Risk factors for failed vacuum extraction and associated complications in term newborn infants: a population-based cohort study

Objective: The aims of the present study were to investigate risk factors for failed vacuum extraction (VE), and to compare neonatal complications among infants delivered by failed VE with those delivered by successful VE. Methods: Population-based study including all women (and their newborn infants) with singleton pregnancy who gave birth at term by failed VE (n = 4747) or successful VE (n = 83 671) in Sweden between 1999 and 2010. Failed VE was defined as VE followed by an emergency cesarean section (ECS), forceps, or both forceps and ECS. We used logistic regression to examine the association between failed VE in relation to intracranial hemorrhage, subgaleal hemorrhage, Apgar scores <7 at 5 min, and neonatal convulsions. Results: Risk factors for failed VE included occipito posterior position, mid-pelvic fetal station, high birth weight, short maternal stature, epidural analgesia, and induction of labor. Compared with infants born after a successful VE, those delivered by failed VE had a higher risk of subgaleal hemorrhage OR 7.3 CI (5.5-9.7), convulsions OR 1.9 CI (1.4-2.7), and low Apgar OR 2.6 CI (2.3-3.0), but not of ICH. Conclusion: Failed VE is associated with neonatal complications. Fetal head position and station should be carefully assessed prior to the extraction.