Which hip should a pillow be placed under for a pregnant woman in her 2nd or 3rd trimester?

Placing a pillow under the right hip of a pregnant woman in her 2nd or 3rd trimester is recommended primarily to improve blood circulation and provide comfort. The rationale for this positioning relates to the anatomical structures and physiological changes during pregnancy.

When a pregnant woman lies on her side, especially in the left lateral position, it helps optimize blood flow to the fetus and the mother's organs. However, placing a pillow under the right hip can help support the body’s alignment, reducing strain on the lower back and hips. This position also alleviates pressure on the vena cava, a major vein responsible for returning blood to the heart. Proper positioning can significantly improve comfort levels for the mother, allowing for better relaxation, which is important during the later stages of pregnancy.

It's worth noting that while the focus is on the right hip in this context, the practice often encourages the left lateral position, which is ideal. However, there are cases when slight adjustments like supporting the right hip can provide necessary comfort when lying on the left side. Therefore, the correct approach enhances both maternal comfort and fetal well-being.