This sheet is about exposure to prilocaine 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 prilocaine?

Prilocaine is a local anesthetic. Local anesthetics are medications used to numb areas of the body for short periods of time. Prilocaine is given by injection (a shot) during some dental procedures and for surgical procedures on other areas of the body, such as the foot.

Prilocaine is also available in combination with another medication called lidocaine as a topical cream (used on the skin). The brand name for this topical medication is EMLA®. For more information on lidocaine, please see the MotherToBaby fact sheet at: https://mothertobaby.org/fact-sheets/lidocaine/.

Some people have developed methemoglobinemia (a condition where the blood cannot carry enough oxygen) after using prilocaine. While it can happen to anyone, some people might be more at risk than others. Most people recover well with treatment. Talk with your healthcare providers about using prilocaine and any risks specific to you.

I was given prilocaine for a procedure. Can it make it harder for me to get pregnant?

Studies have not been done in humans to see if prilocaine can make it harder to get pregnant. One animal study reported that prilocaine did not affect fertility (ability to get pregnant).

Does prilocaine 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 prilocaine can increase the chance of miscarriage.

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

Studies have not been done in humans to see if prilocaine can increase the chance of birth defects. Information from animal studies does not suggest that prilocaine would significantly increase the chance of birth defects.

Does using prilocaine in pregnancy increase the chance of other pregnancy-related problems?

Studies have not been done to see if prilocaine 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).

There are case reports of methemoglobinemia in the newborns of some people who received high doses of prilocaine during pregnancy.

Does prilocaine affect future behavior or learning for the child? 

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

Breastfeeding while using prilocaine:

Prilocaine has not been well studied for use while breastfeeding. Based on information about similar medications, receiving a single dose of prilocaine during breastfeeding is unlikely to cause side effects in a breastfed infant. If he person who is breastfeeding uses prilocaine topically, it is unlikely to affect the breastfed infant if applied away from the breast. Be sure to talk to your healthcare provider about all your breastfeeding questions.

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

Studies have not been done to see if prilocaine could affect men’s fertility (ability to get a partner pregnant) or increase the chance of birth defects. In general, exposures that fathers or sperm donors 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 to view references.

This sheet is about exposure to guanfacine 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 guanfacine? 

Guanfacine is a medication approved to treat high blood pressure and attention deficit hyperactivity disorder (ADHD). It has also been used for Gilles de la Tourette’s syndrome, opioid withdrawal and sedation weaning (decreasing the amount of sedative medications someone is exposed to) in Intensive Care Units (ICU). Some brand names for guanfacine are Estulic®, Intuniv® and Tenex®.  

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. If you have been taking this medication regularly, you should not stop taking it suddenly. If you do plan to stop this medication, it should be stopped slowly under the care of your healthcare provider. 

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

Studies have not been done to see if guanfacine could make it harder to get pregnant. Animal studies did not find that guanfacine affected fertility (ability to get pregnant). 

Does taking guanfacine 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 guanfacine could increase the chance of miscarriage. 

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

Guanfacine has not been well studied. In a small study of 30 pregnancies, no birth defects were reported after exposure to guanfacine. Animal studies also did not show an increased chance of birth defects. 

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

Studies have not been done to see if guanfacine can increase the chance of other 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). One study looked at the pregnancies of 30 women who were given guanfacine to treat preeclampsia (high blood pressure and problems with organs, such as the kidneys),which can lead to seizures (called eclampsia).. They did not find changes in the fetal heart rate during pregnancy. 

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

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

Breastfeeding while taking guanfacine:  

Guanfacine has not been studied for use in breastfeeding. Talk with your healthcare provider about the best way to treat your medical condition while breastfeeding. Be sure to talk to your healthcare provider about all your breastfeeding questions.  

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

Studies have not been done to see if guanfacine could affect men’s fertility (ability to get a woman pregnant) or increase the chance of birth defects. In general, exposures that fathers or sperm donors 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 atenolol 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 atenolol?

Atenolol is a medication that has been used to treat high blood pressure, chest pain (angina), and heart rhythm issues (arrhythmias). It has also been used to treat, prevent, and improve survival after a heart attack. It belongs to the class of medications called beta-blockers. A brand name for atenolol is Tenormin^®.

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.

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

It is not known if atenolol can make it harder to get pregnant.

Does taking atenolol 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 atenolol increases the chance of miscarriage.

Does taking atenolol 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. Studies have not been done to see if atenolol increases the chance of birth defects. Studies on the use of beta-blockers in general during pregnancy have not reported an increased chance of birth defects.

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

Atenolol has been linked with reduced growth of the fetus (smaller in size and/or low birth weight). It is not clear if this happens because of the medication, the condition being treated, or other factors. One study did find that atenolol can directly affect blood flow through the placenta, which might be linked with poor growth of the fetus, causing low birth weight (weighing less than 5 pounds, 8 ounces [2500 grams] at birth).

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

Studies have not been done to see if atenolol 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 there could be on future behavior or learning.

Breastfeeding while taking atenolol:

Atenolol passes into breastmilk. There have been reports of babies with slow heart rate, low blood pressure, a bluish color in the skin due to a lack of oxygen in the blood (cyanosis), and low body temperature after being exposed to atenolol through breast milk. If you suspect the baby has any symptoms (slow heart rate, low blood pressure, a bluish color in the skin, lips, or fingernails) contact the child’s healthcare provider.

The product label for atenolol recommends women who are breastfeeding not use this medication. But, the benefit of using atenolol may outweigh possible risks. Your healthcare providers can talk with you about using atenolol and what treatment is best for you. Be sure to talk to your healthcare provider about all of your breastfeeding questions.

