BACKGROUND: According to the World Health Organization (WHO), 10-15% of couples of reproductive age have infertility. According to researcher D. Sukhe (1999), hormonal infertility in the reproductive age of women was 33.6%, which was a large part of the cause of infertility. In recent years, the number of cases of endocrine disorders, including malignancy and sexually transmitted infections, has been increasing year by year. According to WHO reports, thyroid disorders have a prevalence of 49.3% for active reproductive age (30-50). According to the report of the Health Development Center in 2016, since the thyroid disorders are the second most common disease in endocrine gland disease, our study found that the infertility in reproductive age of women can be substantial due to the loss of thyroid gland. METHODS: The study was carried out by the couple of 20-45 year-olds and modeled as an analytical study model. The questionnaire was used for the couple’s interviews and some of the measurement of body and serum use of TOSOH Corporation AIA-360, Tokyo, Japan. On the serum, anti-TPO and аnti-TG carbohydrates are identified by the Cobas e-411 analyzer under the manufacturer’s accompanying protocol. RESULTS: 76.7% of women were diagnosed with infertility euthyroid, 0.7% hyperthyroidism, 22.6% hypothyroidism (3.8% with overt hypothyroidism and 18.8% subclinical hypothyroidism). Prevalence of TAI, in 6.7% isolated positive anti-Tg were found, and 14.3% had isolated positive TPO, In 3.7% of cases, both types of autoantibodies were present. We analysed binary logistic regression for anti-TPO and anti-TG autoantibody in the positive and negative group in past obstetrics history, evidence of positive of anti-TPO and anti-Tg was increased risk of miscarriage 2.2 times (OR = 2.2, p <0.01). CONCLUSIONS: Women with disorders in our study have high percentage of subclinical hypothyroidism and have higher rate of thyroid autobodies in serum which may be a problem for women with infertility and pregnancy complications due to the loss of thyroid gland. There is a need to develop a principle of recovery and treatment.

Purpose: Researchers suggest that the prevalence of infertility varies between developing and developed countries, with differences in infertility care, socioeconomic status, lifestyle, and reproductive disorders such as pelvic inflammatory disease and sexually transmitted infections being the main risk factors. The research project aims is to define risk factors for female fertility in the Mongolian population. Methods: This study was conducted between 2016-2018 using a cross-sectional survey of analytical research. Participants were randomly selected from Ulaanbaatar and the Central, Western, Eastern, and Khangai provinces according to Mongolia’s regional geographic model. The contents of a questionnaire were comprised of 5 units with 95 questions including socio-economic, geographical, lifestyle, health education, reproductive health indicators, sexual behavior. General physical characteristics were measured according to the standard. Results: The prevalence of the female fertility rate in the Mongolian population is 7.4%. Female participants were classified into 2 groups, namely infertile and fertile, and we developed a case-control study. Among the socio-economic factors influencing infertility, primary education aOR: 1.6 (95% CI 0.98-2.66), monthly household income lower than the average aOR: 1.1 (95% CI 0.77- 1.66), living in rural areas OR: 2.3 ( 95% CI 1.46-3.68) were crucial risk factors. As for reproductive and general health indicators, STIs aOR: 1.8 (95% CI 0.98-3.50), especially gonorrhea OR: 2.8 (95% CI 1.14-6.91), and thyroid disorders OR: 1.7 (95% CI 1.03). -2.97), grade 3 obesity OR: 3.8 (95% CI 1.05-13.95) are estimated risk factors for infertility. Conclusions Of all potential socio-economic factors, residence status, education and financial situation are significant for female infertility meanwhile reproductive health indicators include sexually transmitted infections, thyroid disease, and obesity.