According to a recent review published in JAMA Network Open, interventions in routine antenatal care may need further research before being implemented.
Overweight or obesity has been reported in about 70% of female adults in the United States, and pregnancy has been associated with severe overweight and obesity risk. Recommendations for gestational weight gain (GWG) are passed by about half of pregnant individuals, increasing the risks of adverse maternal and neonatal outcomes.
Lifestyle interventions for managing GWG have been suggested as a public health strategy for preventing excessive maternal weight gain. However, data evaluating the efficacy of interventions is limited.
In 2022, investigators conducted a systematic review evaluating 117 randomized clinical trials (RCTs) on antenatal lifestyle interventions for decreasing GWG. To determine components of these interventions associated with decreased GWG, investigators conducted a secondary analysis of the 2022 review.
In the original review, the Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, MEDLINE, Health Technology Assessment Database, and Embase databases were consulted for RTCs on antenatal lifestyle interventions. Studies up to May 6, 2020, were included in the analysis.
Lifestyle interventions evaluated included physical activity, antenatal diet, and mixed interventions. Studies needed to report a mean GWG per group to be included. Exclusion criteria included analyzing non-lifestyle interventions, including patients with multiple pregnancies or pre-existing conditions, and being published before 1990.
Two independent reviewers performed extraction of general study characteristics. These included country, author, year of publication, mean body mass index (BMI) of the study population, and mean GWG.
Interventions using specified dietary targets were considered dietary interventions, while interventions taking place in controlled conditions or those structured but self-led were considered physical activity interventions. Interventions which did not match either of these criteria were considered mixed interventions.
Characteristics of interventions evaluated included framework, resources, facilitators, training for facilitators, format, setting, number and duration of settings, gestational age at commencement, intervention duration in weeks, tailoring, completion, and adherence and attrition.
There were 99 studies included in the secondary analysis, including 34,546 pregnant individuals with a mean BMI of 20.6 to 38.6. Most interventions were conducted face-to-face with groups. Of studies, 67.7% did not train facilitators.
Significant variations in GWG outcomes were found based on the type of intervention facilitator. The most efficacious facilitator type was allied health staff, while no facilitator was the least efficacious.
Of studies, 67.7% were delivered in early pregnancy, 68.7% were in a clinical setting, and 40.4% had a high number of sessions. An association between these factors and GWG was not determined.
When evaluating dietary interventions, 69.2% were reported as being delivered face-to-face, 53.8% had a low number of sessions, and moderate intervention and high intervention duration were both seen in 30.8%. A greater reduction in GWG was observed in interventions with a moderate number of visits, but other factors did not show a significant impact on GWG.
Allied health staff delivered 81.3% of diet with physical activity interventions, with a majority being in an individual format and face-to-face. A low number of sessions was seen in 43.7% of studies, and a moderate number in 31.2%. Intervention duration was also often low or moderate. Factors evaluated were not associated with GWG reduction.
A group format was reported for 83.3% of physical activity interventions. Most were delivered by allied health staff and while face-to-face. Of studies, 83.3% had a high number of sessions and 81% had a moderate length. Intervention factors were not associated with GWG.
Of mixed interventions, 82.1% were individual, 67.9% face-to-face, 60.7% with a low number of sessions, and 52.6% with moderate duration. Adherence was not reported in 71.4% of studies, but improved efficacy was found in studies with high adherence. No other factors were significantly associated with GWG.
Overall, no conclusive associations were found between interventions and GWG. Investigators recommended future studies evaluate components of intervention which may inform implementations.
Reference
Harrison CL, Bahri Khomami M, Enticott J, Thangaratinam S, Rogozińska E, Teede HJ. Key Components of Antenatal Lifestyle Interventions to Optimize Gestational Weight Gain: Secondary Analysis of a Systematic Review. JAMA Netw Open. 2023;6(6):e2318031. doi:10.1001/jamanetworkopen.2023.18031