What is the recommended emergency contraceptive pill after unprotected sex?

Emergency Contraception Options After Unprotected Sex

Ulipristal acetate (30 mg single dose) is the recommended emergency contraceptive pill after unprotected sex, especially when taken 3-5 days after intercourse, as it maintains effectiveness throughout the full 120-hour window. 1

First-Line Emergency Contraception Options

• The copper intrauterine device (Cu-IUD) is the most effective emergency contraception option, which can be inserted within 5 days of unprotected intercourse 2, 1
• For oral emergency contraception, the following options are available (in order of effectiveness):
  • Ulipristal acetate (UPA): single 30 mg dose, effective up to 5 days (120 hours) 2, 3
  • Levonorgestrel (LNG): single 1.5 mg dose or split dose (0.75 mg followed by 0.75 mg 12 hours later), most effective within 72 hours 2, 4
  • Combined estrogen and progestin regimen: less effective and associated with more side effects like nausea and vomiting 2

Comparative Effectiveness

• Cu-IUD is highly effective as emergency contraception with the highest efficacy of all options 2, 1
• UPA maintains consistent effectiveness throughout the full 120-hour window with observed pregnancy rates as low as 1.3% when taken between 96-120 hours 3, 5
• UPA has been shown to be more effective than LNG when taken 3-5 days after unprotected intercourse 2, 6
• UPA has a pregnancy risk 42% lower than LNG up to 72 hours, and 65% lower in the first 24 hours following unprotected intercourse 5
• LNG effectiveness decreases significantly after 72 hours, with pregnancy rates increasing at 4-5 days 2, 7
• The combined estrogen and progestin regimen is less effective than both UPA and LNG 2

Special Considerations

• BMI impact: LNG may be less effective in women with higher BMI (>30 kg/m²), while UPA maintains better effectiveness in this population 2, 3
• Timing: All emergency contraception should be taken as soon as possible after unprotected intercourse for maximum effectiveness 2, 7
• After UPA use, any regular contraceptive method can be started immediately, but barrier contraception or abstinence is needed for 14 days or until next menses 2
• After LNG use, any regular contraceptive method can be started immediately with barrier contraception or abstinence needed for 7 days 2

Clinical Algorithm for Emergency Contraception

1. If within 5 days of unprotected intercourse and Cu-IUD is appropriate and available: Choose Cu-IUD (most effective option) 2, 1
2. If oral contraception is preferred or Cu-IUD is not an option:
   • Within 120 hours (5 days): Ulipristal acetate 30 mg single dose 3, 8
   • Within 72 hours only: Levonorgestrel 1.5 mg single dose 2, 4
3. For women with BMI >30 kg/m²: UPA is preferred over LNG due to maintained effectiveness 1, 3

Important Counseling Points

• Advise patients that emergency contraception is not 100% effective 7
• Recommend a pregnancy test if the woman does not have a withdrawal bleed within 3 weeks 2
• Consider advance provision of emergency contraception to increase likelihood of timely use 2, 1
• UPA can prevent pregnancy even when administered in the advanced follicular phase, when LNG is no longer effective in inhibiting ovulation 9