Many expectant mothers wonder if their hips will change during pregnancy and if these changes are permanent. The body undergoes significant transformations to accommodate a growing baby. This article explores the physiological reasons behind perceived hip changes, how the pelvis adapts, and what to expect regarding postpartum recovery.
Pelvic Changes During Pregnancy
The primary physiological mechanism behind pelvic changes during pregnancy involves the hormone relaxin. Produced by the ovaries and placenta, relaxin increases significantly, peaking around the end of the first trimester. Its main function is to soften and loosen ligaments and connective tissues throughout the body, particularly those in the pelvis, to prepare for childbirth.
Relaxin affects the symphysis pubis, the joint connecting the two pubic bones, and the sacroiliac joints, which link the sacrum to the ilium. The loosening of these ligaments increases the mobility and flexibility of the pelvic girdle, allowing the pelvis to expand. This creates more space for the growing fetus and facilitates its passage through the birth canal during delivery. While the pelvis gains flexibility, this is due to ligament laxity and joint mobility, not a permanent alteration of the bone structure itself.
Broader Body Shape Changes
Beyond the specific changes to the pelvic joints, several other factors contribute to the perception of wider hips during pregnancy. Overall weight gain is a significant contributor, as the body accumulates additional weight from the developing baby, placenta, amniotic fluid, increased blood volume, and enlarged uterus. This weight gain often includes fat deposition, particularly around the hips, thighs, and buttocks, making the hips appear larger.
Fluid retention, also common during pregnancy, can lead to swelling throughout the body, including the hips and lower extremities, contributing to a wider appearance. The shift in a pregnant person’s center of gravity due to the growing abdomen can alter posture. An increased curvature in the lower back (lumbar lordosis) and an anterior pelvic tilt can make the hips appear to protrude more, creating the visual impression of increased width. These broader body shape changes are distinct from the hormonal effects on pelvic joints but collectively influence how the hip area is perceived.
Postpartum Pelvic Recovery
After childbirth, the body begins a gradual process of returning to its pre-pregnancy state, including the pelvis. Relaxin levels, elevated throughout pregnancy, decrease significantly after delivery, though they may remain higher for several months, particularly if breastfeeding. This reduction in relaxin allows the ligaments that softened during pregnancy to gradually tighten again.
The symphysis pubis and sacroiliac joints, which experienced increased mobility, slowly regain their stability. While the majority of hip widening reverses, some women notice a slight, subtle difference. Many women find their hips return substantially to their pre-pregnancy size, often by 70-80%, within 6 to 12 months postpartum. However, a small, permanent increase in hip width, 1-2 centimeters, can occur because the pelvic joints have stretched and may not fully return to their original position. The recovery timeline can vary greatly among individuals, with some feeling recovered within weeks and others taking up to 18 months or longer. Factors such as genetics, the degree of ligament laxity experienced, and subsequent pregnancies can influence the extent of this recovery.