Unformatted text preview: induce production of enzymes in the cervix that digest collagen (allowing for dilation). Increased cortisol (made by fetal adrenal gland) matures infant’s lungs (production of surfactants) In humans, corticotropin releasing hormone (CRH) made in the placenta (placental clock) causes the pituitary to secrete adrenocorticotropin (ACTH) into the fetal circulation. Values of maternal CRH in the 16-20 th weeks can predict delivery dates. Early increases lead to premature birth. ACTH causes the adrenals to produce cortisol which activates the placental enzymes to convert DHEA-S (dihydroxyepiandrosterone sulfate) into estrogen. Increased estrogen levels (and decreasing progesterone) from this process contribute to the actions mentioned above....
View Full Document
- Spring '09
- Physiology, progesterone, Uterus, estrogen levels