Contraception Flashcards
What is family planning?
Planning, provision and use of birth control
What is Marie Stopes?
Provides contraception and safe abortion
What is the UK MEC?
Used to choose safe contraception
What is category 1 in the UK MEC?
Can take every form of contraception
What is category 2?
When the advantages of using the method generally outweigh the theoretical or proven risks
What is category 3?
Where the theoretical or proven risks usually outweigh the advantages of the method.
What is category 4?
Represents an unacceptable health risk if method used
e.g. pill with history of blood clots
How do combined contraceptives work?
Suppress release of gonadotrophins which inhibits follicular development and prevents ovulation
How does progestogen in contraception help prevent ovulation/follicular development?
- Progestogen negative feedback decreases GnRH release
- This decreases FSH and LH
- Decreased levels of FSH inhibit follicular development, preventing an increase in oestradiol levels.
- Progestogen negative feedback and the lack of oestrogen positive feedback on LH release prevent a mid-cycle LH surge.
Inhibition of follicular development and the absence of a LH surge prevent ovulation.
What is mechanism of effect of oestrogen in combined contraceptive?
- Stabilises the endometrium and reduces the incidence of breakthrough bleeding
- Oestrogen negative feedback on the anterior pituitary greatly decreases the release of FSH, which inhibits follicular development and helps prevent ovulation.
How does progestogen in contraception prevent entry of sperm?
Decreasing amount of and increasing viscosity of cervical mucus (mucus plug)
Why can oral contraceptives increase blood clotting risk?
Oestrogen containing oral contraceptives increase the plasma concentration of clotting factors II, VII, X, XII, factor VIII, and fibrinogen
How does the Nuvraring combined ring work?
Vaginal ring is flexible and easy to insert and remove
The ring is worn for 3 weeks and discarded, and a new ring is inserted 1 week later (28 day cycle)
How does the use of the progesterone and combined pill differ?
Combined –> take for 21 days then 7 day break
Progesterone –> take for 28 days with no break, also tighter time frame
How does the progesterone only pill work?
Reduces endometrial receptivity (more than combined)
Suppresses ovulation (less than combined)
Can cause irregular bleeding
What are the progesterone only options?
- Oral
- Injection
- Implant
- IUS (coil)
How long does IUS last?
5 years
How does IUS work?
Progesterone effects (endometrial thinning and suppresses ovulation)
Reduces / stops period –> can be used to treat heavy periods
What is IUD? How does it differ from IUS?
IUD releases copper
IUS releases hormones
How does IUD work?
Copper prevents fertilisation by direct effect on sperm –> foreign body and causes endometrial changes
How. long does IUD work?
5-10 years
What are side effects of IUD?
Can cause heavy periods
What is male/female sterilisation?
Vasectomy
Tubal occlusion / ligation
What is a vasectomy?
Minor surgery to block sperm from reaching the semen that is ejaculated from the penis
Vas deferens are cut/tied/sealed
What is tubal occlusion?
A small metal coil was inserted into the fallopian tubes (via a catheter through the uterus). The body would respond to the coils by scarring over them.
What is tubal ligation?
Fallopian tubes are closed
How do emergency oral contraceptions work?
Delay ovulation through big dose of progesterone
What are other non-contraceptive benefits of contraception?
Reduction in risk of endometrial and ovarian cancers.
- 40% reduction.
- Related to endometrial effects and suppression of gonadotropins.
Decrease benign breast disease (fibrocystic and fibroadenoma).
Reduces iron-deficiency anaemia.
Treats pelvic pain caused by endometriosis.
What are risks of contraception?
Failure (Ectopic pregnancy)
Inconvenience.
Increased risk of clots / heart disease / stroke.
Pain during operative sterilisation / indwelling devices.
