SEATTLE — A Web-based intervention that promotes physical activity and a better diet helps new mothers lose excess weight in the postpartum period, according to a randomized controlled trial.
In the trial, new mothers assigned to the intervention had about a 1.25-kg/m
“We saw a small differential effect on body mass index, not a dramatic effect, but in a fairly low-intensity intervention, we might not expect that,” lead investigator Karen J. Calfas, Ph.D., said at the meeting.
Weight gain over a person's lifespan is accelerated during certain periods, including pregnancy and the postpartum period for women, noted Dr. Calfas, who is an assistant clinical professor of family and preventive medicine at the University of California, San Diego.
“Women often don't return to their prepregnancy weight, and then maybe a second pregnancy comes and there is kind of a compounding effect of pregnancy weight over time for some women,” she said. Added to that, some women gain weight during the postpartum period because they are more sedentary and have readier access to food.
“Postpartum care is often focused really on the medical issues,” she further noted, “and the weight issues for the moms don't always get addressed.”
The investigators recruited women for the trial mainly by posting notices in community newspapers and obstetrician gynecologists' offices. To be eligible, women had to be 8 weeks to 12 months post partum and have a BMI placing them in the overweight to moderately obese category (25–35 kg/m
They were randomly assigned in nearly equal numbers to the 16-week Web-based intervention, called iMom, which encouraged increased physical activity and improved dietary intake with the goal of weight loss, or to a wait list control group.
The intervention entailed weekly Web-based educational content and behavior strategies, and monthly support phone calls. The mothers were encouraged to set goals, and they reported on their progress and received feedback online regarding weight, physical activity, and intakes of fat, fiber, and fruit and vegetables. The Web site also had a message board for connecting to other mothers.
“It's somewhat controversial to be recommending weight loss for women who might be breastfeeding,” Dr. Calfas acknowledged. However, the energy deficit recommended in the intervention was carefully tailored according to whether women were breastfeeding and how much. “The research shows that if calories are reduced slightly and weight is lost slowly over time, that it does not affect either the quantity or the quality of breast milk that is produced,” she noted.
Study results showed that mothers assigned to the intervention lost about 1.5 kg (3.3 lb) on average, whereas those assigned to the wait list lost about 0.5 kg (1.1 lb). The difference corresponded to a 1.21-kg (2.67-lb) greater loss for the former group. Similarly, BMI fell by about 1.25 kg/m
“The women, anecdotally, reported high satisfaction with [the intervention], and they especially appreciated the fact that they could do it whenever it was convenient for them,” commented Dr. Calfas.
Ongoing analyses will be looking for any dose-response relationship, evaluating how much the new mothers actually used the Web site, she said, noting that overall use was not as high as hoped.
Dr. Calfas is cofounder of and stockholder in Santech Inc., a company that uses mobile and Web technologies to promote behavior change.