from 1% to 84% in a 1-year period while other conditions remained unchanged-a natural experiment. We systematically selected 507 and 581 singleton, nulliparous, term pregnancies with spontaneous onset of labor and vertex presentation from the respective times before and after the times that epidural analgesia was available on request during labor. We compared duration of labor, rate of cesarean delivery, instrumental delivery, and oxytocin use between these two groups. RESULTS: Despite a rapid and dramatic increase in epidural analgesia during labor (from 1% to 84% in 1 year), rates of cesarean delivery overall and for dystocia remained the same (for overall cesarean delivery: adjusted relative risk, 0.8; 95% confidence interval, 0.6-1.2; for dystocia: adjusted relative risk, 1.0; 95% confidence interval, 0.7-1.6). Overall instrumental delivery did not increase (adjusted relative risk, 1.0; 95% confidence interval, 0.8-1.4), nor did the duration of the first stage and the active phase of labor (multivariate analysis; P >.1). However, the second stage of labor was significantly longer by about 25 minutes (P <.001). CONCLUSION: Epidural analgesia during labor does not increase the risk of cesarean delivery, nor does it necessarily increase oxytocin use or instrumental delivery caused by dystocia. The duration of the active phase of labor appears unchanged, but the second stage of labor is likely prolonged. (Am J Obstet Gynecol 2001;185:128-34).     

Is a change in the vaginal flora associated with an increased risk of preterm birth?

OBJECTIVE: The purpose of this study was to determine if a change in the vaginal flora was associated with an increased risk of preterm birth, and to determine if metronidazole therapy before 32 weeks increased the risk of preterm birth. STUDY DESIGN: We compared cultures taken at 23 to 26 weeks of gestation with cultures taken at delivery from women enrolled in the Vaginal Infections and Preterm Birth study to analyze the association of changes in the vaginal flora with preterm birth. RESULTS: Metronidazole therapy before 32 weeks was associated with an increased risk of preterm birth (OR 1.5, 95%CI 1.05-2.1) in an unadjusted model. A change to heavy growth of Escherichia coli or Klebsiella pneumoniae at delivery was found to be associated with preterm birth (OR 2.4, 95%CI 1.6-3.8). After controlling for race, parity, prepregnancy weight <100 pounds, smoking or drinking during pregnancy, Trichomonas vaginalis, bacterial vaginosis, chlamydia, mycoplasmas, group B streptococcus, metronidazole therapy before 32 weeks, vaginal pH >5.0, and an increase in E coli or K pneumoniae , only prepregnancy weight <100 pounds (adjusted odds ratio [AOR] 2.07, 95%CI 1.01-4.21) and increased E coli or K pneumoniae in the vagina at delivery (AOR 2.99, 95%CI 1.37-6.53) were found to be significantly associated with preterm birth. CONCLUSION: An increase in E coli or K pneumoniae in the vagina is an independent risk factor for preterm birth. Changes in the vaginal flora may explain the increased risk of preterm birth seen with vaginal clindamycin or oral metronidazole therapy.     

Does an inflatable obstetric belt facilitate spontaneous vaginal delivery in nulliparae with epidural analgesia?

