Final answer:
The AP diameter of the pelvic outlet averages about 11 centimeters in females and is wider to facilitate childbirth, with other features including a larger subpubic angle and a wider greater sciatic notch.
Step-by-step explanation:
The anteroposterior (AP) diameter of the pelvic outlet is an important measurement in the field of obstetrics. It refers to the distance between the lower margin of the pubic symphysis and the tip of the coccyx. This measurement averages about 11 centimeters in females; however, it can vary based on factors such as pelvic shape and size. The pelvic outlet is the inferior opening of the pelvis, and its shape is crucial for childbirth. The female pelvis typically features a wider distance at the pelvic outlet to accommodate the passage of a newborn, a larger subpubic angle, and a wider greater sciatic notch.