Epidemiological characteristics in women with and without endometriosis in the Yale series

The association between demographic factors, menstrual and reproductive characteristics, and clinical profile for women with endometriosis was analyzed in a retrospective case-control study.

Over a 6-year period, 535 women with endometriosis and 200 infertile women without endometriosis, studied by laparoscopy or laparotomy, were evaluated. Information was then collected in a uniform manner from the patients’ medical records. Statistical methods included χ ² and Mann–Whitney U test.

The factors associated with an increased risk for endometriosis include lower body weight, alcohol use (χ ² = 8.8; P < 0.003), early menarche (χ ² = 5.08; P < 0.024), shorter cycle length (χ ² = 13.06; P < 0.001), and heavier menstrual cycles. Pelvic pain was present in 79.1% of women with endometriosis, dysmenorrhea in 70.2%, and dyspareunia in 49.5%. These symptoms were statistically significantly higher in comparison with the infertile women without endometriosis (P < 0.001). Moreover, we found that women with endometriosis had fewer prior pregnancies, elective abortions and ectopic pregnancies compared to women seeking care for infertility, who did not have endometriosis. Interestingly, women with endometriosis were significantly more likely to report a family history of cancer compared to women in control group (χ ² = 78.2; P < 0.001).

Body habitus, personal habits and menstrual characteristics are all strongly associated with the development of endometriosis. There may also be an association between family history of cancer and the development of endometriosis.