Factors predictive of failed operative vaginal delivery

Abstract

To determine which maternal, fetal, pregnancy, or provider-related characteristics are associated with an increased likelihood of failed operative vaginal delivery (FOVD). We performed a case-control study using the Washington (WA) State Birth Certificate Database. All live-born, singleton births in WA State from 1992-2001 with both cesarean section and an OVD (forceps and/or vacuum) coded as the delivery method were selected as cases (n = 1750). Live-born, singleton births with only forceps and/or vacuum coded as the delivery method were randomly selected as controls, with frequency matched to cases by year of birth in a 2:1 ratio (n = 3500). We measured the degree of association between FOVD and predictive factors of interest with adjusted odds ratios (ORs), estimated using the Mantel-Haenszel technique. All reported ORs were statistically significant (P<.05). Compared with women of normal weight, overweight (OR 1.6) and obese (OR 1.7) women were more likely to have an FOVD. Women aged 30-39 (OR 1.5) and those ≥40 years (OR 2.7) were more likely to have an FOVD than women younger than 30. Gestational diabetes (OR 1.5), preexisting diabetes (OR 2.8), birthweight ≥4000 g (OR 2.1), and identification as African American (OR 2.5) independently increased the likelihood of FOVD. Maternal weight, age, diabetes, and race, as well as fetal birthweight, were found to be independently associated with FOVD. Identification of factors associated with FOVD will enable providers to better counsel patients as to the likelihood of FOVD and allow improved planning and allocation of surgical resources.