Coombe study finds 10lb weight increase by second pregnancy

Two-thirds of first-time mothers had gained 10lb when they booked antenatal care for a second pregnancy, according to a longitudinal study carried out in the Coombe Hospital, Dublin.

The study, Interpregnancy Changes in Maternal Weight and Body Mass, was published in this month’s American Journal of Perinatology and was carried out from 2009 to 2012. Some 1,220 women returned with a second pregnancy within the timeframe and so qualified for the research.

Two-thirds of first-time mothers gained an average of 10.1 lb when they booked for antenatal care a second time. As a result, 20.2 per cent were now in a higher BMI category and 4.8 per cent had become obese.

The authors say maternal obesity is associated with an increase in pregnancy complications and an increase in obstetric interventions.

“These findings have implications for a woman’s future obstetric and medical wellbeing,” they say. “This increase in maternal weight and, thus, BMI in the majority of women after the birth of their first child, is of concern clinically.

“A large Swedish epidemiological study of 151,080 women found that, on average, women gained over half a BMI unit during a mean interpregnancy interval of 24 months between first and second pregnancies. Interpregnancy weight gain was strongly associated with an increased risk of maternal and perinatal complications independently of whether the woman was overweight or not.

“Little attention has been paid to the chances of becoming overweight or obese after a first child. The development of obesity with parenthood may have consequences not only for future pregnancies and deliveries but also lifelong consequences for the woman herself.”

The authors say further studies are required to identify if changes in maternal diet and/or physical activity were responsible for these weight changes after the birth of a first child. “If there are lifestyle differences, the advice women get about healthy eating and physical activity before and during pregnancy may need to be reinforced after delivery.”