Title: 914: Delivery options for second stage dystopia: a comparison of operative vaginal and cesarean delivery in terms of severe perinatal and maternal morbidity and mortality
Abstract: To quantify severe perinatal and maternal morbidity/mortality associated with operative vaginal delivery by pelvic station compared with cesarean delivery in the second stage of labor. We carried out a population-based, retrospective cohort study among deliveries in Canada from 2003-2013 with data obtained from the Canadian Institute for Health Information. The study included all full term operative vaginal and cesarean deliveries with a prolonged second stage of labor. The primary outcomes were composite severe perinatal morbidity/mortality (i.e., convulsions, assisted ventilation, severe birth trauma, stillbirth and neonatal death) and composite severe maternal morbidity/mortality (i.e., severe postpartum hemorrhage, shock, sepsis, cardiac complications, acute renal failure, obstetric embolism, evacuation of incisional hematoma and death). Logistic regression was used to adjust for maternal age, parity, birth weight, province, and year. The study population included 58,819 deliveries; 36,700 with dystocia and 22,119 with fetal distress. Among women with dystocia, forceps and vacuum deliveries were associated with higher rates of perinatal morbidity/mortality compared with cesarean delivery (all forceps AOR 1.56, 95% CI 1.13-2.17; all vacuum AOR 1.44, 95% CI 1.06-1.97; Figure 1). Maternal morbidity/mortality rates were lower following vacuum delivery compared with cesarean delivery for dystocia (all vacuum AOR 0.64, 95% CI 0.51-0.81) and fetal distress (all vacuum AOR 0.43, 95% CI 0.32-0.57; Figure 1). For both indications, the odds ratios for perinatal and maternal morbidity/mortality were not significantly different among midpelvic vs low vs outlet deliveries by forceps or vacuum. Rates of 3rd and 4th degree perineal lacerations were high (e.g., 11%-23%) among operative vaginal deliveries at all pelvic stations (Figure 2). Among women with a prolonged second stage, operative vaginal delivery is associated with significantly higher rates of perinatal morbidity/mortality compared with cesarean delivery. Although maternal morbidity/mortality rates are lower following vacuum delivery, rates of severe perineal lacerations are high following operative vaginal delivery, irrespective of pelvic station.View Large Image Figure ViewerDownload Hi-res image Download (PPT)