Emergency contraception

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Emergency contraception is a specific birth control pill that may prevent pregnancy after unprotected intercourse. Emergency contraception is intended for occasional use as the word "emergency" implies. Emergency Contraception Pills are often referred as ECP's or EC's. The pill is commonly named Morning-after pill‎ because it is actually taken after intercourse.

Questions we could ask ourselves

How Does Emergency Contraception Work?

The role of emergency contraceptive pills (also called "morning after pills" or "day after pills") is to delay ovulation (the time in a woman's cycle when one of her ovaries releases an egg)

If emergency contraceptive pills are taken before fertilization (the point when the egg and sperm meet), they may interfere with the process of fertilizing the egg, for instance making it harder for the egg or the sperm to travel (and meet up) in the reproductive tract.

It’s also possible that emergency contraceptive pills work after fertilization, making it impossible for the fertilized egg to get implanted in the uterus.
Take a look at Figure 1 to see the difference of probability of not getting pregnant with and without emergency contraception by days of ovulation.

Concerning the Intra Uterine Device (IUD), most of them do not affect ovulation but like emergency contraceptive pills, it can prevent sperm from fertilizing an egg. It may also prevent implantation of a fertilized egg.

Emergency contraceptive pills are not the same as the abortion pill. There is no time when emergency contraception would end a pregnancy once it has started. Emergency contraceptive pills don’t have any effect if the person is already pregnant. If she decides to have use an IUD for emergency contraception, her health care provider would test her first to confirm she is not already pregnant.

What is the role of Progestin?

Progestin is a synthetic form of progestogen. This hormon will inhibit ovulation in ~50% of cycles and rely mainly on their progestogenic effect of thickening the cervical mucus and thereby reducing sperm viability and penetration.
Thus Progestin may be used in ordinary birth control pills.
Taken in form of emergency contraception pill it will prevent the implantation of the fertilized egg in the uterus.

What is the role of Estrogen?

Estrogens are a group of steroid compounds functioning as the primary female sex hormone. While estrogens are present in both men and women, they are usually present at significantly higher levels in women of reproductive age.
They are responsible of the development of female secondary sex characteristics, such as breasts, and are also involved in the thickening of the endometrium and other aspects of regulating the menstrual cycle.
Within the context of emergency contraception, estrogens are used combined to progestogen in high doses in Yuzpe regimen.
One important fact to notice would be that Estrogen is known to be extremely carcinogenic, especially for endometrial and breast cancers! This is why the Progestin-Only method is now largely favored as Contraception regimen.

Are there different Emergency Pills?

Yes there are different types of Emergency Pills classified after the type and level of hormones they contain.

The progestin-only method

The progestin-only method also called Plan B. The package for Plan B has two emergency contraceptive pills (each containing 0.75mg of levonorgestrel, which is the synthetic progestogen used as an active ingredient in hormonal contraceptives), and the instructions tell to take the first one 72h (3 days) after unprotected intercourse, the second one 12h afterwards the first pill.
But there are also doses where the 1.5 mg are taken at once.

Progestin-Only Method goes under different names.

  • Plan B
  • Levonelle
  • NorLevo
  • Postinor-2

The combined or Yuzpe regimen

The Yuzpe Regimen uses a combination of estrogen and progestogen, it is taken in two doses:
First two pills taken within 72 hours of unprotected intercourse, and a second dose of two pills 12 hours later.
Until recently, the Yuzpe regimen was the only hormonal method available for emergency contraception. [1]

What are the side effects of emergency contraceptive pills?

Side effects are more common with combined (Yuzpe) ECP regimens than with progestin-only ECP regimens. These side effects generally do not last more than 24 hours, and may be reduced for some women by providing anti-nausea medication before the emergency treatment.

Progestin-only regimen

  • Nausea (23%) and/or vomiting (6%)
  • Breast tenderness (8%)
  • Diarrhea (4%)
  • Irregular Bleeding (31%) and/or Heavy Menses (3%)
  • Headache or Dizziness (11%)
  • Fatigue (17%)

Yuzpe regimen

  • Nausea (51%) and/or vomiting (19%)
  • Breast tenderness (? %)
  • Irregular Bleeding and/or Heavy Menses (? %)
  • Headache or Dizziness (17%)
  • Fatigue (29%)

Percentage references:

  • [2] Task Force on Postovulatory Methods of Fertility Regulation. Randomised controlled trial of levonorgestrel versus the Yuzpe regimen of combined oral contraceptives for emergency contraception. Lancet. 1998;352:428-433.
  • [3] von Hertzen H, Piaggio G, Ding J, Chen J, Song S, Bartfai G, Ng E, Gemzell-Danielsson K, Oyunbileg A, Wu S, Cheng W, Ludicke F, Pretnar-Darovec A, Kirkman R, Mittal S, Khomassuridze A, Apter D, Peregoudov A; WHO Research Group on Postovulatory Methods of Fertility Regulation. Low dose mifepristone and two regimens of levonorgestrel for emergency contraception: a WHO multicentre randomised trial. Lancet. 2002;360:1803-1810.

What is the difference between emergency contraception, the "Morning after pill", and the "Day after pill"?

Actually, there is no difference.
Emergency contraceptive pills are often called "morning after pills" and sometimes even "day after pills" because you can use them after sex to prevent pregnancy. Most of the time, when someone mentions “emergency contraceptive pills,” “morning after pills,” or the “day after pill,” they are talking about using the same hormones found in regular daily oral contraceptive pills to reduce your chances of becoming pregnant if you had sex without using contraception, you think your birth control failed, or you were forced to have sex.
Even though there’s no difference between these terms, calling emergency contraceptive pills “morning after pills” or “day after pills” can be misleading because you can use them right away – and you have up to 120 hours (five days) after sex to take the pills and still prevent pregnancy. That means you don’t have to wait until the morning after, and you can still use emergency contraception even if it takes you longer than the morning after to get it.
In addition to this, it is better to start using emergency contraception as soon as possible because it is most effective the sooner it is taken after sex.

