Understanding Relaxin: How This Powerful Hormone Affects the Body During Pregnancy and Postpartum
Pregnancy is nothing short of miraculous—and it brings with it some major shifts in a woman’s body. No secret here.
Our bodies are flooded with additional hormones, blood cells, and other substances that make them run the way they do. One key player in these changes is a hormone called relaxin. While its name sounds, well, relaxing, relaxin is actually hard at work behind the scenes, helping the body prepare for pregnancy, labor, and delivery.
Why would it be important for someone to understand this hormone?
If you’re experiencing things like joint pain, pelvic discomfort, or a sense of “looseness” in your body- chances are this hormone is doing it’s job.
But first, what exactly is RELAXIN?
And what does it do during pregnancy and postpartum?
Relaxin is a hormone produced by the ovaries and placenta during pregnancy. It starts to rise in the first trimester and continues to fluctuate throughout pregnancy, with substantial surges at key stages (like around ovulation and late pregnancy).
Basically, its primary role is to relax ligaments and soften connective tissue so the pelvis can expand and accommodate a growing baby—and eventually, birth
Prenatal bodywork can help reduce discomfort related to the hormone “Relaxin”
Where Relaxin Can Affect the Body During Pregnancy
As amazing as this hormone is, it doesn’t just work locally in the pelvis—it affects the entire body. That’s where many common pregnancy complaints come in.
Like:
Low back and Pelvic girdle pain (achy or sharp pain at the pubic symphysis (front of the Pelvis)
Hip Pain can come like soreness or a deep ache. Typically felt on the sides or in the groin area.
Sciatica-like symptoms - If you have tingling or shooting down the leg, pain.
Knee discomfort when standing, climbing stairs, or walking.
Foot and ankle pain (typically when your gait starts to change and you begin to get a bit unstable through your arches of the feet.
Rib pain or sorensses in the chest cavity. (To help the ribs shift more easily)
Shoulder and or neck tension. When your posture changes to compensate for loosened lower joints.
How you may feel it in your body
Feeling of “instability” – especially in hips, pelvis, and low back when walking or moving.
Joint clicking or shifting – SI joints and pubic symphysis often feel like they "move" or crack more.
Increased risk of sprains/strains – ankles, wrists, and knees are more vulnerable.
What is relaxin doing behind the scenes:
Pelvic joint softening: It widens the pelvis and softens the pubic symphysis to allow for labor and delivery
Ligament laxity: It increases laxity (looseness) in ligaments throughout the body, which can lead to joint instability.
Postural shifts: As the baby grows and the center of gravity changes, loosened ligaments can make it harder to maintain stability—leading to low back pain, sacroiliac (SI) joint pain, or even balance issues.
Increased risk of injury: Joints like knees, ankles, and wrists may feel more vulnerable during pregnancy due to this hormonal effect.
How it may feel in the body:
Feeling instability, especially in hips, pelvis, and low back when walking. Expereincing clicking or shfiting in the SI joint and pubic symphysis can often feel like they “move” or crack more. An increase risk of sprains/strains in the ankles, writsts or knees.
Does it affect Postpartum?
Many people assume that once baby arrives, the body quickly returns to normal—but relaxin remains in the system for several months postpartum, especially if you're breastfeeding (since lactation hormones can sustain its presence).
This means:
Joint instability can linger—especially in the pelvis, hips, or spine.
Postpartum moms may still feel “wobbly” or experience discomfort with movement or exercise.
Core recovery and alignment work should be done gently and gradually.
Is there anything that can be done to help? Though we can’t (and don’t want) relaxin to not be in the body, as it has a very important job to do,
Understanding the role of relaxin helps explain why so many women experience musculoskeletal symptoms during and after pregnancy.
As a perinatal chiropractor, we take a gentle, supportive approach to care that honors these hormonal changes.
Here’s how Chiropractic help:
Pelvic alignment support: Assessing and adjusting the pelvis and SI joints will reduce discomfort and promote balance.
Joint stability strategies: Through tailored rehab exercises and movement education, we help rebuild strength safely.
Safe adjustments: We use techniques appropriate for your body’s stage—whether you’re in your first trimester or early postpartum.
Whole-body care: Because relaxin impacts the entire musculoskeletal system, we look beyond just one area to support full-body function and comfort.
Prenatal Massage
Will help by stabilizing and soothing the lower back and hips. When these muscles are worked, especially those around loosened joints, they provide extra support where the ligaments are most affected. Reduce your pelvic pain and tension by gently working to ease the discomfort around the sacrum. Circulation and swelling improve with massage when the legs are feeling heavy, there is ankle swelling, or you have varicose vein discomfort. Anything that aids and encourages postural balance will be beneficial for releasing overworked muscles. And, overall, it promotes relaxation for the nervous system. When you’re feeling unstable, having a moment to get a mind-body connection will make you feel calmer and more grounded.
Prenatal Acupuncture
It can add to the above benefits by relieving low back, hip, and pelvic pain. Targeting the points to help reduce inflammation and pain in areas strained by joint laxity. There is no turning off Relaxin, but acupuncture can help the body adapt better to changing hormone levels, ease nerve irritation (any tingling or shooting pains?) in the sciatica, or really anywhere in the body. Generally, this will support the overall Pelvic function by encouraging a better flow of Qi and blood through the uterus and pelvis. This can help the body adjust to the rapid changes your body is experiencing during pregnancy.
Relaxin is one of the many powerful hormones working hard to support your pregnancy and postpartum journey. While it plays an essential role, it can also contribute to the discomfort or instability many women feel during this transformative time.
The good news? With the right support and care, your body can adapt and thrive.
If you’re experiencing aches, joint pain, or feeling like your body just doesn’t quite “fit right” right now, know that you’re not alone—and we’re here to help. Book a Prenatal Massage, Acupuncture or Chiropractic appointment at any time during your pregnancy. It is often safe to receive body work early on in your pregnancy and will overall make the 9 months perhaps a bit easier to get through.