A CMV pregnancy will not usually be defined as a “high risk pregnancy” and the course of the delivery is no different than that of any other delivery, but the team will be updated regarding an infection or suspicion for CMV infection.
It is important to know that in the event of a birth following a CMV pregnancy, there is an organized protocol of tests recommended by experts on the subject, which need to be performed during the stay in the neonatal department.
Under the tab Protocols – Diagnosis, Treatment and Follow-Up you can read about the protocols that were given to us from the different hospitals. It is the responsibility of the mother to verify before the birth that the protocol is relevant.
The importance of performing the test in maximum proximity to the time of the birth stems primarily from the need to start treating the baby if the tests discover findings that can testify that the baby is symptomatic.
In addition, performing the tests during the stay in the neonatal department saves much bureaucracy involved in making appointments, receiving Form 17s and arriving at the hospital several times over the first weeks of the baby’s life.
The tests that confirm whether the baby has congenital CMV:
It is highly important to perform these tests in the first two weeks of the newborn’s life. After this time, it would not be possible, for the most part, to determine with certainty whether the infection was intrauterine or an infection that occurred during or after the birth.
Saliva test – performed in some hospitals and provides a reliable result only if negative, and it indicates that the fetus was not infected. The advantage of this test lies in the simplicity of sample collection.
A positive result, which indicates infection, can also stem from passage through the birth canal and also as a result of breastfeeding, and therefore it is not conclusive.
In case of a positive result in the saliva test, make sure to also perform a urine test.
Urine test – provides a reliable and final answer to the question whether the baby was infected during the pregnancy, and it is received a few days after the collection of the sample. However, unlike the saliva test, the collection of the urine sample from the newborn sometimes involves technical difficulties.
Results of the urine test:
Negative results – means that the baby was not infected with the virus. It seals the business of CMV pregnancy and there is no more cause for concern due to the virus once it is done.
After the birth, the baby is the same as other babies, and his post-natal infection should not have a long-term effect.
Positive result – means that the baby was infected during the pregnancy.
If the urine test is positive, perform several tests after the birth:
Blood tests – blood count and liver functions.
Brain ultrasound – performed by a radiologist specializing in children.
Eye fundus examination – performed by an ophthalmologist in order to exclude findings consistent with a congenital infection.
Bera hearing test (abr) – a hearing test that checks the brain stem’s reaction to sound stimuli. You can read about the test in detail under the Q&A tab.
Answers to postnatal tests and continued follow-up
If all virus targeted scans during the pregnancy were normal, it is expected that the postnatal brain ultrasound and the visual test will have normal results.
There is a risk of hearing problems, which cannot be detected in the imaging tests during the pregnancy.
Normal tests –
If the postnatal tests are normal, the baby will be defined a asymptomatic and is expected to have a normal neurological development.
However, a baby defined postnatally as asymptomatic could develop a hearing problem in the future, and therefore, children infected with CMV through intrauterine infection will remain in follow-up with a pediatric infectious diseases specialist and in hearing follow-up over the first years of their lives.
A number of hospitals continue follow-up with a neurologist and an ophthalmologist as well in the first year.
You can read about the differences in the follow-up protocols of the different hospitals on the page Protocol – Diagnosis Treatment and Follow-Up.
Abnormal tests –
If a hearing impairment is discovered, even if this is an isolated impairment without any other sign of infection, with the recommendation of the infectious disease specialist, the baby will start drug treatment with a drug called Valganciclovir, proven to be very effective in stopping the deterioration in hearing and in certain cases even in improving the hearing that was impaired due to the virus.
In some cases, the brain ultrasound finds a finding called LSV. In the past, experts thought that the finding suggests possible future hearing impairment, and those babies would receive drug treatment in the aim of preventing hearing deterioration. Nowadays, even though LSV is found in a high rate of newborns due to improvement in imaging measures, but their follow-up did not indicate any increase in the prevalence of hearing impairment. Therefore, in most cases, these babies will not receive drug treatment.
Some of the hospitals in Israel treat with Valganciclovir according to the treatment protocol by Prof. David Kimberlin from Birmingham University in Alabama, the global pioneer of CMV drug treatment, that dictates that the drug needs to be received twice a day for six months.
Other hospitals follow the treatment protocol constructed following the multiannual work of Prof. Jacob Amir, who was among the first in the world to extend treatment with the drug to the first year of the baby’s life, at a dosage of twice a day for the first three months and once a day for an additional nine months.
You can read about the drug in detail under the Q&A tab.