PLEGnancy, the PLEGRIDY® (peginterferon beta-1a) Pregnancy Exposure Registry

If you become pregnant while taking PLEGRIDY or were taking PLEGRIDY any time since 14 days prior to the first day of your last menstrual period before conceiving, it is important for you to know about this pregnancy registry and how you can participate.

You may have asked yourself whether your relapsing multiple sclerosis (MS) and the medication you take will affect your baby

The effects of a particular medicine on the health of a baby are often unknown because pregnant women are not usually included in studies where a potential new medicine is being tested. Pregnancy registries aim to collect information that could help women in the future and their doctors make more informed decisions about using a particular medicine during pregnancy. Click here to learn more about relapsing MS and pregnancy.

Learn how you can help. This is a registry for women with MS who are pregnant and have taken PLEGRIDY. Information about health during pregnancy will be collected from participants and their doctors; information on the health of their babies will also be collected from the baby’s doctor. In the future, other pregnant women who are exposed to PLEGRIDY may have more information as a result of this registry about how their pregnancies and babies may or may not be affected. Find out how to take part.


PLEGRIDY® (peginterferon beta-1a) is a prescription medicine used to treat people with relapsing forms of multiple sclerosis (MS).

Important Safety Information

Before beginning treatment, you should discuss with your healthcare provider the potential benefits and risks associated with PLEGRIDY.

PLEGRIDY can cause serious side effects. Call your healthcare provider right away if you have any of the symptoms listed below.

  • Liver problems, or worsening of liver problems including liver failure and death. Symptoms may include yellowing of your skin or the white part of your eye, nausea, loss of appetite, tiredness, bleeding more easily than normal, confusion, sleepiness, dark colored urine, and pale stools. During your treatment with PLEGRIDY you will need to see your healthcare provider regularly. You will have regular blood tests to check for these possible side effects.
  • Depression or suicidal thoughts. Symptoms may include new or worsening depression (feeling hopeless or bad about yourself), thoughts of hurting yourself or suicide, irritability (getting upset easily), nervousness, or new or worsening anxiety.

Do not take PLEGRIDY if you are allergic to interferon beta or peginterferon beta-1a, or any of the other ingredients in PLEGRIDY.

Before taking PLEGRIDY, tell your healthcare provider if you:

  • Are being treated for a mental illness or had treatment in the past for any mental illness, including depression and suicidal behavior
  • Have or had liver problems, low blood cell counts, bleeding problems, heart problems, seizures (epilepsy), thyroid problems, or any kind of autoimmune disease
  • Take prescription and over-the-counter medicines, vitamins, and herbal supplements
  • Are pregnant or plan to become pregnant. It is not known if PLEGRIDY will harm your unborn baby. Tell your healthcare provider if you become pregnant during your treatment with PLEGRIDY
  • Are breastfeeding or plan to breastfeed. It is not known if PLEGRIDY passes into your breast milk. Talk to your healthcare provider about the best way to feed your baby if you use PLEGRIDY.

PLEGRIDY can cause additional serious side effects including:

  • Serious allergic reactions. Serious allergic reactions can happen quickly. Symptoms may include itching, swelling of the face, eyes, lips, tongue, or throat, trouble breathing, feeling faint, anxiousness, skin rash, hives, or skin bumps
  • Injection site reactions. PLEGRIDY may commonly cause redness, pain or swelling at the place where the injection was given. Call your healthcare provider right away if an injection site becomes swollen and painful or the area looks infected and it does not heal within a few days. You may have a skin infection or an area of severe skin damage (necrosis) requiring treatment by a healthcare provider
  • Heart problems, including congestive heart failure. While PLEGRIDY is not known to have any direct effects on the heart, some people who did not have a history of heart problems developed heart muscle problems or congestive heart failure after taking interferon beta. If you already have heart failure, PLEGRIDY may cause your heart failure to get worse. Call your healthcare provider right away if you have worsening symptoms of heart failure such as shortness of breath or swelling of your lower legs or feet while using PLEGRIDY
    • Some people using PLEGRIDY may have other heart problems, including low blood pressure, fast or abnormal heart beat, chest pain, heart attack, or a heart muscle problem (cardiomyopathy)
  • Autoimmune diseases. Problems with easy bleeding or bruising (idiopathic thrombocytopenia), thyroid gland problems (hyperthyroidism and hypothyroidism), and autoimmune hepatitis have happened in some people who use interferon beta
  • Blood problems and changes in your blood tests. PLEGRIDY can decrease your white blood cells or platelets, which can cause an increased risk of infection, bleeding or anemia, and can cause changes in your liver function tests. Your healthcare provider should do blood tests while you use PLEGRIDY to check for side effects
  • Seizures. Some people have had seizures while taking PLEGRIDY, including people who have never had seizures before.

The most common side effects of PLEGRIDY include:

  • Flu-like symptoms. Many people who take PLEGRIDY have flu-like symptoms early in the course of therapy. These symptoms are not really the flu. You cannot pass it on to anyone else. Symptoms may include headache, muscle and joint aches, fever, chills, or tiredness.
    • You may be able to manage these flu-like symptoms by taking over-the-counter pain and fever reducers, and drinking plenty of water. For many people, these symptoms lessen or go away over time.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Please see full Prescribing InformationMedication Guide, and Instructions for Use for additional important safety information. This information is not intended to replace discussions with your healthcare provider.