In every pregnancy, a woman starts out with a 3-5% chance of having a baby with a birth defect. This is called her background risk. This sheet talks about whether exposure to venlafaxine might increase the risk for birth defects over that background risk. This information should not take the place of medical care and advice from your health care provider.

What is venlafaxine?

Venlafaxine is a medication used to treat depression and anxiety in adults. Venlafaxine belongs to a group of antidepressants known as serotonin-norepinephrine reuptake inhibitors (SNRIs). Venlafaxine is marketed under the brand name Effexor®.

I am taking venlafaxine, but would like to stop using it before becoming pregnant. How long does venlafaxine stay in my body?

Individuals break down medicines at different rates. On average, it is thought to take around two days for most of venlafaxine to be gone from the body.

You should always speak with your health care provider before making any changes in your medication. Women who suddenly stop taking their antidepressants are at risk symptoms such as dizziness, stomach upset, and nervousness or anxiety. If a woman plans to stop taking her venlafaxine, it is recommended that this be done slowly over time.

Can taking venlafaxine during my pregnancy increase the chance for miscarriage?

One study found that women taking venlafaxine were more likely to miscarry, but other studies have not found venlafaxine to increase the chance for miscarriage. Depression itself may increase the chance for miscarriage, which makes it difficult to find out whether the medications used to treat depression can also cause miscarriage.

Can taking venlafaxine during my pregnancy cause birth defects in my baby?

Studies have looked at nearly 700 babies born to women who took venlafaxine during early pregnancy or throughout the first trimester. These studies suggest that using venlafaxine during pregnancy is unlikely to increase the chance of birth defects above the 3-5% background population risk.

Does taking venlafaxine during my pregnancy increase my risk of premature birth?

One study found that women taking venlafaxine were more likely to deliver prematurely, but other studies have not found venlafaxine to increase the chance for prematurity. Depression itself may increase the chance for preterm birth, which makes it difficult to find out whether the medications used to treat depression can also cause prematurity.

I need to take venlafaxine throughout my entire pregnancy. Will it cause withdrawal symptoms in my baby?

Possibly. If you are taking venlafaxine at the time of delivery, your baby may have jitteriness, increased muscle tone, irritability, changes in sleep patterns, tremors, difficulty eating and some problems with breathing. Most of the time these effects are mild and go away on their own. However, some babies may need to stay in a special care nursery for several days until their symptoms go away. Not all babies exposed to venlafaxine will have these symptoms.

Should I stop taking venlafaxine during the pregnancy or wean off it before the third trimester?

It is important to talk about the risks and benefits of taking venlafaxine during pregnancy with your health care providers. Studies have shown that when depression is left untreated during pregnancy, there may be increased risks for miscarriage, preeclampsia (dangerous rise in maternal blood pressure), preterm delivery, low birth weight, postpartum mood disorders and other harmful effects (see the MotherToBaby fact sheet on Depression and Pregnancy at http://mothertobaby.org/fact-sheets/depression-pregnancy/). For some women the effects of stopping venlafaxine may be more harmful than the possible risks to the baby of staying on venlafaxine.

If you’re thinking about stopping your use of venlafaxine before or during pregnancy, you should wean off slowly over time with the help of your health care provider. Suddenly stopping venlafaxine can cause headache, nausea, dizziness, insomnia, anxiety, and lack of energy.

Will taking venlafaxine during my pregnancy have any long-term effect on my baby’s behavior and development?

Right now there is no evidence that taking venlafaxine during pregnancy causes changes in the baby’s behavior or intellect. Several studies found no difference in IQ scores between children whose mothers took venlafaxine when compared to mothers taking other antidepressants or who had maternal depression. No meaningful difference in children’s IQ was seen in mothers who took venlafaxine when compared to mothers without depression. More long-term studies are needed to determine if venlafaxine has any effects on a child’s learning or behavior.

Can I take venlafaxine while breastfeeding?

Venlafaxine and its breakdown products are found in breast milk. The majority of reports on taking venlafaxine while breastfeeding have not described harmful effects in the infants. Long term studies on children older than two years have not been done. Because the amount of medicine in the breast milk can vary, infants can be watched for unusual sleepiness and monitored for good weight gain. If there is a concern, infant blood levels can be taken. Be sure to talk to your health care provider about all your choices for breastfeeding.

What if the father of the baby takes venlafaxine?

There are no studies looking at possible risks to a pregnancy when the father takes venlafaxine. In general, exposures that fathers have are unlikely to increase risks to a pregnancy. For more information, please see the MotherToBaby fact sheet on Paternal Exposures and Pregnancy at http://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/pdf/.

References Available By Request