Flashcards in Repro 7.2 contraception and infertility Deck (73)
What is the effect of low levels of oestrogen?
Negative feedback onto the hypothalamus and the anterior pituatory, reduces levels of LH.
What is the effect of high levels of oestrogen at ovulation?
There's no progesterone so oestrogen leads to positive feedback on the hypothalamus and the pituatory, leading to the LH surge.
What is the effect of high/moderate doses of progesterone?
Promote the negative effects of oestrogen, leading to no LH surge, therefore no ovulation.
What is the effect of low levels of progesterone?
wont inhibit the LH surge, but does thicken the cervical mucus, making the environement hostile towards sperm.
What are some common methods of contraception?
(What part of the reproductive tract are you targetting?
-prevention of ovulation
-inhibition of sperm transport
-inhibition of implantation
Describe natural methods of contraception.
getting to know your cycle so you know when you'll be ovulating, then not having intercourse just before/during that time.
Using your temperature, which increases slightly when progesterone is high, to montior the point of your cycle.
After childbirth, breastfeeding leads to increased prolactin release, which inhibits GnRH release, so you do not ovulate.
What are some advantages of natural methods of contraception?
dont have to use hormones/chemicals
What are some disadvantages of natural methods of contraception?
Rely on really regular menstruation, which cant always be predictable.
no as effective, eg when stressed, or if you lose weight your cycles may not follow thier regular pattern.
Describe barrier contraception.
Phyical barrier stopping sperm from getting into the female reproductive tract, eg condom. Diaphragm.
Diaphragm may alos be sprayed with spermicide before fitting, so there is a chemical barrier to stop sperm too.
What are some advantages of barrier contraception?
-protects against STIs
-No use of hormones
-can be inserted at any point before intercourse.
What are some disadvantages of barrier contraception?
-Male condoms- some allergic to latex, can tear/come off.
-female condoms- not widely available.
-diaphragm- can displace. spermicide may cause local reactions.
What are some contraceptive methods of preventing ovulation?
Describe the COCP
Uses high levels of progestogen and oestrogen to inhibit ovulation.
The progestogen also has secondary effects of thickening cervical mucus, and reducing the endometrial receptivity so implantation is less likely.
What are some advantages of COCP?
-other uses for skin, releiving menstrual disorders.
-regulates menstrual cycle really well
-reduces the risk of ovarian cancer and cysts.
What are some disadvantages of the COCP?
-have to remember to take it at the same time every day
-can get breakthrough bleeding, breast tenderness, mood swings etc.
-Increases the risk of thromboembolism, cant be used for people who get migranes, etc.
-many contraindications. (PRevious MI, TIA, etc)
What is the synthetic progesterone called?
What is the progesterone depot?
Intramuscular injection into the buttocks to inhibit ovulation via high levels of prgestegon.
(also thickens cervical mucus and decreases receptivity of the endometrium).
What are some advantages of the progesterone depot?
-it lasts 3 months (Can forget about it after that)-convenient
-can relieve menstrual disorders.
What are some disadvantages of the progesterone depot?
-doesnt protect agaisnt STIs
-can cause irregular altered bleeding.
-after use, fertility can take up to 1 year to return (Not easily reversible)
-small loss of mineral bone density
What is the progesterone implant?
A small plastic rod which contains progesterone and is inserted under the skin of the inner arm, which releases high levels of progesterone, inhibiting ovulation.
(thickened cervical mucus, decreases endometrial receptivity)
What are some advantages of the progesterone implant?
-long duration of action (3 years)
-can be used to relieve menstrual disorders.
What are some disadvantages of the progesterone implant?
-requires a small procedure to fit and remove it.
-can cause irregular bleeding
-can cause local adverse effects.
What is the main contraception that causes inhibition of sperm transport?
The progesterone only pill.
How does the progesterone only pill work?
Low levels of progesterone which causes thickening of the cervical mucus, preventing the transport of sperm. (Ovulation still occurs)
What are some advantages of the POP?
-can be used when COCP cannot.
What are some disadvantages of the POP?
-Can cause irregular bleeding
-Must be taken at the same time every day (within 3 hours or else not effective)
What form of contraception inhibits the implantation of the zygote?
what are the 2 types of contraceptive coil?
-Intrauterine system (IUS)
-Intrauterine device (IUD)
How does the intrauterine system work?
it contains progestegon which decreases endometrial receptivity, meaning a conceptus cannot implant into the uterus.
Endometrial proliferation is reduced.
Also thickens cervical mucus as a secondary action.
Ovulation is not inhibited.