In a prospective study of 18,481 pregnant women in China who had never given birth before, obesity in early pregnancy was linked to higher risks of spontaneous abortion, preterm birth, and large birth weight in newborns.
In the Obesity study, being underweight during pregnancy was linked to higher risks for early neonatal deaths, as well as low birth weight.
The findings point to the importance of an appropriate weight before and during pregnancy.
"Women who plan pregnancies and their prenatal care providers may wish to weigh these findings to decrease the related risks," said senior author Dr. Jianmeng Liu, of the Peking University Health Science Center, in China.
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