Introduction. Primary hypothyroidism is observed in women of reproductive age in 2–3 % of cases. The most common thyroid pathology during pregnancy is subclinical hypothyroidism (SHT), which is caused by newly diagnosed autoimmune thyroiditis (AIT) or severe iodine deficiency. In some regions of the Russian Federation, the population has a mild iodine deficiency, the average concentration of iodine in the urine being found at 78 µg/L (the normal range is 100–200 µg/L). In women with primary hypothyroidism, complications of pregnancy and childbirth include: premature birth, weakness of labor, eclampsia, premature rupture of premature rupture of membranes (PROM), gestational diabetes mellitus (GDM), intrauterine growth retardation syndrome, fetal macrosomia, congenital hypothyroidism in the fetus, etc.Aim: to study the features of pregnancy and childbirth course in women with primary hypothyroidism.Materials and Methods. In a retrospective study, there were analyzed 62 birth histories, of which 37 were for patients with thyroid diseases. Two groups were formed: the main group – 25 patients with primary hypothyroidism, the comparison group – 25 patients without thyroid pathology. During the study, the next parameters were analyzed: age, number of pregnancies, number of births, term of delivery, body mass index, level of thyroid stimulating hormone (TSH), titer of thyroid peroxidase antibodies, newborn body weight, newborn assessment according to Apgar scale.Results. In the main group, the cause of primary hypothyroidism was as follows: newly diagnosed SHT – in 18 (48.6 %), AIT – in 7 (18.9 %) pregnant women. In the first trimester of pregnancy, TSH level in patients with hypothyroidism was 3.06 ± 0.36 mU/L. The following complications of pregnancy and childbirth course were identified: GDM (32.0 %), anemia of the first degree (12.0 %), large fetus (12.0 %), PROM (12.0 %), perineal rupture of the first degree (16.0 %), anomalies of labor activity with ineffective labor stimulation (8.0 %), pelvic-head disproportion (8.0 %).Conclusion. Timely diagnosis and compensation of hypothyroidism with hormone replacement therapy and iodine preparations, prediction of possible complications and correction of identified complications are the main ways to achieve a successful outcome of pregnancy and childbirth for mother and fetus.