7. Emergency contraception:

Abbreviations:

EC.          Emergency contraception.

FFP.        Faculty of Family Planning. Now the Faculty of Sexual and Reproductive Healthcare.

FSRH:     Faculty of Sexual and Reproductive Healthcare.

LNG.        Levonorgestrel.

IUCD.       Intra-uterine contraceptive device.

UPSI.       Unprotected sexual intercourse.

Suggested reading:

There is an excellent guidance paper "Emergency Contraception" from 2011 on the on the FSRH's web site. 

It includes everything you might be asked in the examination. 

I strongly recommend that you read it.  

Hot from the press.

We are all familiar with levonorgestrel and the copper IUS for EC.

Ulipristal, a selective progesterone receptor modulator was licensed for EC in 2009.

It seems to be at least as effective as levonorgestrel and can be used for up to 120 hours after UPSI.

See MCQ paper 12, question 30 for more details.

Background.

This question and answer were written a couple of years ago with periodic updates, hence the residual reference to PC4. 

This was the original, oestrogen-based EC and taking PC4 was also known as the YUZPE method. 

I have left the reference as it might still be in the College database and you may come across it in older books. 

About 20% of women experienced vomiting and had to have repeat doses. 

The comparable figure for LNG is 1%.  

PC4 was superseded by LNG and removed from the market by the manufacturer in October 2001.

How does EC work?

Does anybody care? 

Well, there are plenty of women who are happy to use contraception, including EC, but are opposed to abortion. 

If you believe that life starts with fertilisation, then EC that works by preventing implantation would be unacceptable.

The evidence is that LNG works mainly by preventing ovulation, so it would be acceptable. 

The IUCD mainly works by altering sperm transport.

But it may have an effect on the endometrium preventing implantation.

So some would find it unacceptable. 

If EC causes abortion, even is a minority of cases, you would need to fill in all of the related "notification of abortion" paperwork. 

However, there was a legal ruling in 2002 that deemed that pregnancy starts with implantation, not fertilisation, which got round the problem. 

The abortion issue does restrict the use of the IUCD.

It should not be used after implantation.

This is likely to occur within 5 days of ovulation.

So the IUCD cannot be used later than 5 days from the time of ovulation. 

In general, this means not more than 5 days from the time of UPSI, 

However, if you are sure of the time of ovulation, the IUCD could be used up to 5 days after this likely time.

PC4 was given as 2 doses, 12 hours apart – I don’t know what science there was to support this. 

When first used, LNG was given as two doses of 0.75 mg. twelve hours apart. 

A BMJ editorial (BMJ 2003: 326:775-776)  recommended a single 1.5 mg. dose of LNG. 

Tests had shown it to be as effective as the double dose (pregnancy rates of 1.5% and 1.8% respectively).

The hope was this would overcome the problem of the second dose being forgotten. 

It is available as “Levonelle One Step” and “Levonelle 1500”. (The 0.75 mg. tablets were “Levonelle 2”.) 

Research evidence indicates that the 72 hour limit is too conservative and that LNG is still effective up to 120 hours. 

Efficacy obviously diminishes with time.

But it is mostly determined by the potential fertility of the couple and the proximity of the act of UPSI to the time of ovulation. 

Liver enzyme-inducing drugs necessitate an increase in the dose. 

Basically, the woman takes an extra pill. 

In the days of 0.75 mg. tablets taken twice, she took a total of 2.25 mg. 

With the 1.5mg tablet, she takes 3mg.

The BMJ article pointed out that these women are at particular risk of STD, especially chlamydia.

With rates of ~ 5%, so this should be taken into consideration. 

The FFP paper makes the same point and stresses that the younger the woman, the greater the risk.

The incidence of chlamydia in General Practice is 8% in women under 20, compared with 1.4% of women over 30.

A sexual history should be taken from all women and screening done for high risk groups.

Screening would be appropriate for:

    a woman of 18 with multiple partners,

    but not a woman of 45 who has been in a stable marriage for 25 years and needs EC because of a burst condom. 

The risk of infection is a particular issue in relation to the IUCD as EC. 

The FFP paper cites the incidence of pelvic infection in association with use of the IUCD as 1.6 per 1,000 women years. 

The time of greatest risk is the first 20 days after insertion, when it is six times higher that at other times. 

The low risk of pelvic infection means that you do not routinely prescribe antibiotics when inserting the IUCD. 

For a woman at increased risk of infection (younger, casual encounter, more than one partner in the past year etc.) screening should be done.

Antibiotics can be prescribed when the IUCD is inserted.

The author of the BMJ  also stressed the need for continuing contraception.

There was a real possibility of conception occurring while awaiting the next period.

This was reiterated in the FFP paper.

The copper IUCD is almost 100% effective if inserted before implantation, which occurs about 5 days after ovulation.

The progesterone loaded IUCD in not yet used for emergency contraception and at least one pregnancy has been recorded.

As the copper IUCD is so effective and a lot cheaper, the progesterone IUCD will need further evaluation before its place can be determined.

Mifepristone is effective as EC, perhaps even more so than LNG.

It is not yet licensed.

Emergency contraception is being made more easily available.

The legal status of LNG as emergency contraception was changed from a prescription-only medicine to a pharmacy medicine in January 01.

It can now be bought from chemists without a prescription. 

Dispensing rights are likely to be widened to include Practice Nurses, School Nurses etc. 

Perhaps we will see dispensers in pubs and schools!

A “Patient Group Direction” is a form of protocol authorising nurses and others who are not doctors to provide medicines.

Mostly they will be used by Primary Care Trusts.

The "Direction" needs to spell out the type of patient to whom it applies, criteria for exclusion, indications for referral to a doctor etc.

Key points.

The copper IUCD is the most effective method of emergency contraception.

LNG 1.5 mg. as a single dose is as effective as 0.75 mg. as a double dose with a 12 hour interval.

LNG is effective for up to 120 hours, so the current limit of 72 hours needs to be updated.

~ 5% of women seeking emergency contraception have a STD, especially chlamydia.

Continuing contraception is mandatory.

PC4 has been withdrawn.