Mind the gap
A diastasis of the rectus abdominis muscle is a gap that
has formed between the two bellies of the rectus abdominis, or
"six-pack" muscles. During pregnancy, as the uterus grows in size,
the stomach muscles must stretch to accommodate this. Towards
the later stages of pregnancy many women notice a bulging or dome
shape in the middle of their abdomen when they perform activities
like getting up off the floor or out of the bath. So what exactly
is it, and what should women do about it?
The rectus abdominis is the most superficial of all abdominal
muscles, meaning that in people with low body fat, the rippled
outline of the muscle can sometimes be seen just below the surface
of the skin, hence the term six-pack. It runs from the end of the
sternum (chest bone) right down the centre of the abdomen and
inserts into the pubic bone. Its main function is to help flex the
trunk, or perform an action like that of a sit-up or abdominal
crunch. Running centrally between the two bellies of the muscle is
a region of connective tissue called the linea alba. In many
pregnancies, this connective tissue can stretch apart or separate.
When this happens, many women will become aware of a
characteristic bulge around the area of the belly button when they
perform certain activities, such as getting out bed.
According to the literature, a
diastasis or separation of the rectus abdominis (DRA) muscles
occurs in approximately 35-62% of pregnant women and is most
commonly seen in the second and third trimesters. The diastasis may
range from a small 2-3 cm gap, to a 12-20cm separation, most
commonly seen at the level of the umbilicus or belly button, but
potentially extending the whole length of the muscles. Hormones
released during pregnancy cause softening of the joints of the
pelvis and spine. This hormonal infuence is believed to be one of
the predisposing factors in DRA. In addition, the mechanical strain
placed on the abdominals by the enlarging uterus is another
Am I at risk?
Risk factors such as older maternal age, having your second or
further child, multiple gestations, larger babies and a larger
overall weight-gain for the mother have all been reported in
studies. It is important to note however, that it is still quite
possible to have a woman in her first pregnancy, with a relatively
small abdomen, but quite a large separation when measured for DRA
post-natally. I quite frequently see this when teaching post-natal
classes. A possible explanation is that we all have differences in
our connective tissues - a prime example being that many lean women
still experience stretch marks, while some larger women have never
seen one in their lives!
It is thought that the presence of
already weakened abdominals, or incomplete recovery from a previous
pregnancy, may be related to the higher incidence of DRA in second
and subsequent pregnancies. In addition, any repetitive activity
that results in an increase in intra abdominal pressure (such as
lifting other children, coughing etc) can lead to the development
or worsening of DRA. Some studies have also shown a link between
DRA and a lack of regular exercise during pregnancy.
For some women, a DRA is a normal change associated with
pregnancy. However, if a woman is unaware of this condition she is
more likely to unintentionally exacerbate the problem by performing
activities that may make it worse. Similarly, while some small DRAs
will resolve spontaneously in the post-natal period, others may
not. A large diastasis left unattended may not resolve and can lead
to problems such as decreased control of the spine, worsening
low-back pain, abnormal posture, and possible cosmetic defects. A
recent study published in the International Urogynecology Journal
even found that there was a relationship between the presence
of a DRA and incontinence.
How to check for DRA
If you are pregnant, or in the early post-natal period, and have
noticed the characteristic bulge, I would recommend asking your
midwife, physiotherapist or obstetrician to check it for
you. If you have already had your baby, you can do a
self-check for a diastasis at any point in the postnatal
Lie down on your back with your
knees bent. Then place your fingers length ways (pointing towards
your pubic bone), in the middle of your abdomen at the level of
your belly button and press gently towards the floor. Now lift your
head and shoulders off the floor, pressing down with your fingers
at the same time. If you can feel the edges of the rectus muscles
on either side of your fingers then this may indicate a gap or DRA.
A gap of approximately two fingers or less is considered relatively
minor and not a problem. As a general rule, anything larger than
this requires attention. If you find this hard to feel, or aren't
sure but still concerned that you may have a gap, then ask your
midwife, physiotherapist or doctor to check it for you. Not all
health professionals in New Zealand routinely screen for DRA, so
you may need to ask.
I have a gap. What should I do?
During pregnancy, I would recommend certain activity modifications
where possible, along with regular activation of the
transversus abdominis (TVA) muscle. This is the deepest of the
abdominal muscles and functions a bit like a corset to help
stabilise the spine and pelvis. By bracing your TVA, you are
actively helping support your spine and this can assist in
decreasing the characteristic bulging of the abdominal wall during
Core muscle (TVA) activation: Start
by sitting well supported, or lying on your side with a gentle
curve in your lower back (neutral spine). Now let your abdomen
relax completely. Very gently draw your lower tummy area towards
your spine. The movement should be very subtle. Ensure you aren't
sucking in your ribs and that you continue to breathe gently.
