What you need to know about Rubella (IgM and IgG) tests in pregnant women

This is an automatically translated article.

Rubella is a virus that is common during pregnancy. This is a contagious disease that is very contagious but can be prevented with a vaccine. Rubella test is a necessary job that pregnant women need to do to ensure the health of both mother and baby.

1. What is Rubella?

Rubella is a benign typhus disease. The infection is not dangerous, but it is serious because it can cause birth defects in the unborn baby. Rubella can be passed from mother to baby through blood. For pregnant women, this disease is dangerous, threatening the developing fetus.
If a pregnant woman is infected with Rubella virus during the first 3 months of pregnancy, up to 90% of cases the mother can transmit the virus to the fetus. The virus can cause fetal death or congenital rubella syndrome. Therefore, the definitive diagnosis of Rubella in pregnant women, especially in the first months of pregnancy, is extremely important.

2. What is Rubella IgG and Rubella IgM?

The diagnosis of Rubella is usually based on the quantitative immunoassay of Rubella IgM and IgG. The rubella test is used to detect antibodies in the blood that are produced by the body's immune system in response to an infection caused by the Rubella virus. IgM and IgG are two types of rubella antibodies.
After exposure to Rubella virus, Rubella IgM antibodies will appear in the blood. About 7-10 days after infection, protein levels rise and peak and last for several weeks and then decline.
When the mother has Rubella virus entering the body, IgG antibodies will appear. The IgG antibody will appear later than IgM, but it will remain in the blood for life, helping the mother's body fight the infection caused by the Rubella virus. IgM antibodies in the blood indicate that an infection may have occurred. A site of recent or past Rubella infection will be indicated if IgG antibodies are present.
Congenital rubella syndrome can cause babies to be born with growth retardation, deafness...so, during pregnancy, women should regularly test for Rubella antibodies to ensure adequate immune response.

3. Rubella test (IgG and IgM) in pregnant women

Rubella testing (IgM and IgG) is done for pregnant women who have never been vaccinated against Rubella and have not had rubella before becoming pregnant. The test should be done between 7 and 10 weeks of pregnancy, which is the best time to do it. It is not recommended to test when the pregnancy is over 16 weeks because it is difficult to interpret the results as well as if there are any problems, it is difficult to solve because the fetus is already large at this time.
If IgM results are negative and IgG is positive, then you have had Rubella infection at least 10 weeks before the test, you have protected IgG antibodies. If the IgG level rises after testing 2 weeks apart, it means you have had a previous rubella infection or been vaccinated. If the level of IgG is low, then the patient may have Rubella. Rubella IgM and IgM test should be done after 1 week, if IgM is positive and IgG is increased, the patient has acute rubella.
If IgM test result is positive, IgG is negative: in this case, the patient is newly infected with rubella virus, only IgM antibodies respond. You should have an IgM and IgG test after 2 weeks. If the results show that IgM is still positive, and IgG begins to appear, then the pregnant woman has definitely been infected with the rubella virus. If IgM is positive and IgG is negative, then the IgM result is nonspecific. If a pregnant woman under 12 weeks of age has a positive IgM index, the possibility of the fetus being infected or uninfected, the risk of mother-to-child transmission at this stage is 80%. Children infected with the virus during this period have a very high risk of congenital rubella syndrome.
If IgM is positive, IgG is positive: this is less common. It is more likely to be false positive because pregnant woman has recently been infected with some virus. Pregnant woman needs to be monitored and tested for IgM and IgG, after 2 to 3 times, if the results are still the same, then the pregnancy will be. Women can rest assured.
If IgM is negative and IgG is negative, it is possible that the pregnant woman has never been infected with Rubella and is at risk of getting Rubella, this time the pregnant woman needs to be regularly monitored to handle if she is infected with rubella. This result may also indicate that the patient is infected with rubella but is in the incubation period and that IgM and IgG antibodies have not been produced. So you should have the test again in about 2-3 weeks.

The risk of mother-to-child rubella transmission during the first trimester of pregnancy is 80%, the risk of congenital rubella syndrome at 11-12 weeks of pregnancy is reduced to 33%. At 13-16 weeks of gestation, this rate drops to 11-24% and after 16 weeks, this rate drops to 0%. Determining the time of rubella infection in pregnant women is very important to diagnose the status of the fetus.
To prevent rubella effectively, it is best for women of reproductive age to get rubella vaccine before planning to become pregnant. Vaccination before pregnancy is the best way to protect the health of mother and fetus. Women who intend to become pregnant should go to vaccination centers and medical facilities with a stable source of vaccines.
Vinmec International General Hospital currently has a full range of vaccines including Rubella vaccine, imported directly from the US, Germany with clear origin and good quality. All vaccines are preserved in a modern cold storage system, with a cold storage line meeting GSP standards to ensure that the vaccine always keeps the best quality. Customers will be examined by specialized doctors, fully screened for physical and health problems, advised on preventive vaccines and injection regimens, how to monitor and care after vaccination before Indications for vaccination according to the latest recommendations of the Ministry of Health & World Health Organization to ensure the best effectiveness and safety for customers.
If there is a need for vaccination at Vinmec, please make an appointment directly at the website to be served.

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