PubMed Health⌕ Search

Biomedical subjects

Baha M Sibai

Publications and source records attributed to Baha M Sibai.

At least 19 recordsLinked to original sources

Thrombophilia and adverse maternal-perinatal outcome: controversies in screening and management.

A recent review of the literature on thrombophilia and adverse pregnancy outcome reveals contradictory findings. There are retrospective and prospective studies that recommend testing for genetic and acquired markers of thrombophilia for those with the enumerated adverse pregnancy outcome. Based on our review, routine screening for thrombophilias in women with a history of adverse pregnancy outcome (preeclampsia, abruptio placenta, intrauterine growth restriction, and fetal loss) is not justified. Based on data from observational studies and few randomized trials with inadequate number of subjects, there is consensus that women with true antiphospholipid antibody syndrome should receive low-dose aspirin plus adjusted-dose heparin in subsequent pregnancies. Some authors also recommend heparin prophylaxis in subsequent pregnancies in women with genetic thrombophilia with previous adverse pregnancy outcome. However, this recommendation is not based on randomized trials. Hence, a randomized double-blind, controlled trial is urgently needed to evaluate the benefit of heparin during pregnancy in women with a history of adverse pregnancy outcome in association with genetic thrombophilia.

Abruptio Placentae↗

Soluble endoglin and other circulating antiangiogenic factors in preeclampsia.

BACKGROUND: Alterations in circulating soluble fms-like tyrosine kinase 1 (sFlt1), an antiangiogenic protein, and placental growth factor (PlGF), a proangiogenic protein, appear to be involved in the pathogenesis of preeclampsia. Since soluble endoglin, another antiangiogenic protein, acts together with sFlt1 to induce a severe preeclampsia-like syndrome in pregnant rats, we examined whether it is associated with preeclampsia in women. METHODS: We performed a nested case-control study of healthy nulliparous women within the Calcium for Preeclampsia Prevention trial. The study included all 72 women who had preterm preeclampsia (<37 weeks), as well as 480 randomly selected women--120 women with preeclampsia at term (at > or =37 weeks), 120 women with gestational hypertension, 120 normotensive women who delivered infants who were small for gestational age, and 120 normotensive controls who delivered infants who were not small for gestational age. RESULTS: Circulating soluble endoglin levels increased markedly beginning 2 to 3 months before the onset of preeclampsia. After the onset of clinical disease, the mean serum level in women with preterm preeclampsia was 46.4 ng per milliliter, as compared with 9.8 ng per milliliter in controls (P<0.001). The mean serum level in women with preeclampsia at term was 31.0 ng per milliliter, as compared with 13.3 ng per milliliter in controls (P<0.001). Beginning at 17 weeks through 20 weeks of gestation, soluble endoglin levels were significantly higher in women in whom preterm preeclampsia later developed than in controls (10.2 ng per milliliter vs. 5.8 ng per milliliter, P<0.001), and at 25 through 28 weeks of gestation, the levels were significantly higher in women in whom term preeclampsia developed than in controls (8.5 ng per milliliter vs. 5.9 ng per milliliter, P<0.001). An increased level of soluble endoglin was usually accompanied by an increased ratio of sFlt1:PlGF. The risk of preeclampsia was greatest among women in the highest quartile of the control distributions for both biomarkers but not for either biomarker alone. CONCLUSIONS: Rising circulating levels of soluble endoglin and ratios of sFlt1:PlGF herald the onset of preeclampsia.

Antigens, CD↗

The MFMU Cesarean Registry: impact of time of day on cesarean complications.

OBJECTIVE: Studies suggest that sleep deprivation adversely affects performance. We hypothesized that cesarean delivery complications would be more frequent during the night shift (11 pm-7 am), and evaluated morbidities by delivery shift. STUDY DESIGN: Eighteen thousand nine hundred and thirty-nine term women undergoing an unscheduled cesarean delivery in 13 centers from 1999 to 2000 within a prospective observational study were included. Maternal/neonatal morbidities and time from decision to cesarean delivery were evaluated by time of delivery (7 am-3 pm, 3 pm-11 pm, 11 pm-7 am). A composite of maternal morbidities was evaluated by logistic regression controlling for potentially confounding factors. RESULTS: Controlling for age, race, insurance, cardiac disease, preeclampsia, diabetes, previous incision type, and prenatal care, shift of delivery had no impact on maternal morbidity (11 pm-7 am OR 0.9 [95% CI 0.81-1.0]). NICU admissions were slightly increased at night but neonatal complications were not. CONCLUSION: Maternal and neonatal complications of cesarean delivery do not increase with delivery during the night shift.

