Q. What are the risks of MMR vaccine during pregnancy?

Answered by
Dr. Sanjay Kumar Bhattacharyya
and medically reviewed by iCliniq medical review team.
This is a premium question & answer published on Nov 30, 2016 and last reviewed on: Dec 04, 2020

Hi doctor,

I am in an unplanned pregnancy of 6 weeks. Two to three weeks after conceiving, I unknowingly drank wine when I was highly stressed. I had a fluoride treatment at the dentist and received an MMR booster vaccine. My doctor is concerned about the potential risks. Online sources seem fine or inconclusive. I would really appreciate another opinion. Thank you in advance.



Welcome to

  • The MMR vaccine is a real threat in a pregnant state (mumps, measles and rubella). Yes, nobody could say you either continue or terminate the pregnancy.
  • Just go through the details. If you wish to adopt the potential risk, then you can continue.

For further information consult an obstetrician and gynaecologist online -->

Thank you doctor,

What will be the issue? Will the mother contract rubella? Or are there other potential effects on the development of the fetus? Would scans show any issues?



Welcome back to

Really, there is a danger if the mother develops rubella naturally. In that case, definitely there is a known risk of the fetus developing some anomalies termed as congenital rubella syndrome.

But, the fact is not the same if you have received a vaccination. This vaccine, though contain live rubella virus, but in a much inactivated form.

A few studies have been conducted to know the effect of this vaccine virus over the developing fetus where the mother like you received the vaccine inadvertently. The results of those studies are reassuring.

  • In the first study, 293 women have been followed through who were vaccinated with rubella-containing vaccine within 6 weeks of their last menstrual period. None of the babies had permanent abnormalities compatible with congenital rubella syndrome.
  • In the second study, over 30,000 pregnant women inadvertently received MR vaccine. The vaccine had been given either during pregnancy (the majority were less than 12 weeks pregnant) or up to 30 days before these women had conceived.
  • Extended follow-up of the outcome of these pregnancies was very reassuring. Whilst a very small number of babies were shown to have been exposed to the weakened vaccine virus in the womb, fortunately, no babies developed congenital rubella syndrome.
  • But still, we do not recommend this vaccine in pregnant state to avoid any potential danger. Reports are there that there is no such risk and it is not also straightaway indicated to terminate the pregnancy if MMR has been administered.
  • So now, after this detailed discussion, there always exists individualization as each pregnancy is different and reacts in a different manner.

Yes, there is always a role of USG (ultrasonography) for the purpose of detection of any anomalies.

This needs to be precise and only can detect those anomalies if any, either if the sonologist is experienced enough to conduct an anomaly scan and the defects are quite well developed or large enough to be demonstrable.

For further doubts consult an obstetrician and gynaecologist online -->

Hi doctor,

Thank you so much for taking the time to provide such a detailed response. In regards to none of the babies had permanent abnormalities compatible with congenital rubella syndrome, are there any indications that other abnormalities could form from the MMR vaccine? Either during or after pregnancy? For example, I have been told that the virus could travel to the fetus; would it have any other potential effects? I understand that this is my decision, but appreciate your insight.



Welcome back to

When a mother gets infected with natural rubella, the virus gets transmitted through the placenta and particularly in early pregnancy like 6 to 8 weeks, it affects the fetus.

The damage is more when the pregnancy is early. The abnormalities have a specific type, which is combinedly termed as congenital rubella syndrome.

In this suspicion, we do not advise this vaccine in pregnant state, which contains the live rubella virus suspecting that it will also travel the placenta creating similar problems.

Now, as per the study result, they have found few anomalies. But, those are not related or similar to those due to rubella infection in the mother.

  • You may ask me, why those anomalies? The answer is, as a general, there are 2% cases where anomalies can be found in newborn and those anomalies in newborn have been described here. This is a natural phenomenon to have this.
  • So, the researchers told the vaccine do not have any effect over the pregnancy as these anomalies are found in all general population throughout the world. These anomalies or abnormalities obviously are not related to either MMR or rubella infection.

For further information consult an obstetrician and gynaecologist online -->

Was this answer helpful?


Same symptoms doesn’t mean you have the same problem. Consult a doctor now!

Related Questions:
Is the patient free from Fanconi anemia if reports are negative for chromosomal breakage syndrome?

.. anemia, there is a presence of birth defects along with severed degree anemia. If such a finding is present, then further work out has to be done for that. I have checked your report (attachment removed to protect patient identity). It is not show...   Read full

I am 18 weeks pregnant.I am tensed about low lying placenta.Kindly help.

.. gone through your reports (attachment removed to protect patient identity). This level 2 anomaly scan is absolutely normal for the foetus pertaining to its growth and absence of any congenital anomalies.  The concern regarding the low lying plac...   Read full

I put scotch tape on penis to regenerate foreskin. Will my babies have birth defects?

.. not understand what made you do this practice and what benefit would you expect in this practice? There are no scientific studies available to support using this practice. Let me give my opinion. First of all, the mucous membrane is one of the h...   Read full


Also Read Answers From:

ideaComprehensive Medical Second Opinion.Submit your Case

Also Read

Management of Coronasomnia
Coronasomnia refers to increased sleep problems among people during the COVID-19 pandemic. Read the below article to get...  Read more»
Balantidiasis - Causes, Signs and Symptoms, Diagnosis, Treatment, and Prevention
Balantidiasis is a rare bacterial infection caused by a parasite called Balantidium coli. Read the article below to know...  Read more»
JAK Inhibitors in Treating Rheumatoid Arthritis
Doctors mainly suggest JAK or Janus kinase inhibitors for patients with rheumatoid arthritis to ease their symptoms. Rea...  Read more»

Ask your health query to a doctor online?

Ask an Obstetrician & Gynaecologist Now

* guaranteed answer within 4 hours.

Disclaimer: No content published on this website is intended to be a substitute for professional medical diagnosis, advice or treatment by a trained physician. Seek advice from your physician or other qualified healthcare providers with questions you may have regarding your symptoms and medical condition for a complete medical diagnosis. Do not delay or disregard seeking professional medical advice because of something you have read on this website. Read our Editorial Process to know how we create content for health articles and queries.