This retrospective analysis confirms the data reported in the literature, with inguinal hernia being more common in males, our ratio being 4.6 males:1 female. Hernias are more common on the right side. Twenty-nine % of the girls presented with palpable gonads at the time of presentation. The reported prevalence of complete androgen insensitivity syndrome is between 2 and 5 per 100,000 live births . About 70–80% of cases of complete androgen insensitivity syndrome present with unilateral or bilateral inguinal hernia in childhood . Complete androgen insensitivity syndrome may present in adolescence with primary amenorrhea during puberty with normal breast development and pubertal growth spurts at the appropriate age.
In our series, we did a FISH test in almost all cases of female hernias with palpable gonads; there was no case in which Y chromosome was detected. This is comparable to previous studies , though in that study all females with inguinal hernia were screened using buccal mucosa smear to look for Y chromosome pattern. In another study, Timo et al.  found one case of CAIS out of the 109 cases screened. In another study , three cases of CAIS were seen out of 270 cases screened. They measured the vaginal length in all females as a screening tool and confirmed the diagnosis using karyotyping. Despite being an inexpensive and innocuous screening test, it has got low sensitivity. Considering the low incidence of disorders of sexual differentiation subjecting every case of female inguinal hernia to chromosomal analysis may not appear to be justifiable as it may increase undue anxiety amongst the parents. On the other hand, failure to exclude complete androgen insensitivity syndrome will result in these children presenting in puberty with primary amenorrhea with its associated anatomical and psychological complications. It could be argued that these psychological effects might have been reduced by the knowledge earlier in their childhood that they would occur. In addition, vaginal reconstruction could have been planned before the onset of sexual activity. Many surgeons screen for CAIS by rectal examination or pelvic ultrasound but neither of these is conclusive to exclude this disorder .
Thus, genetic analysis is the only way in which we can effectively screen this disorder in girls with inguinal hernia. The fluorescent in situ hybridization technique is a quicker and efficient alternative when compared to karyotyping. It takes about 4 days to get the FISH result whereas it takes around 2–3 weeks for complete karyotyping. Thus, all girls with an inguinal hernia with palpable gonads should undergo a FISH analysis prior to elective hernia repair. It is not justifiable to lose an opportunity to diagnose this disorder which has got long-term consequences. Most of the earlier studies screened all the girls that presented with inguinal hernia, we limited our screening to only those girls that presented with palpable gonads.
Limitations of the study
The incidence of CAIS in females with hernias and palpable gonads is 4 in 1,000,000 cases. Hence, we need to screen a large number of cases to eventually test the sensitivity of FISH at detecting CAIS in females with hernias and palpable gonads. More studies in direction are required to establish this. Another limitation of this study is that FISH is an expensive test and has limited availability.