Outcomes of operative vaginal delivery managed by residents under supervision and attending obstetricians: a prospective cross-sectional study.

BACKGROUND: To assess both severe maternal and neonatal mortality and morbidity after attempted operative vaginal deliveries by residents under supervision and by attending obstetricians.

STUDY DESIGN: Secondary analysis of a 5-year prospective study with cross-sectional analysis including 2192 women with live singleton term fetuses in vertex presentation who underwent an attempted operative vaginal delivery in a tertiary care university hospital. Obstetricians who attempted or performed an operative vaginal delivery were classified into 2 groups according to their level of experience: attending obstetricians (who had 5 years or more of experience) and obstetric residents (who had less than 5 years of experience) under the supervision of an attending obstetrician. We used multivariate logistic regression and propensity score methods to compare outcomes associated with attending obstetricians and obstetric residents. Severe maternal morbidity was defined as third- or fourth-degree perineal laceration, perineal hematoma, cervical laceration, extended uterine incision for cesareans, postpartum hemorrhage >1500 mL, surgical hemostatic procedures, uterine artery embolization, blood transfusion, infection, thromboembolic events, admission to the intensive care unit, or maternal death; severe neonatal morbidity was defined as a 5-minute Apgar score <7, umbilical artery pH <7.00, need for resuscitation or intubation, neonatal trauma, intraventricular hemorrhage greater than grade 2, neonatal intensive care unit admission for more than 24 hours, convulsions, sepsis, or neonatal death.

RESULTS: High prepregnancy body mass index, high dose of oxytocin, manual rotation, persistent occiput posterior or transverse positions, operating room delivery, midpelvic delivery, forceps, and spatulas were significantly more frequent in deliveries managed by attending obstetricians than residents whereas a second-stage pushing phase longer than 30 minutes was significantly more frequent in deliveries managed by residents. The rate of severe maternal morbidity was 7.8% (115/1475) for residents vs 9.9% (48/484) for attending obstetricians; for severe neonatal morbidity, the rates were 8.3% (123/1475) vs 15.1% (73/484), respectively. In the univariate, multivariable, and sensitivity analyses, attempted operative vaginal delivery managed by a resident was significantly and inversely associated with severe neonatal but not maternal morbidity. After propensity score matching, delivery managed by a resident was not significantly associated with severe maternal morbidity (adjusted odds ratio, 0.74; 95% confidence interval, 0.39-1.38) and was no longer associated with neonatal morbidity (adjusted odds ratio, 0.51; 95% confidence interval, 0.25-1.04).

CONCLUSION: Management of attempted operative vaginal deliveries by residents under the supervision of attending obstetricians, compared with by the attending obstetricians themselves, does not appear to be associated with either maternal or neonatal morbidity. These reassuring results support the continued use of residency programs for training in operative vaginal deliveries under the supervision of attending obstetricians.