WEEK 5: CONTRACEPTION Flashcards
What are contraceptives?
Devices used to prevent pregnancy
What are the mostly used contraceptive methods?
Female sterilization & IUD: the most common methods used (19% and 14% in 2015).
Outline considerations in Choosing Birth Control Method
*Effectiveness–statistics show two numbers:
-Failure rate: # of women per 100 who become pregnant after 1 yr. when using a birth control consistently & correctly
-Typical use failure rate–takes into account improper or inconsistent use
About half of all unintended pregnancies occur among women using contraceptives
*Cost
*Ease of use
*Side effects
*Parity and age
Outline how to rule-out pregnancy reasonably before prescribing contraceptives.
1.Menstrual period started in the past 5 days?
2.Gave birth in the past 4 weeks
3.Breastfeeding, gave birth less than 6 months ago, period have not returned?
4.Had miscarriage or abortion in the past 7 days.
5.No sex since your last period
6.Been using another method correctly.
State the 4 types of birth control methods.
*Hormone based
*Barrier & spermicide methods
*Surgical
*Natural based methods
Outline the hormonal based contraceptives.
*Combined contraceptives: estrogen & progestin(binds to progesterone receptors)
-Oral Contraceptives (COCs)
-Injectable contraceptives (CICs)
-Transdermal patch-to be changed weekly
-Vaginal ring-to be inserted and left for three weeks
*Progesterone-only contraceptives:
-Long-acting/Progestin-only- implant & IUD
-Low dose/progestin-only (Mini pill)
Describe the 3 ways in hormonal contraceptives prevent pregnancy.
What is the percentage effectiveness of hormonal contraceptives?
*Estrogen & progesterone in hormonal contraceptives
inhibit LH, FSH, and GnRH secretion, preventing ovulation.
*Progesterone also:
*thickens cervical mucus to prevent
Passage of sperm into the uterus
*changes uterine lining to inhibit implantation
*97% to 99%
Outline the benefits of hormonal contraceptives.
Benefits of hormonal contraceptives:
*Reliable, reversible and effective contraceptive (97-99%)
*To treatmenorrhagiaordysmenorrhea (decreases endometrial proliferation): e.g., for women with polycystic ovary syndrome.
*With longer duration of use decreases the risk of endometrial cancer-same mechanism!
*Decreases the risk of development of ovarian cancer-greatest for longer duration of use (reducing the lifetime number of ovulations).
*To treat hyperandrogenism (e.g., reduce the severity of acne)-decrease gonadotropin stimulation of androgen production by the ovary.
Outline adverse effects of hormonal contraceptives.
*Cardiovascular disorders (CVD)-rare among young women; pregnancy itself increase the risk of CVD, and promotes thrombosis (primarily an effect of estrogen):
-Venous thromboembolism/VTE
-Arterial thromboembolism: Myocardial infarction or Stroke, especially among older women who smoke.
*Breast Cancer (BCA):
-Estrogen containing contraceptives might increase the risk of BCA.
-Most BCA are diagnosed in post-menopausal women.
Describe how the progestin only contraceptives MOA.
*Progestin-only injectable
*Implantable rods, and
*Progestin releasing Intra uterine Device (IUD
1.Progestin only injectable
Given by injection into the muscle (intramuscular injection). The hormone is then released slowly into the bloodstream.
EXAMPLES:
*Depo povera/Depot medroxyprogesterone acetate (DMPA)-quarterly,
*Norethisterone enanthate (NET-EN)- every two month
- 1.5” rod is inserted under skin of upper arm
Progestin-only
3.Intrauterine Devices (IUDs)
*Small plastic objects inserted into uterus:
2 types:
*Hormone-releasing (progesterone)~ 5 years
*Copper-releasing ~10 years
Have fine plastic threads attached that hang slightly out of cervix into vagina for removal.
4.Low dose progesterone/progestin-only pills (POP)/Mini-pills:
*Work primarily by the thickening cervical mucous.
Useful for women wanting to avoid estrogen or lactating.
*Should be taken at the same time each day to ensure sufficient plasma level of progestin to alter cervical mucous.
5.Emergency Contraceptive Pills (ECPs)/Morning after pills/post-coital contraceptives.
*ECPs-should be taken within 5 days after unprotected sex;
*Primarily work by preventing or delaying ovulation;
*Progestin-only or a progestin &estrogen combination.
Special dedicated ECP product: with levonorgestrel only, or estrogen and levonorgestrel combined, or ulipristal acetate.
-Progestin-only pills: with levonorgestrel or norgestrel;
-Combined oral contraceptives: with estrogen (ethinyl estradiol ) and a progestin: levonorgestrel, norgestrel, or norethindrone (also called norethisterone)
How do barrier methods and spermicides work?
List their examples.
Work by preventing sperm from reaching an egg.
*Condoms: male & female.
*Spermicides: foam/sponge.
*Cervical barriers: diaphragm & cervical cap.
Describe how the cervical barrier devices are used and their MOA.
1.Condoms: trap semen.
2.Spermicide:
- Chemical that kills sperm (nonoxynol-9)
Different forms: foam, sponge, suppositories, creams, film
*Use shortly before sex; mostly used with diaphragm and cervical cap.
*Not effective enough to be used w/o a condom or other method.
3.Cervical barrier devices.
*Cervical cap: covers cervix only
*Diaphragm: covers upper vaginal wall, too.
Method is usually combined w/spermicide.
Describe the surgical methods of birth control.
1.Female Sterilization/tubal sterilization/ligation
*Permanent method-works by preventing eggs released from the ovaries meeting the sperm;
Involves a physical examination and surgery (Mini laparotomy or Laparoscopy)-the procedure is done by a specifically trained provider.
2.Vasectomy/Male sterilization/surgical contraception- permanent method
*Works by closing off each vas deferens-semen is ejaculated, but it cannot cause pregnancy;
*Through a puncture or small incision in the scrotum, the provider locates each of the 2 tubes that carries sperm to the penis (vas deferens) and cuts or blocks it by cutting and tying it closed, or by applying heat or electricity (cautery);
Vasectomy is not fully effective for 3 months after the procedure.
Describe the natural methods, “Fertility Awareness.”
Works by keeping sperm out of vagina near ovulation
1) Standard days method (Cycle beads)
*For women w/cycles between 26 & 32 days
Couples avoid unprotected intercourse b/n days 8-19 of each menstrual cycle
*Effective natural family planning methods
2) Mucus method: based on cyclical changes
*Vaginal secretions change throughout cycle; woman learns to “read” these changes and keeps a daily chart
3) Calendar method: self- knowledge of fertility
After charting cycles for some time (preferably 1 year), a woman estimates the time she is ovulating based on the calendar.
4) Basal body-temperature
*Based on changes in body temperature around ovulation
*Slight drop immediately before ovulation (approximately 3 days before ovulation)
*After ovulation, release of progesterone causes slight increase in temperature (0.2 degrees Celsius)
*Fertile- until 3 days after a sustained temp. increase
5) Lactational Amenorrhea (LAM): exclusive BF 6 Ms a/r birth
*The lactationalamenorrheamethod (LAM) works on the basis that exclusive breast-feeding suppresses a woman’s fertility, preventing pregnancy while she is caring for a young infant.
*The baby’s sucking causes a mother’s uterus to contract and reduces the flow of blood after delivery
*During lactation, menstruation ceases, offering a form of contraception.
Often, some combination of these methods will be used
State the advantages of using natural methods.
Pros:
*Essentially free
*No medical side effects
*Does not interrupt sexual activity
*Woman gains awareness about her body and natural cycles, which can increase comfort w/sexuality
