This sheet is about having mpox in a pregnancy or while breastfeeding. This information is based on available published literature. It should not take the place of medical care and advice from your healthcare provider.

What is mpox?

Mpox (which used to be called monkeypox) is an illness caused by the mpox virus (MPXV). MPXV belongs to a group of viruses called orthopoxviruses.

Symptoms of mpox can begin 5 to 21 days after being exposed to the virus, but most people start having symptoms in 7 to 14 days. The first symptoms to appear include: fever, headache, muscle aches, backache, swollen lymph nodes (“glands”), chills, and exhaustion (being very tired). A few days after these symptoms start, a skin rash appears on the body, often starting near the genitals or on the face. The rash causes bumps and sores that can be itchy and painful and that gradually turn into scabs that fall off. In most people, the illness lasts 2 to 4 weeks before clearing up on its own. However, for some people, mpox can cause severe illness and even death. Women who are pregnant are more likely to have more severe illness than others.

How do you get mpox?

Mpox spreads from person to person through body fluids. This can include direct contact with the skin sores or scabs of an infected person, from the fluids that come from these sores (such as on clothing or bedding), or through saliva and respiratory droplets (such as kissing or being in close contact with someone with mpox when they breathe, talk, cough, or sneeze). Mpox can also spread through intimate or sexual contact with a person with mpox.

How can I protect my pregnancy from mpox?

The Centers for Disease Control and Prevention (CDC) recommends the following:

• Avoid close or intimate contact with people who have a rash that looks like mpox.
• Avoid animals that can carry the virus.
• Do not use objects or materials a person with mpox has used.
• Wash your hands well and often

A vaccine for mpox is available and recommended for some groups of people. More information can be found on the CDC’s website on mpox vaccination here: https://www.cdc.gov/poxvirus/mpox/vaccines/vaccine-recommendations.html.

What should I do if I think I have been infected with mpox?

It is important that you seek medical attention if you think you have mpox. Treatment for mpox will depend on your symptoms. The CDC has recommended that women who are pregnant, recently pregnant, or breastfeeding, who need treatment for mpox, should be offered antiviral medication. There is an increased risk of more severe illness in women who are pregnant and have mpox. Be sure to talk to your healthcare provider about what mpox treatment is best for you.

I have mpox. Can it make it harder for me to become pregnant?

It is not known if having mpox can make it harder to get pregnant. There are no official recommendations to wait to get pregnant after having mpox. However, Mpox can be passed to a fetus during pregnancy. Talk with your healthcare provider about your plans to try and get pregnant.

Does having mpox increase the chance for miscarriage?

Miscarriage can occur in any pregnancy. It is not known if having mpox can increase the chance of miscarriage. Infection during pregnancy with other viruses related to mpox (such as smallpox) has been found to increase the chance of miscarriage.

Does having mpox increase the chance of birth defects?

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. It is not known if having mpox can increase the chance of birth defects.

Fever is a possible symptom of mpox. A high fever in the first trimester can increase the chance of certain birth defects. Acetaminophen is usually recommended to reduce fever in pregnancy. If you have a fever, talk with your healthcare provider about how to treat it during pregnancy. For more information about fever and pregnancy, see the MotherToBaby fact sheet about hyperthermia at https://mothertobaby.org/fact-sheets/hyperthermia-pregnancy/ and a fact sheet on acetaminophen here: https://mothertobaby.org/fact-sheets/acetaminophen-pregnancy/.

Would having mpox increase the chance of other pregnancy-related problems?

Mpox infection has not been well-studied in pregnancy. There is 1 case report of a stillbirth and 1 case report of a preterm delivery (birth before week 37) after infection with mpox during pregnancy. In both cases, the babies also had signs of mpox infection. Infection during pregnancy with other viruses related to mpox (such as smallpox) has been found to increase the chance of stillbirth and preterm delivery. It is not known if mpox infection can cause other pregnancy-related problems, such as low birth weight (weighing less than 5 pounds, 8 ounces (2500 grams) at birth).

Can the virus that causes mpox pass to the baby during pregnancy or at the time of delivery?

When a woman is pregnant and passes an infection to the fetus, it is called vertical transmission. Vertical transmission can happen at any time in pregnancy but is more likely to happen when someone gets the infection close to delivery.

