Reproductive history in relation to relative weight and fat distribution.

Objective: To investigate the relationship between reproductive history and body composition.
Design: Prospective population study in Sweden.
Subjects: 1462 randomly selected women representing five separate age cohorts (38, 46, 50, 54 and 60 at the 1968-1969 baseline examination) have been followed longitudinally.
Measurements: Relative weight, fat distribution, and fat cellularity were related to menarche, parity, lactation, menopause and oestrogen medication.
Results: Age of menarche did not show any association with subsequent fat distribution, nor did length of lactation time. On the other hand parity was positively associated to total as well as central obesity, and lactation time was positively associated to abdominal fat cell diameter. Premenopausal women showed higher mean body weight and hip circumference than postmenopausal women of the same age. Change from pre- to postmenopausal status was associated with increase of waist circumference as well as reduction of hip circumference, resulting in an increased waist-hip ratio (WHR). Oestrogen replacement suggested some postponement of this increase.
Conclusion: Parity and menopause are the reproductive factors most associated with gradual changes in body fat distribution. Oestrogen medication seems to play an additional role in diminishing waist circumference increase and could thus contribute to decreased cardiovascular morbidity in women.