Sept6 M1,2-Contraception Flashcards
pearl index def
pregnancy rate after 1 year of exposure per 100 women years, using this method only
best methods of contraception
- sterilization (surgical)
- injection
- implants
- IUD
- OCP
- vaginal ring
common point between non surgical contraception methods with lowest pearl index
contain chemicals
why OCP has 98-99% efficacy
some individuals metabolize the steroids in the pill faster, shorter half life and may still get pregnant
very low nbr of people but till possible
OCP component and mech
E + P
- estrogens blocks hypoth and pit level release of LH and FSH (no LH surge + no FSH so follicle can’t become secondary antral) so block ovulation
- progestin affects ovary and prevents folliculogenesis, alters secretions of endometrial lining to make it thicker and harder for sperm to fertilize the egg
follicles seen and not seen when using OCP
- primordial present
- primary present
- antral ABSENT (bc still have LH, FSH, P and E but no LH surge). have less steroids in circulation
- no Graafian follicles
- REPRESSED FOLLICULOGENESIS*
endothelial lining in woman using OCP
- thinner bc no stim by steroids. lower steroids level than normal. + diminished blood loss (halved)
- endo not receptive for implantation
SEs of OCP
Are beneficial SEs
- repression of folliculogenesis bc of steroids (indep of FSH, LH)
- P makes repro tract more visquous, more protein secretions, thicker and harder for egg to move + prevents sperm from getting there
sx reduced with the OCP
- PMS
- menstrual cramps
- acne
- bleeding
- anemia
- ovarian cysts
- breast tenderness
why OCP helps reduce sx of menstrual cycle
bc no big surge in steroids
OCP reduces risk of what diseases
- ovarian, endometrial, GI and uterine cancer
- ovarian cysts
- PID
- iron deficiency anemia
- ectopic pregnancy
- fibrocystic breast disease
OCP SEs
- nausea
- breast tenderness
- mid cycle bleeding
- weight gain
- go away in 1-6 mo*
why imp to monitor OCP pt in first 3 months
risk of
- migraine headaches
- liver disease
- high BP
- gallbladder disease
- blood clots
does OCP cause breast cancer
no. if it does, risk increase is very low
absolute contraindications to OCP
- hx of breast ca
- hx of blood clots (if high dose OCP)
- liver, kidney dz
- unexplained uterine bleeding
- pregnancy
- smokers over 35
OCP is given how
- 3 weeks of E and P
- 1 week of nothing
emergency contraception works how
- smaller endometrium, not receptive for implantation, if fertilization has occured
- decrease in progestin after the effect of pill goes away causes the withdrawal bleed
how to use emergency contraception
within 72 hours of unprotected sex, use one or two doses to induce withdrawal bleed
effectiveness of emergency contraception
75-97%
ulipristal acetate is what
- drug used in morning after pill*
- selective progesterone R modulator.
- antag or agonist
- both work bc even if agonist, when effect goes away, P stops and get the menses
contraceptive patch haract
- no first pass effect
- replaced weekly
- steroids are lipophilic so easy abso
patch efficacy and compliance
- efficacy = or less than OCP (bc not weight adjusted)
- compliance >than OCP
options other than monthly bleed OCP
- continuous OCP with no monthly bleeds
- three-month cycle OCP
- one a year bleed OCP
- does no harm, no increase in cancer or complications*
E and P of OCP effect on HPO axis
- E blocks LH from rising + affects endo lining
- P blocks effect of E on cells
- they bind steroid binding proteins*
meds that reduce the half life of OCP (P and E)
drugs that induce the p450s in the liver and are metabolized by it. make the steroids metab faster
- rifampin (for TB)
- any drug blocking entero-hepatic circulation like Abx (kill bugs that prolong steroid half life)
goal of the morning pill
cause a menses
what happens when stop OCP
body readapts immediately. phase where follicle grows rapidly (secondary antral) can occur. menses immediately when stop
intrauterine devices rules
bigger and more nasty looking = works better
*larger surface area = lower pregnancy rate but higher bleeding rate
2 types of IUD
- with copper
- with progestin (Mirena for ex)
charact of copper IUDs and IUDs in general
- fertility returns as soon as removed
- copper = only working on ability of endo to receive blastocyst
- copper = cause 2x normal menstrual blood flow
contraindications to IUDs
- severe pain with periods (dysmenorrhea)
- copper allergy
- gono or chlam infection
- endometriosis or other current abnormal vaginal bleeding (bc copper IUD witll cause more blood less and pain in endometriosis)
- etc
progesterone IUD mech of action
- continuously stims endo to make proteins
- suppresses endometrial prolif (stim by estrogen Rs)
- blocks lymphocyte recruitments (which would help implantation)
progesterone vs copper IUD
less bleeding with P IUD
medicated vaginal ring is what
same principle as progesterone IUD but as a vaginal ring
contraceptive implant def
- injection of 6 tubes of silicone silastic polymer that are permeable to steroids (one used is progesterone)
- progesterone is released over 5 years
main problem with contraceptive implant
possible irregular bleeding or spotting (but no cycles per se).
