Mind your weight before you conceive second time

Increase in weight between first and second pregnancy can lead to pregnancy complications, reveals a new study.

The study conducted at the Harvard School of Public Health in Boston and the Karolinska Institutet in Stockholm, Sweden found an association between obesity and pregnancy complications.

The researchers, Eduardo Villamor, Assistant Professor of International Nutrition at HSPH and Sven Cnattingius, Professor of Epidemiology at Karolinska Institutet found that the risk of adverse outcomes increased even in women who were not overweight, but who gained a modest amount of weight between pregnancies.

The adverse outcomes during the second pregnancy included maternal complications, such as pre-eclampsia, gestational diabetes, gestational hypertension and caesarean delivery, and perinatal complications, such as stillbirth and large-for-gestational-age birth.

The study looked into medical records of more than 150,000 women who had their first and second children between 1992 and 2001.

BMI was calculated for each woman (BMI is the weight in kilograms divided by height in meter, squared). A BMI of 20-25 is considered healthy while BMI from 25-30 is considered overweight and from 30-40 is considered obese.

The BMI at the first prenatal visit of each pregnancy was calculated. Then the difference between BMI at the beginning of the first and second pregnancies was calculated.

The results revealed that a women with a weight gain of one to two BMI units (one BMI unit is 3Kg or 6.6 pounds) were 20 to 40 percent more likely to suffer from diabetes and high blood pressure.

Whereas, a BMI increase of three or more units showed a 63 percent higher chances of stillbirth compared to a gain of less than one BMI unit and also a greater effect on all other complications.

The researchers also highlighted the increased risk of complications in women who were not overweight, but who gained a modest amount of weight between pregnancies.

“A few kilos, even among women who are not overweight, can make all the difference”, warned the researchers.

The limiting factor of the study was that, it was difficult to differentiate whether the weight gain between pregnancies was due to lack of weight loss after the first pregnancy or due to excessive weight gain during the initial pregnancy. Also, possibility of other ailments associated with weight gain and adverse pregnancy outcomes could not be ruled out.