Transcript for Mom-Shells: Struggling to Embrace Post-Baby Bodies
These days in hollywood, the baby bump is one of the most photographed fashion accessories. And after the baby arrives, news celebrity moms flaunt their taught arms and tight abs. But does all this attention hold women to a new and impossible standard? That's what one young mother thinks. And she is fighting back. Here's abc's juju chang. Reporter: There's a new breed of mom on the play ground. Just weeks after giving birth, she's back in skinny jeans and six-inch heels. Dubbed mom-shes, they're a hybrid of mommies and bombshells. From gwyneth paltrow to beyonce. They seem to be everywhere. These women who have infected our minds and you think about them all the time. When you look in the mirror, you say, why don't I look like jennifer lopez, jessica alba? Reporter: As the former editor of "us weekly," janice helped give birth to the mom-shell with the glossy body after baby spreads. You helped create this culture of baby bumps. This crazy shift happened where it was cool to be pregnant. You go out showing off your body after you have the baby and that was a way for the actresses to communicate to the world, I'm still sexy, I'm stick employable and you want to be like me. Reporter: But not everyone can look like gisele, shortly after childbirth. It's a standard even some celebs can't live up to. Like brice dallas howard, star of "the help." I drafted the sanitation initiative. The internet has been ruthless on her, calling her terrible names. It has to be incredibly painful. Reporter: But now, alison tate is leading a populist backlash. I felt dumpy and doubty, frustrated. Reporter: She had just given birth to her fourth chiltd when she did something many women do every day. Resisted taking a picture with her son at a birthday party. My 5-year-old son, who came up, said, mommy, come be in the photo booth with me, and my first reaction was -- no. Because I knew that I looked awkward and tired and, so, i didn't want to do it. Reporter: She had a lot of reasons to be confident. She had an ivy league education, happily married with four beautiful kids. What was wrong here? Even as I said no, I also thought, I need to just do this, because I have a 10-year-old. I know they don't ask you forever to be in pictures with them. Reporter: She wrote a blog about the experience and suddenly, the moment became a movement. Mom stays in the picture sparked a viral rallying cry. Thousands of women submitted their own pictures, even if they didn't look their best. You're not looking at whether the mom is overweight or did her hair omakeup. All you see are moms and their kids and all the love. Reporter: Perhaps surprisingly, janice can empathize, too. She, too, birth 6 months ago to baby number three and struggled. Was there a moment, postpartum, for you, where you thought, oh, my god, what have I done? Every moment postpartum was -- it's sort of horrifying. Afterwards, when the bump is gone, you're just kind of a fat lady and it's really harsh. Reporter: Her self-doubt inspired her to write a book to reassure real moms that looks can be deceiving. And celebrities go to sometimes unhealthy extremes to present a certain picture. We would have quotes from women, I cried, I work out so hard to lose this weight that i cry, that I don't eat, I'm always hungry. It's crazy things that celebrities do. Reporter: In "how to look hot in a mini van," she shares what she's learned from hollywood without taking such drastic measures. Statement necklace. Keep the eye away from the rest of your body. Let them focus on something else. Reporter: See, your outfit looks done. Do you think about it, that I've contributed to this? It played a part but I can't say we contributed to the meanness. Motherhood and weight are the two most loaded issues for women ever. When you put those together, it's care seen on a fire and women get obsessed. Reporter: One thing moms get obsessed with is other mom's weight gain. I've just had a lot of pressure on me, um, to lose the baby weight. Reporter: Jessica simpson has long been tabloid fodder but it reached fever pitch when she had her daughter, maxwell. She turned to harley passer the knack who helped her after the daisy duke period and is now helping to whip her back into shape. Getting her body back has turned into a sponsored event. I knew weight watchers was the only way to go. Reporter: But how about the people right now who are throwing things at the tv, who are like, fine, I can't afford harley, I can't have the shes and the cooks. Who do I do it? The truth is, I tell my clients, the key is walking. You don't need a trainer. You don't need anything fancy to walk. Reporter: Harley says he wants to make it easier for moms, so, he created a video avatar so you can work out while the baby is napping. Oh, my god. You're kicking my ass. A lot of people would say, you know, harley, you're responsible for making women feel bad, for not bouncing back right away. I would never make anyone feel bald about not bouncing back. I would be upset at someone for not taking care of their health. As a mom, you are setting an example for your child. Reporter: For alison tate, the more important example is love and acceptance for your children and for yourself. Our kids do not care what we look like. They only see their mother. And I just think that what women need to do is remember that you don't ruin their pictures. You complete them. Reporter: For "nightline," I'm juju chang in los angeles.
This transcript has been automatically generated and may not be 100% accurate.