Age at menarche in Nigerian athletes

Association of Age at Menarche with Anthropometric Measures in Punjabi Bania Girls

INTRODUCTION

Menarcheal age is the age at which menstruation begins. Menarcheal age is regarded as a sensitive indicator of physical, biological and psychological environment.

AIM

1) To determine the menarcheal age and to examine the relationship between current age at menarche with anthropometric measures in Punjabi bania girls. 2) To develop maturity standards for Bania girls.

MATERIALS AND METHODS

The present cross-sectional survey was carried out on 200 bania girls at the age of onset of menarche. Menarcheal data was obtained by status quo method by asking about whether menarche has been experienced or not. In the present survey adolescent girls were interviewed with the help of pre-designed questionnaire. Statistical analysis was carried out in SPSS software, version 16.0. The data were analysed using descriptive statistics and one-way ANOVA. Pearson's correlation coefficient was used for correlation studies.

RESULTS

A total of 200 Punjabi bania girls were examined in the study. The median age of onset of menarche in these girls was 12.3 years. Menarcheal age was positively associated with bi-acromial width, bi-iliac width and arm span.

CONCLUSION

The present research has revealed secular trend in the age of onset of menarche as indicated by median age of 12.3 years in Bania girls. The bi-acromial width, bi-iliac width and arm span were also correlated with the age of menarche.

Longitudinal estimates of puberty timing in Senegalese adolescent girls

This study aimed to assess the timing of sexual maturation (breast development and menarche occurrence) among sub-Saharan African adolescent girls from rural areas. In the framework of a longitudinal study of growth at puberty, the stages of pubertal development (Tanner classification) and menarche occurrence were recorded at intervals between 1995 and 2000 in a sample of 406 Senegalese adolescent girls from a rural area. Nutritional status was estimated during infancy, childhood, and adolescence within this sample, and body composition was estimated only during adolescence. At the beginning of the study (1995), the adolescent girls were 11.4 years old (SD = 0.6). At the end of the study, they were 16.5 years old (SD = 0.6). Median and quartile ages at entry into each maturity stage and its confidence limits were estimated by a lognormal parametric survival model. These adolescent girls were shorter and thinner than girls of the same age from developed countries. Median age at the onset of breast development was 12.6 years (95% CI = 12.5-12.8). Median age at the end of sexual maturation and median age at menarche were estimated respectively at 15.8 years (95% CI = 15.7-15.9) and 15.9 years (95% CI = 15.7-15.9). These adolescent girls were less mature than other adolescent girls of the same age from other developing countries. Their puberty was extremely delayed compared to that of adolescent girls of the same age from industrialized countries. Puberty in these Senegalese adolescent girls is delayed by about 3 years. This may be due to malnutrition, significant energy expenditure, and poor diet and living conditions, and possibly to genetic control.

Menarcheal age among Indian sportswomen

The subjects of the study were 85 Indian sportswomen from Delhi and the states of Uttar Pradesh, Punjab and Gujarat, and included outstanding players of cricket, hockey, kho-kho and table-tennis, who were winners of university, state or national championships. A sample of 77 subjects selected at random was used as the control. The recall procedures suggested by Damon and Bajema (1974) were used. The combined mean age at menarche for sportswomen is 13.56 years and for the control sample is 12.7 years. Menarche was significantly delayed in those sportswomen who embarked on physical training activities before the onset of menstruation. There are also variations in the mean menarcheal age between participants in different sports specialities.

Menstrual dysfunction in Nigerian athletes

Menstrual function was assessed in 475 Nigerian athletes in different sports and 606 non-athletes. In general, irregular menstrual cycles and oligomenorrhoea or secondary amenorrhoea (O/A) were more common in the athletes (26% and 21%, respectively) than in the non-athletes (18% and 8%, respectively). Menstruation was more regular and normal in the non-athletes (50%) than in the athletes (22%). It was noted that menstrual dysfunction in the athletes was associated with significantly low body fat, body weight, relative weight for height, and the stress of sports activity. In the groups of athletes the ball game players (35%) and distance runners (51%) most commonly experienced O/A, whereas the incidence of dysmenorrhoea and menorrhagia was most prevalent in the swimmers (37%), and sprinters (42%). Menstrual disturbances were relatively more common in athletes who began training before the menarche (43%).

A hypothesis on the role of pheromones on age of menarche

Over the last century and a half there has been a secular decline in the age of menarche in Western, industrialized cultures. This trend has been largely ascribed to improved nutrition and health, and we offer an alternative hypothesis that changes in socio-economic conditions have resulted in changes in the pheromonal climate to which prepubertal females are exposed, thereby affecting onset of menarche. Extensive data from non-human mammalian studies indicate that puberty in females is delayed by exposure to adult females, and accelerated by exposure to adult males. The mechanism is pheromonal. The pheromonal climate of the home may have changed since mothers are in the home less (more women now work) and fathers are in the home more (work day of 8 rather than 14 hr). Assuming humans respond similarly to pheromones, this change would contribute to a decline in age of menarche.