The four types of pelvis are gynoid, android, anthropoid, and platypelloid. These classifications were defined by Caldwell and Moloy based on the shape of the pelvic inlet.
Types of Pelvis
Caldwell and Moloy classified the female pelvis into four main types, each with distinct characteristics that can influence childbirth. The reference examined a study of 147 cases to determine the prevalence of each type. Here's a breakdown:
-
Gynoid: This is considered the "typical female" pelvis.
- It is round and has wide diameters.
- It is the most favorable for vaginal delivery.
- According to the reference, the gynoid pelvis accounts for approximately 41.4% of the population studied.
-
Android: This pelvis is heart-shaped and resembles a typical male pelvis.
- It has a narrow and deep structure.
- It is less favorable for vaginal delivery.
- The reference indicates that around 32.5% of the population studied had an android pelvis.
-
Anthropoid: This pelvis is oval-shaped, with a longer anteroposterior diameter.
- It can sometimes accommodate vaginal delivery, though the baby may be born in an occiput posterior position.
- The study reported that approximately 23.5% of the population had this type of pelvis.
-
Platypelloid: This pelvis is flattened, with a wide transverse diameter but a short anteroposterior diameter.
- It is the least common type.
- It is generally unfavorable for vaginal delivery.
- The reference shows it occurs in only about 2.6% of the population studied.
| Pelvis Type | Shape | Prevalence (%) | Favorability for Vaginal Delivery |
|---|---|---|---|
| Gynoid | Round | 41.4 | Most favorable |
| Android | Heart-shaped | 32.5 | Less favorable |
| Anthropoid | Oval | 23.5 | Sometimes favorable |
| Platypelloid | Flattened (oval) | 2.6 | Least favorable |