Vertical transmission has been reported with mpox infection in pregnancy. In the 2 case reports described above, the mpox virus passed to the babies during pregnancy and caused symptoms that included skin sores. It is not known how often a mpox infection might pass to a fetus during pregnancy or at the time of delivery, or how likely it is to cause problems during pregnancy or after birth.

Does having mpox in pregnancy affect future behavior or learning for the child?

Studies have not been done to learn if having mpox in pregnancy can increase the chance of behavior or learning issues for the child.

Breastfeeding while I have mpox:

It is not known if the virus that causes mpox gets into breast milk, or if having skin sores on or near the nipples or breasts could cause the virus to get into milk that is expressed or pumped. However, the virus can be passed to an uninfected infant through close contact with a person who is infected (such as holding the baby to breastfeed). If you have mpox, talk with your baby’s healthcare provider about the best way to feed your baby until you recover. Be sure to talk to your healthcare provider about all your breastfeeding questions.

If a man has mpox, can it affect fertility or increase the chance of birth defects?

Studies have not been done to see if having mpox could affect a man’s fertility (ability to get a woman pregnant) or increase the chance of birth defects above the background risk. Mpox can spread through intimate or sexual contact. Talk with your healthcare provider as soon as possible if you or your partner has mpox. For general information on paternal exposures, please see the MotherToBaby fact sheet at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

Please click here to view references.

This sheet is about exposure to natalizumab in pregnancy and while breastfeeding. This information is based on published research studies. It should not take the place of medical care and advice from your healthcare provider. 

What is natalizumab? 

Natalizumab is a monoclonal antibody given by injection (shot). Natalizumab has been used to treat severe multiple sclerosis (MS) or Crohn’s disease when other medications have not worked. Natalizumab is sold under the brand name Tysabri®. 

Sometimes when women find out they are pregnant, they think about changing how they take their medication or stopping their medication altogether. However, it is important to talk with your healthcare providers before making any changes to how you take your medication. Available information suggests that stopping natalizumab before pregnancy may increase the chance of a return of symptoms (relapse), while continuing treatment during pregnancy was associated with fewer relapses and lower recurrence rates. It is important that you talk with your healthcare providers about your treatment options before pregnancy, or as soon as you learn that you are pregnant. They can go over the best way to treat your condition before, during, and after pregnancy. 

MotherToBaby has fact sheets on MS https://mothertobaby.org/fact-sheets/multiple-sclerosis/ and inflammatory bowel disease (including Crohn’s disease) https://mothertobaby.org/fact-sheets/inflammatory-bowel-disease-pregnancy/.  

I am taking natalizumab, but I would like to stop taking it before getting pregnant. How long does the drug stay in my body? 

The time it takes the body to metabolize (process) medication is not the same for everyone. In healthy non-pregnant adults, it could take up to 70 days (a little over 2 months), on average, for most of the natalizumab to be gone from the body. 

I take natalizumab. Can it make it harder for me to get pregnant?  

Studies have not been done in humans to see if natalizumab can make it harder to get pregnant.  

Does taking natalizumab increase the chance of miscarriage?  

Miscarriage is common and can occur in any pregnancy for many different reasons. Information on over 500 pregnancies does not suggest an increased chance of miscarriage.  

Does taking natalizumab increase the chance of birth defects?  

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. We look at research studies to try to understand if an exposure, like natalizumab, might increase the chance of birth defects in a pregnancy. Data on the use of natalizumab in pregnancy is limited. Most available information does not suggest an increased chance of birth defects.  

Natalizumab, like other monoclonal antibodies, crosses the placenta at the end of the first 3 months of pregnancy. This limits the overall exposure to the fetus. The transfer of natalizumab increases for the rest of the pregnancy.  

Does taking natalizumab in pregnancy increase the chance of other pregnancy-related problems? 

Some studies found that natalizumab exposure during pregnancy, especially in the third trimester, was associated with lower infant birth weight and shorter length at birth. Most studies did not find an increased chance of preterm birth (before 37 weeks), stillbirth, placental complications, or poor newborn outcomes compared with unexposed pregnancies, other MS treatments, or the general population. Higher rates of C-section were reported in women using natalizumab or similar medications during pregnancy. 

