What is the 'belly pump,' and is it safe for pregnant women and their babies?

It looks like a time-lapse video of a pregnant belly growing and shrinking, but it's not — using an exercise called the Bloom Method, pregnant women are expanding and contracting their abdominal muscles through diaphragmatic breathing, pulling their unborn babies deeper into their abdomen as they inhale, and pressing them forward as they exhale.

Why? And, is it safe? Experts say it's perfectly fine, though they note that the special technique probably won't help pregnant women any more than regular yoga, Pilates or other core-strengthening exercise.

Videos of women practicing the Bloom Method, created by Colorado personal trainer Brooke Cates, have gone viral, prompting questions about the unusual-looking abdominal and breathing exercises.

"The reason the belly gets smaller is not because the woman is sucking in, but because she's using her inner core unit," Cates explained. "She's inhaling with the diaphragm as the belly gets bigger and then on the exhale, she's lifting through the pelvic floor and starting to wrap the transverse abdominal muscles — it's like she's using her muscles to hug her baby."

Cates, 35, who has no children, said her method is not just about the "belly pump" — it's about "redefining pregnancy exercise by providing women with really simple, effective tools that they can add into any methodology of fitness that they would want to."

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Prenatal experts applaud Cates's approach to helping women stay strong and healthy during pregnancy — but, they say there's little evidence for her other claims about the Bloom Method. Among other things, Cates claims on her website and on Instagram that her fitness program can help prevent loose skin, stretch marks, back pain, incontinence and abdominal separation. Her fees range from $28 for a drop-in class to nearly $2,000 for a full class and coaching package.

"The only problem I see with the Bloom Method is what she says on her website," said renowned obstetrician Dr. Jaques Moritz, an OB-GYN at Weill Cornell Medicine in New York. "Stuff like that she can prevent stretch marks, which are often caused by genetics, or that it's going to lead to an easier birth — I mean, hallelujah if it does, but I don't think there's any guarantee."

Moritz told TODAY Parents that he's noticed that women who practice yoga or pilates during their pregnancies tend to have a strong core and are able to produce more force with their abdominal muscles when pushing. Because the Bloom Method appears to teach similar exercises, Moritz says he believes it could benefit pregnant women.

"I don't think it's going to hurt," said Moritz. "I think the idea of learning about and controlling your abdominal muscles are great — you're using them a lot for pushing a baby out, there's no doubt about that."

"Anything that gets people more in touch with their core and their ab muscles, if it helps them control their body and strengthen their body, I do think that will greatly help them," continued Moritz, adding that he'd like to see a study conducted to determine the effectiveness of the Bloom Method.

Dr. Donnica Moore, a New Jersey-based OB-GYN, women's health expert and advocate, said while there is no clinical evidence to support Cates' claims, she does not believe the program is harmful to mom or baby. In fact, it may help.

"Training and exercises will help you strengthen your abdominal muscles," said Moore. "Exercise before pregnancy, during pregnancy, and after pregnancy is a very good thing, so long as you have discussed it with your doctor."

Moore also cautioned against the claims made on Cates's website, explaining that there have been no medical studies to prove that the program helps women heal faster after delivery or can prevent diastasis recti, for example.

"The benefits listed on her website are not substantiated by any kind of research that I'm aware of," said Moore.

Cates said she hopes that one day there will be a study of her methods. In the meantime, she says she tracks her clients and loves to hear that her fitness method has helped them during pregnancy and during recovery.

"I believe in prevention because I don't feel like women should be broken once they step into motherhood," Cates said. "The goal is to help every mama keep doing what she wants to do."

A quick tutorial on our infamous "Belly Pump" aka diaphragmatic belly breath + core activation. This exercise is just one of the foundational techniques used within The Bloom Method - we believe it to be a an incredible teacher in correct breath work, core connection , and mindfulness, among many others. We have our clients implement this amazing tool in various ways throughout pregnancy and believe that it's one of the reasons our average first time mom is experiencing a birth pushing rate of less than 30 minutes, a more comfortable pregnancy, and a decrease in abdominal separation, PF incontinence, prolapse and other pregnancy related pains. Try adding this into your daily routine - try it sitting at a desk, brushing your teeth, during meditation, commuting to and from work, during your workout and other daily activities that you take part in. The idea is that it's easily implemented, making your modern mom life, a lot easier. Of course this exercise can be expanded on and there are tons of ways to implement and reap its benefits but in the fashion of keeping it simple and our limited ability to educate via social media, "JUST BREATHE" diaphragmatically that is and add the core activation during the exhale! #37weekspregnant #fitpregnancy #fitfam #fitmom #fitbump #fitmamas #prenatal #pregnantcore #prenatalworkout #thebloommethod #bellypump #bellypumping #bellybreathing #strongcore #prenatalcore #redefiningpregnancyexercise #prenatalexercise #pregnancyfitness #pregnancyexercise #birthprep #birth #laborprep #labor #midwife #doula #safeprenatalfitness #diaphragmaticbreathing #fitforbirth @fitpregnancy @babble @babycenter @popsugarmoms @popsugarfitness @scarymommy @redbookmag @cafemomofficial @daily_mail_online @thelunacenter

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