From the Guidelines
Back pain during pregnancy is commonly caused by hormonal changes, weight gain, and postural adjustments, with low back pain (LBP) occurring in up to two thirds of pregnancies and pelvic girdle pain (PGP) occurring in nearly 20%. The hormone relaxin loosens ligaments and joints in preparation for childbirth, creating instability in the spine and pelvis 1. As pregnancy progresses, the growing uterus shifts your center of gravity forward, altering your posture and straining back muscles. Additional weight from the baby, placenta, and increased blood volume puts extra pressure on your spine. Other contributing factors include muscle separation (diastasis recti), stress, and prior back problems. Some key points to consider:
- LBP prevalence is most elevated in months 6 and 7 of pregnancy 1
- Severe cases of pregnancy-related LBP/PGP have been reported to trigger or exacerbate comorbid conditions, affecting patient well-being and functional status 1
- Occupational lifting and other physical job demands may also contribute to back pain during pregnancy, with evidence suggesting a small increased risk of lower birthweight for gestational age in relation to heavy physical work 1 To manage pregnancy-related back pain, consider the following:
- Maintain good posture
- Wear supportive shoes
- Avoid lifting heavy objects
- Use proper body mechanics when bending
- Sleep with supportive pillows
- Apply heat or cold packs
- Consider gentle exercises like swimming or prenatal yoga If pain is severe or accompanied by other concerning symptoms like fever or vaginal bleeding, consult your healthcare provider promptly as it could indicate a more serious condition.
From the Research
Causes of Back Pain During Pregnancy
- Back pain prior to pregnancy and multiparity are major predictors of back pain during pregnancy 2
- Biomechanical and physiologic changes during pregnancy, such as the stretching and weakening of abdominal muscles, contribute to back pain 2
- The production of the hormone relaxin, which increases ten-fold during pregnancy, creates joint laxity and weakens the ability of static supports in the lumbar spine to withstand shearing forces 2
- Joint laxity is most prominent in the symphysis pubis and the sacroiliac joints, leading to lumbar and sacroiliac back pain 2
- Hormonal changes, weight gain, and a shift in the center of gravity can lead to lumbar spine hyperlordosis and anterior tilting of the pelvis, causing low back pain and pelvic girdle pain 3
- Vascular changes may lead to compromised metabolic supply in the low back, contributing to back pain 3
- Adaptations in lumbar motion patterns and muscle responses, such as decreased lumbar maximum flexion and increased erector spinae activation, may be associated with the genesis of pregnancy-related low back pain 4
Types of Back Pain During Pregnancy
- Lumbar pain: characterized by discogenic pain and/or facet element pain, and may be most pronounced on flexion and standing 2
- Sacroiliac pain: associated with joint laxity in the sacroiliac joints 2
- Nocturnal back pain: a common type of back pain during pregnancy, although the exact causes are not well understood 2
- Low back pain and pelvic girdle pain: can occur separately or together, and may be related to hormonal changes, weight gain, and biomechanical changes during pregnancy 5, 3