What do contraceptives do?
Why do women choose to use contraceptives?
Family planning - no. of children and timing; to avoid unplanned pregnancy
For non-contraceptive reasons
How many babies are born every two seconds?
Six babies every two seconds
The prevalence of contraceptive use is higher in (high / low) income countries.
high income countries
What are some non-contraceptive reasons for using contraception?
Heavy, irregular or painful periods
Premenstrual syndrome (abdo pain, bloating, cravings...)
Contraceptive use is described in terms of perfect use and typical use.
What's the difference between these two?
Perfect use - 100% compliance, never forgetting
Typical use - allows for occasional omission
Obviously effectiveness is less for typical use, but it's more realistic
How long can sperm live in the female reproductive tract for?
How long does an egg survive in the female reproductive tract once released from the ovaries?
12 - 24 hours
For the greatest chance of conceiving, when in the menstrual cycle should a woman have sex?
Days preceding and following ovulation
Ovulation occurs at roughly Day 14, so Days 8 - 18 ish
What measurement is used to describe the effectiveness of contraceptive methods?
What does the Pearl index describe?
No. of contraceptive failures per 100 women per year
How is the Pearl index calculated?
(Number of accidental pregnancies) x 1200 / Total number of months using contraceptive
How long do
survive in the female reproductive tract?
a) 5 days
b) 12 - 24 hours
The Pearl index describes the number of ___ pregnancies experienced per ___ women per year.
accidental pregnancies per 100 women per year
It's a measure of how effective a contraceptive method is
How does body temperature change around the time of ovulation?
Basal body temperature increases by around 1 degree Celsius
From 36 to 37 degrees Celsius, supports the sperm and eggs
How does the position of the cervix change around ovulation?
Cervix rises up into vagina and the internal + external os open up
What are the properties of cervical mucus around the time of ovulation?
Thin and slippery
So the sperm can swim through it easier
Sorry for the imagery
What are two natural methods of contraception?
Withdrawal method - man pulls out before he ejaculates
Lactational amenorrhoea - post-natal state that lasts for up to 6 months
What is the Pearl index for no contraception use in a sexually active woman?
i.e 85 out of 100 sexually active women would fall pregnant each year if they didn't use contraception
What is the Pearl index for the withdrawal method?
22 i.e 22 out of 100 women will fall pregnant each year if the man uses the withdrawal method
Because there's no barrier to sperm entry and it all relies on the man's reflexes, plus a large proportion of sperm are contained in the initial ejaculate so he has to be quick
What are the three criteria for lactational amenorrhoea to be an effective state of natural contraception?
1. Woman is exclusively breastfeeding
2. Less than 6 months post-birth
3. Woman isn't have periods
What is the most commonly used contraceptive method in the UK?
Combined hormonal contraception (CHC)
i.e the oestrogen/progrestrogen contraceptive pill
The CHC stops ___.
The CHC is (short / long)-acting.
has to be taken daily
What is the Pearl index of the CHC?
i.e 0.2 per 100 women getting pregnant per year, very effective
Apart from the CHC, which other hormonal tablet is used for contraception?
Progesterone only pill / Desogestel / "Mini pill"
The mini pill contains a progesterone precursor called ___.
Apart from tablets, what are other medical methods of contraception?
Barriers - male and female condoms, diaphragms and caps
Intrauterine system (IUS)
Intrauterine device (IUD)
Male and female sterilisation
What are three adaptations the female reproductive tract makes around the time of ovulation to increase the likelihood of pregnancy?
Basal body temperature increases
Cervical mucus becomes thin and "slippery"
Cervix rises and internal + external os open
For how long does the average contraceptive implant last?