Natural menopause occurring 1.5 years later than in 1959
The mean age for natural menopause and mean reproductive life span both increased for women during a 60-year period from 1959 to 2018, according to a research letter published in JAMA.
“Understanding changes in the timing of age at natural menopause and length of the reproductive life span and associated factors are important, because these factors influence multiple health conditions,” Duke Appiah, PhD, MPH, assistant professor and director of the master of public health program, department of public health at the Texas Tech University Health Sciences Center, told Healio. “For instance, earlier age at natural menopause is reported to be associated with cardiovascular diseases, neurological diseases and osteoporosis risk, while later menopause has been associated with increased risk for breast, endometrial and ovarian cancers. Overall, longer reproductive life spans are associated with reduced morbidity and mortality.”
Researchers extracted data from successive surveys starting from the National Health Examination Survey I (NHES I) conducted from 1959 to 1962 to the National Health and Nutrition Examination Survey for 2017-2018. Women aged 40 to 74 years who had natural menopause and reported their age at menopause were included. Age at menarche and age at menopause were both self-reported in the surveys.
There were 7,773 women included in the analysis. Participants in NHES I from 1959 to 1962 had a mean age at menopause of 48.4 years. Age at menopause increased over time, reaching a mean of 49.9 years for 2015 to 2018 (P < .001). Mean age at menarche was 13.5 years in 1959-1962 and decreased to 12.7 years in 2015-2018 (P < .001). The mean reproductive life span for women was at its lowest at 35 years in 1959-1962 and increased to 37.1 years in 2015-2018 (P < .001).
In adjusted data, Black (adjusted OR = 0.85; 95% CI, 0.72-1.01; P = .006) and Hispanic women (aOR = 0.7; 95% CI, 0.55-0.88; P = .006) were more likely to have natural menopause at an earlier age compared with white women. Women had greater odds for natural menopause at a younger age if they were in poverty (aOR = 0.83; 95% CI, 0.71-0.97; P = .02), a former smoker (aOR = 0.75; 95% CI, 0.63-0.88; P < .001), current smoker (aOR = 0.57; 95% CI, 0.47-0.69; P < .001) or used hormone therapy (aOR = 0.87; 95% CI, 0.75-1; P = .05). Women with an education level higher than high school (aOR = 1.36; 95% CI, 1.15-1.6; P < .001) and those who used oral contraceptives (aOR = 1.26; 95% CI, 1.08-1.48; P = .005) were more likely to have natural menopause at a later age. A higher education level and oral contraceptive use were also associated with a longer reproductive life span.
“Other factors, such as nutrition, environment and access to health care, that were not assessed in our study could also have contributed to these trends in age at natural menopause and reproductive lifespan,” Appiah said.
Appiah said future studies are needed to examine why age at natural menopause is associated with certain disease and whether it could be a marker for the overall health of women.
For more information:
Duke Appiah, PhD, MPH, can be reached at email@example.com.