Contracted pelvis is a medical term used to describe an abnormal narrowing of the pelvic opening. This condition is common among women and can make vaginal delivery during childbirth challenging or even impossible.

The female pelvis is designed to accommodate the passage of a baby during delivery. The pelvic bones form a ring-like structure that includes the sacrum and the two hip bones. A contracted pelvis happens when the ring of the pelvis is smaller than usual, making it difficult for the baby to pass through.

There are different types of contracted pelvis, including:

1. Android Pelvis: This is a funneled-shaped pelvis. The bones of the pelvic brim are narrow and heart-shaped, with a small outlet.

2. Anthropoid Pelvis: This type of pelvis is oval-shaped and is more common among women of African descent.

3. Gynecoid Pelvis: This is the most common type of pelvis and is shaped like a rounded bowl. It is more favorable for vaginal delivery.

4. Platypelloid Pelvis: This type of pelvis is flatter than the gynecoid pelvis and is less favorable for vaginal delivery.

Doctors often diagnose contracted pelvis during pregnancy, using a combination of medical imaging, physical examinations, and previous birth experiences. A contracted pelvis can cause difficulties during labor, such as slow progress, prolonged labor, and fetal distress. In severe cases, it may require a cesarean section to deliver the baby safely.

Some of the common causes of contracted pelvis among women include genetic factors, malnutrition, rickets, and pelvic fractures. In some cases, contracting pelvic muscles, such as those that occur during spina bifida, can lead to pelvic contraction.

In conclusion, contracting pelvis is a medical condition that can make childbirth challenging or impossible. It is important for expectant mothers to discuss any concerns about their pelvis with their healthcare provider. With proper care, most women with contracted pelvis can deliver the baby safely and have a successful childbirth experience.