Pregnant women who gain a lot of weight in the early stages of their pregnancy are significantly more likely to go on to have bigger babies with more body fat, a new study has found.

There are a number of health risks associated with having a big baby for both the mother and child. The mother may experience issues such as tearing while giving birth and has a higher risk of having to undergo a caesarean section.

The baby meanwhile may experience shoulder dystocia during birth, which is when the shoulders get stuck after the head has already been pushed out. This is rare but serious. It can lead to nerve damage in the baby's arm or shoulder, or even a broken collar bone.

Canadian researchers followed the progress of 172 pregnant women between 1995 and 2011. All were considered healthy and none smoked.

The participants had access to healthy eating guidelines and were encouraged to undertake basic aerobic exercises three to four times a week.

The study found that just over half (52%) of the women gained excessive weight while pregnant. However, those who gained excessive weight during the first half of their pregnancy were almost three times more likely to give birth to bigger babies with excessive body fat - that is more than 14%.

According to lead researcher, Assistant Prof Margie Davenport, of the University of Alberta, a healthy lifestyle during pregnancy has long-term repercussions for both the mother and child.

"Infants who are larger at birth tend to become larger children, and that creates a risk for developing into obese and overweight children and adults," she explained.

The researchers pointed out that one of the biggest challenges for healthcare professionals in relation to pregnant women is the myth that they should be ‘eating for two'.

"For many mothers, eating for two is taken too literally. People feel like they've been given an allowance to eat whatever they want, and that can lead to weight gain," they noted.

Details of these findings are published in the journal, Obstetrics & Gynecology.

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