Author: Manpreet Sahemey, Jessica Duckworth / Editor: Charlotte Davies / Reviewer: Jessica Duckworth, Manpreet Sahemey / Codes: / Published: 03/07/2018 / Reviewed: 12/08/2025
As an emergency medic you are unlikely to be in a position where you are asked to prescribe emergency contraception if you have a co-located urgent treatment centre or access to a sexual health clinic. However, you may be asked to do this out of hours, or as part of your assessment for sexual assault, or if you do event medicine, so its important to have an understanding of the available options and know where to refer patients when needed.
So, what are the available options for emergency contraception?
There are currently three licensed forms of emergency contraception: two hormone-based tablets (morning-after pills) and one non-hormonal coil (copper coil, or IUD). The decision of which to use depends on factors such as local availability, coil fitting services and how many hours post unprotected sexual intercourse (UPSI) the patient presents to you.
The Morning After Pills
Two types:
- Levonorgestrel (LNG) 1.5mg pill (Levonelle ) within 72hrs of UPSI
- Ulipristal Acetate (UPA) 30mg pill (EllaOne ) within 120hrs of UPSI
When can I give them?
Essentially, you can give EC pills to a patient anytime in their cycle in an emergency medicine setting. However, it is important to understand that they are only actually effective if given prior to ovulation, which for most people with a regular 28-day cycle, is in the first half of the menstrual cycle (days 1-14).
The EC pills work by delaying ovulation. Hence, they are only effective if given prior to ovulation. It is important to work out whether the patient has ovulated, which is a simple calculation. Ovulation occurs 14 days prior to the start of their period. In a regular 28-day cycle, ovulation occurs around day 14. If a patient has a 32-day cycle, ovulation occurs around day 18 (32 minus 14). If a patient has an irregular cycle, it is more challenging to calculate, but can be estimated safely by taking their shortest cycle length, and subtracting 14 days from that. Therefore, EC pills will only work prior to ovulation, so in a regular 28-day cycle, are only likely to be effective on days 1-14. If given on days 15-28, they are unlikely to be effective. Although, in an emergency medicine setting, it is worth giving EC pills at any stage of the cycle if a copper coil is not an option, as it is better than no emergency contraception at all.
Levonorgestrel (LNG-EC) or the Morning after pill – Levonelle
The morning after pill is probably the most familiar to patients and clinicians alike. It has been around for many years and is effective if taken at the right time in the cycle. Levonorgestrel 1.5mg (progesterone), commonly marketed as Levonelle , can be used up to 72hrs post-UPSI. It is most effective if taken within 12hrs, and its efficacy reduces with time: if taken at 24hrs, it will prevent 95% of pregnancies, and if taken at 72hrs it will prevent 58% of pregnancies.
Should a patient have another episode of UPSI, then Levonorgestrel can be taken again in the same cycle.
Common side effects include headache, nausea and irregular bleeding. If a patient vomits within two hours of taking, then they are advised to take another dose. Patients should be advised to take a pregnancy test 3 weeks post-UPSI.
Updated FSRH guidelines have advised that if a woman weighs more than 70kg or has a BMI >26, then double dosing of levonorgestrel should be given (3mg).
Contraindications to Levonorgestrel include acute porphyria, pregnancy, severe arterial disease, undiagnosed vaginal bleeding and a history of breast cancer within the last five years.
Ulipristal acetate (UPA-EC) or the Morning after pill – EllaOne
Ulipristal Acetate (UPA) has been licensed for use since 2010, and its brand name is EllaOne . It is up to 95% effective in preventing pregnancy for up to 120hrs post-UPSI (thats 5 days). It is thought to be more effective than the LNG-EC pill, as it works closer to the time of ovulation. Its mechanism is similar to Levonorgestrel, and it has a similar side effect profile. It can be given more than once if already taken in the same cycle. However, its effectiveness is reduced if the patient has been taking a progestogen (any hormonal contraception, including LNG-EC), either seven days prior or five days after UPA. Therefore, it absolutely cannot be used for pill failures/missed pills, or other types of expired contraception including implants/IUS/Depo injections. Contraindications to UPA include uncontrolled severe asthma, Gynaecological cancers and severe liver disease.
Copper Coil – Intra-Uterine Device (IUD)
The copper IUD provides reversible long-term contraception and is licensed for use as a form of emergency contraception up to 120hrs post-UPSI (5 days). It causes a foreign body reaction in the endometrium which prevents implantation and studies have shown that copper inhibits sperm motility. It is the most effective form of emergency contraception with a failure rate of only 0.6-0.8%. Most sexual health clinics and some GP surgeries can insert emergency IUDs. A copper IUD can be inserted at any point in the cycle, as long as it is within 120hrs (5 days) of UPSI, OR within 120hrs (5 days) of expected ovulation. If intended to be used as an ongoing form of contraception, it can be left in-situ for up to ten years depending on the type of coil used.
Complications include bleeding, infection (<1/100), expulsion (1/20) and perforation (1/1000). Contraindications to IUD insertion include pregnancy, within 48hrs to 4 weeks postpartum, undiagnosed vaginal bleeding, active infection or pelvic inflammatory disease and uterine fibroids or anomalies distorting the uterine cavity.
Summary Table of Emergency Contraception Pills
| Levonorgestrel (LNG) | Ulipristal Acetate (UPA) | |
| Brand Name | Levonelle | EllaOne |
| When can be given? | Within 72hrs post-UPSI | Within 120hrs post-UPSI |
| Dose | 1.5mg (3mg if >70kg/BMI>26) | 30mg |
| When in cycle | Prior to ovulation | Prior to ovulation |
| Effectiveness | 96 – 99% | 98 – 99% (slightly more effective) |
| Take >1x in cycle? | Yes | Yes |
| Important notes | Less effective if any progestogen has been taken 7 days prior or 5 days after, i.e. any hormonal contraception. | |
| Breastfeeding | Yes | Yes |
| Enzyme-inducers | Yes (double-dose to 3mg) | Reduced efficacy |
Signposting
Emergency hormonal contraception can be obtained from sexual health clinics, GP surgeries, NHS walk-in centres, urgent care centres and some local and online pharmacies. Emergency coils can be fitted by sexual health clinics and some GP surgeries.
Remember that emergency contraception does not protect against sexually transmitted infections (STIs) please advise the patient to attend a sexual health clinic for STI screening and follow-up care. Please also remember to check for any safeguarding needs. In cases of sexual assault, contact your local sexual assault referral centre for specialist advice.
Further Reading
- Faculty of Sexual & Reproductive Healthcare. FSRH Guideline Emergency contraception. London: FSRH; 2017 Mar [(amended 2023 Jul).
FSRH Flowcharts:
These flowcharts are fairly in-depth and aimed at Sexual Health professionals, but they are useful either way if you want to make a really informed choice about which type of Emergency Contraception to prescribe/recommend!
Flowchart on choosing type of Emergency Contraception
FSRH Flowchart on Choosing which type of EC Pill to give
