(851) Trial of labor after failed vacuum assisted delivery – maternal and neonatal outcomes

Failed vacuum-assisted vaginal delivery is a sub-group of second-stage cesarean delivery and is a well-established proxy for maternal complications. We aimed to study the maternal and neonatal outcomes among women in a trial of labor following a second stage cesarean delivery with and without a history of failed vacuum-assisted delivery.

Study Design:

A multicenter retrospective cohort study of women who underwent a trial of labor after cesarean at the second stage of delivery between 2005 and 2021. Parturients with singleton live fetuses who had two subsequent deliveries in our medical centers were included. Univariate analyses were followed by multivariate analysis (adjusted Odds Ratio (aORs); [95% Confidence Interval]).

Results:

During the study period, 906 women with previous pregnancy second stage cesarean underwent a trial of labor and met inclusion and exclusion criteria, of whom 162 (17.9%) had a history of failed vacuum and 744 (82.1%) didn't. Among women with previous second stage cesarean, the successful trial of labor after cesarean rates among women with and without failed VAD in index delivery (22.8% s. 22.2%, p=0.86) was comparable. History of failed vacuum wasn't found to be significantly associated with preterm delivery or other maternal adverse outcomes except for significantly higher rates of recurrent failed vacuum among women with a history of previously failed vacuum (Table 1). As regards the neonatal outcome, SGA rates were found to be significantly lower in the failed vacuum group. Multivariate analyses showed that a history of failed vacuum is associated with neither preterm delivery nor composite adverse maternal outcome (Table 2).

Conclusion:

Among women with a previous second-stage cesarean, a history of failed vacuum may not serve as a proxy for worse maternal or neonatal outcomes amongst women undergoing a trial of labor.