After suffering a prior miscarriage, Anthea Marsh was thrilled to be attending her eight-week appointment with her obstetrician after falling pregnant again.
But minutes into the appointment, she said her obstetrician had asked her husband why he was looking unwell.
"I said, 'Oh, he's been sick with CMV (Cytomegalovirus)'. And I just saw her face drop," she said.
Anthea was immediately tested to see if she had also contracted the virus and also tested positive, despite being asymptomatic.
"We had conceived when he [Anthea's husband] had the virus, so we were told our chances were very small of having a healthy baby," she said.
The couple made the heart-wrenching decision to terminate the pregnancy.
She said what was so difficult to comprehend was why she was never warned about it before, during previous pregnancies, or by their GP when they had found out her husband had been sick with the virus.
"Even then, there was no talk of it being an issue for me," she said.
So what is CMV and why is this "common virus" so dangerous for unborn babies?
CMV: The silent virus
The virus can be passed on from person-to-person without their knowledge, usually via close contact.
The most common sources of infection are young children, so if there is already a child in the family, or the mother works with young children, the chances of contracting it are much higher.
It affects around 83 per cent of adults, with most remaining asymptomatic, otherwise it is felt like a cold or flu. Once a person is infected, the virus remains "viable" but usually inactive, or dormant in the body.
Women who catch CMV while pregnant, could pass it onto their unborn child — known as congenital CMV — and it's the most common infectious cause of disability in newborn babies, despite affecting just 0.2-2.2 per cent of births.
While most babies born with CMV will not have the disease, it can sometimes cause injury to the baby's brain, including hearing loss, developmental delay and learning problems.
In serious cases, it can cause stillbirth, infant death or severe disabilities like cerebral palsy or profound hearing loss.
CMV Australia says studies have shown that out of 1,000 live births, about six infants will have congenital CMV infection and one to two of those six infants (about one in 1,000 infants overall) will have permanent disabilities of varying degree.
In Australia, more than 400 babies each year are born with a life-long disability caused by CMV.
So, why are many people, particularly parents-to-be still in the dark?
The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) three years ago released a guide for medical practitioners about CMV.
Its number one recommendation is "all pregnant women and women trying to conceive, should be given information about CMV prevention as part of routine antenatal or pre-pregnancy care".
But according to surveys conducted by RANZCOG, less than 10 per cent of maternity care providers routinely provided education on CMV prevention.
She is one of several mothers who told the ABC they were never told about it prior to conception, or in early pregnancy.
Obstetrician and gynaecologist Dr Kelly van den Haspel said awareness among medical professionals was improving but there was still a way to go.
"The trickiness is the testing for it, and then the outcome for it, it's really quite complex and so I think that's why people aren't that comfortable perhaps discussing it because there's no treatment for it," she said.
"The biggest area that we need to work on is just general education of health providers who provide any obstetric care, including GPs who are providing pre-pregnancy care. I think that sort of education of both doctors and of patients is probably where we sort of need to aim a little bit more time and thought into."
Paediatric infectious disease specialist Dr Julia Clark has worked in the research space for congenital CMV for many years, including a Queensland trial for screening the virus in newborns.
She said there is still a lot of ongoing work and discussion about CMV happening behind the scenes, including international trials for a treatment during pregnancy.
"The interest has shifted a little bit from a paediatric point of view ... so we were obviously very interested in the babies once they were born, to actually trying to do something more interventional during pregnancy and that would mean pregnancy screening and interventions during pregnancy," she said.
But, for now, Dr Clark said it was most important to educate women about the risks.
"Trying to decrease the amount of women who pick up CMV during pregnancy is even better," she said.
How you can prevent it
CMV is generally spread by direct contact through bodily fluids such as saliva, nasal mucous, or urine, for example, through kissing children on the lips, sharing food, handling children's toys or changing nappies without washing hands.
The biggest preventative measure for women looking to conceive, or in early pregnancy, is strict hygiene practices.
- Do not share food, drinks, or utensils used by young children (less than three years of age)
- Do not put a child's dummy in your mouth
- Avoid contact with saliva when kissing a child
- Attention to hand hygiene, when changing nappies, or when in contact with urine or wiping a child's nose
- Clean toys, countertops and other surfaces that come into contact with a child's urine or saliva
- Do not share a toothbrush with a young child
How do you know if you've had it?
The greatest risk of mother to baby transmission occurs in a "primary" infection, if the woman has never had it before.
"Generally, the risk of transmission through the placenta and to your baby is much lower if it's a reactivation of an infection," Dr van den Haspel said.
"So definitely a primary infection in the first half of pregnancy has that biggest risk of transmission through the placenta and to infect your baby."
However, Dr Clark said a reactivation of CMV can be just as dangerous.
"There are different risks at different times during your pregnancy," she said.
"So your primary infection is more of a risk in the first part of your pregnancy and reactivation [is more so in the] second part," she said.
She said, statistically, the amount of women who have had CMV by the time they are of child-bearing age was greater than those who have not.
"So statistically there are more women who may reactivate and potentially could reactivate, so many babies who are born with congenital CMV have had reactivation rather than primary CMV," she said.
"So it's not a distinguisher for being able to not have congenital CMV… people used to think that it was milder, but that's probably not true anymore the more we understand about how and what happens with CMV reactivation.
"But it's difficult to tell to be honest, about that. And the worry is always the primary CMV because that seems to kind of hit hard quickly."
A simple blood test can determine if a person has had CMV, but Dr van den Haspel said it was not something doctors routinely screened, and that is because a past infection does not offer complete protection against congenital CMV.
"There's not enough evidence to sort of say that we should screen everybody in early pregnancy, and then screen everybody later on to make sure you haven't had any change in those immunity levels," she said.
"It's a bit of a tricky illness."
CMV Australia says testing is currently recommended for pregnant women who develop flu-like symptoms or malaise, or when ultrasound reveals a fetal abnormality.
However, pregnant women and women planning a pregnancy can discuss CMV testing with their doctor, particularly if they work in high risk settings (for example, in child care centres) or have very young children at home.
Not an easy decision for parents
If you find out you have contracted the virus during a pregnancy, Dr van den Haspel said you would be referred to a maternal fetal specialist.
"What they would do is monitor baby for any signs of transmission across the placenta," she said.
"So you can have an amniocentesis, where they take a little sample of the fluid from around baby to see if they'd be positive on the PCR for CMV, and then they monitor bub with ultrasound and also with an MRI during the pregnancy.
"There's a few different things that we can see [on an ultrasound]. So sometimes there's some changes in the fluid level around baby."
She said if something of concern was found on the imaging, it is something that can be monitored closely with scans, and some women do choose to terminate the pregnancy based on those findings.
"Sometimes you can have that sample of the fluid and find out that [the baby has] been infected, but that doesn't necessarily mean the baby will become affected by the disease," she said.
"So some ladies will have a positive sample of the amniotic fluid but as they monitor baby during the pregnancy, they don't see any of those abnormal features and those bubs tend to have a pretty good outcome."
There is currently no treatment or proven therapy to prevent or treat a fetal infection.
CMV Australia also says consideration should be given to waiting at least 12 months before becoming pregnant again.
