From the Guidelines
Indirect inguinal hernias occur significantly more frequently in males than females, with males being approximately 9 times more likely to develop this condition. In men, the lifetime risk is about 27%, compared to only 3% in women 1. This striking gender disparity is primarily due to anatomical differences in development. During male fetal development, the processus vaginalis (an outpouching of peritoneum) follows the testicle as it descends through the inguinal canal into the scrotum. If this processus vaginalis fails to close completely after testicular descent, it creates a potential pathway for abdominal contents to herniate, resulting in an indirect inguinal hernia. In females, the round ligament follows a similar path but without the same degree of anatomical vulnerability. Additionally, the male inguinal canal tends to be larger to accommodate the spermatic cord, creating a natural weakness.
Some key points to consider include:
- The processus vaginalis plays a critical role in the development of indirect inguinal hernias 1
- Anatomical differences between males and females, such as the size of the inguinal canal and the presence of the spermatic cord, contribute to the higher incidence of indirect inguinal hernias in males
- The lifetime risk of developing an indirect inguinal hernia is significantly higher in men than in women, with a lifetime risk of about 27% in men and 3% in women 1
- Indirect inguinal hernias are more common in young men, while women who develop inguinal hernias are more likely to have direct hernias related to weakening of the abdominal wall rather than the congenital predisposition seen in males.
It's worth noting that while the provided evidence includes studies from 2012, the principles of anatomy and development that contribute to the formation of indirect inguinal hernias remain consistent, and the recommendation to recognize the higher incidence of indirect inguinal hernias in males remains a crucial aspect of diagnosis and treatment 1.
From the Research
Rates of Indirect Inguinal Hernia
- The occurrence of indirect inguinal hernias is 5 times more prevalent than that of direct inguinal hernias and it is 7 times more common in males 2.
- In children, the immense mainstream of inguinal hernias is indirect, and the progress of indirect inguinal hernia development in children is instigated with a patent processus vaginalis (PV) 2.
- The lifetime risk to develop an inguinal hernia is 27-43% for men and 3-6% for women, indicating a significant difference in the rates of inguinal hernias between males and females 3.
Sex-Based Differences
- Females have worse outcomes after inguinal hernia repair, with more chronic pain and higher recurrences compared to males 4.
- Pediatric literature shows inguinal hernias in females are more likely to be bilateral, incarcerated, and carry a stronger genetic predisposition than males 4.
- However, in adults, there was no higher incidence of bilaterality or significant genetic predisposition in females as noted by family history of hernias 4.
Diagnosis and Management
- Inguinal hernias are more common in men, and although groin hernias are easily diagnosed on physical examination in men, ultrasonography is often needed in women 5.
- Laparoscopic repair is associated with shorter recovery time, earlier resumption of activities of daily living, less pain, and lower recurrence rates than open repair 5.
- Watchful waiting is a reasonable and safe option in men with asymptomatic or minimally symptomatic inguinal hernias, but not recommended in patients with symptomatic hernias or in nonpregnant women 5.