Adult↗

A prospective masked observational study of uterine contraction frequency in twins.

OBJECTIVE: This study was undertaken to compare uterine contraction frequency in twins versus singletons and to determine if contraction frequency can be an efficient predictor of spontaneous preterm birth in twin gestations. STUDY DESIGN: Fifty-nine twin and 306 singleton gestations were enrolled between 22 and 24 weeks at 11 centers. Contraction frequency was recorded with a home uterine activity monitor (HUAM) 2 or more times per day on 2 or more days per week until delivery or 36-6/7 weeks. Masked HUAM data were interpreted according to standard protocol. Repeated measures analyses were used to determine whether mean or maximum uterine contraction frequency per hour differed between singleton and twin gestations across gestational age, by time of day, and by delivery before 35 weeks or beyond. Uterine contraction frequency was also evaluated by logistic regression and receiver operator characteristic (ROC) curves as tests to predict spontaneous preterm birth. RESULTS: There were 34,908 hours of HUAM data recorded by the 306 singleton gestations and 5,427 hours by the 59 women with twins. Uterine contraction frequency was significantly greater in twins (P = .002) compared with singletons, regardless of gestational age. Contraction frequency in twins increased significantly with gestational age and time of day (1600-0359 hours); but was not associated with spontaneous preterm birth. Maximum uterine contraction frequency was associated with preterm birth less than 35 weeks but only in the morning (am) recording (0400-1559) and at the 29- to 30-week gestational age interval. This relationship was modest (odds ratio 1-2) and not consistent across gestational age or between the am and afternoon/evening (pm) monitoring sessions. ROC analysis revealed no contraction frequency that efficiently identified twins who delivered prematurely at any 2-week gestational age interval. CONCLUSION: Mean uterine contraction frequency was significantly higher for twin gestations than singletons throughout the latter half of pregnancy and between 1600 and 0359 hours but was not higher among twins who delivered less than 35 weeks' gestation. Neither maximum am or pm contraction frequency predicted spontaneous preterm birth less than 35 weeks' gestation in twin pregnancies.

Adult↗

Shared and disparate components of the pathophysiologies of fetal growth restriction and preeclampsia.

Intrauterine growth restriction (IUGR) and preeclampsia differ in their association with maternal disease but share a similar placental pathology. Moreover, mothers who have had pregnancies complicated by preeclampsia or IUGR are at elevated later-life cardiovascular risk. Why, then, do some women develop IUGR and others develop preeclampsia? In this clinical opinion, based on a review of the literature, we hypothesize that both women experiencing preeclampsia and IUGR enter pregnancy with some degree of endothelial dysfunction, a lesion that predisposes to shallow placentation. In our opinion, preeclampsia develops when abnormal placentation, through the mediator of elevated circulating cytokines, interacts with maternal metabolic syndrome, comprised of adiposity, insulin resistance/hyperglycemia, hyperlipidemia, and coagulopathy. IUGR develops in the absence of antenatal metabolic syndrome. Among these women, the baby is affected by shallow placentation but the mother does not develop clinically apparent disease. This conceptualization provides a testable framework for future etiologic studies of preeclampsia and IUGR.

Animals↗

Tocolysis in women with preterm labor between 32 0/7 and 34 6/7 weeks of gestation: a randomized controlled pilot study.

OBJECTIVE: The purpose of this study was to determine whether intravenous magnesium sulfate (MgSO4) followed by oral nifidepine tocolysis in women with preterm labor between 32 0/7 and 34 6/7 weeks' gestation reduces neonatal hospital stay. STUDY DESIGN: Fifty-four women between 32 0/7 and 34 6/7 weeks with preterm labor were randomized to receive either MgSO4 and oral nifidepine (n = 24) or no tocolysis (n = 30). All women received betamethasone and prophylactic antibiotics. The primary outcome was total neonatal hospital stay. Data were analyzed using Chi-square and Mann Whitney U test. RESULTS: The 2 groups had similar mean cervical dilation and gestational age at enrollment. There were no statistically significant differences in total neonatal hospital stay (5.8 +/- 7.2 days; median of 3 days in the no tocolysis vs. 7.5 +/- 8.6 days; median of 3 days in the tocolysis group), rate of preterm delivery (57% vs. 75%) or need for oxygen supplementation (7% vs. 21%, p < 0.23). The neonatal complications were similar in each group. CONCLUSION: Tocolysis after 32 weeks gestation does not reduce neonatal hospital stay.

Adult↗

The MFMU Cesarean Registry: impact of fetal size on trial of labor success for patients with previous cesarean for dystocia.

