Objective. Often symptom of hyperprolactinemia are various types of menstrual flow disorder Methods & patients. We studied & analyzed the frequency and characteristics of the menstrual flow disorder among the women we examined (96 women) and performed genotyping of polymorphism C3420T of the DRD2 gene. The examined women divided in 3 groups: 1) Women with hyperprolactinemia with the context of the pituitary microadenoma 2) Women with functional hyperprolactinemia 3) Other pathology of the pituitary Main Outcomes. Group1: Infertility I - in 15% of women (CC-genotype -17%, СT genotype -83%), Infertility II - in 10.2% (СС genotype -25%, СT genotype -50%, TT genotype -25%), menstrual flow disorder -36% of women (CC genotype -21,4%, CT genotype -57,2%, TT genotype -21,4%). Among them, oligoopsomenorrhea in 3 women (CT genotype-2, TT genotype-1), polymenorrhea -1 woman (CT genotype), oligomenorrhea -1 woman (CC genotype), Amenorrhea -2 women (CT genotype and TT genotype), Algodismenorea -5 women(CT genotype-4, CC genotype-1). Group 2: Infertility I - in 21.5% of women (CC-genotype -36.3%, CT-genotype -54.5%, TT genotype -9%), Infertility II - in 6% (CC genotype -66%, CT genotype -33%), menstrual flow disorder -39.2% of women (CC genotype -30%, CT genotype -70%). Of these, oligoopsomenorrhea in 8 women (CT genotype-7, CC-genotype-1), Opsomenorrhea -4 women (CC genotype-2, CT genotype-2), Oligomenorea-3 women (CC genotype-2, CT genotype-1), amenorrhea-2 women (CT genotype-2), algodismenorrhea -3 (CT genotype 2 women, CC genotype -1). Group 3: CC genotype-2, CT-4 women. Infertility was not observed in this group, but 5 women had menstrual flow disorder, polymenorrhea - 1(CT genotype), oligomenorrhea - 3(CC genotype - 2, CT genotype - 1), algodismenorrhea - 1(CT genotype). Results & Conclusions: 1-In all of the researched groups, the CT genotype predominates. 2-In women with Infertility-I in the group with hyperprolactinemia of organic genesis, the CT genotype is much more prevalent compared to group 2 of functional genesis (83.3% and 54.5%, respectively). 3-In women with Infertility-II, the number of carriers of the CT genotype in the group with the pituitary microadenoma is greater than in the group without organic changes. (50% and 33%). In the group of women with amenorrhea revealed CT genotype (75%) and TT genotype (25%), it is remarkable that the pathological TT genotype in women with hyperprolactinemia against the background of the pituitary microadenoma.