Pregnancy and Childbirth
In later stages of pregnancy the fetus's head aligns inside the pelvis. Also joints of bones soften due to the effect of pregnancy hormones. These factors may cause pelvic joint pain (Symphysis Pubis Dysfunction or SPD). As the end of pregnancy approaches, the ligaments of the sacroiliac joint loosen, letting the pelvis outlet widen somewhat; this is easily noticeable in the cow.
During childbirth (unless by Cesarean section) the fetus passes through the maternal pelvic opening.
Read more about this topic: Human Pelvis
Famous quotes containing the words pregnancy and/or childbirth:
“There are highly gifted spirits who are always infertile simply because, owing to a weakness in temperament, they are too impatient to wait out their pregnancy to term.”
—Friedrich Nietzsche (1844–1900)
“We in the West do not refrain from childbirth because we are concerned about the population explosion or because we feel we cannot afford children, but because we do not like children.”
—Germaine Greer (b. 1939)