Kontrasepsi Darurat

01Mechanism of Action

Emergency contraceptive pills work primarily by preventing or delaying ovulation. This is the central teaching concept and the most tested point: ECPs do not terminate an established pregnancy, they do not disrupt implantation, and they are not abortifacients. Both the Kemenkes and BKKBN guidelines explicitly state this.

Levonorgestrel (LNG) is a synthetic progestogen. At the high doses used in emergency contraception, it suppresses the LH surge, thereby blocking follicular rupture. If ovulation has already occurred, LNG has no meaningful effect on fertilization or implantation, which is why timing matters greatly: the earlier LNG is taken after unprotected intercourse, the higher its efficacy.

Ulipristal Acetate (UPA) is a selective progesterone receptor modulator. Unlike LNG, UPA can delay ovulation even after the LH surge has already begun, which gives it a wider effective window. This is why UPA maintains higher efficacy at 72 to 120 hours compared to LNG, and why it is preferred in women with BMI above 25 kg/m², a population in which LNG performs no better than placebo according to the Kemenkes guideline footnotes.

Copper IUD works through a different pathway entirely. The copper ions released from the device create a sterile inflammatory reaction within the uterus that is toxic to sperm. This impairs sperm motility and viability, preventing fertilization. Because its mechanism is not ovulation-dependent, it is the most effective form of emergency contraception and retains full efficacy across the entire 5-day window. It also transitions directly into a long-acting reversible contraceptive method.

02Types and Dosing Regimens

Copper IUD as Emergency Contraception

The Copper IUD (Cu-T 380A) can be inserted within 5 days of unprotected intercourse. The guidelines add an important nuance: if the timing of ovulation can be estimated, the IUD may be inserted more than 5 days after intercourse, as long as insertion occurs within 5 days after ovulation. This distinction may appear in vignettes involving women who track their cycles.

Emergency Contraceptive Pill Regimens

The exam loves the detail that when dedicated emergency contraceptive pills are unavailable, regular oral contraceptive pills can be substituted using the Yuzpe method. The required pill count changes depending on the formulation. Test-writers may present a scenario where a woman presents to a rural clinic without dedicated ECP stock and ask what to give and how many tablets.

03Medical Eligibility Criteria

Pill ECP Eligibility (WHO Categories)

Category key: 1 = can be used without restriction; 2 = generally usable (benefits outweigh risks); 3 = not recommended; 4 = contraindicated.

A critical teaching point: pregnancy is listed as "NA" (Not Applicable), not as a contraindication. This reflects the fact that ECPs will not harm an existing pregnancy. They simply have no role to play once pregnancy is established.

Note the Kemenkes guideline specifically flags that pill ECP may be less effective in women with BMI 30 kg/m² or above compared to those with BMI below 25, but this is an efficacy concern, not a safety concern. The category remains 1. For overweight or obese patients, consider UPA (superior efficacy over LNG in this group) or Copper IUD (efficacy unaffected by BMI).

Copper IUD Eligibility for EC Use

This is a high-yield distinction. In a sexual assault victim, the decision to use a Copper IUD depends on the STI risk profile. If the patient is at high risk for STIs (e.g., unknown assailant, multiple attackers, anal or genital trauma), the Copper IUD is category 3 and pills are preferred. If STI risk is low, the IUD is category 1.

04Indications and Contraceptive Failure Scenarios

The numbers to memorize: 3 missed pills, 1 week late for monthly injection, 4 weeks late for 3-monthly injection.

05Starting or Switching to Ongoing Contraception After EC

This is where the guidelines have dense, testable content. The rules differ depending on whether the patient took LNG/combined ECP versus UPA, because UPA interacts with progestogen-containing contraceptives.

After LNG or Combined ECP (Yuzpe)

The principle is simple: any hormonal method can be started immediately on the same day, but the patient needs 7 days of additional contraception (abstinence or condoms) because the new method takes time to suppress ovulation independently.

After Ulipristal Acetate (UPA)

The key concept here is the drug interaction between UPA and progestogens. UPA is a progesterone receptor modulator; if exogenous progestogen is introduced while UPA is still active, the two agents antagonize each other and both become less effective. That is why the guideline mandates a 6-day waiting period before initiating any progestogen-containing method after UPA.

The Copper IUD is the exception because it contains no hormones and therefore does not interact with UPA. It can be placed on the same day.

06Side Effects and Practical Pearls

Emergency contraceptive pill side effects are generally mild and self-limiting:

If vomiting occurs within 2 hours of taking the ECP dose, the dose must be repeated. However, routine prophylactic anti-emetics before ECP use are not recommended by either guideline.

LNG-only pills and UPA are preferred over the Yuzpe method precisely because they cause less nausea and vomiting.

Repeated or frequent use of ECPs is not inherently dangerous for women classified as category 1 for that method. However, repeated use can lead to menstrual irregularity and is a signal that the patient should be counseled toward a regular contraceptive method. For women with conditions classified as category 2, 3, or 4 for regular combined or progestin-only pills, frequent and repeated ECP use may carry additional risk.

07Differential Comparison

08Traps and High-Yield Pearls

The most common way students lose points on emergency contraception questions is by confusing the switching rules after UPA versus after LNG. If a vignette shows a woman who took UPA and then asks when she can start her implant or injectable, the answer is day 6, not the same day. The reasoning is the drug-drug interaction: UPA is a progesterone receptor modulator, and simultaneous progestogen exposure reduces the efficacy of both agents.

A second classic trap is the BMI question. A vignette may present an obese woman (BMI above 25 or 30) requesting emergency contraception. Students who choose LNG will miss that, per the Kemenkes algorithm footnotes, LNG performs no better than placebo at higher BMI values. The correct answer is either UPA (better efficacy at high BMI) or Copper IUD (efficacy completely independent of body weight).

Third, students often forget that the Copper IUD is the most effective emergency contraceptive and that it doubles as immediate long-acting contraception. In any vignette where the patient has no contraindications to IUD placement and is within the time window, the IUD is the best answer, especially in a woman who also needs ongoing contraception.

Fourth, the vomiting rule: if a patient vomits within 2 hours of oral ECP, the dose must be repeated. But prophylactic anti-emetics before ECP ingestion are not standard practice per these guidelines.

Finally, remember the eligibility distinction for Copper IUD use after sexual assault. High STI risk makes the IUD category 3 (not recommended); low STI risk keeps it at category 1 (unrestricted). This is the only scenario where the Copper IUD for EC is relatively contraindicated, and test-writers use it to check whether students are thinking about the clinical context beyond just the time window.