FRIDAY, March 8 (HealthDay News) -- Overweight and obese pregnant women are at increased risk for cesarean delivery, according to a new study.

Researchers examined data from more than 50,000 women in Norway who gave birth to one child. Women with preeclampsia, high blood pressure, diabetes, gestational diabetes and placenta previa were not included in the study.

The findings were published online recently in the journal Acta Obstetricia et Gynecologica Scandinavica.

Women who were overweight and obese before pregnancy had an increased risk of C-section. Those who were extremely obese had the strongest risk of C-section and also had an increased risk of vacuum-extraction delivery.

The researchers also found that women who gained 35 pounds or more during pregnancy had a significantly increased risk of forceps, vacuum-extraction and C-section deliveries. This finding was independent of a woman's weight before pregnancy.

In 2008, 1.4 billion adults worldwide were overweight and more than 500 million were obese, according to the World Health Organization. In the United States, about one-third of adults were obese in 2009 and 2010, according to the U.S. Centers for Disease Control and Prevention.

"With such alarming rates of obesity, understanding its impact is an important health issue, particularly for women in childbearing years," study author Dr. Nils-Halvdan Morken, of the University of Bergen, said in a journal news release.

Although the study tied being heavier in pregnancy to a higher risk of C-section, it did not establish a cause-and-effect relationship.

Although other factors may contribute to an increased risk of C-section and vacuum-extraction delivery, doctors need to be aware of the impact that being overweight and obese can have on pregnancy and delivery to properly advise women considering having children, Morken concluded.

More information

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