Tailbone Pain (Coccydynia)

What It Is & Why It Happens

Tailbone Pain, clinically known as coccydynia, is a musculoskeletal symptom during pregnancy characterized by a dull or sharp ache at the very base of the spine, just above the buttocks. It is a common discomfort, affecting up to 15% of pregnant individuals, particularly in the third trimester.

The primary cause is the hormone relaxin. Relaxin softens and relaxes the ligaments and joints in the pelvis to prepare for childbirth. This includes the joints connecting the tailbone (coccyx) to the sacrum.

As these ligaments loosen, the coccyx becomes more mobile and less stable. At the same time, the weight of the expanding uterus and the physical pressure of the baby’s head (especially when they drop into a head-down position) presses directly against the sacrum and coccyx.

Changes in your posture and gait to compensate for your growing belly also strain the pelvic floor muscles attached to the tailbone, pulling on the joints and causing localized pain, particularly when sitting.

Typical Timeline

Tailbone pain typically begins during the second trimester (around Week 20) and can intensify during the third trimester (Weeks 28-40) as the baby grows larger and drops lower into the pelvis. Coccydynia generally resolves in the weeks to months postpartum as ligaments tighten and posture returns to normal, though it can persist longer if joint inflammation was severe or if the tailbone was bruised during delivery.

Safe Comfort Measures

You can safely manage tailbone pain and reduce joint pressure with these self-care guidelines:

• Use a Donut or Wedge Cushion: When sitting, use a donut-shaped pillow or a V-shaped wedge cushion with a cutout at the back. This suspends your tailbone in the air, preventing it from bearing direct weight against the seat.
• Lean Forward When Sitting: If you must sit on a flat chair, lean slightly forward at the hips to shift your weight onto your thighs and pubic bones rather than sitting back on your tailbone.
• Apply Heat or Cold: Apply a cold pack wrapped in a towel to the tailbone area for 10 to 15 minutes to numb pain and reduce inflammation. Alternatively, a warm compress or warm bath can soothe surrounding tense muscles.
• Avoid Hard Seats: Avoid sitting on hard, unpadded surfaces for long periods. Stand up and stretch or walk around every 30 to 45 minutes.
• Sleep on Your Side: Sleep on your side with a pillow between your knees to keep your hips aligned and reduce stress on your pelvic ligaments.
• Perform Gentle Pelvic Tilts: Perform gentle pelvic tilts on hands and knees (cat-cow stretch) to help release tension in the pelvic floor and lower back muscles.
• Consult Your Provider: Speak to your healthcare provider or midwife about your tailbone pain. They can evaluate the joints and recommend prenatal physical therapy or chiropractic care if the pain is severe.

When to Call the Doctor (Red Flags)

While coccydynia is usually a benign musculoskeletal issue, severe or worsening pain can mask complications.

Contact your healthcare provider if you experience:

• Severe, sharp, or constant tailbone pain that makes sitting, standing, or walking impossible.
• Tailbone pain accompanied by regular, rhythmic abdominal cramping, pelvic pressure, or low back pain before Week 37 (signs of preterm labor).
• Any vaginal bleeding, spotting, or a sudden leak or gush of fluid.
• Numbness, tingling, or weakness in your groin, perineum, or down one or both legs.
• Pain that worsens progressively postpartum or is accompanied by a fever or signs of infection around the sacrum.