The Impact of the Relaxin Hormone Antenatally and Postnatally and How an MSK Physio Can Help

Pregnancy and the postnatal period involve significant physical change. One of the hormones often discussed in this context is relaxin. It is commonly associated with increased laxity and a feeling that the body is less stable, particularly through the pelvis, hips and lower back.

While relaxin is only one part of a much larger picture, it can help explain why some people feel physically different during pregnancy and after birth.

At our clinic in Marrickville, we see antenatal and postnatal patients from across the Inner West dealing with pain, reduced load tolerance and uncertainty around how to exercise safely. This is where a musculoskeletal physio can be helpful.

What does relaxin do?

Relaxin is a hormone involved in supporting pregnancy-related changes in the body. It is often discussed in relation to ligament laxity and changes in passive stability, particularly around the pelvis.

In practical terms, this can mean some people feel:

• less stable through the pelvis
• more sore through the lower back
• more aware of hip, pubic or sacroiliac region discomfort
• less tolerant of positions or loads that previously felt easy

Not everyone experiences these issues, and not every ache in pregnancy is due to relaxin, but it can be part of the broader load and stability picture.

Antenatal considerations

During pregnancy, people may notice discomfort with:

• walking
• rolling in bed
• stairs
• single leg tasks
• exercise that previously felt straightforward

Common presentations include pelvic girdle pain, lower back pain, hip pain and rib discomfort. As pregnancy progresses, posture, breathing mechanics, abdominal wall demand and general movement patterns also change.

Postnatal considerations

Postnatally, the conversation often shifts to rebuilding tolerance. This may involve:

• returning to walking comfortably
• lifting and carrying a baby
• regaining confidence with exercise
• managing pelvic, lower back or abdominal symptoms

Even once pregnancy is over, people do not instantly return to full physical capacity. Load tolerance often needs to be rebuilt gradually.

How an MSK physio can help

A musculoskeletal physio can help by assessing the specific drivers of pain and reduced function, then building a plan that is realistic for the stage you are at.

This may include:

• strength and control work
• exercise modification
• load management advice
• guidance around returning to walking, gym or running
• hands-on treatment where appropriate

For some patients, broader women's health or pelvic floor input is also appropriate.

The key point

Pregnancy and the postnatal period place different demands on the body. Relaxin may be one part of why the body feels less stable or more physically sensitive, but good management is rarely about simply 'being loose'. It is usually about understanding load, improving muscular support and building back confidence gradually.

If you are in Marrickville, Enmore, Newtown, Stanmore or elsewhere in the Inner West and are dealing with antenatal or postnatal musculoskeletal pain, our team can help guide safe, sensible progression.

Links: Pregnancy Massage | Chronic Pain | Massage Therapy