Guidance on prescribing valproate for bipolar disorder in women of child-bearing potential

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1 Guidance on prescribing valproate for bipolar disorder in women of child-bearing potential Background Valproate is prescribed for mood stabilisation in bipolar disorder; however it is wellestablished as both teratogenic and causing developmental delay. All the data for valproate and its teratogenic risk come from its use as an antiepileptic, however in 2006 NICE 1 produced guidance for bipolar disorder which recommended valproate should not be routinely prescribed for women of child bearing age (See below for guidance). The background rate of malformations is 2-3% (i.e. 1 in 40 babies are born with malformations) and the risk of malformation with valproate is quoted as 10% after the first trimester. Developmental delay was shown in the offspring (age 6-16) exposed to valproate during the pregnancy and they were found to be more likely to have an IQ below 69 and a poorer memory compared to exposure to other antiepileptics or those with no exposure to antiepileptics. It has been shown that exposure to valproate in utero may lead to a higher than expected incidence of education needs statements. There is also an association between valproate and polycystic ovary syndrome, which may have an effect on fertility. This effect may be due to weight gain associated with valproate. In November 2006 NICE 1 produced guidance for bipolar disorder and the guidance recommended that:- Valproate should not be prescribed routinely for women of child-bearing potential. If no effective alternative to valproate can be identified, adequate contraception should be used, and the risks of taking valproate during pregnancy should be explained. Valproate should not be prescribed for young women with bipolar disorder who are younger than 18 years because of the risk of polycystic ovary syndrome and unplanned pregnancy in this age group. Contraception and the risks of pregnancy (including the risks of relapse, damage to the fetus, and the risks associated with stopping or changing medication) should be discussed with all women of child-bearing potential, regardless of whether they are planning a pregnancy. They should be encouraged to discuss pregnancy plans with their doctor. 1

2 Guidance to minimise the risks if considering prescribing valproate in women of child-bearing potential The risk of unplanned pregnancy in this general population is approximately 50%. However, women with a diagnosis of bipolar disorder may become sexually disinhibited and therefore the rates of pregnancy may be higher than 50% in this patient group. Therefore the risks of using valproate in women of child-bearing potential must be discussed prior to prescribing. This should include: The increased risk of teratogenic effects and developmental delay, The risk of polycystic ovary syndrome (if under 18 years of age) The risk of not treating bipolar disorder. If there is no alternative to valproate in women of child-bearing potential, the following should occur: The patient should be informed of the increased risk to the fetus and the child s intellectual development, should a pregnancy occur. The need for effective contraception must be discussed. Folic acid supplement should be prescribed at a dose of 5mg per day, if there is concern about unplanned pregnancies. The need to contact their doctor as soon as possible if, planning to become pregnant, think they might be pregnant or are pregnant, while on valproate. A patient information leaflet, incorporating a consent form, on possible valproate side-effects in women of child-bearing potential (appendix 1) is available. A completed consent form must be put in the patient s notes and a copy given to the patient. The leaflet and consent form is available from the Trust s website: All discussions should be clearly documented in the patient s notes. If a pregnancy does occur, advice from a specialist should be sought as soon as possible. The NICE guidance for bipolar disorder should also be referred to. References 1. NICE. Clinical Guidance 38. Bipolar disorder. Nov Patient information leaflet for Epilim. Sanofi Aventis 04/ Psychotrophic Drug Directory Bazire, HealthComm 4. The Maudsley Prescribing Guidelines. 9 th Edition. Taylor. Informa Healthcare If you require this document in another format such as large print or audio please contact the Communications Team on or info@sussexpartnership.nhs.uk 2

3 Appendix 1 Patient information leaflet on possible valproate side-effects if you become pregnant (incorporating a consent form) Before you decide to start taking valproate your doctor should discuss with you the possible problems when it is taken in pregnancy. Effects of valproate on pregnancy Women taking valproate (including semi-sodium valproate (Depakote ) and sodium valproate (Epilim, Episenta and Convulex )) during pregnancy have a higher risk of having a child with an abnormality. This risk is increased from 2-3 in 100 to 10 in 100, therefore you have a 3-5 times greater risk of a child with an abnormality. The main concern is spina bifida, which is an abnormality of the spinal cord. Women who take valproate during pregnancy may be more likely to have a baby with spina bifida. Taking 5mg of folic acid each day as soon as you stop contraception may lower the risk of having a baby with spina bifida. There is also an increased risk of other birth abnormalities including: Head and face deformities including cleft palate (a gap or depression in the lip) Deformities of the bones, including hip dislocation Malformations of the arms and legs Deformities of the tube from the bladder to the penis Heart and blood vessel malformations, including heart defect and defects of the lining of the spinal cord. These other defects can usually be detected in the first 3 months of the pregnancy using routine antenatal screening blood tests and ultrasound scans. Pregnant mothers who take valproate may have babies with blood clotting problems, such as bleeding more easily or for longer periods. This may appear as bruising or bleeding, which takes a long time to stop. Some babies born to mothers who take valproate during pregnancy may develop less quickly than normal. These children may require additional support at school. If you require this document in another format such as large print or audio or in another community language, please contact the Communications Team on or info@sussexpartnership.nhs.uk 3

4 If you decide to take valproate you should use an effective method of contraception and talk to your doctor before planning a pregnancy. Valproate has no effect on how well the oral contraceptive pill works and they can safely be taken together. Women who get pregnant If you are planning to become pregnant, think you may be pregnant or become pregnant, you must tell your doctor straight away. Your doctor will give you appropriate counselling and may suggest changes to your treatment or the dose of your medication. He or she will also want to regularly check your progress while you are pregnant. It is extremely important that you discuss your treatment with your doctor well before you become pregnant. Please read and complete the attached consent form below. If you would like more time to think about the information given to you today or would like to discuss it with a partner, relative or friend before making a decision, please let your doctor know. Consent given/withheld form for use when considering the use of valproate in women of child-bearing potential Initial each box if you agree with the statement. I confirm that: Doctor. has explained the benefits and possible side-effects, including the risks to an unborn baby, of using valproate to treat bipolar disorder and I have understood the explanation. Doctor. has discussed the need for me to use effective contraception (e.g. the pill or coil) while taking valproate. I understand that if I wish to get pregnant I need to discuss the benefits and risks of continuing valproate treatment with my doctor before I stop using contraception. I have been given a patient medication leaflet on valproate. 4

5 Doctor.. has discussed other treatment options with me, and also the consequences of not using this medication. Treatment options discussed include: I have had enough time to consider my decision and to ask questions. I understand that the valproate is being prescribed within its licence (semisodium valproate) but there are risks to the unborn baby if I become pregnant/outside its licensed indication (sodium valproate) and there are risks to the unborn child if I become pregnant*. I understand I can withdraw my consent at any time and I will inform my doctor if I wish to stop taking valproate. I consent to being treated with valproate*. or I do not consent to be treated with valproate*. Signed:. (patient) (printed name) Date:.. Signed: (doctor) (printed name) Date:.. ( title) *Delete as appropriate Once completed the original should go in the patient s notes and a copy provided for the patient. Published: March 2010 Review date: March 2013 (or sooner if relevant national advice is published) 5