Final answer:
Abnormalities of the pelvic structure for labor involve variations in the shape and size of the pelvis. Different types of pelvis, such as gynecoid, android, anthropoid, and platypelloid, can affect the progress of labor.
Step-by-step explanation:
The abnormalities of the pelvic structure for labor mainly involve variations in the shape and size of the pelvis. The different types of pelvis are classified based on the shape of the pelvic inlet and outlet, as well as the dimensions of the pelvic cavity. Some common abnormalities include:
- Gynecoid pelvis: This is the typical female pelvis shape, which is adapted for childbirth due to its rounder pelvic brim, wider pelvic cavity, and larger subpubic angle.
- Android pelvis: This is a more masculine pelvis shape, with a heart-shaped pelvic inlet and narrower pelvic cavity. It may restrict the passage of the baby during labor.
- Anthropoid pelvis: This pelvis shape is characterized by a narrower, longer pelvic cavity and an oval-shaped pelvic inlet. It may require adjustments in labor positions.
- Platypelloid pelvis: This rare pelvis shape has a flat pelvic brim and a wider transverse diameter. It can lead to difficulties in delivering the baby's head.