OBJECTIVE: The purpose of this study was to determine the influence of change in infant birth weight between pregnancies on the outcome of a trial of labor for women whose first cesarean delivery was performed for dystocia. STUDY DESIGN: Secondary analysis of 7081 patients with 1 previous cesarean delivery and no other deliveries after 20 weeks' gestation, undergoing a trial of labor with a singleton gestation. Cases were classified as dystocia if the listed indication for the cesarean delivery in the first pregnancy was failed induction, cephalo-pelvic disproportion, failure to progress, or failed forceps or vacuum. Outcomes of the trial of labor were correlated with fetal size relative to birth weight in the initial pregnancy for those women whose initial cesarean delivery was for dystocia and those with other indications. RESULTS: For the cohort being studied (n = 7081), dystocia was the indication for the first cesarean delivery for 3182 (44.9%). Trial of labor resulted in vaginal delivery for 54% of patients whose first cesarean delivery was performed for dystocia, compared with 67% for those with other indications (P < .01). For those whose first cesarean delivery was for dystocia, trial of labor success was correlated with birth weight differences between the pregnancies, with only 38% delivering vaginally if the trial of labor birth weight exceeded the initial pregnancy birth weight by more than 500 g. Using logistic regression and adjusting for other potential confounding factors, the odds of success decreased by 3.8% for each increase of 100 g in birth weight in the trial of labor relative to the first birth weight. CONCLUSION: For women with previous cesarean delivery for dystocia, increasing birth weight in the subsequent trial of labor relative to the first birth weight diminishes the chances of successful vaginal delivery.

Adult↗

Preeclampsia as a cause of preterm and late preterm (near-term) births.

Gestational hypertension-preeclampsia is the most common medical disorder of pregnancy. It is also a major cause of maternal and perinatal morbidities. The majority of adverse pregnancy outcomes occur in patients who develop severe hypertension or severe preeclampsia, and in those who develop the clinical manifestations before 34 weeks' gestation. There is some concern regarding neonatal morbidity in the late preterm (near term) infant (34 0/7 through 36 6/7 weeks' gestation) as a result of gestational hypertension and preeclampsia. A review of the available data suggests that most deliveries of the late preterm infant in such women are justified because of the concerns about maternal and fetal safety with continued gestation. In addition, the rate of preterm delivery at 34 to 36 weeks' gestation in women with gestational hypertension or preeclampsia is low. Indeed, most admissions to Neonatal Intensive Care Unit in such pregnancies occur in those at > or =37 weeks' gestation. There is urgent need for research to assess the reasons behind preterm delivery at 34 to 36 weeks' gestation in women with hypertension and preeclampsia. In addition, there is need for research to assess the reasons for admission to the NICU in term infants born of mothers with varying severities of hypertension and preeclampsia. In this paper, the phrase "late-preterm" has been used instead of "near term," as the former was considered more appropriate to reflect this subgroup of preterm infants in a workshop on this topic held in July 2005, organized by the National Institute of Child Health and Human Development.

Female↗

Preeclampsia: Diagnosis and management of the atypical presentation.

Preeclampsia, eclampsia, and HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome remain as major obstetric problems that plague a large percentage of women resulting in an equally large percentage of maternal and perinatal morbidities. It is important that a clinician makes the most accurate diagnosis possible to prevent these adverse maternal and perinatal outcomes. In general, most women will have a classical presentation of preeclampsia (hypertension and proteinuria) at >20 weeks gestation and <48 hours postpartum. However, recent studies have suggested that some women will develop preeclampsia without the classical findings. The purpose of this review is to increase awareness of the non-classical and atypical features of preeclampsia, eclampsia, and HELLP syndrome and their respective management. Atypical cases are those that develop before 20 weeks, beyond 48 hours postpartum and those that present with some of the signs and symptoms of preeclampsia without the usual hypertension or proteinuria. By formulating a rational stepwise approach towards diagnosis, we may prevent the costly consequence of a missed diagnosis and its eventual possible fatalities.

Diagnosis, Differential↗

Trial of labor or repeat cesarean delivery in women with morbid obesity and previous cesarean delivery.