Nothing above your belly button should move. Then relax completely
and let it go.
Some women find that their pelvic
floor muscles contract gently when they do this, which is normal.
If you are still pregnant, you might like to think of this exercise
as gently "hugging" your baby. TVA activation can be done regularly
throughout pregnancy and the post-natal period to help strengthen
this region and to help your muscles recover post-natally. It is
safe to do after a C-section or with a large DRA.
Recommendations during pregnancy
Avoid sit-ups. These place unnecessary stress on the abdominal
muscles and it isn't a good idea to lie flat on your back after the
Engage or brace your TVA every time
you perform an activity such as picking up other children, lifting
the washing basket or groceries etc.
When getting out of bed,
engage your core (TVA) by flattening the lower tummy and roll onto
your side while pushing up through your arms, rather than hauling
yourself up with your tummy muscles.
When getting into or out of the
bath, use your arms rather than your abdominals to help yourself in
and out, and don't forget to engage your TVA muscle.
Try and avoid any activity that
causes the characteristic bulge to occur. For example, use the
ladder to get out of the swimming pool, rather than hauling
yourself up with your arms and abdominals.
If possible attend a physiotherapy-based post-natal class while
still in hospital, or ask your midwife or doctor to check your
tummy for you. If a significant DRA is found, you should
ideally be referred to a women's health physiotherapist.
Try to wear supportive underwear,
or a long fitted top such as a tube top, under your clothing for a
few weeks after the birth. This provides external support and
proprioceptive feedback to the abdominals (reminding them which
direction we want them to go in).
Avoid any heavy lifting where possible, for at least six weeks. If
you do have to lift something (like another small child), make sure
you engage your TVA to provide extra support. This is even a good
habit to get in to when lifting up your baby.
Avoid carrying heavy and awkward
baby capsules. Leave them in the car and transfer baby to a sling
or a push-chair.
Make sure you are doing regular TVA
holds. In the immediate post-partum period, start in side-lying
position and try holding for five to six seconds at a time,
repeating up to 10 times. Ensure you don't hold your breath, and
try and do them regularly throughout the day, such as when feeding
Avoid any crunches or sit-ups, as
this could make the separation worse or prevent it from
Be sure you are also doing pelvic
floor exercises. Ask your LMC if you are unsure, or go to www.filifit.co.nz and check
out the free information on pelvic foor exercises.
When you feel comfortable, it is
fine to gradually return to a low impact exercise such as
walking. Always be aware of your posture and avoid any activity
that places pressure on your recovering abdominal muscles.
Ideally, you need to progress your
abdominal stabilisation exercises. This is best done under the
guidance of a women's health physiotherapist.
Lisa Yates is the mother of two young girls and an experienced
physiotherapist with a special interest in women's health. She
is passionate about obstetric and continence physiotherapy and is
also a women's personal trainer and wellness coach. Together with
Fiona Ross, an experienced midwife and personal trainer, she
founded FiliFit Ltd to help nurture healthy lifestyles. The
Core & the Floor DVD (available from www.filifit.com) is new
Zealand's first post-pregnancy exercise programme designed by
health professionals. This comprehensive DVD demonstrates
everything you need to know to safely and effectively get in shape.
Lisa and Fiona share a passion for educating and empowering women
to "be the best they can be".
Further information and
* Spitznagle, TM, Leong FC, and van Dillen LR. "Prevalence
of diastasis recti abdominus in urogyecological patient
population." International Urogynecology Journal. (2007) 18:
* Teresa, L, Candido, G, & Janssen P. "Risk factors for
diastasis of the recti abdominus." Journal of the Association of
Chartered Physiotherapists in Women's Health. Autumn (2005) 97:
* Teresa, L, Candido, G, and Janssen P. "Diastasis of the
Recti Abdominus in Pregnancy: Risk factors and treatment."
Physiotherapy Canada. Winter 1999): 32-37.
* Gilleard, WL, Brown, MM. "structure and function of the
Abdominal Muscles in Primigravid subjects During Pregnancy and the
immediate Postbirth Period." Physical Therapy. July (1996) 76:
* Sapsford, R, Bullock-saxton, J, Markwell, s. Women's
Health: A Textbook for Physiotherapists. WB saunders Ltd (1998) pgs
* Boissonnault, JS, Blaschak MJ. "Incidence of Diastasis
During the Childbearing Year." Physical Therapy. July (1988) 68:
* Bursch, GS. "interrater Reliability of Diastasis Recti
Abdominus Measurement." Physical Therapy. July (1987) 67:
* The Core & The Floor: Your Complete Post-Pregnancy Education
and Exercise Programme. Available via: www.filifit.com
As seen in OHbaby!
magazine Issue 5: 2009
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