luteoplacental shift

lu·te·o·pla·cen·tal shift

the change in site of production of the estrogen and progesterone essential for human pregnancy from the corpus luteum to the placenta; ovariectomy always terminates pregnancy in most mammals because their placentas never produce enough estrogen and progesterone, but, after the sixth week of pregnancy, a human placenta can produce enough of these hormones to prevent abortion despite ovariectomy.

lu·te·o·pla·cen·tal shift

(lū'tē-ō-plă-sen'tăl shift)
The change in site of production of the estrogen and progesterone essential for human pregnancy from the corpus luteum to the placenta; after the sixth week of pregnancy, a human placenta can produce enough of these hormones to prevent abortion despite ovariectomy.