Pelvic Girdle Pain in Pregnancy: Why It Happens and What Helps

What Pelvic Girdle Pain Is

Pelvic girdle pain (PGP) is felt around the sacroiliac joints at the back of the pelvis, the pubic symphysis at the front, or both, and can spread into the buttocks and thighs. The European guidelines describe PGP as a specific form of low back pain that can occur on its own or together with lower back pain, and note that it generally arises in relation to pregnancy, trauma, or arthritis. The point prevalence among pregnant women was estimated at about 20% (Vleeming et al., 2008).

Typical complaints include pain with walking, climbing stairs, turning in bed, standing on one leg, or getting in and out of a car.

Why It Happens

The exact mechanism is not settled. The guideline identified a history of previous low back pain and previous trauma to the pelvis as the most probable risk factors, while contraceptive pill use, time since the last pregnancy, height, weight and smoking were not considered risk factors (Vleeming et al., 2008). A systematic review similarly found that strenuous work and previous lumbopelvic pain increase risk, and that the processes behind disability remain unclear (Wu et al., 2004).

Hormonal effects on ligaments are often proposed as the explanation, but the evidence for any single mechanism is limited. Changes in load and in movement coordination are also likely to contribute.

How It Is Assessed

The guideline describes assessment through a history and a set of pain provocation tests around the pelvis, with the active straight leg raise used as a functional test. Routine X-ray, CT and other imaging are not recommended; MRI is reserved for situations such as suspected inflammatory disease or when red flags are present (Vleeming et al., 2008). In other words, a normal-looking scan is not needed to take the pain seriously.

What May Help, and When to Seek Review

The guideline recommends information and reassurance together with individualised exercise during pregnancy (Vleeming et al., 2008). A systematic review of physiotherapy modalities found strong evidence for pelvic belts and acupuncture, but only low evidence for exercise in general and for specific stabilising exercises, and advised caution with other interventions (Gutke et al., 2015). These findings are modest, which is why treatment is usually individualised and reviewed as pregnancy progresses.

Medical review is advisable for severe or constant pain, fever, numbness in the groin or genital area, changes in bladder or bowel control, a swollen painful calf, or any bleeding or reduced fetal movements. Which strategies suit a particular person depends on an assessment and on the guidance of the maternity care team.