Hip pain during pregnancy is a common experience, affecting nearly one-third of expectant mothers, particularly in the second and third trimesters. This discomfort, which can range from a dull ache to a sharp, debilitating pain, is a recognized part of the body’s adaptation to accommodate a growing baby. While the sensation can interfere with daily activities like walking or sleeping, it is typically a result of normal physiological changes. Understanding the reasons behind this discomfort can help manage the symptoms and differentiate between expected aches and a condition requiring medical attention.
General Physiological Shifts Causing Hip Discomfort
The primary changes causing hip discomfort are related to hormonal shifts and biomechanical adjustments that prepare the body for childbirth. The hormone relaxin is produced early in pregnancy and circulates at high levels throughout. Relaxin functions to soften and loosen the ligaments and connective tissues surrounding the joints, including those in the pelvis and hips.
This increased flexibility, while necessary for birth, can lead to instability in the joints, particularly the sacroiliac joints in the pelvis. The resulting joint laxity causes surrounding muscles to work harder to maintain stability, which can lead to fatigue and soreness in the hip area.
Weight gain and the shifting center of gravity further compound this mechanical stress. As the uterus expands, the body’s center of mass moves forward, causing a compensatory arching of the lower back, known as lordosis. This postural change places additional, uneven mechanical stress on the hip joints and supporting muscles.
The increasing size of the uterus can also lead to direct pressure on surrounding structures. The growing baby and uterus may press on nerves or blood vessels, contributing to pressure, aching, or numbness in the hip and thigh region. This combination of hormonal influence, increased load, and altered posture explains much of the common hip pain experienced during pregnancy.
Understanding Pelvic Girdle Pain and Other Specific Diagnoses
While general aches are common, more specific or severe pain may be caused by diagnosable conditions like Pelvic Girdle Pain (PGP). PGP, historically referred to as Symphysis Pubis Dysfunction (SPD), describes pain and instability in the joints that make up the pelvic ring.
PGP is characterized by pain over the pubic bone at the front, across the lower back, or in the inner thighs. It may also involve a grinding or clicking sensation in the pelvis. This condition occurs when the pelvic joints, including the sacroiliac joints and the symphysis pubis, move unevenly or become unstable due to ligamentous changes. Pain from PGP is made worse by activities that involve standing on one leg, such as climbing stairs, getting dressed, or turning over in bed.
Another distinct source of pain is sciatica, which involves irritation or compression of the sciatic nerve. This nerve runs from the lower back through the hips and down each leg. During pregnancy, the expanding uterus can directly press on the sciatic nerve where it passes through the pelvis. Alternatively, the change in posture can cause tight muscles in the buttocks, like the piriformis, to compress it.
Sciatica presents as a sharp, shooting pain, numbness, or tingling that radiates from the hip or buttocks down the back of the leg. Unlike PGP, which is related to joint instability, sciatica is nerve-related pain caused by direct pressure or inflammation. Recognizing the specific nature of the pain is important for effective management.
Practical Strategies for Managing Pain at Home
Simple modifications to daily habits can provide relief from hip discomfort. When sitting, use a firm, supportive chair and avoid crossing the legs, which can worsen pelvic imbalance and strain. Maintaining good posture while standing, by avoiding excessive arching of the back, helps keep weight evenly distributed across the hip joints.
Adjustments to sleeping positions are effective for night-time hip pain. Side sleeping is recommended during later pregnancy. Placing a pillow between the knees and ankles helps keep the hips, pelvis, and spine in better alignment, reducing joint pressure. Specialized full-length pregnancy pillows provide comprehensive support.
Gentle, low-impact movements can help maintain muscle strength and flexibility without straining the loosened joints. Activities like walking, swimming, or prenatal yoga are beneficial. Applying a warm compress to the painful hip or lower back area for 10 to 15 minutes can soothe tense muscles and increase blood flow.
Supportive devices, such as a maternity belt or pelvic support belt, offer external stability to the pelvic joints throughout the day. These supports help reduce strain on the ligaments and muscles by holding the pelvis more securely. Avoiding activities that aggravate the pain, such as standing for long periods or lifting heavy objects, is also a sensible approach.
When to Contact a Healthcare Provider
While most hip pain during pregnancy is manageable, certain symptoms indicate a need for medical evaluation. Contact a healthcare provider if the pain is sudden, severe, or so debilitating that it prevents walking or bearing weight on your leg.
Pain that persists for more than a couple of weeks despite consistent rest and home management should be discussed with your doctor or midwife. Any sharp, shooting pain, numbness, or weakness in the leg that does not improve may signal nerve compression.
It is important to seek prompt medical attention if hip pain is accompanied by other concerning symptoms. These include:
- Fever.
- Vaginal bleeding.
- Signs of preterm labor, such as regular, strong contractions.
- A sudden change in vaginal discharge before 37 weeks of pregnancy.