The enduring mystery of the postpartum pooch

Story highlights

  • Most women who give birth experience some degree of postpartum abdominal separation
  • Experts don't know what heals abdominal separation -- or whether it needs to be healed at all

(CNN)Culturally, the postpartum body is a source of abiding fascination. We are enthusiastic observers of women's shapes after childbirth and celebrate those who shed all evidence of pregnancy a few months after having a baby. These are the women who, as tabloids put it, "bounce back," even though few believe that the effort involved was akin to bouncing or any such rapid and organic movement.

Medically, the postpartum body is basically invisible. In the United States, women generally have just one appointment in this period, six weeks after childbirth, and it tends to be brief. (The American College of Obstetricians and Gynecologists recently recommended changing this.) We are largely -- and a little hopelessly -- on our own when navigating the various aches and dysfunction that pregnancy and childbirth leave in their wake.
Not only did I not bounce back after my pregnancies, but the notion of bouncing, in any direction, sounded awful. Like many women, I had postpartum abdominal separation, known clinically as diastasis recti abdominis and colloquially as mummy tummy: The connective tissue between my rectus abdominis, a.k.a. the six-pack muscles, had stretched out about 2 inches. I also was feeling quite unstable, and I assumed that these two things were related.
    Ob-gyns don't routinely screen for or discuss abdominal separation, despite the fact that up to 60% of women experience it to some degree during the first year postpartum and an estimated 33% are dealing with it beyond that. Many of us discover that we have it after experiencing pain, impaired mobility or, yes, the not-always-beloved lower belly pooch that tends to happen as a result.
    I was experiencing all of the above when I signed up for a postpartum rehabilitation class led by my yoga teacher. A dutiful student, I followed each and every instruction. I avoided crunches, which allegedly would widen the gap. And I worked hard on strengthening my transverse abdominis, the muscles that run up and down the sides of our midsections, which allegedly would bring it all together.
    Months passed, and I felt stronger, slimmer. But the gap remained. Did I fail at the regimen? Or, more likely considering my deep commitment, did the regimen fail me? Also, when, if ever, could I consider myself healed?
    Now, research shows that I was right to be suspicious. Doctors and physical therapists still don't know what heals abdominal separation -- or whether it needs to be healed at all.
    "It may not be fun to hear, but at the moment, we don't know how to fix it with the tools we have," said Dr. Elwin Mommers, who studies hernias at Maastricht University Medical Center in the Netherlands.

    Very little is known about diastasis recti

    Mommers is the lead author of a review of studies on abdominal separation published in December in the journal Surgical Endoscopy. He and his team sorted through all the available research on the topic and found that it offered very little in the way of clarity. There was a shortage of quality studies to draw conclusions from, and the few quality studies out there didn't yield any substantial findings.
    They couldn't find any evidence that physiotherapy brings together the gap or that one particular exercise plan is more effective than another. Yes, women who take up an exercise plan might leave it with a smaller gap -- but it's likely that the gap would have closed on its own, without the exercises. Mommers said women should see this as a reason to ignore any overly prescriptive exercise plans that prohibit things like back bends and crunches, and do what feels right for their bodies.
    " 'You can do anything you want' is the first thing we tell them. If you look at the studies, the exercises that are prescribed to treat it, or attempt to treat it, are completely opposite of each other. Some focus on stretching, others focus on pulling it all together, and none of them work," Mommers said.
    He added that many looking to document the benefits of an exercise plan measure the gap when the muscles are contracted. In this state, a stronger core might more effectively push together the center muscles and make it appear as though the gap has shrunk. The trick, he said, is to measure in a relaxed state in order to accurately determine results.
    Many believe that when the connective tissue between the abs is stretched out, it also becomes weaker, but Mommers says this isn't necessarily true. "If it were weak, then [people with abdominal separation] would be more prone to develop hernias, and there is absolutely no proof that abdominal separation eventually results in hernia," he said.
    Mommers' research also led to him conclude that although surgery can help close the gap and make the belly flatter, it doesn't necessarily lead to more stability. For now, it appears to be mostly a cosmetic fix.
    Another new study, published in the journal Physical Therapy, also casts doubt on the current consensus surrounding abdominal separation treatment. A group of Norwegian researchers looked at whether strengthening the transverse abdominis -- widely recommended, including by my instructor -- really works. It doesn't.
    Kari Bø, a professor at the Norwegian School of Sports Sciences and one of the study's authors, said the findings surprised her. She believed that such exercises were the solution. Now, she's not so sure.
    "It is a very prevalent condition, [but] unfortunately, the evidence behind any advice we give is very low or nonexistent," she said.
    The one recommendation she can make with some confidence is that "there should be no outward or visible opening up when doing abdominal exercise." So crunches and back bends are fine as long as the stomach isn't bulging out during them.
    Her research has also led her to cast doubt on whether the abdominal separation is really the cause of back and pelvic floor pain. She said studies show that the prevalence of such symptoms in postpartum women is not higher in those with mild to moderate separation, compared with those with no separation. "It may be that for many women, a tiny gap may not influence function."
    Still, Bø understands that a "cosmetic problem is still a problem" and is planning to study the way they can affect a woman's life.

    What women can do

    Even if core training doesn't help close the gap, it might help with the associated pelvic floor issues and back pain. Bø said there is strong evidence that training the pelvic girdle can help with urinary incontinence and pelvic organ prolapse. She said there is no evidence that specifically working the transverse muscles helps with back pain, among the general population. She is not aware of any studies looking specifically at those with abdominal separation.
    However, there is some evidence that overall core strengthening helps with lower back pain -- and there's little doubt that pregnancy and childbirth weaken the core, especially in the short term.
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    Wendy Powell, founder and CEO of MUTU System, an online exercise program for postpartum recovery, said that women with back pain or pelvic floor issues should focus more on alignment and strength and less on the gap.
    "It's not all about gap. That's a disservice. The idea that this gap is the problem and closing it is the solution -- we are missing what matters," she said.
    Powell said women should look for exercise programs that take the whole body into account, not just isolated muscles. "To me, success looks like function, a body that works, that doesn't hurt, that doesn't leak, bulge, protrude or feel pressure."
    According to this definition of success, I seem to be mostly healed. My body works just fine now. There's not much in the way of pain, leaking or bulging when working out my core. Just last night, I bounced around the living room with my two children without fear of retribution from my midsection.
    But that gap? Unless I opt for what I now know would be entirely cosmetic surgery, it appears to be here to stay.