Study group  Inclusion criteria:  primary infertility (unsuccessfully trying to become pregnant for more than a year) regular menstruation  Exclusion criteria:  female homronal therapy established male factor of infertility tubal factor endometriosis inflammation in the pelvic area - currently and in the history hormonal background of infertility obesity insulin resistance status post at least one miscarriage chronic autoimmune diseases.  Control group  Inclusion criteria:  naturally conceived offspring up to three years of age regular menstruation  Exclusion criteria were:  status post surgery on the uterus, including curettage of the uterine cavity endometriosis pelvic inflammation - present and in the history at least one miscarriage obesity insulin resistance chronic autoimmune diseases breastfeeding.