Pregnant woman's diet may 'affect birthweight of daughter's future children'

The study conducted on 3,000 women in the Philippines found that what women ate during their pregnancies could influence the size of their grandchildren

A woman’s diet during pregnancy may affect the birthweight of her daughter’s children a generation later, a study of 3,000 women in the Philippines has found.

Researchers discovered that the nutrition of a grandmother during her pregnancy can affect the size of her grandchildren at birth by influencing her daughter’s own physiology throughout her life.

Christopher Kuzawa of Northwester University in Chicago said that the results of the on-going study which began in the 1980s suggest that a mother’s nutrition while she was in the womb herself and during her infancy may play a greater role in the birth weight of her babies than what she eats as an adult or during pregnancy.

“Our findings add to the growing evidence that a baby’s birthweight is linked to the nutrition that her mother experienced as an infant or young child,” Dr Kuzawa told the American Association for the Advancement of Science.

"[There is] quite a bit of converging evidence that the quantity of calories you consume during pregnancy does not have a big effect on the baby. It is more about pre-pregnancy nutrition and nutrition during early development," Dr Kuzawa said.

“The mother’s infancy nutrition and the grandmother’s pregnancy nutrition both predicted birth weight in offspring of the mothers,” he told the meeting. 

Although scientists have known for some time about the influence of a mother’s nutrition during her development on her own children’s birthweights, this is one of the first studies to suggest that a grandmother’s diet during pregnancy may also play a role.

Dr Kuzawa emphasised that the findings were still preliminary and that they relied on mothers at the age of between 21 and 22 remembering their own birthweights and dietary intakes when they were children. 

The population under study in the Philippines may also have experienced greater malnourishment in the previous two generations than women in more developed nations such as Britain.

“There is an old idea that goes back a few decades that the nutrition that a mother experienced when she was in utero has an intergenerational effect – influencing the nutrition that she provides to her own baby decades later,” he said.

“One possibility is that the nutrition that a female foetus experiences while in utero has an intergenerational effect, influencing in utero growth in her future offspring,” he told the meeting.

Mothers should be relaxed about their diet during pregnancy so long as it is balanced and healthy, he said. 

“The mother’s body seems to do a good job of buffering overall nutritional supply to her growing baby. Within the bounds of a healthy balanced diet, the overall quantity of food that a mother eats is unlikely to have large effects on her baby’s birth weight,” Dr Kuzawa said.

"It's going to turn out the weight it's going to turn out whatever your specific dietary choices."