Emergency contraception: an update

There are now three choices of emergency contraception available but which one should you advise a woman to use? This update discusses each method in detail and summarises keys issues to consider during counselling.

The provision of emergency contraceptive services has an important role to play in reducing teenage pregnancies, in line with the Government's target to reduce the under-18 conception rate by 50%. But it is not only teenage girls who run the risk of becoming pregnant after unprotected sexual intercourse.

During the fertile period, the chances of conception are estimated to be between 10% and 33%, but there is a 3% risk of pregnancy from one unprotected act of sexual intercourse at any time during the menstrual cycle.

There are now three choices of emergency contraception available, the intrauterine contraceptive device, levonorgestrel 1.5mg tablets (Levonelle(R) 1500) and ulipristral 30mg tablets (ellaOne(R)).

INTRAUTERINE CONTRACEPTIVE DEVICE (IUD)

A copper intrauterine device (IUD) can be fitted up to 5 days after unprotected sexual intercourse or up to 5 days after the earliest calculated ovulation day in the cycle. It is almost 100% effective in preventing pregnancy and can offer prevention of pregnancy after multiple episodes of unprotected sexual intercourse if all are within the last 5 days or up to 5 days after earliest calculated ovulation.

This could mean that if a woman never has a cycle shorter than 28 days, that an IUD could be fitted up to day 19 of her cycle, this would cover all episodes of unprotected sexual intercourse up to day 19.

An IUD cannot be fitted for emergency contraception if there is a vaginal or pelvic infection, undiagnosed genital tract bleeding or if a woman is pregnant. As a woman who accesses this method for emergency contraception has had unprotected sexual intercourse these are potentially high risks, and will need to be excluded. Clients should be assessed for infection prior to insertion and may be given prophylactic antibiotics for chlamydia. Although further screening for sexually transmitted infections (STIs) should be carried out in 2 weeks to exclude infection from this episode of unprotected sexual intercourse, if the woman has HIV/AIDS then the risks of inserting an IUD outweigh the benefits, so she should be considered for emergency hormonal contraception.¹ As she may be taking antiretroviral medication, which, depending on the medication prescribed, can affect liver enzymes, the dose of emergency hormonal contraception may need to be increased.

If you are working in an area where there are no clinicians who are trained to fit an IUD and you have to refer the client to another service, it is good practice to give emergency hormonal contraception to the woman on presentation, in case an IUD cannot be fitted for any reason.² Women should be counselled about the risks of the IUD which include heavier periods, expulsion, perforation, infection and intra- or extra-uterine pregnancy.

An emergency IUD can be removed with the next period, or could be left in situ to be used for future contraception. If an IUD is to be removed, it is good practice to commence another form of contraception before removal. Prior to removal you should check that there has been no sexual intercourse in the previous 7 days, as sperm can live in the human body for up to 7 days, and sexual intercourse within this timeframe could result in pregnancy.

EMERGENCY HORMONAL METHODS

There are two hormonal methods available for emergency contraception, which is the term preferred to 'post-coital contraception' or the 'morning after pill' as it was commonly known and may still be so described by women.

LEVONELLE(R) 1500

Levonelle(R) 1500 is a single dose of 1.5 mg of the progestogen, levonorgestrel. It should be taken within 72 hours of the first act of unprotected sexual intercourse, but is most effective in the first 24 hours when it is 95% effective in preventing pregnancy. Efficacy is reduced to 84% if intercourse has occurred up to 72 hours before administration.³

There is less nausea and vomiting associated with this method compared with previous emergency contraception. Women can buy Levonelle without a prescription from a pharmacy at a cost of £24.00.

Women should be warned that if they vomit within 2 hours of taking Levonelle, the dose will need to be repeated. They should also be warned that their next period may be early or it may be delayed. If it is more than a week late, or not a normal period then she should attend for a pregnancy test. Levonelle does not provide any future contraception, so this will need to be discussed. Condoms may be used until the next period where an IUD, IUS, implant or injectable method may be commenced if there is no sexual intercourse from day 1 of the cycle. Alternatively, if there are no contra-indications to the method, you could fast track the woman on to the combined oral contraceptive pill or progestogen-only pill commencing the day after Levonelle with extra precautions for 7 days for the combined pill, 9 days for Qlaira, and 2 days for progestogen-only pills.⁴ This will delay the next menstrual period so a pregnancy test will need to be done in 3 weeks. If a woman reluctant to do this she could commence the progestogen pill or combined pill with her next period.

Drug interactions

Liver enzyme inducing drugs (see Box 3) reduce the efficacy of progestogen, and may continue to exert an effect for 4 weeks after cessation. There is no current advice for ellaOne, but advice for Levonelle 1.5mg is to increase the dose by 100%, so a stat dose orally of levonelle 3mg; two 1.5mg tablets should be given within 72 hours. This protocol is unlicensed but endorsed by the Faculty of Sexual and Reproductive Healthcare.^3,5

ELLAONE(R)

ellaOne is a more recent emergency contraceptive, which consists of 1 x 30mg tablet containing ulipristal acetate, a synthetic progesterone. Its mode of action is inhibition or delay of ovulation, but it also alters the endometrium receptivity. The synthetic progesterone receptor binds to human progesterone receptor and also has high affinity for the glucocorticoid receptor and antiglucocortoid effects have been observed in animals.

