This sheet is about exposure to phentermine 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 providers. 

What is phentermine?

Phentermine is a medication that has been used as an appetite suppressant to treat obesity. Some brand names for phentermine are Adipex®, Fastin®, Ionamin®, Lomaira™®, or Zantryl®. The combination of phentermine and topiramate is sold under the brand name Qsymia®. MotherToBaby has a fact sheet on topiramate here: https://mothertobaby.org/fact-sheets/topiramate/.  

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 this medication. Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy. 

The product labels for phentermine and the combination of phentermine and topiramate recommend women who are pregnant not use these medications. However, the benefit of using phentermine in a pregnancy may outweigh possible risks. Your healthcare providers can talk with you about using phentermine and what treatment is best for you.  

Obesity can make it harder to get pregnant, and increase the chance of miscarriage, birth defects, or other pregnancy complications. MotherToBaby has a fact sheet on obesity here: https://mothertobaby.org/fact-sheets/obesity-pregnancy/.  

I am taking phentermine, but I would like to stop taking it before becoming 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 8 days, on average, for most of the phentermine to be gone from the body.   

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

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

Does taking phentermine increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. Studies have not been done to see if phentermine can increase the chance of miscarriage. 

Does taking phentermine 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 phentermine, might increase the chance of birth defects in a pregnancy. There is little information on phentermine exposures during early pregnancy. The available data does not suggest an increased chance of birth defects.  

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

Studies have not been done to see if phentermine increases the chance of 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). 

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

Studies have not been done to see if phentermine can increase the chance of behavior or learning issues for the child. 

Breastfeeding while taking phentermine:

Studies have not been done on the use of phentermine while breastfeeding. The product labels for phentermine and the combination of phentermine and topiramate recommend women who are breastfeeding not use these medications. But the benefits of using phentermine might outweigh possible risks. Your healthcare providers can talk with you about using phentermine and what treatment is best for you. Be sure to talk to your healthcare provider about all your breastfeeding questions.  

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

Studies have not been done to see if phentermine could affect male fertility (ability to make healthy sperm) or increase the chance of birth defects. In general, men’s exposures are unlikely to increase the risks to a pregnancy. For more general 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 montelukast 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 montelukast?

Montelukast is medication that has been used to treat asthma and allergies. While montelukast has been used to lower the chance of having an asthma attack, it does not stop an asthma attack. Montelukast is sold under the brand name Singulair®.

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.

Asthma that is not well-treated can increase the chance of complications for the woman who is pregnant as well as the pregnancy. For more information, please see the MotherToBaby fact sheet on asthma at https://mothertobaby.org/fact-sheets/asthma-and-pregnancy/.

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

Studies have not been done in humans to see if montelukast can make it harder to get pregnant. Animal studies showed no effect on fertility (ability to get pregnant).

Does taking montelukast increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. It is not known if montelukast can increase the chance of miscarriage. One study did not show an increase in the rate of miscarriage with use of montelukast during pregnancy.

Does taking montelukast increase the chance of birth defects?

Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. Most available information suggests that the use of montelukast in pregnancy does not increase the chance of birth defects above the background risk. Medical record reviews of thousands of pregnancies reportedly exposed to montelukast did not find an increased chance of birth defects. Other studies looking at a combined total of over 200 pregnancies exposed to montelukast have not suggested an increased chance of birth defects.

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

A few studies have reported a chance for some pregnancy complications when montelukast was used during pregnancy, such as lower birth weight, preterm delivery (delivery before week 37), and preeclampsia (high blood pressure and problems with organs, such as the kidneys), which can lead to seizures (called eclampsia). However, the women in these studies who needed montelukast often had severe asthma and sometimes needed more than one medication. It is not clear if the reported complications are due to montelukast, the condition being treated, or other factors. One study did not report a difference in the birth weight of babies exposed to montelukast when compared to babies exposed to other asthma treatments.

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

Studies have not been done to see if montelukast can increase the chance of behavior or learning issues for the child.

Breastfeeding while taking montelukast:

Montelukast gets into breastmilk in small amounts. One study found that nursing infants would likely receive less of the medication in breastmilk than the dose used to treat an infant directly. Usually, no special precautions are required when using montelukast while breastfeeding. Be sure to talk to your healthcare provider about all your breastfeeding questions.

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

Studies have not been done in humans to see if montelukast could affect a man’s fertility (ability to get a woman pregnant) or increase the chance of birth defects above the background risk. Animal studies showed no effects on fertility. In general, exposures that men have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet on Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.

Please click here for references.

MotherToBaby is currently conducting a study looking at asthma and the medications used to treat asthma in pregnancy. If you are interested in learning more, please call 1-877-311-8972 or visit https://mothertobaby.org/join-study.

This sheet is about exposure to loratadine 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 loratadine?  

Loratadine is an over-the-counter antihistamine. It has been used to treat symptoms of allergic reactions and colds, such as sneezing, runny nose, watery eyes, itchy throat, and hives. Some brand names for loratadine are Claritin® and Alavert®. In the body, loratadine breaks down into desloratadine. Desloratadine is also sold as a prescription antihistamine under the brand name Clarinex®.  

