SHORT REPORT Age at menarche of schoolgirls in Maputo, Mozambique C. Padez Departamento de Antropologia, Universidade de Coimbra, 3000-056 Coimbra, Portugal Received 18 November 2002; in revised form 25 February 2003; accepted 4 March 2003 Summary. Age at menarche was analysed in 753 Mozambican schoolgirls taking part in a cross-sectional anthropometric study in Maputo, Mozambique, in 2000. The probit analysis of the status quo data yielded an median age at menarche of 13.20  1.18 years. The retro- spective method was applied only to recall data of the 396 post-menarcheal girls and it yielded an average of 13.9  1.29 years. Mean age at menarche in girls living in the urban centre of Maputo was 13.35 and 12.96 years, for recall age and probit analysis, respectively, and 14.51 and 13.68 years for girls living in the slums surrounding the centre. The diﬀerences in age at menarche, calculated by recall method, between girls from central Maputo and girls from the slums were statistically signiﬁcant ( p ¼ 0.0). Parent’s educational level also revealed a signiﬁcant eﬀect on age at menarche. Girls whose parents had a lower educational level showed a later age at menarche. For the size of the family, girls who were later borne had a higher age at menarche. In the 1960s, the age at menarche was 13.55 and 13.83 years in urban and rural girls, respectively. In this study, we found a lack of decrease in the mean age at menarche (13.9 years), which could be due to the poor living conditions in Mozambique between 1960 and 2000 as a result of the civil war from 1976 to 1990. Despite the economic growth of the country in the last decade, Mozambique is still in the group of the poorest countries in the world; in spite of this fact, the mean menarcheal age in these girls are amongst the lowest values presented for African countries. 1. Introduction Age at menarche, the ﬁrst menstrual period, is an important maturity indicator to assess the developmental status of a pubertal female (Cameron and Nadgdee 1996). This biological event is the outcome of a number of social and biological factors, and the mean menarcheal age appears to be a particularly sensitive indicator of the biosocial status of a population (Lindgren 1976, Bielicki and Welon 1982, Laska-Mierzejewska et al. 1982, Dann and Roberts 1993, Vienna and Capucci 1994). Age at menarche is known to be inﬂuenced by genetic factors (Loesch et al. 1995, Meyer et al. 1991) and by socio-economic variables such as the degree of urbaniza- tion (Pasquet et al. 1999), the socio-economic status (Henneberg and Louw 1995), the size of the family and the order of birth (Apraiz 1999). Other factors like nutrition (Simodon et al. 1997), seasonality (Boldsen 1992), physical activity (Malina 1983), and altitude (Gonzales et al. 1996) also showed a signiﬁcant eﬀect on age at menarche. In recent reviews of published studies on the variability of age at menarche throughout the world, Thomas et al. (2001) found that the factors that best explained the variation in age at menarche were adult illiteracy rate and vegetable caloric consumption. At present, almost all industrialized countries do not show any statistically signiﬁcant diﬀerences in mean age at menarche for diﬀerent FIRST PROOFS 28/4/03 ag Annals of Human Biology {TandF}Tahb/TAHB-100544.3d Paper 100544 Page 1 Keyword ANNALS OF HUMAN BIOLOGY, 200?, VOL. ??, NO. ?, 1–9 Annals of Human Biology ISSN 0301–4460 print/ISSN 1464–5033 online # 200? Taylor & Francis Ltd http://www.tandf.co.uk/journals DOI: 10.1080/0301446031000111401 1 2 3