Contraception Flashcards
The menstrual cycle is regulated by
positive and negative feedback in the hypothalamic–pituitary–ovarian axis.
Gonadotropin-releasing hormone (GnRH) pulses regulate
follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which in turn, regulate the secretion of estrogen and progesterone from the ovary
The menstrual cycle is divided into
four phases: follicular, ovulatory, luteal, and menstrual.
Follicular phase: FSH stimulates
several follicles to develop
several follicles to develop
estradiol to create negative feedback and decrease FSH levels.
Ovulatory phase: estradiol levels peak
and exert positive feedback to induce an LH surge, which facilitates release of the mature ovum.
Estrogen promotes proliferation
of the endometrium and development of progesterone receptors in the endometrium.
Luteal phase:
progesterone prevents new follicle development as well as differentiation of the endometrium.
If no pregnancy, the
corpus luteum degenerates, leading to menstrual bleeding.
Use the safest, best-tolerated, and most
effective method that the patient desires.
Safety
Tolerance
Effectiveness
Rational Drug Selection
Start with absolute contraindications.
Delivery method should be of patient’s choice.
Fine tune based on:
Menstrual pattern
Side-effect profile
Consider:
Patient’s desire for discretion
Timing of subsequent pregnancy
Steps in choice and initiation
establish rapport
identify those appropriate to receive contraceptive
counseling
assess medical history and contraindication to methods
initiate contraceptive
counseling process
elicit informed preferences for method characteristics
facilitate preference-
concordant decision making
counsel about method initiation and use
World Health Organization Medical Eligibility Criteria for Contraception Use
US Medical Eligibility Criteria for Conception Use
Provide definitive guidance on safety across a broad range of conditions for different patient populations
Both label contraceptive methods as
category 1, 2, 3, or 4 for each identified condition
Categories 1 and 2 are considered
generally safe
Category 4 methods are
contraindicated
For those classified as category 3,
the recommendations state that the “method is usually not recommended unless other more appropriate methods are not available or acceptable.”
Contraception Methods
Combined hormonal contraceptives
Progestin-only contraceptives
Intrauterine devices
Emergency contraceptive pills
Estrogen has positive effects on
bone mass, increases serum triglycerides, and improves ratio of high-density lipoprotein to low-density lipoprotein.
Estrogen stimulates
coagulation and fibrinolyticpathways
Progesterone increases
body temperature and insulin levels.
Progesterone may depress
the central nervous system
Two formulations of estrogen are available in contraceptive
ethinyl estradiol and mestranol
Progestins are primarily responsible
for the contraceptive effect.
Progestins exhibit a
egative effect in the hypothalamic-pituitary-ovarian axis.
Progestins cause atrophy
of the endometrium, preventing implantation.
The estrogen component improves
efficacy by suppressing FSH release.
Estrogen provides
cycle control
Traditional
21 days active drug + 7 days inactive tablets with withdrawal bleed during inactive tablets
Extended cycle
84 days of active drug, then 7 days off
Withdrawal bleed once every 3 months
Monophasic: same dose
of estrogen and progestin for full cycle
Biphasic: vary
the dose of progestin
Triphasic: vary the dose
of estrogen, progestin, or both
Ortho Evra patch: releases
20 mcg of estrogen and 150 mcg of norelgestromin
Patch applied weekly
for 3 weeks, then 1 week off
start patch on
on first day of menses
Can start other days if back up method is used
Topical Patch ADR
ADRs similar to OC ADRs
Topical Patch increased
failure rate in women weighing more than 198 lb
NuvaRing is a
a soft, flexible plastic ring that releases 15 mcg of estrogen and 120 mcg of etonogestrel daily.
Ring is placed in the
vagina, left in place for 3 weeks, and then is left off for 1 week.
ring has better
Better cycle control and decreased breakthrough bleeding are achieved compared with OC.
ring systemic exposure
Systemic exposure to estrogen is lower.
Progestin-Only Pills - these are used when
These are used when estrogen is contraindicated
Progestin-Only Pills effeict is through
Contraceptive effect is through thickening of cervical mucus and prevention of sperm penetration.
Progestin-Only Pills useres have to be diligent
Users have to be diligent about taking dose daily at the same time.
If a pill is taken even a few hours late, a back-up method is recommended for the following 48 hours
Progestin-Only Pills ADR
ADRs: changing bleeding patterns and breast tenderness are common.
Depot medroxyprogesterone acetate (Depo-Provera) is a
long-acting, injectable progestin-only contraceptive.
Depot - One injection
One injection is effective in suppressing ovulation for 12 to 13 weeks
Depot Advantages
Once every 12 week dosing
Effective
Depot - Disadvantages
Spotting, followed by amenorrhea
Weight gain
Depression
Black Box warning: decreased bone density with longer-term use