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. 

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

It is not known if loratadine can make it harder to get pregnant. One animal study did not report problems getting pregnant in females exposed to loratadine.  

Does taking loratadine increase the chance of miscarriage?   

Miscarriage is common and can occur in any pregnancy for many different reasons. A study of 163 loratadine exposures during the first trimester of pregnancy did not show an increased chance of miscarriage. 

Does taking loratadine 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 loratadine, might increase the chance of birth defects in a pregnancy. 

Taking loratadine is not expected to increase the chance of birth defects. One early study raised concern about a possible link between loratadine use in pregnancy and hypospadias (a birth defect where the opening of the penis is shifted toward the underside rather than the tip). However, after later studies did not find the same link, the researchers stated that the cases of hypospadias in their original study were most likely due to chance or other factors instead of exposure to loratadine.  

Other studies of loratadine use during pregnancy have not found an increased chance of any kind of birth defect, including hypospadias. Also, studies have not found that infants with hypospadias were more often exposed to loratadine during pregnancy than infants without hypospadias.  

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

Studies of loratadine use in pregnancy have not reported an increased chance of 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).  

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

Studies have not been done to see if loratadine can increase the chance of behavior or learning issues for the child.  

Breastfeeding while taking loratadine:  

Loratadine passes into breast milk in small amounts. The amount of loratadine in breastmilk is too low to cause problems for most babies. Loratadine is one of the preferred antihistamines for use during breastfeeding because it is less likely to cause drowsiness (sleepiness) than some other antihistamines. If you suspect the baby has any symptoms (such as being too sleepy), contact the child’s healthcare provider.  

Taking loratadine might decrease the amount of milk that is made, especially if it is taken in combination with other medications. Be sure to talk to your healthcare provider about all your breastfeeding questions. 

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

Studies have not been done to see if loratadine could affect male fertility (ability to make healthy sperm) or increase the chance of birth defects. 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 lymphocytic choriomeningitis virus (LCMV) during 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 providers.

What is lymphocytic choriomeningitis virus (LCMV)?

LCMV is a virus that is carried by rodents and can be passed to humans. Wild rodents, pet rodents, and rodents in laboratories can all carry LCMV. The most common carrier is the house mouse. It is estimated that between 1 in 20 (5%) and 1 in 10 (10%) of house mice in the United States carry LCMV. House mice in big cities are more likely to carry LCMV. Other rodents, such as hamsters and guinea pigs, can be infected if they have contact with wild mice.

How do you get LCMV?

Infected rodents shed the virus in their body fluids and feces. LCMV infection can happen when humans come in contact with those infected body fluids through their mouth, broken skin, eyes, nose, or when they are bitten by a rodent. The Centers for Disease Control and Prevention (CDC) estimate between 1 in 20 to 1 in 50 adults (2% – 5%) have had an LCMV infection. Getting LCMV after direct person-to-person contact (person-to-person transmission) has not been reported. However, LCMV can pass from a woman who is pregnant to the developing fetus (vertical transmission).

What are the symptoms of LCMV?

Most healthy people with LCMV have no symptoms or mild symptoms. For others, LCMV causes flu-like symptoms such as fever, muscle aches, fatigue, nausea, and vomiting. These symptoms start 1-2 weeks after being exposed to the virus and can last as long as one week. Rarely, some people develop meningitis (swelling of the spinal cord), encephalitis (swelling in the brain), or both. These symptoms can last up to 3 weeks or longer. Symptoms of LCMV infection can be treated. Cases that affect the spine or brain require hospital care.

How can I lower the chance of getting LCMV?

You can lower the chance of infection by following the tips below and on the CDC website at https://www.cdc.gov/vhf/lcm/prevention/index.html.

• Avoid direct physical contact with wild or pet rodents.
• If possible, have someone else care for pet rodents.
• If you come in contact with a rodent or its urine, droppings, or nesting materials, wash hands very well with soap and water.
• Avoid vacuuming or sweeping rodent urine, droppings, or nesting materials. This can cause the virus to become airborne and increase the chance of breathing in the virus.
• If you have wild rodents in your home, have a professional pest control company remove them.
• People in a laboratory or veterinary setting who work with the virus or handle infected animals can lower their chance of infection by wearing proper protective gear, including gloves, face masks, disposable gowns, and by following the appropriate safety precautions. See our MotherToBaby fact sheet on working as a vet or vet tech: https://mothertobaby.org/fact-sheets/vet-vettech/.

How can I find out if I have LCMV?

A blood test can screen for an LCMV infection. If you have had close contact with rodents, rodent droppings, or nesting material, and/or have a fever or other symptoms of LCMV, contact your healthcare provider.

Does getting LCMV increase the chance of miscarriage?

Miscarriage is common and can occur in any pregnancy for many different reasons. Having an LCMV infection during pregnancy can increase the chance for miscarriage, although the exact chance for a miscarriage is not clear. The chance of miscarriage is higher with LCMV infections in the first trimester than with infections later in pregnancy.

Does getting LCMV during pregnancy 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 LCMV, might increase the chance of birth defects in a pregnancy.

