Emergency contraceptive pills
Be aware that this contraceptive method is not for regular use, but intended only for emergency situations.
Emergency contraceptive pills (ECPs) are hormonal methods of contraception that can be used to prevent pregnancy following unprotected sexual intercourse. Some women call this method 'morning-after pills'or 'post-coital pills'.
ECPs contain the same concentrated dose of hormones found in daily contraceptive pills. You will remember from your study session on oral contraceptives that these comprise combined pills containing oestrogen and progesterone, and pills containing progesterone only.
The exact mechanism by which emergency contraceptive pills prevent pregnancy is not completely understood. But the principles behind the mechanism of action are summarised in Box 10.2.
Box 10.2 Mechanism of action of emergency contraceptive pills
Emergency contraceptive pills work in a number of different ways:
- If the ovaries have not yet released an egg (ovulation), they can stop or slow down this process (called the suppression of ovulation).
- If an egg has already been released, they can stop sperm from fertilising it by thickening the cervical mucus to make it difficult for sperm penetration.
- If an egg has already been released and been fertilised, they can prevent it from implanting in the uterus wall by thinning the endometrial lining of the uterus.
If a woman is already pregnant when she uses ECPs, they will not cause an abortion, or any disruption to the fertilised egg, once implantation has taken place. So they do not affect an existing pregnancy.
Women who take ECPs should understand that they could still become pregnant the next time they have sex, unless they immediately start using another method of contraception. This is because ECPs delay ovulation in some women, so they may be at their most fertile soon after taking ECPs. You should therefore advise women that they use condoms until the beginning of their next menstrual period. For ongoing protection from pregnancy, they must start using another contraceptive method at once.
Combined emergency contraceptive pills
Combined emergency contraceptive pills are formulations of oestrogen (commonly ethinyl estradiol) and progesterone (commonly levonorgestrel or norgestrel). There are two common types of combined emergency contraceptives available in Ethiopia, and it is recommended that they be taken within five days following unprotected sexual intercourse.
µg means 'microgram'.
- The Neogynone pill contains 50 µg ethinyl estradiol and 0.5 mg norgestrel. You give two pills as the first dose as soon as convenient within five days (120 hours) after unprotected sexual intercourse. The second dose of the two pills should be after 12 hours. This is a total of four pills within a 12-hour period.
- The Eugynon pill contains 30 µg ethinyl estradiol and 0.3 mg norgestrel. You give four pills as the first dose within five days (120 hours) after unprotected sexual intercourse, and another four pills after 12 hours as a second dose. This is a total of eight pills within a 12 hour interval.
Progestin-only pills
The progestin-only or levonorgestrel pill has less effect than the combined one, but has fewer side-effects. The timing of the pill is the same as above.
- The Postinor pill contains 0.75 mg levonorgestrel. You give one pill as a first dose within five days (120 hours) of unprotected sexual intercourse, and the second dose of one pill should be repeated 12 hours after the first dose.
- If the only pill available is Microlut or Norgeston, which only contain 0.03 mg Levonorgestrel, then give 20 pills for the first and the second dose, each dose 12 hours apart, so a total of 40 pills are needed.
Effectiveness and precautions
The effectiveness of emergency contraceptive pills is dependent on the time taken after incidental unprotected sexual intercourse. If the client takes emergency contraception within five days (120 hours) of unprotected sexual intercourse, it can be as effective as 75% to 89% (WHO, 2007).
This range indicates to you that the sooner you give the pills to your client the better chance they have of preventing pregnancy. The pills work most effectively if started immediately after unprotected sexual intercourse, and work even more effectively if unprotected sex happened during the infertile days of the woman's menstrual cycle.
Can a woman still get pregnant after taking emergency contraceptive pills?
Yes, this method may fail to prevent pregnancy in the following situations:
- If the fertilised egg has already implanted in the uterus, because hormonal ECPs do not cause abortion.
- If too much time has passed since unprotected sexual intercourse.
- Because of the failure of the pill itself, as no method is 100% effective under all circumstances.
If the client has used emergency contraceptive pills and has not menstruated for a week or more after the expected date of menstrual bleeding, she may be pregnant. You should refer her for a pregnancy test to confirm the pregnancy. If the client is pregnant, you can explain to her the available options, and ask her to decide on the most appropriate option for her situation. If the client chooses to continue with the pregnancy, you can reassure her that emergency contraceptive pills will not have harmed the fetus.