-bleeding is also a problem of copper IUDs
contraindications to contraceptive implant (sustained progestin)
- liver disease
- breast cancer
- unexplained uterine bleeding (same contraindication as copper IUD)
- blood clots
immunocontraception for females is what
immunize a woman to the zona pellucida proteins (Zip-1), to GNRH LH or FSH, to sperm proteins and to bHCG
how vaccine against ZP would work
an antibody binds the ZP. this prevents the sperm from entering it
how vaccine against beta unit of HCG would work
- this unit is what makes it diff from FSH and LH (bc HCG, FSH and LH have the same alpha unit
- vaccine blocks HCG ability to rescue CL of pregnancy
immunocontraception success rates%
- to ZP = 75%
- to bHCG = 90-95% (reversible effect)
- to sperm proteins = 75%
hormonal male contraception groups what
injections, implants or creams of
- testo alone
- testo + P + E
- novel androgens
how male contraception works
want to keep the serum testo normal to block LH and FSH
what happens to serum testo if give testo only as male contraceptive
- low dose = not changing, normal
- interm dose = not changing, normal
- high dose = testo goes up
what happens to spermatogenesis if give testo only as male contraceptive
- low dose = working
- interm dose = not working (very low testo)
- high dose = working again
in testo only male contraception, why spermatogensis blocked at interm dose and works at high dose
- interm dose = testo suppresses LH secretion (axis) so Leydig cells prod of testo drops so less intragonadal testo
- high dose = even though Leydig cells suppressed, we’re giving enough testo exogenously to maintain spermatogenesis
effect of the testo + estrogen male contraception
- serum LH goes down
- serum testo increases transiently and back noral
- intragonadal testo goes down
charact of testo + estrogen male contraception
complete spermatogenesis is achieved if wait lng enough. + will take long to reverse the action
alternatives to testo in T and T+E male contraception
can use analogs that are more potent like MENT (10x more potent)
dimenthandrolone undecanoate is what
new male contraceptive that is both an androgen and progestin R agonist
non hormonal male contraception is what
- chemo (causes azoospermia)
- WIN18446 (inhibits enzyme in testis making retinoic acid into retinol (vitA). vitA is essential for spermatogenesis
- Gossypo (antispermatogenic effect via mt K+ channel suppression) bad SEs
- JQ1 (block hyperacetylation of histones necessary for sperm nucleus condensation)
- inhibitors of EDD maturation process
- other targets like proteins for fertilization, maturation in EDD, etc.
male contraception acting on inhibition of fertilizing ability of sperm and on EDD maturation
- EDD 5a reductase inhibitors (less testo in EDD = less sperm motility + binds egg less)
- nifedipine (CCB), blocks enzyme action for fertilization
- mifepristone (progesterone R on sperm necessary for sperm to enter egg)
- EPPIN (block EDD protease eppin, necessary for maturation)
immunocontraception in males
- nonexistent
- no research on it atm