Studies have reported mild blood disorders in infants exposed to natalizumab during the third trimester, including thrombocytopenia (low number of platelets, which help the blood clot) and anemia (low amount of red blood cells). These conditions did not require treatment and went away on their own within 4 months. One case of neonatal pancytopenia, where all major blood cell types are low, was also reported after exposure to natalizumab throughout pregnancy; it resolved without treatment. Not all babies exposed to natalizumab will have these issues. It is important that your healthcare providers know you are taking natalizumab so your baby can be monitored for these conditions after delivery, if needed. 

Does taking natalizumab in pregnancy affect future behavior or learning for the child?   

Studies on natalizumab use during pregnancy and possible effects on learning and behavior are limited. Available studies found no increased chance of autism, developmental delays, learning problems, behavioral, or psychiatric issues in children exposed during pregnancy. In most pregnancies, children showed normal motor and language development up to 7 years of age. Although one child was diagnosed with autism spectrum disorder and some children had mild behavioral or sleep problems, these were not linked to natalizumab exposure during pregnancy. 

Breastfeeding while taking natalizumab: 

Limited information suggests small amounts of natalizumab pass into breast milk in some women, mainly in the first week after a dose. It has not been detected in the blood of breastfed infants. Because natalizumab is a large protein, it is unlikely to be absorbed in large amounts by the baby when swallowed. Most experts consider breastfeeding while on natalizumab acceptable. Waiting about 2 weeks after delivery before restarting treatment may further lower infant exposure. Be sure to talk to your healthcare provider about all your breastfeeding questions.  

If a man takes natalizumab, could it affect his fertility or increase the chance of birth defects? 

One small study compared 16 men who had severe MS and were taking natalizumab for treatment to 16 other men who were not taking natalizumab. Over 12 months, no difference in fertility (ability to make healthy sperm) was reported between the two groups. For some men, the underlying condition being treated can increase the chance of sexual dysfunction or lower quality of sperm, which can affect fertility. In general, exposures that men have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.  

Please click here for references. 

This sheet is about exposure to losartan in pregnancy and while breastfeeding. This information is based on available published studies. It should not take the place of medical care and advice from your healthcare provider.

What is losartan?

Losartan is part of a group of medications called angiotensin II receptor antagonists (also known as angiotensin receptor blockers (ARBs)). Losartan has been used to treat high blood pressure, protect the kidneys in people with diabetes, and lower the chance of cerebrovascular accident (when the supply of blood to the brain is reduced or blocked). A brand name for losartan is Cozaar®. Losartan is also available in combination with a diuretic called hydrochlorothiazide under the brand name Hyzaar®.

It is usually recommended that women who are pregnant stop taking losartan under their healthcare provider’s guidance. However, it is important to talk with your healthcare providers before making any changes to how you take this medication. Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy.

I am taking Losartan, but I would like to stop taking it before getting pregnant. How long does the drug stay in my body?

The time it takes the body to metabolize (to process) medication is not the same for everyone. In healthy non-pregnant adults, it takes up to 2 days, on average, for most of the Losartan to be gone from the body.

I take losartan. Can it make it harder for me to get pregnant?

It is not known if losartan can make it harder to get pregnant. One animal study did not find effects on fertility (ability to get pregnant).

Does taking losartan increase the chance for miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. It is not known if losartan increases the chance for miscarriage.

Does taking losartan increase the chance of birth defects?

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. We look at research studies to try to understand if an exposure, like Losartanm might increase the chance of birth defects in a pregnancy.

Losartan has not been well studied for use during pregnancy. It is not known if losartan can increase the chance of birth defects when used in the first trimester of pregnancy. There are case reports with typical outcomes after first trimester exposure to losartan when the medication was not used throughout pregnancy. One small study looked at 20 pregnancies exposed to the class of ARB medications. The study reported that 1 infant had craniosynostosis (when the bones in the skull join together too early) and another had inguinal hernia (when soft tissue bulges through a weak place in the belly muscles). Some of the women in this study had diabetes, which has also been linked to an increased chance of birth defects. It is not known if the medication taken, or other factors caused the reported birth defects.

Using losartan in the 2^nd and 3^rd trimesters can increase the chance of other pregnancy complications, such as low amniotic fluid (the fluid that surrounds the baby). Low amniotic fluid levels can cause birth defects. This is discussed in more detail below.

Does taking losartan in pregnancy increase the chance of other pregnancy-related problems?

