Sex-based differences in inguinal hernia factors.

BACKGROUND: Much of our knowledge about inguinal hernias is based on males. Meanwhile, it is established that women have worse outcomes after inguinal hernia repair, with more chronic pain and higher recurrences. Pediatric literature shows inguinal hernias in females are more likely to be bilateral, incarcerated, and carry a stronger genetic predisposition than males. We aimed to evaluate sex-based differences in inguinal hernia factors in adults, to help supplement the paucity of literature in the adult population.

METHODS: An institutional database of patients undergoing repair of primary inguinal hernias was queried with focus on preoperative risk factors and operative characteristics. Multivariate analysis was performed looking for independent variables associated with a greater number of hernia defects found intraoperatively.

RESULTS: Among 494 patients, 202 (40.9%) were female. Number of risk factors among females was significantly higher than males (1.53 vs 1.2, p = 0.003). Females had significantly more constipation, GERD, and asthma and lower BMI than males. Family history of hernias was similar between both sexes. As expected, females had significantly less direct hernias (12.9% vs 32.9%, p < 0.001) and more femoral hernias (38.5% vs 12.2%, p < 0.001) than males. Bilaterality was similar. Females undergoing inguinal hernia repair averaged 1.23 prior deliveries. Regression analysis showed age, sex, BMI, and number of deliveries were not correlated with the number of defects.

CONCLUSIONS: Females undergoing primary inguinal hernia repair had more preoperative risk factors for inguinal hernia than males. In our population, there was no higher incidence of bilaterality or significant genetic predisposition in females as noted by family history of hernias. Age, sex, BMI and number of deliveries did not correlate with the number of hernia defects found. Our study promotes awareness of inguinal hernias in females and presents new data to quantify sex-based differences and predispositions to inguinal hernias.