The article presents the results of examination of 156 women from infertile couples (88 Russians, 68 Buryats). The uterine factor of infertility was observed more often in Buryats due to higher rate of uterine fibroids in Buryat women with secondary infertility in comparison with Russian infertile women: 69,7 % and 21,8 %, respectively. No significant difference was shown in adenomyosis and endometrium hyperplasia frequency.

The antioxidant system of blood is the important factor that characterizes the adaptive possibilities of human organism. The estimation of state of the antioxidant protection and lipid peroxidation systems at men and women of two Baikal Lake ethnic groups was carried out. Spectrophotometric and fluorometric methods were used during the study. Increase of by-products of lipid peroxidation with decrease of activity of the antioxidant protection system was observed at men of the Buryat ethnicity in comparison with Russian ones. At women of the Buryat ethnicity was observed the increase of the primary products of lipid peroxidation with the adequate antioxidant response in comparison with Russian ones.

The article presents the frequency characteristics of polymorphisms *A *B *C, *D GSTP1 gene in women with endometriosis and healthy Russian and Buryat ethnic groups. The study shows that in the group of Russian AC genotype is more common in healthy women compared with patients with endometriosis (p = 0,02). Mutant allele *B was significantly more common among Russian women with endometriosis, compared with a group of Buryat with endometriosis (p = 0,05).

The article presents the results of the analysis of the distribution of genotypes and alleles of polymorphic loci gene GSTP1 (*A, *B, *C, *D), GSTT1 (del) and GSTM1 (del) in 28 women Russian and 30 women of Buryat ethnic groups. As a result, the work showed a statistically significant difference in genotype AC gene GSTP1 among the study groups. As carriers of other genotypes of genes GSTP1, GSTT1, and GSTM1 showed no significant difference

We studied parameters of lipid peroxidation (LPO) in women with infertility, resident of the Republic of Buryatia. The levels of malonic dialdehyde (MDA) were increased in the examined infertile women from Buryat and Russian populations. Reduced total antioxidant activity, activity of superoxide dismutase (SOD), and α-tocopherol levels were revealed in patients from Buryat population; decreased concentrations of reduced glutathione were recorded in patients from Russian populations.

In this article the results of endocrine infertility causes investigation in 110 women of reproductive age from infertile couples (60 Russian and 50 Buryat women) are presented. It is shown that endocrine infertility is often associated with tube and. peritoneal pathology (25,45 %) tube peritoneal and uterine factors (11,81 %) and with uterine factor only (10,9 %). There were no any differences in endocrine infertility causes structure depending on the ethnicity of patients.

In the article the results of infertility causes analysis in 638 cauples, visited respublic center of perinatology in 2004-2005 years are presented. It is established that the endocrine disorders and combination of the causes are the main factors of infertility.

We have examined 68 women of reproductive age with infertility, using the medical-diagnostic laparoscopy. Often salpingoovariolysis was used during operation, which was performed in 64,7 %.