Contraception and HRT Flashcards
List 3 ways by which contraception prevents pregnancy.
1 - Preventing ovulation.
2 - Preventing fertilisation.
3 - Preventing implantation.
Which event marks the beginning of pregnancy?
Implantation.
What is the PEARL index?
The failure rate of a contraceptive per 100 years of use.
List 4 contraceptives with no potential for user failure.
1 - Intrauterine devices such as copper coils.
2 - Intrauterine systems such as levonorgestrel.
3 - Hormone implants.
4 - Sterilisation.
List 3 contraceptives with potential for user failure.
1 - Barrier contraceptives.
2 - Hormonal drugs.
3 - Lactational amenorrhoea.
How do levels of oestrogen and progesterone differ between pregnancy and the combined contraceptive pill?
- In pregnancy, oestrogen and progesterone increase until delivery.
- With the combined pill, oestrogen and progesterone stay at a constant level.
What is the typical failure rate of male condoms?
How does this compare to the failure rate with perfect use?
- Male condoms have a 17% failure rate with typical use.
- Male condoms have a 2% failure rate with perfect use.
What is the typical failure rate of female condoms?
How does this compare to the failure rate with perfect use?
- Female condoms have a 21% failure rate with typical use.
- Female condoms have a 5% failure rate with perfect use.
List 2 barrier methods other than condoms.
How are they used?
1 - Diaphragms.
2 - Caps.
- They are inserted into the cervix and used in combination with spermicides.
What does LARC stand for?
List 4 advantages of LARCs.
- Long-acting reversible contraception.
1 - Effectiveness doesn’t depend on memory or use.
2 - More effective than other forms of contraception.
3 - Cost-effective.
List 4 LARCs.
1 - Intrauterine systems.
2 - Intrauterine devices.
3 - Implants.
4 - Progesterone only injection.
What are intrauterine systems?
Describe the mechanism of action of intrauterine systems.
- Intrauterine systems are small, plastic T-shaped devices that are inserted into the uterus.
- They gradually release levonorgestrel, a progesterone analogue. This causes:
1 - Thinning of the endometrium.
2 - Thickening of the cervical mucus.
3 - Inhibition of ovulation by negative feedback of FSH and LH.
What is the failure rate of intrauterine systems?
<1%.
What are intrauterine devices?
Describe the mechanism of action of intrauterine devices.
- Intrauterine devices are small, plastic T-shaped devices with copper on the stem / arms that are inserted into the uterus.
- They are directly toxic to both the sperm and the egg.
- If fertilisation occurs, they prevent implantation by inducing a foreign body reaction.
What is the failure rate of intrauterine systems?
<1%.
Describe the mechanism of action of implants.
They release etonogestrel, a progesterone analogue, to:
1 - Prevent ovulation by negative feedback of FSH and LH.
2 - Thicken cervical mucus.
What is the failure rate of implants?
<1%.
What is the main injectable contraceptive?
Which drug does it contain?
- Depo-provera is the main injectable contraceptive.
- It contains medroxyprogesterone acetate, a progesterone analogue.
List 2 injectable contraceptives other than Depo-provera.
1 - Sayana Press.
2 - Norethisterone enanthate.
List 3 combined hormonal contraceptives.
1 - Combined pill.
2 - Patch.
3 - Vaginal ring.
List the mechanisms of action by which hormonal contraceptives prevent pregnancy.
- Primary mechanism: prevent ovulation by negative feedback of FSH and LH.
- Secondary mechanism: thickens cervical mucus and thins endometrium.
Which hormones are contained in combined pills?
Oestrogen and progesterone.
What is a hormone-free gap?
The period in which a person taking a combined pill stops taking the medication to allow for withdrawal bleeding.
List the drugs contained in combined vaginal rings.
1 - An oestrogen analogue.
2 - Etonogestrel, a progesterone analogue.
List 3 examples of progesterone only pills.
1 - Desogestrel.
2 - Levonorgestrel.
3 - Norethisterone.
*All of these are progesterone analogues.
Describe the mechanism of action of progesterone only pills.
- Primary mechanism: prevent ovulation by negative feedback of FSH and LH.
- Secondary mechanism: thicken cervical mucus and thin endometrium.
List 3 main fertility indicators.
1 - Body temperature.
2 - Consistency and colour of cervical secretions.
3 - Point in menstrual cycle.
List 2 natural family planning methods.
1 - Using indicators to determine fertility at a particular point in the menstrual cycle.
2 - Lactational amenorrhoea.
What is the failure rate of using the 3 main fertility indicators to determine fertility as a contraceptive method?
1 - 20%.
What is the failure rate of using lactational amenorrhoea as a contraceptive method?
2%.
How do vasectomies work?
What is the failure rate of vasectomies?
- By cutting and sealing / tying the vas deferens, preventing the sperm from entering the prostate.
- Failure rate is 1 in 2000.
How does female sterilisation work?
- By clipping the uterine tubes or by a salpingectomy, where a part of the uterine tube is removed and the open ends are tied together.
- Failure rate is 1 in 200.
List 2 emergency contraceptives.
How long after sex are the contraceptives effective?
1 - Copper coil intrauterine device (effective for 120 hours after).
2 - Emergency contraceptive pills such as levonorgestrel (effective for 96 hours after) or ulipristal acetate (effective for 120 hours after).
What is the failure rate for the copper coil as an emergency contraceptive?
<1%.
What is the failure rate for emergency contraceptive pills?
- 40% for levonorgestrel.
- 20 - 40% for ulipristal acetate.
In women with premature ovarian insufficiency, when does menopause occur?
Before the age of 40.
List 2 forms of hormone replacement therapy for treatment of symptoms of menopause.
- In a woman with a uterus, offer combined oestrogen + progesterone.
- In a woman without a uterus, offer oestrogen.
- Symptoms of menopause are on other lectures.
