Vacuum-assisted delivery outcomes: is advanced maternal age a factor?

Abstract

This study evaluated age-related maternal outcomes of vacuum-assisted vaginal deliveries (VAD). This retrospective cohort study included all nulliparous women with singleton VAD in one academic institution. Study group parturients were maternal age ≥ 35years and controls < 35. Power analysis revealed that 225 women/group would be sufficient to detect a difference in the rate of third- and fourth-degree perineal tears (primary maternal outcome) and umbilical cord pH < 7.15 (primary neonatal outcome). Secondary outcomes were maternal blood loss, Apgar scores, cup detachment, and subgaleal hematoma. Outcomes were compared between groups. From 2014 to 2019, 13,967 nulliparas delivered at our institution. Overall, 8810 (63.1%) underwent normal vaginal delivery, 2432 (17.4%) instrumental, and 2725 (19.5%) cesarean. Among 11,242 vaginal deliveries, 10,116 (90%) involved women < 35, including 2067 (20.5%) successful VAD vs. 1126 (10%) women ≥ 35years with 348 (30.9%) successful VAD (p < 0.001). Rates of third- and fourth-degree perineal lacerations were 6 (1.7%) with advanced maternal age and 57 (2.8%) among controls (p = 0.259). Cord pH < 7.15 was similar: 23 (6.6%) study group and 156 (7.5%) controls (p = 0.739). Advanced maternal age and VAD are not associated with higher risk for adverse outcomes. Older, nulliparous women are more likely to undergo vacuum delivery than younger parturients.