OBJECTIVE: To assess whether an inflatable obstetric belt, synchronised to apply uniform fundal pressure during a uterine contraction, reduces operative delivery rates when used in the second stage of labour. DESIGN: Randomised controlled trial. METHODS: Five hundred nulliparae with a singleton cephalic pregnancy at term and with an epidural in labour were recruited during the first stage and randomised at full dilatation. Standard care involved one hour passive second stage and one hour active pushing after which instrumental delivery was performed if delivery was not imminent. Those randomised to the belt group, in addition to standard care, had the inflatable obstetric belt for the whole second stage of labour. MAIN OUTCOME MEASURE: Mode of delivery. RESULTS: One hundred and eleven of the 260 women in the belt group (42.7%) compared with 94 of the 240 in the control group (39.2%) had a spontaneous vertex delivery (P = 0.423). The lift-out instrumental delivery rate was similar between the two groups: 108 belts (41.5%), compared with 101 controls (42.1%) (P = 0.902), whereas rotational instrumental deliveries in the belt group were 26 belts (10%) compared with 36 controls (15%) (P = 0.09). Fifteen women (5.8%) in the belt group and nine women (3.8%) in the control group had a caesarean section in the second stage (P = 0.292). An intact perineum was more likely in the belt group (16.5% compared with 9.6%, P = 0.022) as was a third degree tear (6.5% compared with 0.4%, P = 0.001). CONCLUSION: The inflatable obstetric belt did not significantly reduce operative delivery rates when used in this clinical setting in the second stage of labour.     

Does an inflatable obstetric belt facilitate spontaneous vaginal delivery in nulliparae with epidural analgesia?

Objective To assess whether an inflatable obstetric belt, synchronised to apply uniform fundal pressure during a uterine contraction, reduces operative delivery rates when used in the second stage of labour.
Design Randomised controlled trial.
Methods Five hundred nulliparae with a singleton cephalic pregnancy at term and with an epidural in labour were recruited during the first stage and randomised at full dilatation. Standard care involved one hour passive second stage and one hour active pushing after which instrumental delivery was performed if delivery was not imminent. Those randomised to the belt group, in addition to standard care, had the inflatable obstetric belt for the whole second stage of labour.
Main outcome measure Mode of delivery.
Results One hundred and eleven of the 260 women in the belt group (42.7%) compared with 94 of the 240 in the control group (39.2%) had a spontaneous vertex delivery (   P = 0.423  ). The lift-out instrumental delivery rate was similar between the two groups: 108 belts (41.5%), compared with 101 controls (42.1%) (   P = 0.902  ), whereas rotational instrumental deliveries in the belt group were 26 belts (10%) compared with 36 controls (15%) (   P = 0.09  ). Fifteen women (5.8%) in the belt group and nine women (34%) in the control group had a caesarean section in the second stage (   P = 0.292  ). An intact perineum was more likely in the belt group (16.5% compared with 9–6%,   P = 0.022  ) as was a third degree tear (6.5% compared with 0.4%,   P = 0.001  ).
Conclusion The inflatable obstetric belt did not significantly reduce operative delivery rates when used in this clinical setting in the second stage of labour.     

Is human myometrial sampling at the time of cesarean delivery safe?

OBJECTIVE: The mechanism for the initiation of human labor remains unknown and is under extensive investigation. Myometrium from patients in labor and not in labor is the ideal tissue to study structural, cellular, and molecular changes that occur during parturition. This study was designed to determine whether myometrial sampling at the time of cesarean delivery increases maternal morbidity. STUDY DESIGN: This is a prospective cohort study including 118 study and 236 control patients. A full-thickness myometrial sample was obtained from the superior edge of a transverse uterine incision at the time of cesarean delivery. Demographics and standard surgical morbidity data were collected. Statistical methods used included univariate and multivariate analysis. RESULTS: The study and control groups did not differ significantly with respect to age, gravidity, parity, birth weight, and Apgar scores. The estimated intraoperative blood loss was greater in the control group (P <.02); however, the change in hematocrit level (preoperative vs postoperative values) was not different. There were no significant differences in the rates of endometritis, wound infection, and venous thrombosis up to 6 weeks post partum. When study and control patients were stratified into term in labor, term not in labor, preterm in labor, and preterm not in labor categories and compared for maternal morbidity, there were still no significant differences for any of the outcome measures evaluated. CONCLUSION: On the basis of our data, human myometrial sampling at cesarean delivery does not increase overall maternal morbidity, irrespective of gestational age and the presence or absence of labor.     

Vaginal delivery after Misgav–Ladach cesarean section – Is the risk of uterine rupture acceptable?

