Infants of Mothers with Eating Disorders

An infant’s early feeding pattern has immediate and long-term effects upon his or her growth, and long-lasting effects on well-being. Maternal eating disorders also affect infant feeding and growth in the first year of life. Results of two recent studies have demonstrated the importance of monitoring early feeding patterns for potential effects on growth and risk of childhood obesity.

Infants of mothers with eating disorders

Most studies of mothers with eating disorders show that the mothers tend to have difficulties feeding their infants, including the infant’s refusal of solid foods, more unscheduled feedings, and other problems. Most studies of these infants have shown shorter duration of breast-feeding, faster suckling, and lower weight.

Drs. Nadia Micali, Emily Simonoff, and Janet Treasure used data from 12,050 women and their infants, who were participating in the Avon Longitudinal Study of Parents and Children, to examine feeding difficulties at 6 months of age and 1 year. They particularly examined breast-feeding during the first year, and weight and conditional growth at 9 months (J Pediatr 2009; 154:55). (Conditional growth is a method of comparing an infant’s previous weight with his or her current growth, rather than using a standardized age-weight chart. This method allows researchers to more closely watch an infant’s growth.) They then compared these data with those of infants of women with a self-reported history of anorexia nervosa (AN) or bulimia nervosa (BN) and two control groups of women with and without psychiatric disorders.

What the researchers found

Women with a history of eating disorders were more likely to start breast-feeding their infants than were those in the other groups, and were less likely to stop breast-feeding during the first year of their infant’s life compared with the control women. Women with BN were most likely to continue breast-feeding. In contrast, women with other psychiatric disorders were more likely to stop breast feeding than were the healthy controls.

Feeding difficulties were relatively common across all groups during the infant’s first year of life. Mothers with AN reported more early-onset and persistent feeding difficulties, except refusal to take solid foods, compared with controls, but this pattern was comparable to that seen among mothers with other psychiatric disorders.  In contrast, infants of women with BN differed from those of controls in the rate of refusal to take solids and from those of women with AN in the rate of being unsatisfied or hungry after feeding.

Feeding difficulties were relatively
common across all groups during
the infant’s first year of life.

All the feeding difficulties assessed at 1 month and at 6 months of age persisted, but no established feeding routine affected weight z-scores at 9 months. Slower-than-normal feeding, eating only a small amount of food, and refusal to eat solids were positively related to low weight and negatively associated with higher weight. A maternal history of BN was predictive of the infant being overweight in univariate analyses.

Infants of mothers with BN were heavier and grew more rapidly between birth and 9 months compared to infants born to control women and to women with other psychiatric disorders. Possible explanations for these patterns, according to the authors, are that these infants are genetically at risk for higher weight or that these women overeat during pregnancy, affecting their infants’ appetite regulation. A third possibility is that a mother exerting greater control during feeding predicts greater infant weight gain in the infant’s first year of life. 

An interesting finding was that although women with AN reported high rates of their infants “not being satisfied” or “hungry” after feeding (which would have predicted overweight by 9 months) did not have overweight infants at 9 months. Although women with other psychiatric disorders reported a high rate of feeding difficulties, this was not reflected in poor growth or low weight among their infants.

‘Ballooning’ babies may be at increased risk of obesity

Harvard Medical School researchers recently reported that infants who “balloon up, ” or gain a lot of weight during the first 6 months of life, may be at increased risk for childhood obesity. Elsie Taveras, MD, MPH and her colleagues examined a subset of 559 children in Project Viva, an ongoing prospective cohort study of pregnant women and their children (Pediatrics 2009; 123:1177). The researchers measured the infants’ length and weight at birth, at 6 months, and again at 3 years. By 3 years of age, 9% of children were obese, and this was tied to rapid increases in weight for length during the first 6 months of life. Each increment in weight-for-length z-scores at 6 months was associated with higher odds of obesity by age 3.