e-Article
Estimated Ovulatory Years Prior to Menopause and Postmenopausal Endogenous Hormone Levels.
Document Type
Academic Journal
Author
Cramer DW; Obstetrics and Gynecology Epidemiology Center, Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, Massachusetts.; Harvard Medical School, Boston, Massachusetts.; Vitonis AF; Obstetrics and Gynecology Epidemiology Center, Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, Massachusetts.; Huang T; Harvard Medical School, Boston, Massachusetts.; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.; Shafrir AL; Division of Adolescent/Young Adult Medicine, Department of Pediatrics, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts.; Eliassen AH; Harvard Medical School, Boston, Massachusetts.; Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.; Departments of Nutrition and Epidemiology, Harvard TH Chan School of Public Health, Boston, Massachusetts.; Barbieri RL; Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, Massachusetts.; Hankinson SE; Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, Massachusetts.
Source
Publisher: American Association for Cancer Research Country of Publication: United States NLM ID: 9200608 Publication Model: Print Cited Medium: Internet ISSN: 1538-7755 (Electronic) Linking ISSN: 10559965 NLM ISO Abbreviation: Cancer Epidemiol Biomarkers Prev Subsets: MEDLINE
Subject
Language
English
Abstract
Background: Lifetime ovulatory years (LOY) is estimated by the difference between ages at menopause and menarche subtracting time for events interrupting ovulation. We tested whether LOY influences sex hormone levels in postmenopausal women with at least one intact ovary not using hormones.
Methods: Estradiol, estrone, estrone sulfate, total testosterone, dehydroepiandrostendione sulfate, prolactin, and sex hormone binding globulin were measured in 1,976 postmenopausal women from the Nurses' Health Study. Associations of age, body mass index (BMI), smoking, alcohol use, and other factors on hormones were assessed by t tests and ANOVA. Linear regression was used to assess multivariable adjusted associations between LOY and hormones and trends in hormone levels per 5-year increases in LOY were estimated.
Results: Women averaged 61.4 years old, 11.0 years since menopause, with BMI of 25.8 kg/m2. A total of 13.6% had irregular cycles, 17.5% hysterectomy, 6.4% unilateral oophorectomy, and 13.8% were current smokers. Variables associated with one or more hormone levels were included as covariates. Each 5-year increase in LOY was significantly associated with a 5.2% increase in testosterone in women with BMI < 25 kg/m2 and a 7.4% increase in testosterone and 7.3% increase in estradiol in women with above-average BMI.
Conclusions: This is the first study to show that greater LOY is associated with higher testosterone in postmenopausal women and higher estradiol in those with elevated BMI, suggesting accumulation of functioning stromal and thecal cells from repeated ovulations and peripheral conversion of testosterone.
Impact: A possible explanation for why greater LOY increases risk for breast, endometrial, and ovarian cancer is offered.
(©2023 American Association for Cancer Research.)
Methods: Estradiol, estrone, estrone sulfate, total testosterone, dehydroepiandrostendione sulfate, prolactin, and sex hormone binding globulin were measured in 1,976 postmenopausal women from the Nurses' Health Study. Associations of age, body mass index (BMI), smoking, alcohol use, and other factors on hormones were assessed by t tests and ANOVA. Linear regression was used to assess multivariable adjusted associations between LOY and hormones and trends in hormone levels per 5-year increases in LOY were estimated.
Results: Women averaged 61.4 years old, 11.0 years since menopause, with BMI of 25.8 kg/m2. A total of 13.6% had irregular cycles, 17.5% hysterectomy, 6.4% unilateral oophorectomy, and 13.8% were current smokers. Variables associated with one or more hormone levels were included as covariates. Each 5-year increase in LOY was significantly associated with a 5.2% increase in testosterone in women with BMI < 25 kg/m2 and a 7.4% increase in testosterone and 7.3% increase in estradiol in women with above-average BMI.
Conclusions: This is the first study to show that greater LOY is associated with higher testosterone in postmenopausal women and higher estradiol in those with elevated BMI, suggesting accumulation of functioning stromal and thecal cells from repeated ovulations and peripheral conversion of testosterone.
Impact: A possible explanation for why greater LOY increases risk for breast, endometrial, and ovarian cancer is offered.
(©2023 American Association for Cancer Research.)