It is the only emergency hormonal contraceptive licensed for 120 hours. If a woman vomits within 3 hours of intake, the dose will need to be repeated.

ellaOne, given between 0 and 72 hours after unprotected sexual intercourse, has similar efficacy to Levonelle. Observed pregnancy rate was 1.5% in two clinical trials preventing 85 and 73% of expected pregnancies up to 72 hours.⁶ Glasier's randomised study of efficacy in 2,221 women compared ellaOne and Levonelle. Women were randomised to ellaOne (844) or Levonelle (852), given within 72 hours of sexual intercourse. There were 15 pregnancies (1.8%) with ellaOne and 22 pregnancies with Levonelle (2.6%). A further 203 women were given emergency contraception between 72 and 120 hours following sexual intercourse; 97 women were given ellaOne and 106 women were given Levonelle. Three pregnancies occurred, all in women given Levonelle. The most frequent side effect with both types of emergency contraception was headache.⁷

ellaOne reduces the efficacy of progestogen-containing products, and as a result may reduce efficacy of hormonal contraception: therefore, barrier contraception should be used until the next period, when hormonal contraception can be commenced.¹ Periods may be a 1 week early or 1 week late - 20% of women had a period more than 7 days late.

Ulipristal acetate is excreted in breast milk, so after intake of ellaOne breastfeeding is not recommended for at least 36 hours. Breast milk will need to be expressed and discarded. EllaOne is a 'Black triangle' medicine so any adverse drug reactions need to be reported.⁸

Drug interactions

Liver enzyme inducing drugs reduce the efficacy of ellaOne, but as there is no advice on what to do in this situation, it should be avoided in women taking these drugs. Enzyme induction may be affected up to 4 weeks after cessation. Proton pump inhibitors, antacids and H2 receptor antagonists may reduce plasma concentrations of ulipristral acetate and therefore decrease efficacy, so ellaOne should be avoided.

Emergency hormonal contraception is accessible and easily obtained and while not as effective in preventing pregnancy as routine contraception, it is low in risk. Levonelle is widely available, and at a cost of £5.20 is very cheap, whereas ellaOne costs £16.95. Both have comparable efficacy in preventing pregnancy in the first 72 hours after intercourse, but ellaOne is more effective in preventing pregnancy from 72 to 120 hours after unprotected intercourse, and if this was the only episode. If ellaOne has already been given in the cycle and a woman attends for further emergency hormonal contraception, it is not licensed to be given again in the same cycle. As ellaOne reduces the effect of hormonal contraception, if a client does not want an IUD or is this method is unsuitable, it may reduce the efficacy of a subsequent dose of Levonelle given. Women will therefore need to be counselled about this circumstance.

The Faculty of Sexual and Reproductive Health Care's Clinical Effectiveness Unit recommends that a woman uses extra precautions for 14 days if starting combined hormonal contraception (16 days extra precautions for Qlaira), or 9 days if starting the progestogen only pill immediately following ellaOne intake. This is outside the product licence, and women will need to be counselled to that effect. There is no evidence for possible interactions between ellaOne and hormonal contraception taken prior to ellaOne. However, if a woman does not want to get pregnant, commencing a hormonal contraceptive immediately following emergency contraception can reduce the potential for further unprotected sexual intercourse and, as a result, unintended pregnancy.⁴

Finally it is vital that health professionals keep up to date with the forever-changing information on contraception, and are suitably qualified to carry out and give appropriate advice on contraceptive and child protection assessment. The Faculty of Sexual and Reproductive Health Care (www.fsrhc.org.uk) is a vital resource on clinical guidelines in this area and its latest guidance on emergency contraception was published in August this year (2011).²

CONCLUSION

While the IUD is the most effective form of emergency contraception, many women will choose not to have this method, perhaps because of the risks of insertion or because it is a more invasive procedure. However, it is important that women have access to all the information they need so that they can make an informed decision from the choices available.

A consultation for emergency contraception is a valuable opportunity to discuss safer sex, sexually transmitted infections and partner screening, as well as ensuring that women have contraception they are happy with, and use effectively to reduce the need for emergency contraception.

REFERENCES

1. Faculty of Sexual and Reproductive Health Care. (2009) UK Medical Eligibility Criteria for Contraceptive Use. 2009. www.fsrh.org/pages/clinical_guidance.asp

2. Faculty of Sexual and Reproductive Health Care Clinical Effectiveness Unit. Emergency contraception guidance 2011. www.fsrh.org/pages/clinical_guidance.asp

3. Faculty of Family Planning and Reproductive Healthcare Clinical Effectiveness Unit. FFPRHC Guidance: Emergency contraception. J Fam Plann Reprod Health Care. 2006;32(2):121-128

4. Faculty of Sexual and Reproductive Health Care Clinical Effectiveness Unit. Quick starting Contraception 2010. www.fsrh.org/pages/clinical_guidance.asp

5. Faculty of Sexual and Reproductive Health Care Clinical Effectiveness Unit Faculty Statement Levonelle (R) and the use of liver enzyme inducing drugs 2006 www.fsrh.org/pages/clinical_guidance.asp

6. HRA Pharma UK Ltd. EllaOne 30mg: Summary of Product Characteristics 2010

7. Glasier AF, Cameron ST, Fine PM, et al.(2010). Ulipristal acetate versus levonorgestrel for emergency contraception: a randomised non-inferiority trial and meta-analysis. The Lancet 2010;375:555-562

8. Faculty of Sexual and Reproductive Health Care Clinical Effectiveness Unit. Faculty Statement Ulipristal acetate (ellaOne(R)) 2009 www.fsrh.org/pages/clinical_guidance.asp

9. Clinical Knowledge Summaries. Contraception - Management. Available at: http://www.cks.nhs.uk/contraception/management/quick_answers/scenario_combined_oral_contraceptive_coc/drug_interactions/liver_enzyme_inducing_drugs

Websites accessed November 2011.