Contraceptives and Drugs acting on the Uterus Flashcards
the initial rise in _____ is what stimulates the ovarian follicles to developing (ripening of follicles)
FSH
the peak in ______ is responsible for the peak in LH/FSH and thus causes ovulation
estrogen
peak of ______ occurs slightly before ovulation
estrogen
peak of FSH/LH occurs during ovulation
what are two general approaches to prevent pregnancy?
- prevent ovulation (suppress LH/FSH release by preventing rise of estrogen levels)
- impair implantation (by maintaining elevated progesterone levels which why you give progestin)
the estrogen in combined oral contraceptives is either ethinyl estradiol or ______
mestranol
mestranol is a pro drug that is converted to ethinyl estradiol
which of the progestin oral contraceptives has anti androgenic effects
drospirenone
______ and ____ of the progestins have the highest androgenic activity
levonorgestrel and norgestrel
-norgestrel
most formation of OCP’s have 21 hormonally active pills and 7 placebo’s. what is the use of the placebos?
- facilitates consistent daily pill intake
- allows withdrawal from bleeding. has no benefit but its psychological for women to think that they have not completely wiped out their monthly bleeding
thickening of the cervical mucus and prevents sperm penetration is due to _____ (hormone)
progestin
also impairs implantation by induces changes in the endometrium
one term use of OCP’s is related to what AE
cardiovascular toxicity
when you first prescribe a patient OCP’s how would you advise the about the adverse effects?
they may experience symptoms of bloating nausea and breakthrough bleeding but should spontaneously resolve by the third cycle
the most common adverse effect of OCP’s is _______
breakthrough bleeding caused by the low dose estrogen because estrogen is used to stabilize the endometrium
women who develop migraine WHILE taking OCP’s should _____
stop taking OCP’s; okay to take them if they had migraines before taking OCP’s
why are cardiovascular disorders an AE of OCP’s?
- estrogens ↑ the production f factor VII, X and fibrinogen → ↑ risk of thromboembolic events
a patient on OCP’s and taking antibacterial can _____ estrogen levels
↓; ethinyl estradiol is conjugated in ht liver and excreted into the bile, hydrolyzed by intestinal bacterial and reabsorbed as an active drug. if antibiotics reduce the population of intestinal bacterial, that can interrupt the enterohepatic circulation of estrogen
________ (antibiotic) has substantial evidence that it substantially lowers steroid levels
rifampin
can you give OCP’s to patients who are older than 35 and smokes more than 15 cigarettes per day:
NO;
however you can give them to someone who is over 35 OR if a person smokes more than 15 cigarettes per day
you cannot give OCP’s to patients with migraines with aura because there is ↑ risk of ______
cerebrovascular events
unscheduled bleeding and spotting are more common in what oral therapy for OCP’s (combined or progestin only)
progestin only therapy however this method had NO RISK of thromboembolic events
what is depo-provera? how does it work to prevent pregnancy
it is a progestin only injectable contraceptive and contains DMPA (depot medroxyprogesterone acetate) and is extremely effective because in this case, the progestin levels are high enough to prevent ovulation via negative feedback
what are some adverse effects of depo-provera?
- high incidence of menstrual irregularities and weight gain
- SIGNIFICANT loss of bone mineral density with chronic use
the major adverse effect of progestin implants is ______
irregular menstrual bleeding
the intrauterine systems release ______ (drug)
levonorgestrel (progestin); effective for 5 years
Plan B contains tablets of _______
levonorgestrel (progestin)
1st one takin within 72 hours of sex and 2nd is taken 12 hours later
in order to reduce the rate of failed induction and for oxytocin to work properly, cervical ripening must occur. Drugs used for cervical ripening include _____ and ______
prostaglandins: dinoprostone and misoprostol
what is the use of dinoprostone and misoprostol?
they ripen the cervix and also stimulate uterine contractions (no need for oxytocin)
dinoprostone is a ______ analog
PGE2
misoprostol is a _____ analog
PGE1
which of the prostaglandins can be administered orally or sublingually
misoprostol
oxytocin works by ____ protein couple receptors
Gq; activates MLCK and
↑ prostaglandin synthesis (why oxytocin can be used for post partum hemorrhage
high concentrations oxytocin can activate ________ receptor and cause _______
vasopressin receptors and cause excessive fluid retention, hyponatremia, HF, seizures and death
ergot alkaloids (methylergonovine) can be given for _____. what is its MOA
post partum hemorrhage
partial agonist at α adrenergic receptors and some serotonin receptors
tocolytics are given to ________. give examples of some
relax the uterus and delay labor
magnesium sulfate, indomethacin, nifedipine
magnesium sulfate is a _______ agent and inhibits cellular action potentials by _______
tocolytic agent that uncles excitation-contraction in myometrial cells through inhibition of action potentials
_______ is the main NSAID that is used to speed up/delay labor
Indomethacin; delay labor because prostaglandins stimulate uterine contractions
an AE of ______ is that it CAN cross the placenta and lead to respiratory and motor depression of the neonate
magnesium sulfate
premature closure or constriction of the ductus arteriosus is an AE of _______________
indomethacin (NSAID given to delay labor)
indomethacin should be given during what period of gestation?
given BEFORE 32 weeks gestation because after, there is ↑ chance of premature closure of the ductus arteriosus
which tocolytic agent is a calcium channel blocker?
nifedipine; associate with more frequent successful prolongation of pregnancy
what are the three abortifacients
- mifepristone (anti progestin)
- misoprostol (prostaglandin analog)
- methotrexate (folic acid antagonist)
