Postpartum weight retention is a major health concern for new mothers. The average woman can expect to retain between 0.5 and 4 kg in the first year following pregnancy, with 20% of women retaining more than 5 kg.
“[A]ppetite control deserves to be explored when developing targeted, realistic, and successful weight management interventions [for postpartum women],” says Dr. Carla Prado, Associate Professor in the Human Nutrition Research Unit at the University of Alberta.
In their new paper published in Applied Physiology, Nutrition, and Metabolism, Dr. Prado and colleagues studied the psychological, physiological, and lifestyle factors that contribute to postpartum weight retention.
Using a “motivation to eat” score that combined four different facets of appetite, they found postpartum weight retention was associated with greater appetite sensations—such as hunger—and stronger motivation to eat after eating. Interestingly, “motivation to eat” scores were also influenced by the total amount of time lactating mothers spend breastfeeding in a day.
The study, led by graduate student Leticia Pereira, recorded the prepregnancy weight of 49 women. At nine months postpartum, weight was recorded again, and appetite sensations were assessed following the consumption of a snack or meal.
Women who retained more weight nine months postpartum experienced greater sensations of hunger, lower sensations of fullness, and reported a greater motivation to eat after consuming a snack or meal.
Previous research shows that lactation and the production of breast milk are energetically demanding processes. In an attempt to identify a physiological basis for greater postpartum weight retention, Prado and colleagues explored the influence of lactation on appetite sensations.
Lactating women completed a three-day breastfeeding diary reporting the number of times they breastfed and the duration of each feeding. To estimate how much milk was produced, women were asked to weigh their infants on an electronic scale prior to and following breastfeeding.
The total amount of time spent breastfeeding in a day was positively associated with overall motivation to eat, hunger, and prospective food consumption and negatively associated with satiety and fullness. These findings suggest that the duration of lactation is a key factor that can influence daily appetite sensations and longer periods of breastfeeding may promote increased food intake.
The authors also addressed the influence of lifestyle factors such as physical fitness and general health on postpartum weight retention. Women with a higher metabolic rate and greater aerobic fitness retained significantly less weight at nine months postpartum than women with a lower metabolic rate and poorer aerobic fitness.
This comprehensive study underscores how postpartum weight retention is a multifaceted phenomenon influenced by many factors.
Prado and her co-authors expect that the findings from this research will “ultimately benefit women who have recently had children, especially those who breastfeed for long periods.”
Read the paper: Associations of appetite sensations and metabolic characteristics with weight retention in postpartum women in Applied Physiology, Nutrition, and Metabolism.