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Maternal Depletion (maternal + depletion)

Distribution by Scientific Domains
Life Sciences100%

Selected Abstracts

Independent changes in female body shape with parity and age: A life-history approach to female adiposity

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2010
Jonathan C.K. Wells
Both aging and reproduction have been shown to influence female body shape in industrialized populations, involving redistribution of fat from lower to upper body regions. However, the extent to which effects of parity vary by age and the extent to which age affects shape independent of parity remain unclear. We studied shape variability in relation to age and parity in a cross-sectional survey of 4,130 white British women, using three-dimensional photonic scanning. In women ,40 years, bearing children was associated with increased abdominal and reduced thigh girths, independent of age and BMI. Very few such differences were statistically significant in women >40 years, suggesting the effects of parity on shape wash out over time. In nulliparous women, aging was associated with shape variability, independent of BMI, with a similar pattern of associations evident in women both ,40 and >40 years. Our data support previous findings of "covert maternal depletion" in relation to parity, but show that this is merely a more pronounced component of a general strategic shift of fat from lower to upper body with age. These findings are consistent with a life-history model of female energy stores being allocated to competing "reproduction" and "maintenance" depots, with the optimal trade-off strategy changing with age and with that strategic shift accelerated by bearing children. This model is relevant to the "grandmother hypothesis." The dual effects of age and parity on fat distribution substantially resolve by old age the profound sexual dimorphism in adiposity present at the start of adult life. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source]

Fertility, body size, and shape: An empirical test of the covert maternal depletion hypothesis,

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2009
Ilona Nenko
In populations with limited resources, high-reproductive effort may lead to poor nutritional status of the mother (the maternal depletion syndrome), whereas in well-nourished populations woman's body weight tends to increase after each pregnancy. However, in affluent populations, women's body shape may change due to mobilization of polyunsaturated fatty acids (PUFAs) from the lower parts of their bodies to meet the needs of the developing child (the "covert maternal depletion"). We studied relationships between reproductive history traits and body size and shape for 296 rural, parous women in good nutritional status (mean body mass index, BMI = 27.9, SD = 5.94), aged 22,85 (mean 47.8, SD = 16.34) from southern Poland. Body mass adjusted for age, age of menarche, body height, and similarly adjusted BMI were each positively related to the number of children born by a woman (R = 0.13, P = 0.02 and R = 0.13, P = 0.02, respectively). Waist and hip circumferences, adjusted for confounders, did not show statistically significant relationships with the number of children. Moreover, groups with low and high parity did not significantly differ in hip/BMI and waist/BMI ratios, which were proposed to be indicators of covert form of maternal depletion (after controlling for overall body fatness and age). In conclusion, parity caused a slightly higher body mass and BMI later in life. However, parity did not lead to covert maternal depletion, perhaps because women in this population have relatively high-dietary intake of PUFAs. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source]

Demographic consequences of unpredictability in fertility outcomes

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2002
Paul Leslie
Child survival is probabilistic, but the unpredictability in family formation and completed family size has been neglected in the fertility literature. In many societies, ending the family cycle with too few or too many surviving offspring entails serious social, economic, or fitness consequences. A model of risk- (or variance-) sensitive adaptive behavior that addresses long-term fertility outcomes is presented. The model shows that under conditions likely to be common, optimal, risk-sensitive reproductive strategies deviate systematically from the completed family size that would be expected if reproductive outcome is were predictable. This is termed the "variance compensation hypothesis." Variance compensation may be either positive or negative, resulting in augmented or diminished fertility. Which outcome obtained is a function of identifiable social, economic, and environmental factors. Through its effect on fertility behavior, variance compensation has a direct bearing on birth spacing and completed fertility, and thereby on problems in demography and human population biology ranging from demographic transitions to maternal depletion and child health. Risk-sensitive models will be a necessary component of a general theory of fertility. Am. J. Hum. Biol. 14:168,183, 2002. © 2002 Wiley-Liss, Inc. [source]

Changes in body fat distribution in relation to parity in American women: A covert form of maternal depletion

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2006
William D. Lassek
Abstract Using data from the Third National Health and Nutrition Examination Survey (NHANES III), conducted from 1988,1994, we investigated the effect of reproduction on the distribution of body fat in well-nourished American women. While women tend to gain weight and fat with succeeding pregnancies, if age and body mass index are controlled, increasing parity is associated with a decrease in hip and thigh circumferences, suprailiac and thigh skinfolds, and body fat estimated from skinfolds, while waist circumference increases, resulting in a relative decrease in lower-body fat. The mobilization of fat stores in the lower body during late pregnancy and lactation may help to meet the special needs of the developing brain for essential fatty acids and energy during the time of peak growth. When fat is regained after the postpartum period, relatively more is stored in central vs. peripheral depots, resulting in a patterned change in body shape with parity. Am J Phys Anthropol 131:295,302, 2006. © 2006 Wiley-Liss, Inc. [source]