The Effect of Lactation and First Gestational Age on Postmenopausal Osteoporosis

Objective: Several factors have been suggested in the etiology of postmenopausal osteoporosis (OP). This study aims to investigate the effect of number of pregnancies, lactation, and first gestational age on postmenopausal OP. Methods: A total of 427 postmenopausal patients between 45 and 70 years of age who underwent OP scan between April 2015 and December 2015 were included. A questionnaire was administered to all patients to obtain data including age, height, weight, menopause and menarche ages, chronic illnesses, concomitant medications, family history, postmenopausal hormone therapy, number of pregnancies, ages at birth, and lactation periods at each pregnancy. The bone mineral density (BMD) was measured using dual-energy X-ray absorptiometry from femoral neck and total femur and from the lumbar vertebrae L1-L4 and L2-L4 were recorded. The patients were divided into two groups as those with OP (n=73) and those without OP (n=354). Results: The number of pregnancies was statistically higher in the OP group, compared to the non-OP group (p=0.037). According to the nulliparity, primiparity, and multiparity, there was no significant difference between the groups. Conclusion: Our study results suggest that lactation period and first gestational age have no effect in the development of postmenopausal OP