(Date of issue: March 2016. Version: 2)
This factsheet has been written for members of the public by the UK Teratology Information Service (UKTIS). UKTIS is a not-for-profit organisation funded by Public Health England on behalf of UK Health Departments. UKTIS has been providing scientific information to health care providers since 1983 on the effects that medicines, recreational drugs and chemicals may have on the developing baby during pregnancy.
What is it?
Morphine is a medicine that is prescribed for severe pain that has not responded to other treatments and in the treatment of narcotic drug addiction. It belongs to a group of medicines called opiates.
Is it safe to use morphine in pregnancy?
There is no yes or no answer to this question. When deciding whether to use morphine during pregnancy it is important to weigh up how necessary morphine is to your health against any possible risks to you or your baby, some of which might depend on how many weeks pregnant you are. Unfortunately there is very little information on use of morphine in pregnancy, and about half of the information that is available is from a single small study of women with narcotic addiction who may have different health issues to women with chronic pain.
It is important to appropriately treat pain in pregnancy. For some women with severe pain, treatment with morphine in pregnancy might be considered to be the best option. Your doctor is the best person to help you decide what is right for you and your baby.
What if I have already used morphine during pregnancy?
If you have taken any medicines it is always a good idea to let your doctor know that you are pregnant so that you can decide together whether you still need the medicines that you are on and to make sure that you are taking the lowest dose that works.
Can using morphine in pregnancy cause my baby to be born with birth defects?
A baby’s body and most internal organs are formed during the first 12 weeks of pregnancy. It is mainly during this time that some medicines are known to cause birth defects.
Only one small study of 70 women who used morphine in early pregnancy has been carried out. The results did not indicate that morphine use in early pregnancy increases the likelihood of birth defects generally, but much larger studies are needed to rule out the possibility of a link with specific defects.
Can using morphine in pregnancy cause miscarriage?
No studies have investigated whether rates of miscarriage are increased in women who use morphine in pregnancy.
Can using morphine in pregnancy cause stillbirth?
A single small study of women who were addicted to narcotic drugs and treated with morphine showed that these women were around twice as likely to experience a stillbirth as women addicted to narcotic drugs who were not treated with morphine. However, the women in this study receiving morphine treatment might have had more severe addiction problems than the untreated women. Other lifestyle factors (such as smoking, alcohol use, and poor nutrition) may be more common in women with severe addiction and may be linked to the increased occurrence of stillbirth. Large studies of women taking morphine to treat pain (not addiction) are therefore required before we can say whether use of morphine in pregnancy increases the risk of stillbirth.
Can taking morphine in pregnancy cause the baby to be small at birth (low birth weight), or preterm birth?
A single small study investigated pregnant women addicted to narcotic drugs who were being treated with morphine. The study found that, on average, babies of morphine-treated women were slightly smaller than babies of women addicted to narcotic drugs not treated with morphine. This was not because these babies were born earlier than those of untreated women. However, the women in this study who received morphine treatment might have had more severe addiction problems than the untreated women. Lifestyle factors (such as smoking, alcohol use and poor nutrition), which can be more common in women with severe addiction, could therefore also have affected the growth of the baby in the womb. Large studies of women taking morphine to treat pain are therefore required before we can say whether use of morphine in pregnancy increases the risk of low birth weight in the baby, or preterm birth.
Can taking morphine in pregnancy cause other health problems in the baby/child?
Withdrawal symptoms at birth
Withdrawal symptoms are thought to occur as the newborn baby’s body has to adapt to no longer getting certain types of medicines through the placenta.
There are case reports in the scientific literature of withdrawal symptoms after birth in babies exposed to morphine in the womb. If you have used morphine regularly in the weeks before delivery, your doctor or midwife might arrange for your baby to be born at a unit that can monitor and, if necessary, treat your baby for withdrawal symptoms.
Learning and behavioural problems in the child
A baby’s brain continues to develop right up until the end of pregnancy. It is therefore possible that taking certain medicines at any stage of pregnancy could have a lasting effect on a child’s learning or behaviour.
There are currently no scientific studies that have examined learning and behaviour in children of women who took morphine during pregnancy. Research into this subject is therefore required.
Will my baby need extra monitoring during pregnancy or after delivery?
Most women will be offered a scan at around 20 weeks of pregnancy to look for birth defects as part of their routine antenatal care. Using morphine in pregnancy is not expected to cause problems that would require extra monitoring of your baby during pregnancy. However, women with some of the underlying conditions that morphine can be used to treat might be more closely monitored to ensure that their baby is growing and developing as expected.
Babies born to women who have taken morphine in late pregnancy might be closely monitored after birth to ensure that they are not experiencing withdrawal symptoms.
Are there any risks to my baby if the father has used morphine?
No studies have specifically investigated whether morphine used by the father can harm the baby through effects on the sperm, however most experts agree that this is very unlikely. More research on the effects of medicine use in men around the time of conception is needed.
Who can I talk to if I have questions?
If you have any questions regarding the information in this leaflet please discuss them with your health care provider. They can access more detailed medical and scientific information from www.uktis.org.
Up to 1 out of every 5 pregnancies ends in a miscarriage, and 1 in 40 babies are born with a birth defect. These are referred to as the background population risks. They describe the chance of these events happening for any pregnancy before taking factors such as the mother’s health during pregnancy, her lifestyle, medicines she takes and the genetic make up of her and the baby’s father into account.
Medicines use in pregnancy
Most medicines used by the mother will cross the placenta and reach the baby. Sometimes this may have beneficial effects for the baby. There are, however, some medicines that can harm a baby’s normal development. How a medicine affects a baby may depend on the stage of pregnancy when the medicine is taken. If you are on regular medication you should discuss these effects with your doctor/health care team before becoming pregnant.
If a new medicine is suggested for you during pregnancy, please ensure the doctor or health care professional treating you is aware of your pregnancy.
When deciding whether or not to use a medicine in pregnancy you need to weigh up how the medicine might improve your and/or your unborn baby’s health against any possible problems that the drug may cause. Our bumps leaflets are written to provide you with a summary of what is known about use of a specific medicine in pregnancy so that you can decide together with your health care provider what is best for you and your baby.
Every pregnancy is unique. The decision to start, stop, continue or change a prescribed medicine before or during pregnancy should be made in consultation with your health care provider. It is very helpful if you can record all your medication taken in pregnancy in your hand held maternity records.