Introduction. One of the most common drugs for maintaining pregnancy is exogenous progesterone. With the expansion of the indications for its use during pregnancy, the number of complications associated with it may increase. Material and methods. The article presents the results of a prospective study of medical records of pregnant women, which were observed in the V.F. Snegirev Obstetrics and Gynecology Clinic in 2017 and received exogenous progesterone therapy. Results. The dynamics of changes in the studied biochemical parameters was multidirectional in the main and control groups. According to pregnancy outcomes, statistically significant differences between the groups were not found. Conclusions. Critical abnormalities of the main biochemical parameters in pregnant women of the main group were not detected. Preparations of the gestagen series in appropriate dosages do not significantly affect the main indicators of the hepatobiliary system and pregnancy outcomes, so their use is permissible under the control of laboratory parameters.