New research shows a direct correlation between weight and infertility.
A study published in the Journal Fertility and Sterility that looked at nearly 32,000 infertility treatments done in clinics in the United States found that 20 percent were more likely to fail in obese women.
The research supports previous studies that found excess fat can affect hormone levels or low-level inflammation throughout the body.
"Many women who are overweight have polycystic ovarian disease, which affects the ability to ovulate or produce an egg on a monthly basis," said Dr. Julie Thomas, an obstetrician/gynecologist at Baylor Carrollton.
Thomas said being underweight also can affect fertility.
"It tends to be more in athletes, women who are training multiple hours every day for competition-type exercise," she said.
Brandye Lewis, an avid dancer who spend eight hours per day in a studio or gym, struggled for years with infertility. She said she feared her lifestyle was holding her back from becoming pregnant.
"I would teach 18 to 25 classes a week, and that would be between the gyms and the dancing," she said. "But when your body is used to that, that doesn't seem like much."
"Some people would say, 'You're going to have to slow down. You're going to have to gain weight.' And, you know, I just listened to my body because that's the only thing I knew to do," Lewis said.
Lewis said she had in vitro fertilization and today is pregnant with twins.
"I think we're ready," she said. "You're never ready, but we are as ready as we know we can be. Ignorance is bliss, maybe."