The following information is from The Migraine Trust. It's not a replacement for medical advice from your doctor or midwife. Always discuss any concerns or symptoms with a medical professional who can give specific advice, just for you.

Migraine in pregnancy

Hormonal change in women is a common trigger for those prone to migraine. This is often shown in pregnancy when the sex hormone levels show profound changes which has an effect on whether your migraine get better or worse. Oestrogen sometimes reaches one hundred times the normal level, whilst progesterone levels decrease, rising again towards the end of the pregnancy. However, the fluctuation of levels is not as pronounced as during the non-pregnant state, which may be why migraine often improves during pregnancy. This improvement may also be due to the increased levels of natural pain-killing hormones (endorphins). These are several times higher during pregnancy, and though the relief from migraines they provide might last the whole pregnancy, the levels settle back down after delivery, normally allowing migraine attacks to recur.

However, it is not always the case that your migraine will improve, especially in the early weeks of pregnancy. For some women, migraine can go on unchanged, or more rarely even get worse. During breastfeeding, stable oestrogen levels may be protective against having headache again after pregnancy.

Planning a pregnancy

If you are taking regular medication for your migraine and are planning a pregnancy, you should see your doctor for advice on the management of your migraine before and during pregnancy, after the birth and while you breastfeed.

Migraine without aura in pregnancy

Studies show that migraine without aura improves after the first three months of pregnancy for about 60-70% of women. This is the case especially if your migraine has been linked to your menstrual cycle.

Migraine with aura in pregnancy

If you experience migraine with aura you are more likely to continue to have attacks during your pregnancy. Also if you experience migraine for the first time while you are pregnant it is likely to be with aura.

If you do think you are experiencing migraine for the first time whilst you are pregnant it is important to visit your GP so the causes for your head pain can be found and treated if necessary. Pre-eclampsia and other more serious causes of headache can have symptoms similar to migraine.

Conventional medication and pregnancy

If you are taking any prophylactic (preventive) treatments you should discuss stopping these or switching to a safer alternative with your doctor. It is advisable to take as few drugs as possible in the lowest effective dose and ideally all drug treatments should usually be avoided whilst you are pregnant.

Most of the evidence for the safety of drugs in pregnancy is circumstantial as drugs cannot usually be tested on pregnant or breastfeeding women for ethical reasons. This means the advice regarding drug treatments for migraine in pregnancy will usually err on the side of caution.

During pregnancy and breastfeeding the preferred treatment strategy should always be a non-pharmacological one. Nevertheless, poorly controlled headache can lead to stress, sleep deprivation, depression and poor nutritional intake. Therefore, if non-drug options become inadequate, a considered choice should be made concerning the use of medication, taking into account all the benefits and possible risks, in consultation with your doctor. A general rule should be to aim for the lowest effective dose and the shortest duration of treatment.

The first three months of pregnancy

During the first three months, the symptoms of pregnancy can make your migraine worse. Morning sickness can mean that you feel like eating and drinking less which can cause low blood sugar and dehydration. If you are not careful this can make your migraines worse. You should try to eat small frequent meals and drink frequent small amounts of water to prevent this. This may also help reduce any pregnancy sickness.

After the birth

For some women, migraine returns with the return of their periods. Some mothers find they have a bad attack within a couple of days of giving birth. This may be due to the sudden drop in oestrogen levels after birth. Exhaustion, dehydration, erratic sleep and low blood sugar after giving birth may also play a part.

Migraine and your baby

There is no evidence that migraine (with or without aura) has an effect on the outcome of pregnancy. Migraine does not harm or endanger your baby.

Learn more and get support from The Migraine Trust