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

Atenolol may lower the amount of testosterone and cause erectile dysfunction, which could affect a man’s fertility (ability to get a woman pregnant). Also, men with conditions like hypertension may have problems with 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.

This sheet is about exposure to metoprolol 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 metoprolol? 

Metoprolol is a medication that has been used to treat high blood pressure, fast heart rate, and migraines. It is part of a class of medications known as beta-blockers. Some brand names for metoprolol are Lopressor®, Toprol®, Apo-Metoprolol®, Betaloc®, Novo-Metoprolol®, and Minimax®.  

Sometimes when women find out they are pregnant, they think about changing how they take their medication, or stopping their medication all together. However, it is important to talk with your healthcare providers before making any changes to how you take your medication. Having high blood pressure can increase the chance for preterm delivery and low birth weight. In addition, high blood pressure in pregnancy can increase the chance of developing pre-eclampsia (high blood pressure and problems with organs, such as the kidneys) that can lead to seizures (called eclampsia). Your healthcare providers can talk with you about the benefits of treating your condition and the risks of untreated illness during pregnancy. 

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

It is not known if taking metoprolol can make it harder to get pregnant.  

Does taking metoprolol 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 metoprolol can increase the chance of miscarriage. 

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

It is not known if metoprolol increases the chance of birth defects. Animal studies have not reported an increased chance of birth defects. A large study in humans found that beta-blockers in general did not increase the chance of heart defects.  

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

Metoprolol has been associated with intrauterine growth restriction (less growth of the fetus than expected). It is hard to know if a medication, the medical condition being treated, or other factors (such as age, health, other exposures) could be the cause of the growth restriction.  

Metoprolol use in late pregnancy might cause the baby to have symptoms such as slowed heart rate and low blood sugar. Talk with your healthcare providers about your use of metoprolol so that if symptoms occur your baby can get the care that is best for them. 

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

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

Breastfeeding while taking metoprolol: 

Metoprolol passes into breast milk in small amounts. Studies on the use of metoprolol during breastfeeding have not reported side effects in breastfed infants. If you suspect the baby has any symptoms (such as slow heart rate, being too sleepy, having trouble with feeding, or pale skin), contact the child’s healthcare provider. Be sure to talk to your healthcare provider about all your breastfeeding questions. 

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

It is not known if metoprolol could affect male fertility (ability to make healthy sperm) or increase the chance of birth defects. In general, exposures that fathers or sperm donors have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet on Paternal Exposures and Pregnancy at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/. 

Please click here for references.  

What is a MotherToBaby Pregnancy Study? Who is MotherToBaby?

A MotherToBaby Pregnancy Study is a research study that collects information from a woman during her pregnancy along with information about her baby’s health after the pregnancy is over. MotherToBaby Pregnancy Studies are conducted by the non-profit Organization of Teratology Information Specialists (OTIS) and are coordinated by the University of California, San Diego.

Will I be asked to take any additional medications? Or to stop taking a medication?

No. Our studies are strictly observational, which means we will never ask you to take any new medicines, experimental drugs or to change any part of your healthcare routine. If you enroll, you’ll simply be followed by our team through the remainder of your pregnancy, and your baby will be followed for a period of time after birth.

Why are pregnancy studies important?

Pregnant women are typically excluded from clinical trials that occur when a drug is being developed. This means that once a medication is approved by the US Food & Drug Administration (FDA), it starts being prescribed to patients with little to no information on the safety of the drug if used during pregnancy. Yet 9 out of 10 pregnant women in the U.S. take medication. Our studies provide critical information on the safety of medication use by observing pregnant women and their babies. Our findings are used by healthcare providers and may be listed on drug labels that come with prescription medications.

How does a MotherToBaby Pregnancy Study work?

After you let us know that you are interested, the first thing that will happen is that we will contact you to get some information and to see if you are eligible to participate. The 3 groups of women we’re looking for are:

If you’re eligible to join one of these groups, we’ll tell you exactly what is involved in the study so you can decide if you want to participate. All of our studies include:

Depending on the study you join, you may also be eligible for a free in-home examination of your baby by one of our pediatric specialists and/or free neurodevelopmental follow-up until your child is 5 years old.

Visit our website (https://mothertobaby.org/studies/) for a list of our ongoing studies and to watch a video of a past participant describing her experience being in a MotherToBaby study.

Will the information I share with MotherToBaby be kept private?

All the information we request will be kept confidential. Your privacy is important to us. We comply with strict regulations and laws set forth by state and federal agencies as well as the Institutional Review Board (IRB) at the University of California, San Diego, who oversees and monitors our research. Since we ask for your permission to obtain medical records, we will also give you detailed information on how this data will be used and how we will protect your privacy.

What types of questions will you ask me?

We’ll ask you questions about your health history, your pregnancy and the birth of your child. You’ll be asked about exposures to medications, illnesses, pregnancy related tests, previous pregnancies, medical condition symptom control (if participating in group 1 or 2), and questions about demographics. After your baby is born, we may also ask you questions about your breastfeeding practices (should you choose to nurse your baby) as well as questions about your child’s development.

What are the benefits of participating?

Will I find out the results of the study?

Yes! We send all participants and their health care providers the results of the study. This information might prove useful to you in a future pregnancy, or be used by your provider when treating other patients.

What if I agree to participate and later change my mind?

Because your participation is voluntary, you can withdraw from the study at any time.

I have more questions. Who can I contact?

Contact MotherToBaby Pregnancy Studies by:

• Phone (toll-free): 877-311-8972 (Monday-Thursday 7am-7pm Pacific; Friday 7am-6pm Pacific)
• Email: mothertobaby@ucsd.edu
• Visit: https://mothertobaby.org/join-study/