Lower uterine segment thickness to prevent uterine rupture and adverse perinatal outcomes: a multicenter prospective study.

Background: Choice of delivery route after previous cesarean delivery can be difficult because both trial of labor after cesarean delivery and elective repeat cesarean delivery are associated with risks. The major risk that is associated with trial of labor after cesarean delivery is uterine rupture that requires emergency laparotomy.

Objective: This study aimed to estimate the occurrence of uterine rupture during trial of labor after cesarean delivery when lower uterine segment thickness measurement is included in the decision-making process about the route of delivery.

Maternal exposure to drinking-water chlorination by-products and small-for-gestational-age neonates.

Background: There is concern about possible effects of disinfection by-products on reproductive outcomes. The purpose of this study was to evaluate the association between maternal exposure to chlorination by-products and the risk of delivering a small for-gestational-age (SGA) neonate.

Methods: We conducted a population-based case-control study in the Québec City (Canada) area.

Prevention of preeclampsia and intrauterine growth restriction with aspirin started in early pregnancy: a meta-analysis.

Objective: To estimate the effect of low-dose aspirin started in early pregnancy on the incidence of preeclampsia and intrauterine growth restriction (IUGR).

Data Sources: A systematic review and meta-analysis were performed through electronic database searches (PubMed, Cochrane, Embase).

Methods Of Study Selection: Randomized controlled trials of pregnant women at risk of preeclampsia who were assigned to receive aspirin or placebo (or no treatment) were reviewed.

The role of uterine closure in the risk of uterine rupture.

Objective: To evaluate the effects of prior single-layer compared with double-layer closure on the risk of uterine rupture.

Methods: A multicenter, case-control study was performed on women with a single, prior, low-transverse cesarean who experienced complete uterine rupture during a trial of labor. For each case, three women who underwent a trial of labor without uterine rupture after a prior low-transverse cesarean delivery were selected as control participants.

Population-based study on occupational risk factors for preeclampsia and gestational hypertension.

Objectives: Preeclampsia is a leading cause of maternal and perinatal morbidity. Work-related factors may influence the occurrence of this disorder. This case-control study estimated the associations between work-related physical and psychosocial factors and the risk of preeclampsia and gestational hypertension.

Work activity in pregnancy, preventive measures, and the risk of preterm delivery.

The objective of this case-control study was to evaluate whether occupational conditions during pregnancy are associated with preterm delivery (PTD). Women whose work conditions changed following the use of a legally justified preventive measure (withdrawal from work or job reassignment) were also compared with those whose work conditions did not change. Cases (n = 1,242) and controls (n = 4,513) were selected from 43,898 women who had single livebirths between January 1997 and March 1999 in Québec, Canada.

Work activity in pregnancy, preventive measures, and the risk of delivering a small-for-gestational-age infant.

Objectives: We undertook a case-control study to evaluate whether some occupational conditions during pregnancy increase the risk of delivering a small-for-gestational-age (SGA) infant and whether taking measures to eliminate these conditions decreases that risk.

Methods: The 1536 cases and 4441 controls were selected from 43898 women who had single live births between January 1997 and March 1999 in Québec, Canada. The women were interviewed by telephone after delivery.

Amnioinfusion for the prevention of the meconium aspiration syndrome.

Background: It is uncertain whether amnioinfusion (infusion of saline into the amniotic cavity) in women who have thick meconium staining of the amniotic fluid reduces the risk of perinatal death, moderate or severe meconium aspiration syndrome, or both.

Methods: We performed a multicenter trial in which 1998 pregnant women in labor at 36 or more weeks of gestation who had thick meconium staining of the amniotic fluid were stratified according to the presence or absence of variable decelerations in fetal heart rate and then randomly assigned to amnioinfusion or to standard care. The composite primary outcome measure was perinatal death, moderate or severe meconium aspiration syndrome, or both.

Customized birth weight for gestational age standards: Perinatal mortality patterns are consistent with separate standards for males and females but not for blacks and whites.

BACKGROUND: Some currently available birth weight for gestational age standards are customized but others are not. We carried out a study to provide empirical justification for customizing such standards by sex and for whites and blacks in the United States. METHODS: We studied all male and female singleton live births and stillbirths (22 or more weeks of gestation; 500 g birth weight or over) in the United States in 1997 and 1998.

Cricoid pressure does not increase the rate of failed intubation by direct laryngoscopy in adults.

Background: Cricoid pressure (CP) is applied during induction of anesthesia to prevent regurgitation of gastric content and pulmonary aspiration. However, it has been suggested that CP makes tracheal intubation more difficult. This double-blind randomized study evaluated the effect of CP on orotracheal intubation by direct laryngoscopy in adults.

Effects of carrying a pregnancy and of method of delivery on urinary incontinence: a prospective cohort study.

BACKGROUND: This study was carried out to identify risk factors associated with urinary incontinence in women three months after giving birth. METHODS: Urinary incontinence before and during pregnancy was assessed at study enrolment early in the third trimester. Incontinence was re-assessed three months postpartum.

Length of hospital stay, obstetric conditions at childbirth, and maternal readmission: a population-based cohort study.

Objective: We assessed the association between obstetric conditions, length of hospital stay for childbirth, and maternal readmission.

Study Design: A population-based cohort study was conducted on obstetric deliveries (N = 2,652,726) in Canada from 1989 to 1999. Women who were readmitted to the hospital because of obstetric causes within 60 days of initial discharge were identified.

Preterm birth, stillbirth and infant mortality among triplet births in Canada, 1985-96.

Recent increases in the frequency of multiple births and simultaneous increases in preterm birth among multiple births have focused attention on such births. However, most previous studies have examined twins rather than higher-order multiples. We carried out a study to examine rates and trends in preterm birth and in gestational age-specific fetal and infant mortality among triplet births in Canada.

Anal incontinence after childbirth.

Background: Incontinence of stool and flatus are frequent complications of childbirth. We examined the prevalence and possible causes of these adverse outcomes in a large cohort of women.

Methods: We studied 949 pregnant women who gave birth in 5 hospitals in 1995/96 in the province of Quebec.

Risk factors for difficult delivery in nulliparas with epidural analgesia in second stage of labor.

Objective: To identify risk factors for difficult delivery among nulliparas in the second stage of labor with continuous epidural analgesia, and to develop a multivariable model that is predictive of difficult delivery.

Methods: The database is derived from a multicenter randomized trial of delayed pushing for nulliparous women under continuous infusion epidural. Members of this cohort (n = 1862) were randomly divided into two groups: a "Model Development" and a "Model Validation" group.