Content of luteinizing hormone-releasing factor in the human placenta.

Immunoreactive luteinizing hormone-releasing factor (LRF) was quantitated in the human placenta. It was found that the total placental content as well as the content per milligram of placental tissue varied with the stages of gestation. The fetal sex did not affect the LRF production. These studies establish that the placenta contains large amounts of LRF, immunologically identical to hypothalamic LRF.