Mothers who gain weight face risks in pregnancy

Mothers who gain weight after their first baby risk serious complications when they get pregnant again, a study has shown.

Researchers who looked at more than 150,000 Swedish women found weight gain between pregnancies was strongly associated with major problems. Even women who were not technically overweight but who put on pounds after their first birth were at risk.

The findings were based on body mass index (BMI) readings taken of the women at the beginning of their first and second pregnancies. BMI is a measurement that relates height and weight and is often used by health professionals. A BMI of under 18.5 is classified as underweight, 18.5 to 24.9 as normal, 25 to 29.9 as overweight, and 30 or above as obese, informs Independent.

According to Life Style Extra, nutritionist Dr Eduardo Villamor and epidemiologist Professor Sven Cnattingius, whose findings are published in The Lancet, said: "Our results strengthen the argument for a causal relationship between maternal overweight or obesity and adverse pregnancy outcomes.

"Additionally they suggest modest increases in BMI before pregnancy could result in perinatal complications, even if a woman does not become overweight."

Dr Villamor, of the Harvard School of Public Health, Boston, and Prof Cnattingius, of the Karolinska Institute, Stockholm, added: "The results provide robust epidemiological evidence for advocating weight loss in overweight and obese women who are planning to become pregnant, and to prevent weight gain in the larger population of women with healthy weight."

Not only did the researchers find that an increase in body mass index was associated with adverse outcomes, they also showed "a dose response effect".