Maternal Physio - Endo Flashcards
T/F. Pituitary gland enlarges during pregnancy
Enlarges by approximately 135%
T/F. Growth hormone is essential for maintenance of pregnancy
False; GH is not essential for maintenance of pregnancy
Source of GH
- First trimester
- At 17 weeks AOG
- First trimester
- Secreted predominantly from maternal pituitary gland
- At 17 weeks AOG
- Placenta (syncitiotrophoblast) is the principal source
T/F. Fetal growth progresses in the complete absence of placental GH
True
Is prolactin production increased or decreased during pregnancy?
Increased; estrogen stimulation increases the number of APG lactotrophs
Hormone that inhibits prolactin secretion
Dopamine
Memory aid:
-
DOPamine
- Dopamine
- Oppresses
- Prolactin
Prevent water transfer from fetus into the maternal compartment to prevent fetal dehydration
- Hormone
- Produced by
- Hormone
- Prolactin in amniotic fluid
- Produced by
- Uterine decidua
What happens to thyroid hormone production? What is the mechanism?
- Increased by 40 to 100% to meet maternal and fetal needs
- In response to high estrogen levels, pregnant women have elevated TBG and therefore will have elevated total thyroxine and T3
What happens to thyroid-releasing hormone in pregnancy?
- Not increased
- Crosses the placenta and may stimulate the fetal pituitary to secrete thyrotropin
PTH level in pregnancy
↓ in first trimester but then rise progressively the remainder of the pregnancy
Effect of estrogen in PTH and consequence
Estrogens block the action of parathyroid hormone on bone resorption, resulting in ↑ hormone levels, which allow the fetus to have adequate calcium supply
Allows for bone deposition in fetus
The fetus has ↑ calcitonin levels
Increased adrenal gland secretion
- Cortisol
- Aldosterone
- Deoxycortisone
- Androstenedione
- Testosterone
Decreased adrenal gland secretion
DHEA-S
- Memory aid:*
- DHEAcreased
