Biosocial determinants of age at menarche among secondary school girls in Benin City

Abstract

Background: Menarche signals reproductive maturity and the earlier the menarche, the earlier the initiation of sexual activity with the implication of increase in teenage sexuality and its complications.

Aim: To determine the age at menarche among girls in Benin City and to establish its biosocial determinants.

Method: This was a cross – sectional descriptive study of secondary school girls in Benin City. Data was collected with the aid ofself-administered questionnaires. Biophysical parameters of the study population were also obtained. Age at menarche was compared with biosocial indices.

Results: Of the 1830 respondents, 1322 (72.2%) had attained menarche. The mean age at menarche of the population was 12.72 ± 1.24 years. The menarcheal age was lowest in social class 1 (12.3 ± 1.16) and highest in social class 5 (14.09 ± 0.85), P = 0.000. Girls from polygamous homes had significantly higher age at menarche compared to girls from monogamous homes (13.22 ± 1.25 vs 12.62 ± 1.22 years, P = 0.000). As the number of siblings increased, there was significant increase in the age at menarche (P = 0.000). Post menarcheal girls had significantly higher mean body weight, height, BMI and mid arm circumference.

Conclusion: The age at menarche in Benin City school girls is 12.72 ± 1.24 years. The socioeconomic and nutritional status influence the age of menarche.

Keywords: Menarche, age, determinants, biosocial