One More Reason to Watch Your Weight Gain During Pregnancy: An Easier Birth

Photo: Veer / The Bump
Photo: Veer / The Bump

New research presented today at the American College of Obstetricians and Gynecologists found that women who gained excessive weight during their pregnancies, resulting in large barbies, increases the risk for tears to the mother’s vagina during delivery. Our results were noteworthy — when the mother gains too much weight, it causes increased risk for tears during delivery.

From the study, researchers found that the most common injuries to the vagina during labor occurred at the vaginal opening, which may tear as the baby’s head passes through. For a “successful” vaginal delivery, the cervix must dilate at least 10 centimeters, but when a woman gains too much weight, the larger baby may increase risk for laceration to the mother.

A single institution retrospective chart review of 1,031 patients who delivered at term, or over seven months was performed. Patients were categorized into BMI classes at pre-pregnancy and term: normal weight (18-25), overweight (25-30) and obese (30 and above). Researchers found that about 30% of women who maintained a normal BMI during their pregnancies were tear-free at birth, but among women who became overweight during their pregnancies, only 20% did not have a laceration. For obese women, 9% had a “successful” tear-free delivery.

Diana Garretto, who was involved in the research, said that, “Excessive weight gain during pregnancy can result in larger babies, so we wanted to study whether there is increased risk for tears to the mother’s vagina during delivery.”

Tears that occur in the posterior portion of the vagina can vary in severity. First-degree lacerations (which mean the tar involves only the lining of the vagina) are the most common. A first-degree tear doesn’t typically bleed and may not require repair, but a second-degree laceration is when the tear extends into the submucosal tissues (which are the tissues just under the vaginal lining). These second-degree tears generally occur in the midline and extend backward toward the anus. They usually require surgical repair.

How did you maintain a healthy weight during your pregnancy?

Plus, more from The Bump:

How Can I Avoid Tearing During Delivery?

The Key to Healthy Weight Gain During Pregnancy

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