Babies born to women who had gastric bypass surgery at risk for nutritional deficits

A study from Ambroise Pare University Hospital in Boulogne Billancourt, France, suggests that infants born to women who’ve undergone weight loss surgery for type 2 diabetes or obesity reversal are more likely to have nutritional deficiencies at birth.
The research, presented during the European Society for Paediatric Endocrinology (ESPE) annual meeting, show that babies delivered after maternal Roux-en-Y gastric bypass tend to be small for their gestational age and suffer nutritional deficits despite supplementation during pregnancy.
Researchers knew that there are nutrient deficiencies because of malabsorption in women who’ve undergone bariatric surgery, but this is the first study showing that infants born to these women are exposed to the same risk.
Gastric bypass is a radical surgery where the stomach is cut apart and the top portion is used to make a much smaller stomach. The pouch is then connected directly to the middle of the small intestine, bypassing the duodenum, to help people lose weight faster.
The duodenum is responsible for releasing enzymes that help to break down fats. In bypassing the duodenum, this process is interrupted and a resulting problem is that many essential vitamins, which are fat-soluble, including vitamin A, B12, D, E and K, aren’t absorbed.
So post-operative patients who are not absorbing fat correctly are also not absorbing and using those vitamins, even if they use supplements.
Some of these vitamins that can’t be absorbed are also needed to assist the absorption of minerals like calcium, which can lead to a decrease in bone mass.
Previous research has found that the incidence of vitamin A deficiency among gastric bypass patients can be as high as 69 per cent, vitamin K deficiency 68 per cent, and vitamin D deficiency 63 per cent by the fourth year following the surgery. The incidence of hypocalcemia (low calcium levels) increased from 15 per cent to 48 per cent over the same period of time too.
The current study followed 56 women who gave birth 32 months after a Roux-en-Y gastric bypass and who took daily multivitamin supplements throughout their pregnancy. They were matched with 56 healthy control participants who conceived over the same period.
At the time of delivery, the researchers sampled both maternal blood and cord blood from the infants to check nutrient levels, and compared the infant growth between the two groups.
They found that 23 per cent of infants born to the bariatric-surgery group were small for their gestational age, while this only happened for 3.6 per cent of infants born to controls.
Bariatric-surgery infants were also significantly more likely to be deficient in calcium (2.55 mmol/L vs 2.63 mmol/L), zinc (0.85 mg/L vs 1.36 mg/L), and vitamin A (1.85 µg/L vs 2.26 µg/L) than control infants.
Dr Maxime Gerard, who led the study, said the restriction in growth is a marker of malabsorption of nutrients by their mothers.
It is not to say that obese women who wish to get pregnant shouldn’t consider a bariatric surgery procedure. But, researchers believe other types of bariatric surgery than Roux-en-Y, such as gastric banding and sleeve gastrectomy, are less likely to cause malabsorption of nutrients.