Unhealthy weight gain during pregnancy can have long-term effects on a mother's health, according to a recent study.

Researchers from Columbia University found that mothers with excessive weight gain during pregnancy weighed more and had greater body fat seven years after delivery if they began pregnancy at normal or slight overweight.

"The findings ... suggest that normal and modestly overweight women may be more physiologically sensitive to effects of high gestational weight gain and, therefore, need to be further supported to gain weight appropriately during pregnancy," researcher Elizabeth Widen said in a statement.

For the study, researchers collected and analyzed data from more than 300 African-American or Dominican mothers enrolled in the Columbia Center for Children's Environmental Health Mothers and Newborns Study in Northern Manhattan and the South Bronx from 1998 to 2013.

Before pregnancy, 5 percent of the African-American and Dominican women studied were underweight, 53 percent were normal weight, 20 percent of overweight, and 22 percent were obese. Overall, a majority of mothers (64 percent) gained more weight during pregnancy than recommended by the 2009 Institute of Medicine Guidelines, (IOM) and 38 percent were obese seven years later.

Among mothers who were not obese before pregnancy, mothers with excessive weight gain had a nearly 400 percent increased risk of obesity seven years after giving birth.

Even more striking, the effects of excessive pregnancy weight gain more markedly affected mothers with lower pre-pregnancy BMI, specifically underweight, normal weight and modest overweight. For example, for a woman with a prepregnancy BMI of 22 (normal weight), high gestational weight gain was associated with 3 percent higher body fat and 12 pounds greater weight at seven years after delivery. However, for a prepregnancy BMI of 30 (obese), excessive pregnancy weight gain was not associated with significantly higher body fat or weight at seven years.

The findings are detailed in the American Journal of Clinical Nutrition.