(NEW YORK) -- One more worry in the country's obesity crisis: a new documentary highlights the perils of extra pounds during pregnancy.
The TLC special, Obese & Expecting, follows four obese women through complicated pregnancies and painful deliveries that put mom and baby at risk.
"We know that obesity during pregnancy increases the risk of diabetes and preeclampsia," said Dr. Marjorie Greenfield, chief of obstetrics and gynecology at University Hospitals Case Medical Center in Cleveland. "And when the mom is big, the baby can be big, raising the risk of birth injury and C-section."
A scene from the documentary shows doctors struggling to give one woman an epidural through the fat in her back.
"We spent 45 minutes attempting to put the spinal in," said Dr. Charles Hux, a New Jersey OB/GYN featured in the documentary. "With so many layers of fat, it's difficult to be certain that the needle went into the exact space it should go in."
After several tries, the team gave up, deciding instead to give the woman a general anesthetic and a C-section.
"Going to sleep carries significant risks, even for a slim pregnant woman," said Greenfield, calling the decision a last resort. "And the risk goes up significantly in a woman who's overweight."
Studies suggest nearly half of U.S. women who are of child-bearing age are obese, a problem that weighs heavily on doctors.
"It's harder to provide excellent care to someone who's obese because a lot of things we do are not as accurate," said Greenfield, explaining how ultrasounds and other tests to gauge the baby's growth can be skewed by the mother's fat. "It's also harder to feel the position of the baby."
That fat, and the fact that obesity can cause irregular periods, also means women might not realize they're pregnant.
"If you don't know you're pregnant, you might not avoid things that are toxic, like alcohol, smoking and certain medications," said Greenfield, adding that prenatal vitamins are also important. "And a lot of what we do in prenatal care depends on knowing exactly how far along a woman is. If you don't have a sense of gestational age, it's harder to provide the right care."
Obesity has also forced hospitals to adapt, adding delivery tables that can be made wider and hold up to 600 pounds, Greenfield said.
"The old tables only went up to 450 pounds," she said. "That's just not realistic anymore."
Weight gain during pregnancy is normal. But obese women should gain no more than 15 pounds, roughly half the amount recommended for women of normal weight.
"For someone with bad eating habits, that's going to be really hard," said Greenfield, describing how pregnancy cravings and the "eating for two" mentality can conspire to pack on the pounds. "Lifestyle change is always hard. But during pregnancy, I think women are more motivated to do it for themselves and their baby."
Obese & Expecting premiered Thursday night at 9 p.m. on TLC.
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