Losartan use in the 2^nd and/or 3^rd trimester of pregnancy can cause other pregnancy-related problems, such as low levels of amniotic fluid (called oligohydramnios). Low levels of amniotic fluid can lead to poor lung and skull development, joint contractures (joints become stiff and unable to move), and growth restriction in the fetus. Oligohydramnios can also increase the need for an early delivery through induction of labor or C-section. In some cases, oligohydramnios could cause fetal demise.

Low blood pressure, kidney disease, and kidney failure have also been reported in babies exposed to losartan during pregnancy. In some cases, the affected infant died from these complications.

Because of these possible complications, it is usually recommended that women who are pregnant stop taking losartan under their healthcare provider’s guidance. It is important to talk with your healthcare provider before you stop taking losartan. They can talk with you about the best way to treat your condition during pregnancy. Some untreated conditions can also increase risks to a pregnancy.

Does taking losartan in pregnancy affect future behavior or learning for the child?

Studies have not been done to see if losartan can cause behavior or learning issues for the child.

What screenings or tests are available to see if my pregnancy has birth defects or other issues?

Prenatal ultrasounds can be used to screen for some birth defects. Ultrasound can also be used to track the growth of the pregnancy. Talk with your healthcare provider about any prenatal screenings or testing that are available to you. There are no tests available during pregnancy that can tell how much effect here could be on future behavior or learning.

Breastfeeding while taking losartan:

Losartan has not been studied in humans for use during breastfeeding. Information from animal studies suggest that losartan passes into milk and could affect the kidneys of the nursing baby. The product label for losartan recommends women who are breastfeeding not use this medication. But the benefit of using losartan may outweigh possible risks. Your healthcare providers can talk with you about using losartan and what treatment is best for you. Be sure to talk to your healthcare provider about all your breastfeeding questions.

If a man takes losartan, could it affect fertility or increase the chance of birth defects?

Studies have not been done to see if losartan could affect a man’s fertility (ability to get a woman pregnant) or increase the chance of birth defects. In general, exposures that men have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

Please click here for references.

This sheet is about exposure to cigarette smoke in pregnancy and while breastfeeding. This information is based on published research studies. It should not take the place of medical care and advice from your healthcare provider. 

What is in cigarette smoke?  

Cigarette smoke is made of gases and tiny particles that are released when cigarettes are burned. It has over 4,000 chemicals including nicotine, arsenic, lead, and carbon monoxide. When you breathe cigarette smoke into your lungs, the gases and particles get into your blood and organs. Some of these chemicals can cross the placenta and lower the amount of oxygen and food available to the fetus. You can be exposed to cigarette smoke or some of the particles by smoking a cigarette and through secondhand smoke. Secondhand smoke is breathing in the cigarette smoke of another person that is smoking near you.  

It is recommended not to smoke cigarettes at all during pregnancy. If you are smoking, it is best to completely stop smoking as early in pregnancy as possible. Even a few cigarettes a day can lower the amount of oxygen and nutrients the fetus gets. If you cannot stop smoking, lowering the number of cigarettes a day that you smoke could help.  

Quitting is more successful with professional and family/friend support. For free advice and referrals, call the Smoker’s Quitline at 1- 800-QUIT-NOW (1-800-784-8669) from anywhere in the U.S. There are also online resources to help you quit smoking such as https://www.cdc.gov/tobacco/campaign/tips/quit-smoking/index.html. You can also go over your options for quitting with your healthcare provider.   

Can cigarette smoke make it harder for me to get pregnant?  

Some studies have found that exposure to cigarette smoke can make it harder to get pregnant compared to women who are not exposed to cigarette smoke. Women who smoke more than 10 cigarettes a day might have a higher chance of problems with getting pregnant (infertility). A woman’s ability to get pregnant might improve once they stop smoking. Cigarette smoke can also increase the chance of an ectopic pregnancy (when a fertilized egg implants and grows outside the uterus).  

Does cigarette smoke increase the chance of miscarriage?  

Miscarriage is common and can occur in any pregnancy for many different reasons. The chance of miscarriage is higher for women who are exposed to cigarette smoke.  

Does cigarette smoke increase the chance of birth defects?  

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. We look at research studies to try to understand if an exposure, like cigarette smoke, can increase the chance of birth defects. 

Some studies suggest that exposure to cigarette smoke during pregnancy can increase the chance of certain birth defects, including cleft lip and/or palate (an opening in the upper lip or the roof of the mouth), heart defects, and problems with the respiratory system and digestive system. Some studies showed that the chances of having a baby with a birth defect increased with exposure to higher amounts of cigarette smoke. 

