Сoncentration of sex hormones and dopamine in different groups of women in the Arctic depending on the phase of the menstrual cycle

INTRODUCTION: The transition of the indigenous population of the North from a nomadic to a sedentary lifestyle leads to a change in a number of regulatory mechanisms, which can affect the reproductive health of the female population.

AIM: To study the state of the hypothalamus-pituitary-gonad system and the level of dopamine in women in the Arctic zone of the Russian Federation, taking into account the phase of the menstrual cycle and the fact that the women belong to different groups of the population during the period of rapid transition of aborigines from nomadic to settled life.

MATERIAL AND METHODS: This article is an observational, cross-sectional, uncontrolled study that examines the differences in sex hormone concentrations and dopamine levels between groups of nomadic and sedentary aborigines and the local Caucasian population in the follicular and luteal phases of the menstrual cycle. A total of 157 women aged 23 to 51 years were examined. The concentrations of the main sex hormones, the sex hormone-binding globulin (SHBG), antisperm antibodies, and dopamine were determined by enzyme immunoassay. Statistical processing was performed using Statistica 10.0. Nonparametric methods of analysis were used because the majority of the obtained samples did not have a normal distribution (as assessed by the Shapiro–Wilk test). The threshold value of the significance level (p) was equal to 0.05. The significance of differences between groups was assessed using the Mann–Whitney U-test.

RESULTS: The differences between the groups were very similar in different phases. The follicle-stimulating hormone in the local Caucasian population was 1.5 to 2 times higher, and prolactin and antisperm antibodies were 1.5 to 2 times lower than in the aboriginal population groups, when 43% to 50% of individuals with dopamine values below normal were detected. Total and free testosterone were also lower in sedentary natives compared with other groups, and SHBG was higher (42–64% of cases above normal).

CONCLUSION: The features of the state of the hypothalamus-pituitary-gonad system, depending on the lifestyle, can contribute to the implementation of diagnostic and preventive measures while maintaining reproductive health in different groups of the Arctic population.