If a woman gets LCMV during pregnancy, the virus can pass to the developing fetus. This is called congenital LCMV. The most common birth defect from congenital LCMV are problems with the brain, like fluid in the brain (hydrocephalus/ventriculomegaly), small head size (microcephaly), differences with amount of brain tissue (cerebellar hypoplasia), differences in the pattern of how the brain tissue develops (cortical malformations), and/or damage to existing brain tissue (calcifications). Eye problems that can lead to vision loss (chorioretinitis) are also common. Rarely, LCMV can cause a buildup of fluid in the fetal body (hydrops).

It is not known how likely it is that an LCMV infection in pregnancy will pass to the fetus, or what the chance of birth defects is if the infection does reach the fetus. This is because many cases of LCMV go undetected (since the symptoms in adults are like the flu), and healthy people are not routinely tested for LCMV. The chance of brain and eye problems appears to be higher when a woman who is pregnant gets an LCMV infection in the second or third trimester of pregnancy.

Having a LCMV infection in the past that has gone away does not increase the chance for congenital LCMV in a current or future pregnancy.

Does getting LCMV increase the chance of other pregnancy-related problems?

Congenital LCMV might increase the chance for pregnancy-related problems including preterm delivery (birth before week 37) or low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth).

Does getting LCMV in pregnancy affect future behavior or learning for the child?

Congenital LCMV can affect brain development. Children whose brains are less affected may have mild learning disabilities and motor disabilities (walking later than expected and/or difficulties with walking). Children whose brains are more severely affected may have intellectual disability and severe motor disabilities (unable to walk). Congenital LCMV also increases the chance for a child to have seizures. Vision loss due to chorioretinitis can occur, which may affect how a child learns in school. The chance of developmental problems appears to be higher when a woman who is pregnant gets an LCMV infection in the second or third trimester of pregnancy.

Can I find out if my pregnancy has been affected by LCMV?

Talk to your healthcare providers to learn what screening or testing options are best for you and your pregnancy. Fetal imaging using ultrasound or MRI might detect some of the possible effects of congenital LCMV, such as extra fluid in the brain or around the body. If LCMV infection is suspected in a fetus, the fluid in the uterus around the fetus (amniotic fluid) can be tested. This requires a procedure called amniocentesis to remove a small amount of this fluid. Most babies are diagnosed with congenital LCMV after birth.

Breastfeeding while I have LCMV:

There is no evidence to suggest that LCMV can be passed to a baby through breast milk. Tell your healthcare provider and your baby’s healthcare provider about your infection, rid the home of wild rodents if they are present, and wash your hands well with soap and water before holding your baby. If you suspect your baby has symptoms of LCMV, contact your child’s healthcare provider. Be sure to talk to your healthcare provider about all your breastfeeding questions.

If a man has LCMV, could it affect fertility (ability to get a woman pregnant) or increase the chance of birth defects?

Studies have not been done to see if LCMV could affect male fertility or increase the chance of birth defects above the background risk. Person-to-person transmission has not been reported. 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 lurasidone 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 providers. 

What is lurasidone? 

Lurasidone is a medication that has been used to treat schizophrenia and bipolar disorder. It belongs to a class of medications known as atypical antipsychotics. Lurasidone is sold under the brand name Latuda®. 

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. 

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

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

Does taking lurasidone increase the chance of miscarriage? 

Miscarriage is common and can occur in any pregnancy for many different reasons. Studies have not been done to see if taking lurasidone can increase the chance of miscarriage.  

Does taking lurasidone 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 lurasidone can increase the chance of birth defects because information on the use of lurasidone in pregnancy is limited. Two reports on around 150 pregnancies with exposure to lurasidone did not report an increased chance of birth defects. 

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

Studies have not been done to see if lurasidone can increase the chance of 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). 

I need to take lurasidone during my pregnancy. Will it cause withdrawal symptoms in my baby after birth?  

The use of antipsychotic medications like lurasidone during the third trimester of pregnancy can cause temporary symptoms in newborns soon after birth. These symptoms are sometimes referred to as withdrawal and can include uncontrolled muscle movements, changes in muscle tone, being too sleepy, trouble breathing, and/or trouble with feeding.  

Not all babies who are exposed to antipsychotic medications during pregnancy will have these symptoms. Also, these symptoms have not been reported with use of lurasidone during pregnancy. However, it is important that your healthcare providers know you are taking lurasidone so that if symptoms occur, your baby can get the care that is best for them. 

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

Studies have not been done to see if lurasidone can increase the chance of behavior or learning issues for the child. 

Breastfeeding while taking lurasidone: 

Lurasidone has not been well-studied for use while breastfeeding.  

Very little of this medication is expected to get into breast milk. Among reports of women who breastfed while taking lurasidone, no side effects were reported in the nursing child. Your healthcare providers can talk with you about using lurasidone and what treatment is best for you. Be sure to talk to your healthcare provider about all your breastfeeding questions. 

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

Studies have not been done in humans to see if lurasidone could affect male fertility (ability to make healthy sperm) or increase the chance of birth defects above the background risk. 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.