PocketGuide: Emergency Contraception

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PocketGuide for Family Planning Service Providers

Emergency Contraception

When sexual intercourse occurs without contraceptive protection, unplanned and undesired pregnancy can result. Fortunately, because there are highly effective methods to prevent such pregnancies, clients need not be turned away to anxiously await their menstrual period. Unfortunately, few clients are aware of the availability and safety of such methods. To correct this, health care providers should routinely educate clients about emergency contraception. In addition, family planning programs may want to consider providing emergency contraceptives as a preventive measure.

While most contraceptives are appropriate before intercourse, several methods also can be used within a short time after unprotected intercourse. Often called “morning after pills,” they are better named secondary or emergency contraceptives. These names remove the idea that the user must wait until the morning after unprotected intercourse to start treatment or that she will be too late if she cannot obtain the pills or an IUD until the afternoon or night after intercourse.

Currently there are two types of emergency contraceptives: mechanical and chemical. The only mechanical method is the IUD. When inserted up to 5 days after unprotected intercourse, copper-releasing IUDs can prevent a pregnancy from becoming established. In terms of chemical methods, fifteen regimens using oral contraceptives are said to exist, but only four have been adequately studied and are recommended for widespread use. In some countries increased demand for emergency contracetpion has led to special packaging of oral contraceptives (COCs and POPs) for this use.

Risk of Already Being Pregnant

Before providing emergency contraception be sure the client is not already pregnant (i.e., she might have become pregnant in the previous month). Symptoms of early pregnancy may include:

Breast tenderness
Nausea
Change in the last menses (light flow, short duration, etc.)

If pregnancy is suspected, before providing emergency contraception counsel the client regarding her options and the small risk of potential problems if she is already pregnant.

Breastfeeding Women

If a woman is fully breastfeeding, amenorrheic and fewer than 6 months postpartum (using LAM), she should not need emergency contraception. If she is breastfeeding but not using LAM and thinks she might be pregnant, emergency contraception may be used. The effect on lactation and risk to the infant are minimal.

Risk to Clients with Vascular Problems

Women who are at increased risk of vascular problems (current or past blood clotting problems, heart attack or stroke) should be advised of a slight additional risk of a serious complication if they use the high-dose (50痢) estrogen regimens (COCs or estrogen-only pills). COCs taken for a short duration (2 days) in a physically active client, however, are highly unlikely to cause a serious problem even in women with these risks; therefore, do not withhold treatment if client requests it.

Risk of Becoming Pregnant

The risk of becoming pregnant depends on the day of the woman's cycle in relation to ovulation. Calculating the exact risk is best done using data in which only a single act of intercourse potentially could have led to conception. On the basis of 129 such cycles, Wilcox et al (1995) observed that the risk of pregnancy increased from 8% at 5 days before ovulation to 36% on the day of ovulation (see white bars in Figure 1). These new data indicate that the fertile period lasts only about 6 days, is clustered around a 2 to 3 day interval (days -2 to 0) and ends on the day of ovulation (i.e., cycle days 9 to 14 of a 28 day cycle). The decrease in fertility immediately following ovulation (day 0) suggests a short survival time for ova (less than 24 hours) as well as a rapid change in the cervical mucus that may prevent entry of new sperm.

Figure 1. Probability of Conception by Cycle Day

Figure 8. Probability of Conception by Cycle Day

Adapted from: Wilcox et al 1995.

Use of emergency contraception during the fertile period reduces the risk of pregnancy by at least 75%. For example, as shown in Figure 1 (gray bars) a 36% risk would be reduced to about 9%. Overall, however, only 1–3% of women emergency contraception become pregnant during that cycle. In practice, because the fertile period for a given cycle can only be estimated, it is often difficult to assess accurately a woman's risk of becoming pregnant. Fortunately, because all emergency contraceptives are quite safe, their use is appropriate any time in the cycle when a woman is concerned she might be pregnant.

Management of Nausea and Vomiting

Because of the high total dose of estrogen in COCs, nausea is a common side effect. If accompanied by vomiting within the first 2 hours, the effectiveness of COCs when used for emergency contraception may be decreased.

To minimize nausea and vomiting, advise clients to take each dose with food. If appropriate, taking the first dose at bedtime may reduce nausea and vomiting.
While there is some decrease in nausea and vomiting if anti-emetics are taken prophylactically, routine use is not recommended. They are of no help if given after vomiting has started.
If vomiting occurs within 2 hours of taking the first or second dose:

the client may repeat the dose, or
consider administering the dose vaginally.

An extra treatment (e.g., 8 COC tablets containing 30-35 痢 EE each) may be given to clients for use as backup.

Client Information for COCs

There is no reported harm to the woman or developing embryo from the small amount of estrogen and progestin in COCs taken for 2 days. It is, however, unwise for a woman to take any drugs in early pregnancy unless absolutely necessary.
If a client is pregnant at the time she takes COCs, their use will not cause an abortion.
COCs taken for a short duration (2 days) are highly unlikely to cause a serious problem even in women at risk for vascular problems (current or past blood clotting problems, heart attack or stroke).
About 8% of women using COCs for emergency contraception will have spotting during the treatment cycle. About 50% will get their menses at the expected time and most others will start menses earlier than expected.
Emergency contraception should not be used on a regular basis (from month to month) because it is much less effective than other methods.
Tell client how and when to start her chosen contraceptive method.

When to Return

A client should return to the clinic if she has:

no menses within 3 weeks (check for normal or ectopic pregnancy)
any concerns

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