Abnormal placentation: evidence-based diagnosis and management of placenta previa, placenta accreta, and vasa previa.

Placenta previa, placenta accreta, and vasa previa cause significant maternal and perinatal morbidity and mortality. With the increasing incidence of both cesarean delivery and pregnancies using assisted reproductive technology, these 3 conditions are becoming more common. Advances in grayscale and Doppler ultrasound have facilitated prenatal diagnosis of abnormal placentation to allow the development of multidisciplinary management plans to achieve the best outcomes for mother and baby.

The impact of prior preeclampsia on the risk of superimposed preeclampsia and other adverse pregnancy outcomes in patients with chronic hypertension.

Objective: We sought to compare the rates of superimposed preeclampsia and adverse outcomes in women with chronic hypertension with or without prior preeclampsia.

Study Design: We conducted secondary analysis of 369 women with chronic hypertension (104 with prior preeclampsia) enrolled at 12-19 weeks as part of a multisite trial of antioxidants to prevent preeclampsia (no reduction was found). Outcome measures were rates of superimposed preeclampsia and other adverse perinatal outcomes.

Antioxidant supplementation and premature rupture of the membranes: a planned secondary analysis.

Objective: The purpose of this study was to determine if antioxidant supplementation during pregnancy reduces the incidence of premature rupture of the membranes (PROM).

Study Design: A placebo-controlled, double-blind trial was conducted. PROM and preterm PROM (PPROM) were planned secondary outcomes of the trial.

Serum inhibin A and angiogenic factor levels in pregnancies with previous preeclampsia and/or chronic hypertension: are they useful markers for prediction of subsequent preeclampsia?

Objective: Our objective was to determine whether measurement of placenta growth factor (PLGF), inhibin A, or soluble fms-like tyrosine kinase-1 (sFlt-1) at 2 times during pregnancy would usefully predict subsequent preeclampsia (PE) in women at high risk.

Study Design: We analyzed serum obtained at enrollment (12(0/7) to 19(6/7) weeks) and follow-up (24-28 weeks) from 704 patients with previous PE and/or chronic hypertension (CHTN) enrolled in a randomized trial for the prevention of PE. Logistic regression analysis assessed the association of log-transformed markers with subsequent PE; receiver operating characteristic analysis assessed predictive value.

Antioxidant therapy to prevent preeclampsia: a randomized controlled trial.

Objective: To study whether antioxidant supplementation will reduce the incidence of preeclampsia among patients at increased risk.

Methods: A randomized, placebo-controlled, double-blind clinical trial was conducted at four Brazilian sites. Women between 12 0/7 weeks and 19 6/7 weeks of gestation and diagnosed to have chronic hypertension or a prior history of preeclampsia were randomly assigned to daily treatment with both vitamin C (1,000 mg) and vitamin E (400 International Units) or placebo.

Metabolism, tissue distribution, and pharmacokinetics of N-methyl-N-2,4,6-tetranitroaniline (tetryl).

Tetryl (N-methyl-N,2,4,6-tetranitroaniline) is a booster explosive that was used in the production of detonators and blasting caps. It is an environmental contaminant that is found in detectable levels in areas associated with its production, use, storage, and disposal. Preliminary microsomal assays showed that one major metabolite was formed under anaerobic and aerobic conditions with both NADH and NADPH as cofactors.

Tissue distribution and elimination of N-methyl-N-2,4,6-tetranitroaniline (tetryl) in rats.

The elimination of tetryl was studied using ring-labeled 14C-tetryl. Tetryl was given subcutaneously to male Sprague-Dawley rats at doses of 25, 100, and 300 mg kg(-1), and urine and feces were collected 24 h post-injection. Percent urinary elimination was observed to be 10.

New therapies in the prevention of preeclampsia.

Purpose Of Review: The review summarizes the results of recent randomized clinical trials whose primary purpose was to prevent preeclampsia and explores safety concerns that have been raised by these trials. Preeclampsia remains one the most common causes of perinatal and maternal mortality, particularly in resource-poor developing countries where its impact on morbidity and mortality is 20 to 100-fold greater than that in developed countries. The potential benefit of antioxidant vitamins and calcium continue to be explored, and are the subject of this review.

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.

Prevention and management of RhD isoimmunization.

An Rh-negative woman is at risk for developing Rh isoimmunization upon exposure to RhD antigens from her Rh-positive baby through fetal-maternal hemorrhage. The incidence of Rh isoimmunization and fetal hemolytic disease has decreased substantially since Rh immune globulin was introduced in 1968. When RhD sensitization does occur, careful follow-up of these mothers and judicious intervention can result in good outcomes for most pregnancies.

The pattern of change in the lecithin/sphingomyelin ratio in patients with preterm premature rupture of membranes between 24 and 34 weeks' gestation.

Objective: To report the pattern of change in the lecithin/sphingomyelin (L/S) ratio in patients with preterm premature rupture of membranes (PPROM) between 24 and 34 weeks' gestation.

Study Design: L/S was determined prospectively using transvaginally and transabdominally collected amniotic fluid from patients with PPROM between 24 and 34 weeks' gestation. Samples were collected prospectively on admission and every 48 to 96 hours until L/S was > or =2.