The effect of vitamin D on the microbiocenosis of the genital tract in women with multiple pregnancies




vitamin D deficiency, microbiocenosis, multiple pregnancy, vaginal ecosystem, assisted reproductive technologies, women


Insufficiency of vitamin D during pregnancy was and remains one of the urgent problems of modern obstetric practice, which focuses on itself the attention of researchers from different countries.

The importance of the issue of multiple pregnancy (МР) is determined by the significant number of complications that may arise during pregnancy, childbirth and the postpartum period. Possessing an immunomodulatory and anti-inflammatory effect, vitamin D ensures not only implantation, placentation, but also the course of the entire multiple pregnancy. Microbiocenosis of the female genital tract is a marker of the overall health of the female body, the issue of its disruption under the influence of vitamin D deficiency is of particular scientific interest.

Purpose - to study the peculiarities of the genital tract microbiocenosis in women with multiple pregnancies and vitamin D deficiency.

Materials and methods. Were examined 120 pregnant women, 90 of whom had multiple pregnancies and vitamin D deficiency, and were divided into two groups depending on the onset of pregnancy: the Group I consisted of 48 women with multiple births as a result of assisted reproductive technologies, and the Group II consisted of 42 pregnant women with spontaneous multiple births. The control group consisted of 30 healthy women with a singleton pregnancy and a normal level of 25(OH)D. The content of vitamin D in blood serum was studied by the immunoenzymatic method in the first and second trimesters of pregnancy. Microbiocenosis of the vagina of examined pregnant women was studied on the basis of bacterioscopic and bacteriological research.

Results. A deviation in the ratio between cocci and bacilli flora was found in the I and II trimesters of pregnancy. The predominance of cocci flora was observed in women with multifertility due to the use of assisted reproductive technologies (55.9%), compared to women of the Group II (22.6%) and the control group (18.4%), which indicates the presence of inflammatory processes caused by vitamin D deficiency in this contingent of pregnant women, both in the first and second trimesters of pregnancy. The high activity of pro-inflammatory cytokines, which activate proteolytic enzymes in the vagina of pregnant women under the influence of vitamin D deficiency, causes the inflammatory process, thereby disrupting the vaginal microbiocenosis of pregnant women with MP.

Conclusions. Violations of the microbiocenosis of the genital tract in women with MP in the early stages of pregnancy indicate that vitamin D deficiency plays a leading role in the genesis of inflammatory changes in the vaginal ecosystem.

Early detection and timely treatment of vitamin D deficiency will contribute to reducing the number of violations of vaginal microbiocenosis and, as a result, prolongation of multiple pregnancies due to the use of assisted reproductive technologies.

The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of participating institution. The informed consent of the patient was obtained for conducting the studies.

No conflict of interest was declared by the authors.


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