OBJECTIVE: Assess effects of body mass index (BMI) on trial of labor after previous cesarean delivery and determine whether morbidly obese women have greater maternal and perinatal morbidity with trial of labor compared with elective repeat cesarean delivery. METHODS: Secondary analysis from a prospective observational study included all term singletons undergoing trial of labor after previous cesarean delivery. Body mass index groups were as follows: normal 18.5-24.9, overweight 25.0-29.9, obese 30.0-39.9, morbidly obese 40.0 kg/m2 or greater, and were compared for failure and maternal and neonatal morbidities. The morbidly obese trial of labor and elective repeat cesarean delivery were compared for maternal and neonatal morbidities. Multivariable logistic regression analysis controlled for confounding variables. RESULTS: There were 14,142 trial of labor participants and 14,304 elective repeat cesarean delivery participants. Increasing BMI was directly associated with failed trial of labor after previous cesarean delivery: from 15.2% in normal weight (1,344) to 39.3% in morbidly obese (1,638), with combined risk of rupture/dehiscence increasing from 0.9% to 2.1% in morbidly obese women. Among morbidly obese women, trial of labor carried greater than five-fold risk of uterine rupture/dehiscence (2.1% versus 0.4%), almost a two-fold increase in composite maternal morbidity (7.2% versus 3.8%) and five-fold risk of neonatal injury (1.1% versus 0.2%) (fractures, brachial plexus injuries, and lacerations), but no neonatal encephalopathy. Morbidly obese women failing a trial of labor had six-fold greater composite maternal morbidity than those undergoing a successful trial of labor (14.2% versus 2.6%). CONCLUSION: Body mass index correlates with outcomes in trial of labor after previous cesarean delivery. Morbidly obese women undergoing a trial of labor were at increased risk for failure. Increased BMI was associated with greater composite morbidity and neonatal injury compared with elective repeat cesarean delivery, but absolute morbidities were small. Increased risks should be considered before trial of labor after previous cesarean delivery. LEVEL OF EVIDENCE: II-2.

Adult↗

Decision-to-incision times and maternal and infant outcomes.

OBJECTIVE: To measure decision-to-incision intervals and related maternal and neonatal outcomes in a cohort of women undergoing emergency cesarean deliveries at multiple university-based hospitals comprising the National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. METHODS: All women undergoing a primary cesarean delivery at a Network center during a 2-year time span were prospectively ascertained. Emergency procedures were defined as those performed for umbilical cord prolapse, placental abruption, placenta previa with hemorrhage, nonreassuring fetal heart rate pattern, or uterine rupture. Detailed information regarding maternal and neonatal outcomes, including the interval from the decision time to perform cesarean delivery to the actual skin incision, was collected. RESULTS: Of the 11,481 primary cesarean deliveries, 2,808 were performed for an emergency indication. Of these, 1,814 (65%) began within 30 minutes of the decision to operate. Maternal complication rates, including endometritis, wound infection, and operative injury, were not related to the decision-to-incision interval. Measures of newborn compromise including umbilical artery pH less than 7 and intubation in the delivery room were significantly greater when the cesarean delivery was commenced within 30 minutes, likely attesting to the need for expedited delivery. Of the infants with indications for an emergency cesarean delivery who were delivered more than 30 minutes after the decision to operate, 95% did not experience a measure of newborn compromise. CONCLUSION: Approximately one third of primary cesarean deliveries performed for emergency indications are commenced more than 30 minutes after the decision to operate, and the majority were for nonreassuring heart rate tracings. In these cases, adverse neonatal outcomes were not increased. LEVEL OF EVIDENCE: II-2.

Adolescent↗

Risk of uterine rupture with a trial of labor in women with multiple and single prior cesarean delivery.

OBJECTIVE: To determine whether the risk for uterine rupture is increased in women attempting vaginal birth after multiple cesarean deliveries. METHODS: We conducted a prospective multicenter observational study of women with prior cesarean delivery undergoing trial of labor and elective repeat operation. Maternal and perinatal outcomes were compared among women attempting vaginal birth after multiple cesarean deliveries and those with a single prior cesarean delivery. We also compared outcomes for women with multiple prior cesarean deliveries undergoing trial of labor with those electing repeat cesarean delivery. RESULTS: Uterine rupture occurred in 9 of 975 (0.9%) women with multiple prior cesarean compared with 115 of 16,915 (0.7%) women with a single prior operation (P = .37). Multivariable analysis confirmed that multiple prior cesarean delivery was not associated with an increased risk for uterine rupture. The rates of hysterectomy (0.6% versus 0.2%, P = .023) and transfusion (3.2% versus 1.6%, P < .001) were increased in women with multiple prior cesarean deliveries compared with women with a single prior cesarean delivery attempting trial of labor. Similarly, a composite of maternal morbidity was increased in women with multiple prior cesarean deliveries undergoing trial of labor compared with those having elective repeat cesarean delivery (odds ratio 1.41, 95% confidence interval 1.02-1.93). CONCLUSION: A history of multiple cesarean deliveries is not associated with an increased rate of uterine rupture in women attempting vaginal birth compared with those with a single prior operation. Maternal morbidity is increased with trial of labor after multiple cesarean deliveries, compared with elective repeat cesarean delivery, but the absolute risk for complications is small. Vaginal birth after multiple cesarean deliveries should remain an option for eligible women. LEVEL OF EVIDENCE: II-2.

