Abstract
Introduction: The association between pregnancy and risk for ventral hernia recurrence is not clear. This study aims to assess (1) the incidence of ventral hernia in women, and (2) whether increasing parity is associated with a greater risk for developing ventral hernia. Method: This nationwide cohort study included women born 1950–1980 who were registered in the Swedish Birth Register (MBR). Data on pregnancies and vaginal or caesarian section were retrieved from the Birth Register. The cohort was cross-matched with the National Patient Register (NPR) to identify subsequent primary hernia repairs. Result: A total of 1,630,754 women born between 1950 and 1980 were included in the study. Among them, 1,588,609 (92.3%) were registered for at least one birth. The incidence rate for Umbilical Hernia Repair (UHR) and Epigastric Hernia Repair (EHR) was 13.21 per 100,000 person-years and 5.4 per 100,000 person-years, respectively. When compared with women registered for one delivery, the incidence rate ratio for UHR was higher among those with two deliveries registered (1.3, 95% CI: 1.26–1.33) and among those registered with ≥ 3 deliveries (1.6, 95% CI: 1.58–1.68). The incidence rate ratios were (1.29, 95% CI: 1.20–1.39) and 1.34 (1.34, 95% CI: 1.24–1.45) for EHR among women with two and ≥ 3 registered deliveries, respectively. Conclusion: A history of more than one pregnancy is associated with increased incidences of umbilical and epigastric hernias.