Epilepsy - Contraception / Pregnancy Issues

Contraception

Some antiepilepsy medicines have a side-effect of increasing the speed in which some contraceptive pills and injections are processed by the liver. (These medicines are known as liver enzyme inducers as they speed up certain processes in the liver cells.)

The following antiepilepsy medicines are liver enzyme inducers:

• carbamazepine
• oxcarbazepine
• phenobarbital
• phenytoin
• primidone
• topiramate

The other antiepilepsy medicines , including sodium valproate, lamotrigine and ethosuximide, are not liver enzyme inducers. If you are taking an antiepilepsy medicine which is not a liver enzyme inducer then your contraceptive choices, doses, etc, are then usually the same as for any other women. (However, see below about lamotrigine.) See separate leaflet called 'Contraceptive Choices' for details of the options.

However, if you are taking an antiepilepsy medicine that is a liver enzyme inducer, then the following is recommended:

• If you take the combined oral contraceptive pill (COCP) - the dose of the oestrogen part needs to be at least 50 micrograms, which is more than the usual dose. However, it is usually preferable to use an alternative contraception, if possible.
• The progestogen-only pill is not recommended.
• Progestogen implants are not recommended.
• The combined transdermal contraceptive patch is not recommended.
• If you use emergency contraception tablets - the initial dose of levonorgestrel should be increased to 3 mg (you will need to take two tablets instead of one).
• The progestogen injection called Depo-provera® does not interfere with liver enzyme inducing drugs. You can continue with your usual injection every twelve weeks.

Special consideration - lamotrigine and the pill

There is some evidence that the COCP (the 'pill') may interact with lamotrigine (Lamictal®) in some women. Lamotrigine is an antiepilepsy medicine. It is not a liver enzyme inducer but may interact with the COCP in another way. The interaction may work 'both ways'. That is, the lamotrigine may make the 'pill' less effective and the 'pill' may also make the lamotrigine less effective and increase your risk of seizures. Therefore, the doses of both medications may need to be adjusted.

It may be preferable to consider an alternative method of contraception if you are taking lamotrigine and need to use contraception.

Note: for reliable contraception, it is best to seek advice from a doctor or nurse. They will be able to tell you if your epilepsy treatment affects any methods of contraception.

Pregnancy

Most pregnant women with epilepsy have a normal pregnancy and childbirth.

The frequency of seizures may increase in pregnancy in around 3 out of 10 women. For women with epilepsy, the risk of complications during pregnancy and labour is slightly higher than for women without epilepsy. The small increase in risk is due to the small risk of harm coming to a baby if you have a serious seizure whilst pregnant, and also the small risk of harm to an unborn baby from antiepilepsy medicines (discussed further below).

Note: the risk of complications to your unborn baby is greater with a seizure compared to the risk of not taking your epilepsy medication.

Before becoming pregnant

Before becoming pregnant, it is best to seek advice from your doctor or epilepsy nurse. You should be seen by an epilepsy expert to discuss your treatment during your pregnancy in detail. The potential risks and benefits of adjusting your treatment, if necessary, can be discussed. If your pregnancy is planned carefully then any risk of complications may be minimised.

Most of the advice is the same as for any other woman who is planning a pregnancy. (See separate leaflet called 'Planning to Become Pregnant?'. For example, advice on diet, smoking, alcohol, avoiding infection, etc.)

However, you may be recommended to:

• Stop or reduce the dose of your treatment before you become pregnant if your seizures have been well controlled. However, deciding to come off antiepilepsy medication can be a difficult decision. Factors such as the type of epilepsy that you have can be important. For example, if you have the type of epilepsy that causes severe tonic-clonic seizures, there is a risk that you could have a severe seizure when you are pregnant if you stop your medication.
• Change to taking a different medication which is less likely to cause harm to the fetus (depending on the medication you are already taking).
• Take folic acid at a strength of 5 mg a day. This should ideally be taken before you become pregnant and continued until you are 12 weeks pregnant. Although folic acid is recommended for all women who are pregnant, the dose for women taking antiepilepsy medicines is higher than usual. Taking folic acid has been shown to reduce the risk of having a baby born with a spinal cord problem such as spina bifida.
• Notify your pregnancy to the UK Epilepsy and Pregnancy Register (www.epilepsyandpregnancy.co.uk). This is to allow information to be gathered to improve the future management of pregnant women with epilepsy.

Risk from antiepilepsy medicines

If you take antiepilepsy medicines when you are pregnant, you have a very small increased risk of having a baby with a birth defect. The most common birth defects that occur are neural tube defects (such as spina bifida), facial defects, congenital heart defects and hypospadias (a defect of the penis).

• Overall, about 2 in 100 pregnant women who take one antiepilepsy medicine have a baby with a birth defect. The risk rises to about 6-7 in 100 when taking two antiepilepsy medicines.
• However, the risks from different medicines can vary. For example, the risk for sodium valproate is about 7 in 100, whereas the risk for carbamazepine is about 2 in 100 and the risk for lamotrigine is about 3 in 100. Therefore, if possible, sodium valproate is not prescribed to women who may become pregnant.
• Taking folic acid 5 mg daily (as discussed above) is thought to reduce the risk from antiepilepsy medicines during pregnancy.
• Pregnant women who are taking antiepilepsy medicines are usually offered a high-resolution ultrasound scan to screen for birth defects at 18-20 weeks' pregnancy. However, earlier scanning may allow major birth defects to be detected sooner.
• If you have an unplanned pregnancy, you must not stop your antiepilepsy medicine without advice, as doing so may put you at risk of having a seizure. However, see a doctor as soon as possible and start taking folic acid 5 mg daily straight away.

Breastfeeding

Breastfeeding for most women taking antiepilepsy medicines is generally safe. Your doctor, midwife or health visitor can advise you in more detail.

What are the risks that your child will also have epilepsy?

In general, the probability is low that a child born to a parent with epilepsy will also have epilepsy. However, it can partly depend on your family history, as some types of epilepsy run in families. Therefore, genetic counselling may be an option to consider if you or your partner has epilepsy and also a family history of epilepsy.

Further information

Epilepsy Action

New Anstey House, Gateway Drive, Leeds, LS19 7XY
Helpline: 0808 800 5050 Web: www.epilepsy.org.uk

National Society For Epilepsy

Chesham Lane, Chalfont St Peter, Gerrards Cross, Bucks, SL9 0RJ
Helpline: 01494 601 400 Web: www.epilepsynse.org.uk

Epilepsy Scotland

48 Govan Road, Glasgow, Scotland, G51 1JL
Helpline: 0808 800 2200 Web: www.epilepsyscotland.org.uk

Epilepsy Wales

PO Box 4168, Cardiff, CF14 0WZ
Helpline: 08457 413 774 Web: www.epilepsy-wales.co.uk

References

• Epilepsy, Clinical Knowledge Summaries (June 2009)
• Bromley RL, Baker GA, Meador KJ; Cognitive abilities and behaviour of children exposed to antiepileptic drugs in utero. Curr Opin Neurol. 2009 Apr;22(2):162-6. [abstract]
• No authors listed; Intrauterine devices: an effective alternative to oral hormonal contraception. Prescrire Int. 2009 Jun;18(101):125-30. [abstract]
• Walker SP, Permezel M, Berkovic SF; The management of epilepsy in pregnancy. BJOG. 2009 May;116(6):758-67. [abstract]
• Burakgazi E, Harden C, Kelly JJ; Contraception for women with epilepsy. Rev Neurol Dis. 2009 Spring;6(2):E62-7. [abstract]