Objective.?To evaluate whether the single-layer closure as is a routine by the Misgav–Ladach method compared to the double-layer closure as used by the Dörfler cesarean method is associated with an increased risk of uterine rupture in the subsequent pregnancy and delivery.

Methods.?The analysis is retrospective and is based on medical documentation of the Clinic for Gynecology and Obstetrics, University Clinical Centre, Tuzla, Bosnia and Herzegovina. All patients with one previous cesarean section who attempted vaginal birth following cesarean section were managed from 1 January 2002 to 31 December 2008. Exclusion criteria included multiple gestation, greater than one previous cesarean section, previous incision other than low transverse, gestational age at delivery less than 37 weeks and induction of delivery. We identified 448 patients who met inclusion criteria.

Results.?We found that 303 patients had a single-layer closure (Misgav–Ladach) and 145 had a double-layer closure (Dörffler) of the previous uterine incision. There were 35 cases of uterine rupture. Of those patients with previous single-layer closure, 5.28% (16/303) had a uterine rupture compared to 13.11% (19/145) in the double-layer closure group (p?<?0.05).

Conclusion.?We have not found that a Misgav–Ladach cesarean section method (single-layer uterine closure) might be more likely to result in uterine rupture in women who attempted a vaginal birth after a previous cesarean delivery. This cesarean section method should find its confirmation in everyday clinical practice.     

Is early-pregnancy proteinuria associated with an increased rate of preeclampsia in women with pregestational diabetes mellitus?

OBJECTIVE: The purpose of this study was to determine whether the rate of preeclampsia in pregnant diabetic women is increased in those women with early-pregnancy proteinuria of 190 to 499 mg/24 hours compared with women with proteinuria of <190 mg/24 hours. STUDY DESIGN: Secondary analysis was performed with relevant data from 194 pregnant women with type 1 and type 2 diabetes mellitus whose condition required insulin and who were enrolled previously in a multicenter trial of low-dose aspirin for the prevention of preeclampsia. The women were assigned to 1 of 3 groups, based on the level of proteinuria at enrollment (13-26 weeks of gestation). Group 1 comprised women with <190 mg protein/24 hours (n=94); group 2 comprised women with 190 to 499 mg protein/24 hours (n=35); and group 3 comprised women with >/=500 mg protein/24 hours (n=65). The rate of preeclampsia, according to strict predefined criteria, was then determined. RESULTS: The rate of preeclampsia was not increased statistically significantly in patients with early-pregnancy proteinuria of 190 to 499 mg/24 hours (7/35 women; 20%) when compared with women with proteinuria of <190 mg/24 hours (16/94 women; 17%). CONCLUSION: We did not find an increased rate of preeclampsia in women with pregestational diabetes mellitus with early-pregnancy proteinuria of 190 to 499 mg/24 hours when compared with women with pregestational diabetes mellitus with proteinuria of <190 mg/24 hours.     

Labor pain and its management with the combined spinal–epidural analgesia: what does an obstetrician need to know?

Most women rate pain of childbirth as the most painful experience of their lives. Lumbar epidural analgesia is widely considered as the most effective method of providing pain relief in labor. However, lumbar epidural analgesia for labor is not a standard (generic) procedure and many technical modifications have been developed and introduced into clinical practice over time. The combined spinal–epidural labor analgesia technique (CSEA) has attained wide spread popularity in obstetric anesthesia worldwide. The onset of analgesia is rapid and reliable, and maternal satisfaction is very high. While there still remains some concern about dural puncture, and while the pros and cons of using the CSEA as opposed to traditional epidural for labor pain are still being debated, it appears certain that the CSEA technique offers many unique advantages to the pregnant woman.     

Is increased maternal endotelin-1 concentration associated with neonatal asphyxia and preterm delivery in intrahepatic cholestasis of pregnancy?

