amniotic sac

As the end of the pregnancy approaches, pelvic pain is often a signal of the start of labor. Labor pelvic pain is associated with pressure on the pelvis or the feeling that baby is getting heavier.

Testing for potential genetic problems typically requires piercing the abdomen and amniotic sac to collect a tissue sample from the fetus. Researchers in China may have found an alternative to invasive prenatal testing.

A caul (Latin: Caput galeatum, literally, "head helmet") is a thin, filmy membrane, the amnion, that can cover a newborn's head and face immediately after birth.