The recommended emergency contraception (EC) options available in the United Kingdom for women who have had unprotected intercourse include the copper intrauterine device (Cu-IUD) and oral emergency contraception (EC) pills NICE CKS.
- Copper Intrauterine Device (Cu-IUD): The Cu-IUD is considered the most effective method of EC and should be offered to all women, provided the criteria for insertion are met and the method is acceptable NICE CKS. It can be inserted up to 120 hours (5 days) after unprotected sexual intercourse (UPSI) NICE CKS. It can also be considered if it is currently within 5 days after the earliest likely date of ovulation, even if more than 120 hours have passed since UPSI NICE CKS. The Cu-IUD is the preferred option if a woman is taking liver enzyme-inducing drugs NICE CKS.
- Oral Emergency Contraception (EC): If the Cu-IUD is contraindicated or not acceptable, oral EC should be considered NICE CKS. The choice of oral EC depends on several factors, including the time since UPSI, current medications, and the woman's body mass index (BMI) or weight NICE CKS.
- Ulipristal Acetate: This oral EC can be used up to 120 hours (5 days) after UPSI NICE CKS. It is generally offered if the last UPSI occurred between 96 and 120 hours ago NICE CKS. It is also preferred if UPSI is likely to have taken place during the 5 days before the earliest likely date of ovulation, or if the woman is unsure NICE CKS. For women with a BMI over 26 kg/m² or body weight over 70 kg, ulipristal acetate is an option when UPSI is unlikely to have occurred during the 5 days before ovulation NICE CKS. Regular contraception should be started 5 days after taking ulipristal acetate NICE CKS. Ulipristal acetate is not recommended if taking liver enzyme-inducing drugs NICE CKS.
- Levonorgestrel: This oral EC is effective if taken as soon as possible and within 72 hours of UPSI NICE CKS. If ulipristal acetate is not suitable (e.g., if UPSI is likely to have taken place during the 5 days before ovulation), levonorgestrel can be offered NICE CKS. For women with a BMI less than 26 kg/m² or body weight less than 70 kg, levonorgestrel is an option when UPSI is unlikely to have occurred during the 5 days before ovulation NICE CKS. A double dose (3 mg) of levonorgestrel, taken as a single dose, is recommended as an off-label option if the woman is taking liver enzyme-inducing drugs NICE CKS. Immediate quick start of suitable hormonal contraception can be initiated with levonorgestrel NICE CKS.
It is important to note that oral EC is unlikely to be effective if ovulation has already occurred NICE CKS. All methods of EC, including the Cu-IUD, should be offered to adolescents NICE CKS. Health professionals should also ensure young women are advised that oral EC needs to be used as soon as possible and that other methods are more effective and reliable for primary contraception NICE.