Social background and age at menarche in Portuguese university students: A note on the secular changes in Portugal

Abstract

Menarcheal age of a sample of Portuguese university students (n = 3366), born between 1972 and 1983, age 18-23 years, was analyzed. The influence of parents' educational level and occupation, family size, birth order, and degree of urbanization of girl's locality of residence during childhood and adolescence were analyzed as well as secular trend in the Portuguese population. Mean age at menarche for girls born in 1983 was 12.32 years. Parents' educational level and occupation did not show any significant influence on mean age at menarche. Place of residence during childhood years and adolescence showed a significant effect on mean age at menarche, with girls from rural places with a later age at menarche than those who spent their childhood or adolescence in urban areas (P <or= 0.01 and P <or= 0.05 for childhood and adolescence, respectively). Family size and birth order showed the highest effect. Girls born in small families, with one child, matured earlier (12.32 years) than those born in large families with four or more children (12.67 years), (P <or= 0.01). Also, girls that were first-born had an earlier menarche (12.41 years) than those who were third or later (12.58 years, P <or= 0.01). Regression analysis selected family size and place of residence in childhood as the most important determinants of mean age at menarche in our university students. In this sample, from 1972 to 1983, mean age at menarche remained stable. When we considered published data from all the Portuguese population we found a decrease in mean age at menarche from 15 years for girls born in 1880 to 12.44 for those born in the 1980s. This decrease was the result of great improvements in the social and economic living conditions that occurred in Portugal especially after the 1970s concerning nutrition and health care, among many other environmental factors.

Secular trends in age at menarche among Caboclo populations from Pará, Amazonia, Brazil: 1930–1980

“…One of the most unexpected findings of this study is that there is no association between number of children in the family and age at menarche in the population studied. This result is contrary to some findings in other populations (Cameron and Nadge, 1996;Padez, 2003), and requires further investigation. In a rural community in Southeast Brazil, Tavares et al (2000) also did not find any difference in age at menarche in relation to number of children in the family, but other studies in Brazil (Riehmer and Violato, 1983;Silva et al, 1982) did find statistically significant relationships between age at menarche and number of children in the family in girls from São Luis (Maranhão state, Northeast Brazil) and Rolândia (Paraná state, South Brazil), with a later age at menarche in girls from larger families.…”

Effects of Family Context on Adolescents’ Psychological Problems: Moderated by Pubertal Timing, and Mediated by Self-Esteem and Interpersonal Relationships

“…This conceptual framework basically reflects an evolutionary-biological approach to development and has recently been supported by some animal research showing an influential link between rearing experience and sexual maturation in rats (Cameron et al 2008;Belsky 2012). This may explain a trend toward an earlier pubertal development among girls reared in urban locations where environmental stressors are more prominent than in rural areas, as shown in this study and other research in Western societies (Padez 2003;Dratva et al 2007). However, adolescents at different stages of pubertal timing did not differ in reporting scores on family context, self-esteem, and interpersonal relationships in our study where these measures were assessed concurrently at the pubertal stage.…”

Update on Age at Menarche in Italy: Toward the Leveling Off of the Secular Trend

“…Secular evolution has led to increased weight and stature during childhood [5,9,15,[17][18][19] and to a downward trend in the mean age at menarche, from about 16 to 13 years, although there have been some differences in various countries [15]. Several studies have now suggested that this trend has been slowing down during the last decade in most industrialized countries [5,15,20], but that it is still ongoing in other countries [7,8,11,21,22]. Moreover, published data have suggested that body weight and nutritional status play a role in the timing of pubertal development [23][24][25][26][27][28][29].…”