PALM SPRINGS, Calif. -

Alyssa Meyers went all out on her first pregnancy. 

"Watching the movies you think, 'Oh, I can eat ice cream, sweets, whatever,'" she said. 

The second time around, though, "Just eating smaller portions more regularly. Choosing the healthy things."

Alyssa joins many other women wanting to stay in shape while pregnant. A major difference - she didn't become "pregorexic."

Pregorexia is a trend among some pregnant women - who intentionally don't eat enough for two in order to stay skinny. It's not a formally recognized medical diagnosis, rather a term creating some buzz. Often women in their second pregnancy try harder to stay skinny and not gain like they did the first time around. We talked to Dr. Ralph Steiger, who specializes in high risk pregnancies. 

"The highest risk group is the woman who is underweight to start with then doesn't gain weight," Dr. Steiger said. 

Dr. Steiger said he often sees this in younger, thinner patients -  and it's very bad for the baby. 

"If the baby doesn't grow well because of the environment, they usually catch up to their normal weight, but the concerns are developmental delays," he said. 

Dr. Steiger understands pressure coming from society, as we watch one celebrity after another stay skinny during pregnancy, or lose baby weight in the blink of an eye.  

"Its unhealthy and it's not an optimal environment for a baby to grow in," he added. 

Dr. Steiger gives a handout to each of his patients outlining appropriate pregnancy weight gain. Women who are an average healthy weight for their size should gain about 25-35 pounds. However, a women who is underweight should gain 28-40 pounds. 

Alyssa said she'd love to have stayed thinner during and after pregnancy.

"You try as much as you can. There's a lot more I'd like to do. I'd like to lose a lot more weight but you have to take it in stride and do what you can," she said. 

However, she said what matters most -- bringing a healthy baby into the world.