Malarone
(Date: September 2017. 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?
Malarone® contains a combination of two different anti-malarial medicines called atovaquone and proguanil. It is used to:
• prevent malaria infection (for example, before travelling to a part of the world where the chance of being infected with malaria is high)
• treat a person who has been infected with malaria
Malaria is a serious illness that is spread by mosquito bites and can result in death. Malaria infection in pregnancy can be dangerous to the health of both mother and baby. Pregnant women are therefore advised to avoid travelling to areas where there is a risk of catching malaria. If you are pregnant or planning a pregnancy and cannot avoid travelling to a high risk malaria area, ask your doctor for advice as soon as possible. You may need to start taking an antimalarial medicine a few weeks before you travel. Your doctor is the best person to help you decide what is right for you and your baby.
Is it safe to use malarone in pregnancy?
If you are travelling to certain regions you may be specifically advised to take Malarone. This is because in some areas, other anti-malarial medicines are ineffective because the malaria parasite has developed resistance to them. You should not avoid taking malarone just because you are pregnant. The risk of harm to you and your baby from malaria is likely to be far greater than any potential risk from taking malarone.
No antimalarial medicine is 100% effective and it is very important that you also reduce the chance of being bitten by using insect repellents, mosquito nets, and covering as much skin as possible with clothing, particularly between dawn and dusk. Please read our bumps leaflets on insect repellents and malaria for more information.
What if I have already taken malarone during pregnancy?
It is always a good idea to let your doctor know that you are pregnant if you have taken any medicines in case you need any additional monitoring or treatment.
This leaflet summarises the scientific studies relating to the effects of malarone on a baby in the womb.
Can use of malarone 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.
Studies of approximately 315 women who used malarone in the first trimester of pregnancy do not suggest that their babies had a higher chance of birth defects than babies not exposed in the womb to malarone. Larger, well-designed studies are ideally required to confirm this finding.
Can use of malarone in pregnancy cause miscarriage?
A small study of 165 women taking malarone suggested that they did not have a higher chance of miscarriage than women in the background population. This finding needs to be confirmed with further research.
Can use of malarone in pregnancy cause stillbirth?
No studies have investigated the chance of stillbirth in women taking malarone in pregnancy.
Can use of malarone in pregnancy cause preterm birth or my baby to be small at birth (low birth weight)?
One small study showed that women with malaria treated with malarone were no more likely to have a preterm birth or a baby with a low birth weight than women with malaria treated with a different medicine. Larger numbers of women need to be studied to confirm these findings.
Can taking malarone in pregnancy cause learning or 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.
A small study of 17 toddlers exposed in the womb to malarone showed that their development at one year old did not differ from that of toddlers exposed in the womb to other medicines to treat malaria. Further larger studies that also continue to assess children as they get older are required to confirm that exposure in the womb to malarone has no effects on learning and behavior.
Will my baby need extra monitoring during pregnancy?
As part of their routine antenatal care most women will be offered a scan at around 20 weeks of pregnancy to look for birth defects and to check the baby’s growth.
Taking malarone during pregnancy is not expected to cause any problems that would require extra monitoring of your baby. However, if you have been infected with malaria during your pregnancy your doctor may wish to monitor your pregnancy more closely.
Are there any risks to my baby if the father has used malarone?
We would not expect any increased risk to your baby if the father used malarone before or around the time you became pregnant.
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.
General information
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.

www.medicinesinpregnancy.org