Multiple births increase fracture risk after menopause; cause identified

Women who have experienced multiple childbirths face a higher likelihood of bone fractures after menopause compared to those who have never been pregnant, according to a new study. The research, presented by Dr. Sung Gyeong-heon, a resident physician at Seoul St. Mary's Hospital, at the 2026 Seoul Symposium on Bone Health, has statistically validated this link.

The study analyzed data from 1,420 postmenopausal women using the 2024 Korea National Health and Nutrition Examination Survey. It found that women with three or more childbirths had approximately a 36% higher probability of experiencing fractures post-menopause than women who had never given birth. This increased risk was confirmed to be statistically significant.

Researchers identified the "estrogen gap" during pregnancy and breastfeeding as a primary physiological mechanism. During these periods, menstruation ceases, reducing the cumulative exposure to estrogen, a hormone crucial for bone tissue preservation and maintaining bone density. This reduction in estrogen exposure over a lifetime is believed to contribute to the heightened fracture risk.

However, the study also noted that multiple pregnancies are not solely detrimental to women's health. Previous research indicates that a higher number of childbirths may correlate with a reduced risk of hormone receptor-positive breast and ovarian cancers. Therefore, multiple births are considered a complex health factor with both potential risks and benefits. The findings underscore the importance of preventive management, particularly regarding bone health, for women with multiple childbirth experiences.