Relationships between female infertility and female genital infections and pelvic inflammatory disease: a population-based nested controlled study.

Our purpose was to examine the associations of female genital infections and certain comorbidities with infertility.

The Taiwan National Health Research Database was searched for women with a new diagnosis of infertility between 2000 and 2013. Women without a diagnosis of infertility served as a control group and were matched with the infertility cases by age (±3 years) and index year. They were divided into two groups: ≤40 years old and >40 years old. Univariate and multivariate conditional logistic regression models were employed to identify the risk factors associated with infertility.

A total of 18,276 women with a new diagnosis of infertility and 73,104 matched controls (mean cohort age, 31±6.2 years) were included. According to the adjusted multivariate analysis, pelvic inflammatory disease involving the ovary, fallopian tube, pelvic cellular tissue, peritoneum (odds ratio (OR)=4.823), and uterus (OR=3.050) and cervical, vaginal, and vulvar inflammation (OR=7.788) were associated with an increased risk of infertility in women aged ≤40 years. In women aged >40 years, pelvic inflammatory disease of the ovary, fallopian tube, pelvic cellular tissue, and peritoneum (OR=6.028) and cervical, vaginal, and vulvar inflammation (OR=6.648) were associated with infertility. Obesity, lipid metabolism disorders, dysthyroidism, abortion (spontaneous or induced), bacterial vaginosis, endometritis, and tubo-ovarian abscess were associated with an increased risk of infertility according to the univariate analysis but not the multivariate analysis.

Female genital tract infections, but not the comorbidities studied here, are associated with an increased risk of infertility.