Timing of Complementary Feeding in Preterm Infants and Prevalence of Overweight and Obesity
Authors: Karin M. Vissers, Edith J. M. Feskens, Johannes B. van Goudoever, Arieke J. Janse, Martin G.A. Baartmans, Ron H.T. van Beek, Frans B. Plotz, Marianne Eijkermans, Angelique K.E. Hoffmann-Haringsma, Jeroen H.L van Hoorn, Christine H. ten Hove, Monique A.M. Jacobs, Jorien M. Kerstjens, Henriette van Laerhoven, Jeannette S. von Lindern, Dianne A.P.G.F. Maingay-Visser, Clemens B. Meijssen, Rob M.J. Moonen, Annemarie J.H. Oudshoorn, Linda G.M. van Rooij, Sophie R.D. van der Schoor
Journal: JAMA Network Open (2025)

Importance The appropriate time for initiating complementary feeding in preterm infants is crucial for optimizing growth and preventing long-term health issues, such as overweight. Currently, there are no established guidelines for preterm infants. Objective To investigate the effect of initiating complementary feeding at corrected age 12 weeks vs 17 weeks on the prevalence of overweight and obesity at corrected age 2 years in preterm infants. Design, Setting, and Participants This multicenter randomized clinical trial was conducted between May 13, 2016, and April 26, 2021, with follow-up completed in December 2023. Seventeen hospitals in the Netherlands recruited preterm infants born between gestational age (GA) 30 and 36 weeks, supplemented with a reference group of full-term infants. Intervention Preterm infants were randomized to initiating complementary feeding at corrected age 12 weeks (early group) or 17 weeks (late group). Main Outcomes and Measures The primary outcome was the prevalence of overweight and obesity at corrected age 2 years measured using logistic mixed models. Secondary outcomes were height, weight, head circumference, body mass index, and z scores at corrected age 1 and 2 years, as well as neurodevelopment, atopic dermatitis score, and health-related quality of life. Results A total of 255 preterm infants were included and randomly assigned, with 131 (51.4%; median [IQR] GA, 34 weeks 2 days [32 weeks 5 days to 35 weeks 1 day]; 77 male [58.8%]) allocated to the early group and 124 (48.6%; median [IQR] GA, 34 weeks 0 days [32 weeks 6 days to 34 weeks 6 days]; 62 male [50.0%]) allocated to the late group. A total of 159 full-term infants (median [IQR] GA, 40 weeks 0 days [39 week 0 days to 41 weeks 0 days]; 84 female [52.8%]) were included as the reference group. Information on the primary outcome was available for 226 preterm infants (88.6%) and 144 full-term infants (90.6%). At corrected age 2 years, the prevalence of overweight was 6.0% (95% CI, 2.7%-11.5%) in the early group and 5.5% (95% CI, 2.3%-11.1%) in the late group. For obesity, the prevalence was 1.7% (95% CI, 0.3%-5.5%) in the early group and 1.8% (95% CI, 0.3%-5.9%) in the late group. The full-term reference group showed a higher prevalence of overweight (9.0%; 95% CI, 5.1%-14.6%) and obesity (3.5%; 95% CI, 1.3%-7.5%). Conclusions and Relevance In this randomized clinical trial of preterm infants, initiating complementary feeding between corrected age 12 and 17 weeks did not affect overweight and obesity prevalence at corrected age 2 years. Trial Registration Onderzoekmetmensen.nl Identifier: NL-OMON53076