Failure of a nursing infant to thrive after the mother's gastric bypass for morbid obesity

A case is described of a breast-fed, four-month-old infant who had gained only two pounds (lb) and 11 ounces (oz) since birth, constituting a case of 'failure to thrive'. The mother had previously undergone gastric bypass surgery to manage her extreme obesity. She had remained stable at a body weight that was 15 percent above the ideal body weight for her height for four months before becoming pregnant with this baby. Although the mother consumed a diet including fish and chicken (good sources of protein) during her pregnancy, she did not comply with instructions to take multivitamins and iron, and was anemic during the entire pregnancy. The mother was not given vitamin B-12 injections, even though this is recommended following gastric bypass surgery. She gained 14 lb during the pregnancy and delivered a 19-inch infant girl weighing 5 lb and 14 oz. The newborn had a normal physical condition, as indicated by her Apgar scores, but was jittery and hypoglycemic (had abnormally low blood sugar levels). The infant then had very poor growth for the first four months of her life (while being breast-fed), and the mother was instructed to introduce formula supplements into the infant's feeding regimen. When the baby's growth improved over the next two months, the mother stopped breast-feeding and switched the baby to formula. The mother's breast milk was shown to have a fat content that was only 39 percent of the normal level, and the milk was considerably less rich in energy than normal breast milk. Studies show that gastric bypass may adversely affect the absorption of fats. In this case, malabsorption of fats by the mother may have altered the fat content of her breast milk. Hence, mothers who have undergone gastric bypass and intend to breast-feed must be monitored for the energy content of their breast milk, and should also be made aware of the critical importance of complying with medical instructions. (Consumer Summary produced by Reliance Medical Information, Inc.)