Measures of menopause driven differences in levels of blood lipids, follicle-stimulating hormone, and luteinizing hormone in women aged 35 to 60 years: National Health and Nutrition Examination Survey III and National Health and Nutrition Examination Survey 1999-2002 study.

Objective: The purpose of this cross-sectional study was to assess the association of the menopausal transition with differences in lipid and endogenous hormone levels in normal [18.5 kg/m² ≤ body mass index (BMI) ≤ 24.99 kg/m] and overweight (BMI >24.99 kg/m²) women.

Methods: The study was conducted on women age 35 to 60 years from the Third National Health and Nutrition Examination Survey and from the National Health and Nutrition Examination Survey surveys conducted between the years 1999 and 2002. Menstrual cycle-based menopause status was defined for women who had not had surgical menopause, did not use contraceptives, did not smoke, and did not breast-feed during the examination, by months since the last period (<2, 2-12, and >12 mo for premenopause, perimenopause, and postmenopause, respectively).

Results: There were no significant differences in age-adjusted total cholesterol, triglyceride, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol levels among the menopausal periods in the normal BMI class. The pattern of differences in the high-density lipoprotein cholesterol level differed between the normal and obese BMI classes. The activity of luteinizing hormone and follicle-stimulating hormone was statistically different between premenopause and perimenopause and premenopause and postmenopause in the normal BMI class. A different picture was observed for the analysis of differences in raw parameters. In this case more differences between menopausal phases were observed for all of the studied parameters.

Conclusions: Aging plays a role at least as important as menopause during the menopausal transition. However, at the current stage, it is impossible to assess the relative weights of aging and the menopausal transition on the differences in the studied parameters.