Contraception, Infertility Flashcards
What is contraception
Preventing the egg and sperm meeting or a fertilised egg implanting in the uterus
What are hormone based contraception
The mixed pill - what does it do
oral, Uses female hormones to prevent pregnancy. Pill gives Low doses of oestrogen and some progesterone inhibiting release of FSH by pituitary gland affecting ovaries so no eggs mature
Also stops uterus lining developing preventing implantation
Also makes cervix mucus thick to prevent sperm getting through
Disadvantages of the contraceptive pill
Raised blood pressure
Thrombosis
Breast cancer
Progesterone only pill - how it works?
Fewer side effects
Must be taken regularly
Otherwise artificial hormone level drop and body own hormones take over quickly causing unexpected release of an egg and baby!
Contraceptive implant
Can last up to 3 years Tiny tube inserted under skin by doctor Releases progesterone slowly 99.95% effective Progesterone injections are similar but last only 12 weeks
Contraceptive patch
Like the mixed pill
Contains oestrogen and progesterone
Stick to skin replace every 7 days
Hormones absorbed into bloodstream
What are the chemical methods of contraceptive control and how do they work
Called spermicides
Kill or disable sperm
Easily available but not as effective as hormone based
What are the barrier methods of contraception and how do they work
Condom
Prevent sperm reaching egg
Condom- latex sheath on penis during inter course to collect semen to prevent egg and sperm meeting
No side effects,
No medical advice
Also some protection against STDs eg HIV, syphillis
Can get damaged
how does Diaphragm or cap work?
Thin rubber diaphragm placed over cervix before sex to prevent entry of sperm
No side effects
Must be fitted by doctor initially
If not fitted correctly sperm may reach egg
Barrier methods work better combined with spermicides
What are intrauterine devices
Small structures inserted by doctor into uterus
Last 3-5 years but can be removed at any time to get pregnant
May contain copper and prevent early embryos implanting in lining of uterus
Others contain progesterone releasing slowly to prevent build up of uterus lining and thicken cervix lining.
Very effective but may cause infection or period problems
What is abstinence
Not having sex
Some religious groups do not allow artificial contraception
So abstaining around time of ovulation means sperm cannot fertilised egg
This is the rhythm method
No side effects but very unreliable despite using ovulation indicators
Surgical methods
Surgical procedures can prevent pregnancy
Men have sperm ducts cut and tied preventing sperm reaching semen - vasectomy
Women - oviducts cut or tied to stop egg reaching uterus and sperm reaching the egg - needs general anaesthetic
