Ovulation Induction and Uterine Motility Agents

Question 1

Bromocriptine

Answer 1

Non-peptide, orally effective
DA agonist. Inhibits PRL secretion.
Effective if hyper-PRL is cause (it inhibits Gn release)
Useful for some male infertility (caused by hyper-PRL)

Question 2

Clomiphene

Answer 2

Non-peptide, orally effective
Anti-estrogen –> blocks E feedback inhibition of Gn release
Gn release increases –> stim ovaries
Requires functional pituitary
Adverse: ovarian enlargement (estrogen agonist action), temporary hot flashes (E antagonist action)
Effective for Oligospermia in males

Question 3

Danazol

Answer 3

Non-peptide, orally effective
Weak androgen, some progestin/anti-E activities
Ovulation problem dt endometriosis
Androgen action: inhibits Gn secretion –> decrease E synthesis (–> relieve endometriosis)

Question 4

hCG

Answer 4

Peptide (pituitary defect)
Similar effects to LH (longer duration) 
Induce ovulation 
Treat male infertility 
Hypogonadism 
IM

Question 5

Menotropins

Answer 5

Peptide (pituitary defect) 
hMG
LH and FSH activity 
Used with hCG to induce ovulation 
Concerns: ovarian hyperstimulation, multiple births
Used in prep for in vitro fertilization 
Promote speratogenesis

Question 6

Gonadorelin

Answer 6

Peptide
Synthetic GnRH (used for hypothalamic defect)
Requires functional pituitary and ovaries
Pulsatile admin with infusion pump

Question 7

Oxytocin

Answer 7

Uterotonic agent
From posterior pituitary. Oxytocin-R = GPCR.
Selective stimulator of uterine smooth muscle contraction
Milk ejection from mammary glands
Constricts umbilical arteries/veins
Useful after delivery
High dose: relaxation of vascular smooth muscle
IV: uterine effects
Nasal spray: milk letdown
Use: during delivery (augmentation of labor, aggressive for induction of labor)
If give too much, use B2-adrenergic agonist to induce relaxation
Use after delivery: restore uterine tone, prevent hemorrhage (IV), breast feeding (nasal spray)

Question 8

Misoprostol

Answer 8

Uterotonic agent
Increase Ca++ and muscle contraction (GPCR): PG-E2/E1/F2alpha
Stimulate uterine contraction, induce cervical ripening (low dose), stimulate GI smooth muscle
PGE1 analog: less GI and fever
Use: prevent postpartum hemorrhage
Cheaper/easier than oxytocin
Oral or rectal
Pharmacological abortions: Used with mifepristone or methotrexate
Applied locally to induce cervical ripening
Excess PG’s mediate painful contractions

Question 9

Methylergonovine

Answer 9

Uterotonic agent (ergot alkyloid)

Question 10

Magnesium sulfate

Answer 10

Tocolytic agent (inhibit uterine motility)