Fracture Risks Related to Parity and Breastfeeding Effect in Post-Menopausal Women Aged Sixty and Over: Results from the “Quality of Bone in Lorraine” Register

Abstract

Introduction: The long term effect of accumulation of genital events as repeated pregnancy and longer breastfeeding in bone heath later in women’s life is still disputed. The objective was to assess the impact of parity and cumulated duration of breastfeeding on fracture risk in post-menopausal women aged sixty an over. Patients and Methods: It was a leading study from the register “Quality of Bone in Lorraine (QBL)” achieved in the department of endocrinology and osteoporotic disease of Nancy (France). This register included all patients sent for an assessment of the bone mass density from January 1, 2006 to December 31, 2014 (9 years). It was about post-menopausal women aged sixty an over suffering or not from osteoporosis fracture or bone fragility just after the age of 45. The genital events of patients to their age (from puberty to menopause) as well as the existence of hormone replacement therapy use, parity, and breastfeeding duration were taken into account. The assessment of bone fracture was clinical, radiological or by using the vertebral fracture assessment method. Results: 861 post-menopausal women were included. In comparison to the control group, the fractured population had a mean age of (74.3 ± 9 vs. 72 ± 8 years), a family history of fracture (32.1% vs. 26%), and an average input of calcium (2.4 ± 1 vs. 2.3 ± 0 portions per day). The age at menarche was of 12.8 ± 1 years in each group, a mean genital activity duration of (36.8 ± 3 vs. 37.2 ± 3 years), a parity of (2.1 ± 1 vs. 1.8 ± 1 children), a cumulated breastfeeding duration (4.2 ± 16 vs. 3.1 ± 5 months) and an age of menopause of (48.6 ± 4 vs. 48.6 ± 4 years) were respectively found in fractured and witness population. Overall, an osteoporotic fracture has been rediscovered in 50.9%. In multivariate analysis, only a cumulative duration of breastfeeding of 6 months and over was associated with a higher fracture risk (OR = 1.5 [1.1 - 2.2]). The impact of parity was not significant (OR = 1.1 [0.7 - 1.8]). Association with obesity was quasi significant (OR = 1.3 [0.9 - 1.9]). There was no correlation between the fracture risk and the genital activity duration (OR = 0.7 [0.5 - 1.0]), hormone replacement therapy use (OR = 1.0 [0.8 - 1.4]), daily calcium input (OR = 0.8 [0.6 - 1.3]), and age of menarche (OR = 1.0 [0.9 - 1.1]). Conclusion: This work confirms a negative impact from 6 months of cumulative breastfeeding. The modest effects observed may be related to the selection of Caucasian patients who live in an economically developed country with a limited number of pregnancies and limited duration of breastfeeding.