Paracetamol is a good form of pain relief and is often used by women who are pregnant or breastfeeding without causing any problems.
BSR guidelines advise intermittent use by pregnant women if possible to reduce an increased risk of childhood asthma found in some but not all research studies.
Most women can take the usual dose, even during pregnancy, but if your liver or kidneys aren't working properly you may be told to take a lower dose.
Non-steroidal anti-inflammatory drugs (NSAIDs)
NSAIDs include aspirin, naproxen, meloxicam, etodolac, ibuprofen and indometacin. They may reduce the amount of fluid in the womb surrounding the baby, but they don’t affect the baby.
Some studies suggest that taking NSAIDs may make it more difficult to get pregnant and that they may increase the risk of miscarriage if taken around the time of conception. BSR guidelines advise cautious use of these drugs in early pregnancy.
It's best to use the lowest dose of NSAIDs you can, and your doctor will advise you to stop them completely after 32 weeks of pregnancy. When babies are born a blood vessel in their heart closes, which redirects the baby's blood to allow it to get oxygen from its lungs, rather than the placenta.
But large doses of NSAIDs taken towards the end of pregnancy may cause this blood vessel in the baby's heart to close early, while the baby is still in the womb rather than at birth. This problem usually resolves itself completely if the NSAIDs are stopped.
NSAIDs might also be stopped during delivery as they can prolong the labour and cause excessive bleeding. If you have lupus or antiphospholipid syndrome (APS) you may need to take low-dose aspirin (usually 75 to 150 mg per day) throughout pregnancy, especially if you've had previous miscarriages.
Low-dose aspirin doesn't affect early pregnancy, the development of the blood vessel in the baby's heart later in pregnancy or delivery as described for NSAIDs above.
Most NSAIDs don't enter the breast milk in large quantities, but high-dose aspirin (300 mg or more per day) should be avoided while breastfeeding. You should talk to your doctor about what is best for you and your baby.