Breast Cancer Risk Factors and Circulating Anti-Mullerian Hormone Concentration in Healthy Premenopausal Women

Context: We previously reported that anti-Mullerian hormone (AMH), a marker of ovarian reserve, is positively associated with breast cancer risk, consistent with other studies. Objective: This study assessed whether risk factors for breast cancer are correlates of AMH concentration. Methods: This cross-sectional study included 3831 healthy premenopausal women (aged 21-57, 87% aged 35-49) from 10 cohort studies among the general population. Results: Adjusting for age and cohort, AMH positively associated with age at menarche (P<0.0001) and parity (P=0.0008) and inversely associated with hysterectomy/partial oophorectomy (P=0.0008). Compared with women of normal weight, AMH was lower (relative geometric mean difference 27%, P<0.0001) among women who were obese. Current oral contraceptive (OC) use and current/former smoking were associated with lower AMH concentration than never use (40% and 12% lower, respectively, P<0.0001). We observed higher AMH concentrations among women who had had a benign breast biopsy (15% higher, P=0.03), a surrogate for benign breast disease, an association that has not been reported. In analyses stratified by age (<40 vs >= 40), associations of AMH with body mass index and OCs were similar in younger and older women, while associations with the other factors (menarche, parity, hysterectomy/partial oophorectomy, smoking, and benign breast biopsy) were limited to women >= 40 (P-interaction <0.05). Conclusion: This is the largest study of AMH and breast cancer risk factors among women from the general population (not presenting with infertility), and it suggests that most associations are limited to women over 40, who are approaching menopause and whose AMH concentration is declining.

Automated summary

This study found positive associations between AMH and age at menarche and parity, and negative associations with hysterectomy/partial oophorectomy. Women who were obese, currently used oral contraceptives, or were current/former smokers had lower AMH concentrations. Interestingly, higher AMH concentrations were observed in women who had a benign breast biopsy, especially in women over 40 years old.