New research supports calls to decrease or remove the lower limit of current recommendations for pregnant women with obesity

New study finds pregnancy weight gain below the current minimum recommended by the U.S. Institute of Medicine (IOM) for obese patients - did not appear to increase their risk for maternal and foetal complications.

Studying 15,760 pregnancies with a body mass index of 30.0 to 39.9, pregnancy weight gains below the 5 kg recommended did not significantly increase risk of adverse outcomes reported Kari Johansson, PhD, of the Karolinska Institute in Stockholm, and co-authors.

For women with class 3 obesity (BMI ≥40.0), weight gain below the IOM lower limit or weight loss actually had a reduced risk of the adverse composite outcome (adjusted RR 0.81 at 0 vs 5 kg weight gain, 95% CI 0.71-0.89), the researchers reported in The Lancet.

Ultimately, the authors concluded that less pregnancy weight gain, or even weight loss, was safe for obese patients.

Kari Johansson, PhD, of the Karolinska Institute in Stockholm said: "Our findings support calls to lower or remove the lower limit of current IOM recommendations for pregnant women with obesity and suggest that separate guidelines for class 3 obesity might be warranted.”

“Re-evaluating these guidelines may help to reduce the high burden of poor maternal and infant health outcomes associated with pre-pregnancy obesity.”