Dr. Elizabeth Pryor answers the question, Is my baby too large? Will I need a c-section?

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My stomach is measuring large. The doctor said it was 30 and it should be 24 at this point. Is this something I should be worried about? Will I need a c-section?


What you are speaking of the fundal height. This is where the doctor uses a tape measure to assess the baby's weight and size.

The centimeters on the tape measure equals the number of weeks that the patient is pregnant. The measurement can be greater if there is extra fluid or it's a big baby. If a baby is large at term, an ultrasound can be performed to estimate the fetal weight. However, even with the best doctor and ultrasound machine, this weight can be off about 15 percent (over or under). This is why we don't like to do a c-section because what you think will be a big baby is actually a normal baby and the patient had surgery for no reason.

In fact, the baby's size alone should not determine a c-section. I have seen 10- to 12-pound babies slide out without a problem and 6-pound babies get wedged in the pelvis. The odds that the patient will have to have a c-section are about one in four.

The average weight for babies in our country at term is 7-1/2 pounds. So much of it depends on the type of pelvis the woman has, which of course is inherited. Certain races or ethnic groups are more likely to have c-sections than others. In my practice, I have found that asking the patient's mother, grandmother, sister, or aunt has provided a lot of information. Labor patterns tend to be similar within families.

The information on this Web site is designed for educational purposes only. It is not intended to be a substitute for informed medical advice or care. You should not use this information to diagnose or treat any health problems or illnesses without consulting your pediatrician or family doctor. Please consult a doctor with any questions or concerns you might have regarding your or your child's condition.

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