Eating behavior and pregnancy outcome

Abstract

The association between clinical eating disorders, maternal body weight, shape, and eating concerns, and the birth of low-birth-weight infants (LBW; less than 2500 g) was investigated using a retrospective case–control study. Eighty-eight women delivering LBW infants were interviewed and then divided into two groups—those delivering term, small-for-gestational-age infants (SGA; 37 or more completed weeks, n=34) and those delivering premature infants (less than 37 completed weeks, n=54). There were 86 reference women (CTRL) matched for age, parity, and health insurance status, who delivered babies with birth weights greater than 2500 g. In the week postpartum, women delivering term SGA, premature (PREM), and CTRL infants were interviewed using a semistructured interview. One section of this interview included a modified version of the Eating Disorder Examination (EDE), which retrospectively generated, over the previous 12 months, diagnosis of an eating disorder and maternal “normative” weight and shape concerns. In the 3 months before pregnancy, 32% of SGA women, 9% PREM women, and 5% of reference women were diagnosed as having a clinical eating disorder. Women with a past history of an eating disorder had no greater risk of delivering a low-birth-weight infant. Women delivering SGA infants reported elevated eating disorder psychopathology postdelivery (Eating Disorders Inventory, EDI) and more disturbances in eating behavior before and during pregnancy. Unique predictors for delivery of a LBW term SGA infant were: low maternal prepregnancy body weight, smoking, low maternal weekly weight gain, and elevated EDI (Bulimia subscale). Unique predictors for delivery of a LBW premature infant were: lower maternal occupational status, vomiting in pregnancy, and lower dietary restraint. Women with disordered eating were shown to be at greater risk of delivering term SGA infants. Predictors of term growth retardation are partly determined by maternal behavior.

Introduction

Pregnancy poses a significant challenge to women concerned with their weight and shape. Pregnancy has the potential to raise issues central in the psychology of eating disorders including “fear of pregnancy and motherhood for their negative consequences ranging from loss of control over one's body to loss of control over one's life” [1]. Research into the “normative” weight concerns of pregnant women by Fairburn and Welch [2] has shown that 40% of UK primigravidae women fear weight gain in pregnancy and 72% fear that they will be unable to return to their prepregnancy weight. Other research in Australia has shown that women reporting “disordered eating” in pregnancy (24%) were at heightened risk of antenatal complications and delivery of a LBW infant [3]. Other studies have shown that nutrient intake during pregnancy has been linked directly [4], and indirectly [5], to the chance of delivering a LBW baby.

The potential for pregnancy to exert a positive or negative influence on eating disorder symptoms is inconclusive. Some studies reported a decline [6], and others a heightened [7] symptomatology. This study was initiated to clarify this issue.

Research has emphasized the importance of identifying determinants of birth weight, particularly that below 2500 g, which carries heightened risk of infant mortality and later childhood morbidity [8]. Anorexia nervosa (AN) and bulimia nervosa (BN) patients who are symptomatic during pregnancy are likely to gain significantly less weight and risk delivering a LBW infant 6, 7, 9, 10. Factors predicting delivery of a LBW baby that are associated with maternal eating disorders and disordered eating have not been studied.

The aim of this unique study is to investigate the factors associated with clinical eating disorders and “normative” weight and shape concerns and disturbances in eating behavior that predict delivery of LBW infants as a result of term growth retardation or prematurity.