Based on its review of the evidence, the task force recommended that clinicians offer pregnant patients recurring behavioral counseling interventions aimed at promoting healthy weight and preventing excess gestational weight gain in pregnancy. This is a “B” recommendation.
This is the first time the task force has reviewed evidence on how to help pregnant patients maintain a healthy weight. “The good news is that recurring counseling is effective and can be incorporated into existing prenatal care,” task force member Melissa Simon, M.D., M.P.H., said in a press release.
Weight maintenance and weight gain are important considerations in people who are pregnant and those of childbearing age. While weight gain is expected during pregnancy, the CDC estimates that only about one-third of people gain the recommended amount of weight while pregnant, while about one-fifth gain too little weight and almost half gain too much. Additionally, evidence suggests that excessive gestational weight gain can cause a number of complications, including some hypertensive disorders and increased cesarean birth rates.
To determine the effects of counseling and active behavioral interventions on healthy weight and weight gain during pregnancy, the task force commissioned a systematic evidence review. The review consisted of 68 trials extracted from the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews and the Medline database, with additional surveillance of the evidence conducted through Aug. 31, 2020.
Based on the review, investigators found that both counseling-only and active gestational weight gain interventions were associated with small but statistically significant risk reductions for two maternal health outcomes (gestational diabetes and emergency cesarean delivery).
Compared with controls, however, there was no association between gestational weight gain interventions with regard to other outcomes, such as gestational hypertension, risk of cesarean delivery, preeclampsia, postpartum hemorrhage and perineal trauma.
For infant health outcomes, gestational weight gain interventions were associated with decreased risk of infant macrosomia and large for gestational age (defined as birth weight above the 90th percentile for gestational age), but were not associated with risk of preterm birth, respiratory distress syndrome, shoulder dystocia or neonatal ICU admission.
Across all prepregnancy weight categories, gestational weight interventions were associated with modest (1.02 kilograms) reductions in weight gain versus controls. High-intensity interventions that consisted of 12 or more sessions were associated with greater effects than moderate- or low-intensity interventions, and the effects were greater in patients categorized as obese or overweight compared with those with a normal prepregnancy body mass index.
Interventions also were associated with a reduced likelihood of gaining gestational weight gain in excess of Institute of Medicine recommendations, with active and high-intensity interventions producing greater effects.
The task force found that while many studies examined the effects of interventions on gestational weight gain, data on their effects on maternal and infant health outcomes was more limited. They recommended that future trials evaluate more intensive behavioral interventions, and asked for more studies that would determine the optimal frequency, length of sessions and number of sessions necessary for an intervention to provide additional evidence on effectiveness.
The task force also called for more research to determine the effectiveness of interventions to limit gestational weight gain in specific populations of pregnant people, including those of advanced maternal age, adolescents and those in priority populations as defined by race, ethnicity or socioeconomic status.
Scott Hartman, M.D., chair of the Academy’s Commission on Health of the Public and Science and an associate professor of clinical family medicine and maternity care coordinator for the primary care network at the University of Rochester Medical Center in Rochester, N.Y., told AAFP News that while the findings didn’t surprise him, he appreciated the task force’s work on the topic.
“It’s great to have such an extensive analysis at hand to sort of ‘validate’ what most clinicians generally think: that behavioral interventions matter, in pregnancy or otherwise,” Hartman said. “We’ve found this to be true for smoking and so many other health behaviors, so it makes sense that it would matter in pregnancy.”
“The take-home message here is that nutritional counseling and active behavioral interventions do matter and can really make a difference in achieving healthy weight gain in pregnancy,” Hartman added.
Hartman said that in his own practice, he offers referrals to nutritionists for all patients who present for preconception or maternity care and emphasizes referrals to those with other risk factors such as a high BMI, pre-existing diabetes or other chronic medical conditions.
Hartman also noted that the task force’s finding that more intensive forms of counseling demonstrated greater effectiveness than low- or moderate-intensity interventions could modify the way some FPs care for pregnant patients.
“I’ve always been a big believer in the work of dietitians, nutritionists and nurse care managers,” Hartman said. “This USPSTF statement serves for me as verification that these kinds of referrals should really be utilized, given that the most effective interventions are probably more than a family physician could provide in a typical prenatal visit.”
To account for the holidays, the task force has extended its public comment period from four weeks to five weeks. As such, the USPSTF is accepting comments on the draft recommendation statement and draft evidence review on behavioral counseling interventions to promote healthy weight and weight gain during pregnancy until 11:59 p.m. ET on Jan. 11, 2021. All comments received will be considered as the task force prepares its final recommendation.
The AAFP will review the USPSTF’s draft recommendation statement and supporting evidence and will provide comments to the task force. The Academy will release its own recommendation on the topic after the task force finalizes its guidance.