Objective — to study the impact of threatened abortion on fetoplacental complex function during prolonged pregnancy with a male fetus. Subject and methods. The investigation enrolled 124 pregnant women at 30—34 weeks’ gestation. Group 1 included 44 patients with a male fetus, whose pregnancy was complicated by threatened miscarriage in the first-trimester. Group 2 and 3 consisted of 40 women in each who had physiological pregnancy with a male or female fetus, respectively. Ultrasonography was performed on the Voluson 730 Pro system (Austria), by applying 3.5—5.0-MHz broadband convex probes. Hormonal profiles were measured from the progesterone, estradiol, cortisol, and testosterone concentrations determined by enzyme immunoassay in the peripheral venous blood of pregnant women, by employing the company’s commercial sets. Results. The emergence of clinical manifestations of threatened abortion leads to minor changes in the fetometric parameters of male fetuses during pregnancy prolongation and their determination at 30—34 weeks’ gestation, but is accompanied by significantly higher peripheral resistance indices of uterine arteries, by increasing the frequency of grade IA uteroplacental blood flow impairment to 36.4%, thinning of the placenta up to 20.45%, and its premature maturation up to 18.2%. Group 1 exhibited a significant decrease in the serum levels of progesterone and testosterone in pregnant women with a male fetus in the presence of elevated estradiol and cortisol concentrations, which is reflected not only in pregnancy outcomes, but also may affect the development of fetal reproductive organs. Conclusion. A complicated pregnancy during the first trimester has a negative impact on fetoplacental complex function in pregnant women carrying a male fetus, by increasing the risk of premature birth up to 22.7%.