Environmental factors influencing growth and pubertal development.

Abstract

Postnatal growth is based on hereditary signals and environmental factors in a complex regulatory network. Each factor must be in an optimal state for normal growth of the child. Fetal conditions may also have consequences on postnatal height. Intrauterine growth retardation can be recovered postnatally, although postnatal growth remains depressed in about one-third of cases. After birth, the environment may exert either a positive or negative effect on growth. In underdeveloped countries, malnutrition plays a major role in inhibiting the growth process. Children from families of higher socioeconomic classes are taller than their coevals in the lower socioeconomic groups. Urbanization also has a positive effect on growth. Better child care is supported by sufficient food supply, appropriate health and sanitation services, and a higher level of education. Over the last century, these factors have induced a taller stature and a more rapid maturity in Europe, North America, and Australia; a phenomenon which has been referred to as "the secular trend" in growth. Recently, a secular trend has also been reported in some developing countries. Although urbanization in general appears to be associated with better conditions of living, this is not the case in the slums of South America or in Africa where rural children are better off than children living in the poor cities. This paper describes in more detail the different hereditary and environmental factors that act during the fetal period and postnatally, and which play a role in human growth and pubertal development.

Global Developmental Delay and Its Determinants Among Urban Infants and Toddlers: A Cross Sectional Study

“…Chronic undernutrition manifest in the form of stunting was observed in as many as 59% of children. Several other studies have also shown that stunted growth adversely affects a child's cognitive ability later in childhood [19][20][21].…”

Serum Hormones in Boys Prenatally Exposed to Polychlorinated Biphenyls and Dibenzofurans

“…Animal studies suggested that prenatal exposure to endocrine disruptors might produce adverse effects on male pubertal development via the changes of sex hormone levels (Wood et al, 1991;Delemarre-van de Waal, 1993;Howdeshell et al, 1999). The effects of an imbalance between estrogen and androgen may induce developmental abnormalities, such as hypospadia and cryptorchidism, oligospermia, and testicular cancer (Jensen et al, 1995;Toppari et al, 1996;Jorgensen et al, 1999).…”

Effect of Community of Residence on Neurobehavioral Development in Infants and Young Children in a Flower-Growing Region of Ecuador

“…Research shows that chronic malnutrition (i.e., stunting) is associated with delayed neurobehavioral development (Delemarre-van de Waal 1993; Winick 1971), specifically with lowered gross and fine motor skills (Benefice et al 1996; Cheung et al 2001). In our study, a high percentage of stunting was observed.…”