Does cigarette smoke increase the chance of other pregnancy-related problems? 

Cigarette smoke is linked with a higher chance of preterm delivery (birth before week 37) and low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth). The more exposure to cigarette smoke that a woman has during pregnancy, the greater the chance for preterm delivery. A baby born preterm has a higher chance for health problems and might need to stay in the hospital longer. Low birth weight can also make it harder for the baby to recover from serious health problems.  

Cigarette smoke is linked to serious problems with the placenta (the organ that grows in the uterus during pregnancy). The placenta delivers nutrients and oxygen to the fetus. Placental problems can include placenta previa (placenta blocks the birth canal) and placental abruption (placenta breaks away from the uterine wall early). These conditions can cause vaginal bleeding and can be life threatening to the pregnant woman and/or result in loss of the pregnancy. Cigarette smoke has also been associated with an increased chance of stillbirth and sudden infant death syndrome (SIDS). 

If I smoke cigarettes near the end of my pregnancy, will it cause withdrawal symptoms in my baby after birth?  

Smoking cigarettes near the end of pregnancy can cause temporary symptoms in newborns soon after birth. These symptoms are sometimes referred to as withdrawal. Symptoms such as irritability, increased muscle tone (stiff muscles) and muscle tremors have been seen in newborns exposed to cigarette smoking during the last weeks of pregnancy. These symptoms are usually short-term and can be treated, if needed. Not all babies exposed to cigarette smoke will have these symptoms. It is important that your healthcare providers know your history of exposure to cigarette smoke so that if symptoms occur your baby can get the care that is best for them. 

Can exposure to cigarette smoke during pregnancy affect future behavior or learning for the child?   

Several studies have found a link between cigarette smoke exposure in pregnancy and learning and behavior problems in the exposed children.  

I am 28 weeks pregnant, and I have been smoking cigarettes throughout my pregnancy. Is it too late to quit?  

It is never too late to quit smoking. If you stop smoking, you stop the exposure to your pregnancy. Stopping at any time during pregnancy can help to improve the growth and development of your pregnancy. Stopping will also help your newborn by not exposing them to secondhand smoke after they are born. Secondhand smoke can affect the health of children after they are born if people smoke around them or in the home. 

Breastfeeding and cigarette smoke: 

It is recommended not to smoke cigarettes while breastfeeding and to avoid exposure to secondhand smoke. Nicotine and other chemicals can pass into breast milk. However, the benefits of breastfeeding might outweigh the risks of cigarette smoking. If you cannot stop smoking completely, lower the amount you smoke as much as possible, and do not smoke in the house or when you are near the baby. Ask others not to smoke around you or in your home.  

For free advice and referrals for quitting, call the Smoker’s Quitline at 1- 800-QUIT-NOW (1-800-784-8669) or visit: https://www.cdc.gov/tobacco/campaign/tips/quit-smoking/index.html. Be sure to talk to your healthcare provider about all your breastfeeding questions.  

If a man smokes cigarettes, could it affect his fertility or increase the chance of birth defects? 

Exposure to cigarette smoke might affect a man’s ability to have sex (erectile function). It can also change the amount of sperm made (sperm counts), as well as the shape and movement of sperm. This might affect a man’s fertility (ability to get a woman pregnant). Some studies have shown that paternal smoking is associated with miscarriage, birth defects such as cleft lip and palate and heart defects, respiratory problems in offspring, and childhood cancers. It is recommended to stop smoking or not smoke around a woman who is pregnant (including in their house or car) because exposure to secondhand smoke can increase the chance of pregnancy complications. For more information on paternal exposures, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/ 

Please click here for references.

This sheet is about exposure to naloxone in pregnancy and while breastfeeding. This information is based on available published literature. It should not take the place of medical care and advice from your healthcare provider.

What is naloxone?

Naloxone is a medication that has been used to block the effects of opioids. Examples of some opioids are heroin, morphine, codeine, oxycodone, and hydrocodone. Naloxone has also been used to stop someone from dying from an opioid overdose. Brand names for naloxone are Narcan® (nasal spray) and Evzio® (auto-injector).