Objectives  

To evaluate plasma endothelin-1 (ET-1) and fetuin-A concentrations in women with intrahepatic cholestasis of pregnancy (ICP) and to determine whether there is any association between these parameters and fetal asphyxia.     

Is vaginal birth after cesarean less expensive than repeat cesarean delivery?

OBJECTIVE: This study was undertaken to compare total medical costs of trial of labor after cesarean with those of elective repeat cesarean without labor, with both short- and long-term neonatal costs associated with such procedures taken into account. STUDY DESIGN: Costs associated with All Patient Refined diagnosis-related groups and Current Procedural Terminology for a large not-for-profit health care system were applied to an algorithm describing maternal and neonatal outcomes of trial of labor. Perinatal morbidity rates and cost estimates for long-term neurologic damage associated with uterine rupture were derived from published literature. RESULTS: If a 70% vaginal birth rate for women undergoing a trial of labor and delivery in a tertiary center with a mean uterine rupture to delivery time of 13 minutes is assumed, the net cost differential ranged from a saving of $149 to a loss of $217, depending on morbidity assumptions. For vaginal birth after cesarean success rates <70%, trial of labor in the presence of two previous scars, and institutional factors increasing the perinatal morbidity rate by just 4% with respect to that seen in tertiary centers, trial of labor resulted in a net financial loss to the health care system regardless of all other assumptions made. CONCLUSIONS: When costs as opposed to charges are considered and the cost of long-term care for neurologically injured infants is taken into account, trial of labor after previous cesarean is unlikely to be associated with a significant cost saving for the health care system. Recent government-mandated length-of-stay requirements are likely to make the economic benefit of vaginal birth after cesarean even less favorable. Factors other than cost must govern decisions regarding trial of labor or repeat cesarean.     

Is maternal smoking during pregnancy associated with an increased risk of congenital heart defects among offspring? A systematic review and meta-analysis of observational studies

Objective: To investigate the association between maternal smoking during pregnancy and risk of congenital heart defects (CHDs) among offspring.

Methods: PubMed, EMBASE, and Web of Science were searched for eligible studies. The outcomes of interest included risk of any CHD and nine subtypes. We summarized study characteristics and used a random-effects model in meta-analysis, and a two-stage dose–response model was utilized to assess the association between smoking consumption and risk. Statistical heterogeneity was assessed by a chi-squared test of the Cochrane Q statistic and I-squared value. Publication bias was assessed by funnel plots and Egger’s test, and trim and fill method was utilized when publication bias existed.

Results: Forty-three observational epidemiologic studies were included. The pooled risk ratio (RR) of any CHD was 1.11 (95% CI: 1.04, 1.18), but it exhibited substantial statistical heterogeneity (p?I^2?=^?69.0%). In sensitivity analysis, we observed significant associations for atrial septal defect (ASD) and marginally significant associations for septal defects (SPD). The two-stage dose–response analysis showed evidence to support that higher levels of tobacco smoke was associated with an increased risk of septal defects, particularly for ASD and VSD (ventricular septal defect).

Conclusion: Our study presents evidence to support the cardiovascular teratogenic effect of maternal smoking during pregnancy, and their offspring may suffer from approximately a 10% relative increase in the risk of CHDs on average.     

Do women with polycystic ovary syndrome have an increased risk of cardiovascular disease? Review of the evidence

Polycystic ovary syndrome (PCOS) is a reproductive endocrine disorder found in ~5% of the general population and is characterized by chronic anovulation, hyperandrogenism, and insulin resistance. Women with PCOS are at increased risk for the development of Type II diabetes and may represent a unique group of women at high risk for the development of coronary heart disease (CHD). More adverse CHD risk profiles of women with PCOS have been demonstrated in several studies, yet actual health outcome studies have been inconclusive as to whether this translates into increased rates of cardiovascular disease in PCOS cases when compared to controls. This review focuses on the controversy surrounding the potential relationship between cardiovascular disease outcomes and polycystic ovary syndrome.