Abstract
Menstrual function was assessed comparatively in different categories of 155 Nigerian
athletes, aged 13-19 years, and 135 nonathletes, aged 12-18 years, who answered questionnaires
and were interviewed. Menstruation was more regular and normal in the nonathletes
(44%) than the athletes (21%). Although both groups generally had similar patterns
of menstrual dysfunction, secondary amenorrhea or oligomenorrhea (O/A) was more prevalent
in the athletes (25%) than the nonathletes (10%). Among the athletes, only the distance
runners strikingly (35%) reported experiencing O/A. Distance runners were significantly
lighter and leaner than nonathletes and athletes of other sports (P<0.05). Regardless of sports activity, oligomenorrheic subjects had substantially
lower body weight relative to stature and were leaner than subjects of the other menstrual
categories. In the oligomenorrheic group, a greater proportion of the athletes (59%)
and nonathletes (57%) had lean body mass values below the 41st percentile. The pre-menarche-trained
athletes (48%) reported a higher incidence of menstrual cycle irregularities than
the athletes who began training after the menarche. Results support the role of body
composition-related factors in the etiology of exercise-associated O/A.
Key words
regular competitive sports - menstruation - menstrual disorders - body composition