The combination of naloxone and buprenorphine is sold under the brand name Suboxone®. This combination drug is used to treat opioid use disorder (“OUD”). Much of the information on naloxone in pregnancy comes from studies on the use of naloxone and buprenorphine together used rather than the study of naloxone on its own.

Sometimes when women find out they are pregnant, they think about changing how they take their medication, or stopping their medication altogether. However, it is important to talk with your healthcare providers before making any changes to how you take your medication. Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy.

If you have been taking naloxone regularly or have OUD, talk with your healthcare provider before making changes to how you take your medication. Stopping an opioid medication suddenly (also called “cold turkey”) could cause you to go into withdrawal. It is not known if or how withdrawal might affect a pregnancy. It is suggested that any reduction in naloxone be done slowly, and under the direction of your healthcare provider.

I take naloxone. Can it make it harder for me to get pregnant?

Studies have not been done to see if taking naloxone can make it harder for to get pregnant.

Does taking naloxone increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. It is not known if naloxone can increase the chance of miscarriage.

Does taking naloxone increase the chance of birth defects?

Birth defects can happen in any pregnancy for different reasons. Out of all babies born each year, about 3 out of 100 (3%) will have a birth defect. Studies have not shown an increased chance of birth defects when taking naloxone. No studies have been done to see if treatment with naloxone for an opioid overdose in the first trimester can increase the chance of birth defects.

Some studies that have looked at opioids as a group suggest that opioids in general might be associated with an increased chance of birth defects. However, studies have not found a specific pattern of birth defects caused by opioids. Based on these studies, if there is an increased chance of birth defects with opioid use in pregnancy, it is likely to be small.

Does taking naloxone in pregnancy increase the chance of other pregnancy-related problems?

It is not known if taking naloxone can increase the chance of pregnancy-related problems. One study has shown that use of naloxone might increase the chance for pregnancy-related problems such as preterm delivery (birth before week 37) or low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth). No studies have been done to see if treatment with naloxone for an opioid overdose can increase the chance of pregnancy-related problems.

Studies find that women who are pregnant and take opioids in higher doses or for longer than recommended by their healthcare providers (i.e. misuse or “abuse” opioids) have an increased chance for pregnancy problems. These include poor growth of the baby, stillbirth, preterm delivery, and the need for C-section.

Will my baby have withdrawal (Neonatal Abstinence Syndrome) if I continue to take naloxone?

Taking naloxone in pregnancy can increase the chance of Neonatal Abstinence Syndrome (NAS) in the infant after birth. NAS is the term used to describe withdrawal symptoms in newborns from opioid medication(s) that a woman takes during pregnancy. NAS symptoms can include irritability, crying, sneezing, stuffy nose, poor sleep, extreme drowsiness (very tired), yawning, poor feeding, sweating, tremors, seizures, vomiting, and diarrhea. Most often, symptoms of NAS appear 2 days after birth and may last more than 2 weeks.

The chance that NAS will occur depends on the length of time and/or the dose of opioid taken during pregnancy, if other medications were also taken, if baby was born preterm, and/or size of the baby at birth. The chance of NAS is lower with naloxone then with other medications like methadone which are also used to treat OUD. If opioid medications were taken in pregnancy, it is important to let your baby’s healthcare providers know so that they can check for symptoms of NAS and provide the best care for your newborn.

Does taking naloxone in pregnancy affect future behavior or learning for the child?

Studies have not been done to see if naloxone can increase the chance of behavior or learning issues for the child. Some studies on opioids as a general group have found more problems with learning and behavior in children exposed to opioids for a long period of time during pregnancy. However, it is hard to know if this is due to the medication exposure or other factors that might increase the chances of these problems.

Breastfeeding while taking naloxone:

Naloxone gets into breastmilk in small amounts. The amount of medication that does make it into the stomach of the nursing infant is not well absorbed by the body. If naloxone is used to treat opioid overdose, it may be suggested to stop breastfeeding until the opiate is out of the body of the woman who is breastfeeding. Contact the baby’s healthcare provider immediately if your baby has any problems such as increased sleepiness (more than usual), trouble feeding, trouble breathing, or limpness. Be sure to talk to your healthcare provider about all your breastfeeding questions.

If a man takes naloxone, could it affect fertility or increase the chance of birth defects?

Studies have not been done to see if naloxone could affect a man’s fertility (ability to get a woman pregnant) or increase the chance of birth defects. In general, exposures that men have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

Please click here for references.