Pregnancy, breastfeeding and fertility while taking lithium

Lithium may be taken in pregnancy if needed. However, there's a small chance that it may affect how your baby's heart develops in the early stages of pregnancy (the first 12 weeks). After 12 weeks, there is less risk.

You may need to continue taking lithium or change to a different medicine during pregnancy, to remain well.

Speak to your doctor or specialist if you're planning a pregnancy or become pregnant. They'll want to review your medicine to check that it's the best treatment option for you and your baby.

Do not stop taking your medicine unless your doctor tells you to as this may affect your mental health.

If your doctor, midwife or health visitor says your baby is healthy, you can take lithium while breastfeeding, but this is usually after specialist advice.

Speak to your doctor or specialist if you are planning to breastfeed. They'll help you decide the best option for you and your baby. Your lithium dose may need to be reduced after giving birth and your baby may need extra blood tests.

Do not stop taking your medicine unless you're told to do so as this may affect your mental health. Breastfeeding will also benefit both you and your baby.

The amount of lithium that passes into breast milk can range from small to quite large amounts. Lithium is not generally linked with side effects in breastfed babies, although it has caused side effects in a few babies.

It's important to look out for any side effects in your baby. They are more likely if your baby has an infection or becomes dehydrated.

• is not feeding as well as usual or putting on weight as you would expect
• seems unusually sleepy or tired
• has diarrhoea or is being sick
• is showing other signs of an infection (for example is irritable, has a high temperature or seems clammy or sweaty)
• is showing signs of dehydration (not drinking as much or producing as many wet nappies)

There is no evidence that lithium affects female fertility. However, there’s a small chance it can reduce sperm count in men.

Speak to your doctor if you're trying for a baby.

Tell your doctor if you're:

• trying to get pregnant
• pregnant
• breastfeeding