ABSTRACT
The article presents the results of determining the frequency of thyroid dysfunction among pregnant women in the third trimester, the relationship of factors with it, and analysis of the effect of thyroid dysfunction on pregnancy outcomes. The study involved 77 women with singleton pregnancies in the third trimester; the average age was 28.7±2.11 years. In all patients, thyroidstimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4) were determined in the blood. Statistical analysis was performed using Microsoft Excel Statistica. In 39.0% of cases, thyroid dysfunction was revealed: subclinical hypothyroidism was detected in 26% of women, overt hypothyroidism in 7.8%, subclinical hyperthyroidism - in 5.2%. In subclinical hypothyroidism, the TSH level was 74.6% (p=0.001), in pregnant women with overt hypothyroidism - by 81.3% (p=0.001) higher than in pregnant women with euthyroidism. In pregnant women with subclinical hypothyroidism, overt hypothyroidism and subclinical hyperthyroidism, the T3 level was reduced by 38.2% (p=0.355), by 78.6% (p=0.004) and by 11.1% (p=0.741), respectively. The T4 value in the blood in women with subclinical hypothyroidism and subclinical hyperthyroidism in comparison with the group with normal functioning of the thyroid gland was increased by 34.6% (p=0.261) and by 39.0% (p=0.004), and in pregnant women with obvious hypothyroidism decreased by 75.6% (p=0.003). In the group of women with subclinical hypothyroidism, 35.0% suffered from anemia, 20.0% of women had preeclampsia, oligohydramnios - in 30.0%, caesarean section - in 35.0% of women. The risk of preeclampsia, anemia, oligohydramnios, caesarean section and premature birth in women with subclinical hypothyroidism, respectively, 5.6 times (p<0.01), 7.9 times (p<0.01), 4.6 times (p<0.05), 3.7 times (p<0.05) and 1.7 times (p>0.05) higher than in those examined with euthyroidism. A statistically significant relationship was established between anemia, preeclampsia, caesarean section, the presence of children with low body weight, and a low Apgar score with subclinical hypothyroidism. Evaluating the strength of the association between hypothyroidism and pregnancy outcome variables may help unify screening and subsequent management of hypothyroid pregnant women.
Keywords: pregnant women, III trimester, thyroid dysfunction, thyroid hormones, thyroid stimulating hormone, odds ratio

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