How effective is Emergency Contraception?

Emergency Contraception is most effective when taken within the first days that follow the intercourse. The effectiveness and how much it reduces the risk of getting pregnant will depend on the kind of emergency contraception that is used and how quicky it is taken after unprotected sex. In general the progestin only method is more effective than the combined ones.
Take a look at Figure 2 to see the Proportion of Pregnancies Prevented by the use Levonorgestrel vs. the use of the Yuzpe Regimen.
Take a look at Figure 3 to see the Proportion of Pregnancies Prevented by using Levonorgestrel vs. using Yuzpe by Timing of Treatment.

How and When is Emergency Contraception used?

Can the emergency Pill be taken the day before?

Emergency contraceptive pills should be taken after sex. It is not known if they will protect against pregnancy from sex that occurs after the pills are taken.

Is there a limit in which the emergency contraception can be used?

No, there is no actual limit in which this pill can be used, it will still be as effective to prevent pregnancy as the first time it has been used. But it is not a very good method; it is not as reliable as the pill or condoms, it produces also a lot of unpleasant side effects. On top of all it is of questionable ethical practice.

Is a prescription needed to get emergency contraceptive pills?

  • In the United States, the emergency contraceptive pill "Plan B" is approved for sale without prescription to women and men 18 and older.

Women 17 and younger still need to get a prescription from a licensed health care provider in order to get emergency contraceptive pills. While some providers may have emergency contraception on hand and can give you the pills directly, you will often also need to visit a pharmacy to fill the prescription just like you do with other medications.
Laws in some states also allow pharmacists to provide emergency contraceptive pills directly to women 17 and under without requiring a doctor's prescription (although not every pharmacist is doing it).

  • In Switzerland, emergency contraceptive pills are sold without prescription to women older than 16.

In addition to this, pharmacists must have a discreet maintenance with their clients and follow a protocole of advice axed on information (STD, AIDS...). For women under 16, a consultation in a hospital, a familial planning centre or at the doctor's must be followed before receiving the emergency contraception pill.

Are contraceptive pills safe?

Does the morning after pill prevent Sexually Transmitted Diseases ?

No the pill does absolutely NOT prevent infections such as STDs!
It does not avoid contact of body parts or fluids that carry the pathogen and thus can lead to infections, Condoms are here the best protection!

Could emergency contraceptives induce an Ectopic pregnancy?

It was long feared that emergency contraception pills might induce an ectopic pregnancy ,also called extra-uterine pregnancy, which is actually a complication of pregnancy. More precisely its when the fertilized ovum, instead of implanting in the uterus, as it should do, implants in an other tissue such as the Fallopian tube (so-called tubal pregnancies), cervix, ovaries, or the abdomen because it is unable to reach the uterus.
An embryo implanted elsewhere than the uterus can cause great tissue damage in its efforts to reach a sufficient supply of blood. This will cause bleedings and thus expels the implantation out of the tubal end it's known as tubal abortion.
However it may be dangerous if the bleedings do not achieve to expel the implantation, the embryo still growing in the Fallopian tube will provoke it's rupture! A surgical intervention is then absolutely required!
But a recent study revealed that out of over 33,000 women who used Emergency Contraceptives, only 5 ectopic pregnancies were reported. Which is actually the same than the expected rate of ectopic pregnancy in the general population! (Cheng et al., 2004; Farquhar, 2005) [4]

Can emergency contraceptive pills cause birth defects?

No. Emergency contraceptives do not seem to cause birth defects. Besides of statistics two main reasons support this point. First of all, Emergency Contraceptives contain the same hormones as ordinary birth control pills. Studies have shown that women who continued to take the Pill without realizing that they were actually pregnant did not cause harm to the developpement of the foetus.
Second of all, the emergency contraceptives would be taken long before the organs of the baby would start their process of organogenesis (developping organs). It is thus impossible for emergency contraceptives to lead to possible birth defects.

Does emergency contraception cause an abortion ?

No, using emergency contraceptive pills prevents pregnancy after sex. It does not cause an abortion. (In fact, because emergency contraception helps women avoid getting pregnant when they are not ready or able to have children, it can reduce the need for abortion.)
Emergency contraceptive pills or the IUD as emergency contraception work before pregnancy begins. According to leading medical authorities – such as the National Institutes of Health and the American College of Obstetricians and Gynecologists – pregnancy begins when the fertilized egg implants in the lining of a woman's uterus. Implantation begins five to seven days after sperm fertilizes the egg, and the process is completed several days later. Emergency contraception will not work if a woman is already pregnant, and it also will not harm the woman or her fetus.
However there are some ethnic groups that consider that pregnacy starts with fertilisation and thus consider the emergency contraception as a abortion method... For further reading go to the Contraception Ethics article.

How are emergency contraceptive pills different from the abortion pill ?

The abortion pill (also known as mifepristone or RU-486), is a completely different drug from Plan B and the other brands of birth control pills that you can use for emergency contraception. Emergency contraceptive pills contain common female hormones, either progestin alone or progestin combined with estrogen. These hormones prevent pregnancy, they do not cause an abortion.
Mifepristone, which is sold in the United States under the brand name Mifeprex, belongs to a new class of drugs known as antiprogestins, which stop the development of a pregnancy once it has started (which happens once a fertilized egg implants in the uterus). This drug is approved for use in early abortions in the United States, and many other countries. At a far lower dose, mifepristone has been shown to also be effective for preventing pregnancy, like emergency contraceptive pills, but it is only available for this use in China.

Sources we used

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