Longitudinal estimates of puberty timing in Senegalese adolescent girls

Abstract

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.

Fat and muscle mass in different groups of pre-pubertal and pubertal rural children. Cross-cultural comparisons between Sahelian (rural Senegal) and Amazonian (Beni River, Bolivia) children

“…Indeed, very slow maturation has been reported in girls from Senegal, a Sahelian country of West Africa, where adolescent girls had a median age of 16.1 years at menarche (Simondon et al 1997). This delay was later confirmed by a longitudinal study (Garnier et al 2005). Boys also presented very slow growth during pubescence (Benefice 2007).…”

“…Likewise, analysis of age at first menstruation using a national representative sample of girls confirmed that Senegalese girls menstruated later than in industrialized countries (upper limit: 12.8 years of age) (Adair and Gordon-Larsen 2001).This figure should be compared to 15.9 years (CI 95%, 15.7~16.0) currently. In addition, the onset of puberty, as assessed by breast development (B2 stage according to Tanner's classification) was 12.6 years (CI 95% : 12.5~12.8) (Garnier et al 2005). In the USA, it occurs 1.5 to 2 years earlier (Sun et al 2002).…”

“…Longitudinal observations of adolescent Senegalese girls permits precise estimation using a log normal parametric survival model (Garnier et al 2005). In Bolivia, a status quo method was used in all girls older then 10 and a probit analysis done.…”

Telarquia y estado nutricional: Estudio epidemiológico en dos grupos étnicos

“…La asociación de menor talla con retraso en la telarquia está en concordancia con el atraso de edad ósea y por tanto de los eventos puberales observados en niñas desnutridas 30 . En relación a estos resultados, se hace necesario el estudio de la velocidad de crecimiento entre eventos puberales, en niñas con exceso de peso y con déficit de talla, dado que pueden terminar con estaturas muy distintas influenciadas no sólo por el momento en que ocurren los eventos puberales sino por el estado nutricional con el cual se inicia esta etapa del desarrollo.…”

Pubertal breast development in primary school girls in Sokoto, North-western Nigeria

“…Few studies on pubertal onset have been conducted on African children living in Africa. [13,14] The influence of environment and geographical location on pubertal timing has been previously documented. [15,16] Most Nigerian studies have focused on age at menarche and influencing factors.…”