Uterine activty and plasma progesterone levels in pregnant goats

Uterine activity was recorded during the last few weeks of pregnacy in goats, and related to changes in plasma progesterone concentration. In six of the 14 pregnancies, there was little activity until immediately pre-partum, but the remainder showed a progressive increase in uterine motility, particularly during the last seven days of pregnancy. There was a significant correlation between increased uterine activity and decline of peripheral plasma progesterone levels.