Adult↗

Blood transfusion and cesarean delivery.

OBJECTIVE: To evaluate risks for intraoperative or postoperative packed red blood cell transfusion in women who underwent cesarean delivery. METHODS: This was a 19-university prospective observational study. All primary cesarean deliveries from January 1, 1999, to December 31, 2000, and all repeat cesareans from January 1, 1999, to December 31, 2002, were included. Trained, certified research nurses performed systematic data abstraction. Primary and repeat cesarean deliveries were analyzed separately. Univariable analyses were used to inform multivariable analyses. RESULTS: A total of 23,486 women underwent primary cesarean delivery, of whom 762 (3.2%) were transfused (median 2 units, 25th% to 75th% 2-3 units). A total of 33,683 women underwent repeat [corrected] cesarean delivery, and 735 (2.2%) were transfused (median 2 units, 25th% to 75th% 2-4 units). Among primary cesareans, general anesthesia (odds ratio [OR] 4.2, 95% confidence interval [CI] 3.5-5.0), placenta previa (OR 4.8, CI 3.5-6.5) and severe (hematocrit less than 25%) preoperative anemia (OR 17.0, CI 12.4-23.3) increased the odds of transfusion. Among repeat cesareans, the risk was increased by general anesthesia (OR 7.2, CI 5.9-8.7), a history of five or more prior cesareans (OR 7.6, CI 4.0-14.3), placenta previa (OR 15.9, CI 12.0-21.0), and severe preoperative anemia (OR 19.9, CI 14.5-27.2). CONCLUSION: Overall, the risk of transfusion in association with cesarean is low. However, both severe preoperative maternal anemia and placenta previa are associated with markedly increased risks. The former argues for optimizing maternal antenatal iron status to avoid severe anemia and the latter for careful perioperative planning when previa complicates cesarean. LEVEL OF EVIDENCE: II-2.

Anemia↗

Fetal injury associated with cesarean delivery.

OBJECTIVE: To describe the incidence and type of fetal injury identified in women undergoing cesarean delivery. METHODS: Between January 1, 1999, and December 31, 2000, a prospective cohort study of all cesarean deliveries was conducted at 13 university centers. Information regarding maternal and infant outcomes was abstracted directly from hospital charts. RESULTS: A total of 37,110 cesarean deliveries were included in the registry, and 418 (1.1%) had an identified fetal injury. The most common injury was skin laceration (n = 272, 0.7%). Other injuries included cephalohematoma (n = 88), clavicular fracture (n = 11), brachial plexus (n = 9), skull fracture (n = 6), and facial nerve palsy (n = 11). Among primary cesarean deliveries, deliveries with a failed forceps or vacuum attempt had the highest rate of injuries (6.9%). In women with a prior cesarean delivery, the highest rate of injury also occurred in the unsuccessful trial of forceps or vacuum (1.7%), and the lowest rate occurred in the elective repeat cesarean group (0.5%). The type of uterine incision was associated with fetal injury, 3.4% "T" or "J" incision, 1.4% for vertical incision, and 1.1% for a low transverse (P = .003), as was a skin incision-to-delivery time of 3 minutes or less. Fetal injury did not vary in frequency with the type of skin incision, preterm delivery, maternal body mass index, or infant birth weight greater than 4,000 g. CONCLUSION: Fetal injuries complicate 1.1% of cesarean deliveries. The frequency of fetal injury at cesarean delivery varies with the indication for surgery as well as with the duration of the skin incision-to-delivery interval and the type of uterine incision. LEVEL OF EVIDENCE: II-3.

Adult↗

Thrombophilia and adverse maternal-perinatal outcome.

A recent review of the literature on thrombophilia and adverse pregnancy outcome (APO) reveals contradictory findings. We have limited our review of literature mostly to the most recent decade. On the basis of our review, screening for thrombophilias with a history of APO (preeclampsia, abruptio placenta, intrauterine growth restriction, and fetal loss) is not clear. There are retrospective and prospective studies that recommend testing for genetic and acquired markers of thrombophilia for those with the enumerated APO. The rationale for such recommendation is to use heparin prophylaxis in subsequent pregnancies. However, this recommendation is not based on randomized trials. Hence, a randomized double-blinded controlled trial is urgently needed to evaluate the benefit of heparin during pregnancy in women with a history of APO in association with thrombophilia.

Abortion, Spontaneous↗