Ms Yvonne Khoo
nearly lost her life
when she caught
the COVID-19 virus
in her 25th week of pregnancy.
Unvaccinated, Ms Khoo had
severe respiratory failure when
she was admitted to Singapore
General Hospital (SGH) in late
October last year.
(Photo: Ms Yvonne Khoo)
At SGH’s intensive care unit
(ICU), she immediately had a
breathing tube connected to a
machine to help her breathe.
Even with the ventilator, “her
oxygen level was very, very
low,” said Dr Sewa Duu Wen,
Senior Consultant, Department
of Respiratory and Critical Care
Medicine, SGH. He is also Director,
Ms Khoo’s oxygen level had
plunged to 70 per cent from the
normal 95 to 100 per cent. Oxygen
levels of under 90 per cent are
considered a clinical emergency.
“Her condition was precarious.
Our consideration was how to
save the mother, even as we
also wanted to save the baby,”
Dr Sewa said.
<<Dr Sewa Duu Wen (with Nurse Clinician Anwen Chan Shi)
demonstrates on a mannequin the setting up of the ECMO machine, which takes over the
functions of a patient’s lungs and heart to allow the infected lungs to recover.>>
Meanwhile, a large team
of specialists — respiratory,
intensive care, infectious
diseases, neonatal care — was
quickly assembled, and put
on standby and on high alert.
“Everyone had to come together
literally at the snap of the
finger,” said Dr Tan Wei Ching,
Senior Consultant, Department
of Obstetrics & Gynaecology
One option the team
considered was to deliver the
baby immediately to improve
Ms Khoo’s chances of survival.
For Dr Tan, a key consideration
was the baby’s prematurity.
“Should we deliver baby at just
25 weeks?” she said, noting that
issues like safe transfer of Ms Khoo
to the operating theatre (OT)
with equipment necessary for
a caesarean section and other
emergencies, or delivery at the
ICU, also had to be addressed.
Ms Khoo’s condition was
deteriorating rapidly. Her
COVID-19 infection was
complicated not just by her
pregnancy, but also an underlying
kidney condition. Compared to
other people, pregnant women
have a greater chance of
developing severe complications
if they are infected with the virus.
Treatment for Ms Khoo’s kidney
disease had also weakened her
immune system. She was thus more
prone to a very severe form of
COVID-19 infection, said Dr Sewa.
Still, the team decided to let
Ms Khoo’s baby develop further
in the womb. To give mother and
baby the best chance of survival,
Ms Khoo was deeply sedated and
put on extracorporeal membrane
oxygenation (ECMO) therapy.
ECMO takes over the function
of the patient’s lungs and heart,
allowing the infected lungs time
to recover. Blood is taken out
through the big veins, passed
through the artificial ECMO lung,
where carbon dioxide is taken out
and oxygen added before being
pumped back into the patient for
circulation through the body. For
Ms Khoo, getting enough oxygen
would also help prevent her foetus
from suffering oxygen deprivation.
Ms Khoo spent six days
supported by ECMO, and another
day on the ventilator before she
was able to breathe well on her
own. Not long into her recovery,
Ms Khoo began to have labour
pains and delivered her son at
27 weeks. Although still very
early, the extra weeks spent in
the womb to develop naturally
increased the baby’s survival odds,
said Dr Tan.
Although baby Yohanne
weighed just 789g at birth, he
was unaffected by his mother’s
COVID-19 infection and ECMO therapy, and was cared for at SGH’s
neonatal high-dependency ward.
Ms Khoo, however, experienced
chest pains, difficulty in breathing,
and trembling hands even after
recovery. She also needed physical
and occupational therapy to relearn
daily activities like walking,
writing and getting out of bed.
“I don’t think pregnant mothers
would want to go through what I
did. I had no choice but to birth
my baby three months early
and let my baby suffer,” said
Ms Khoo. The 37-year-old described
her one-month stay in isolation
at SGH without her family by her
side as “not an easy road”. During
her illness, the now-mother of four
worried about dying and leaving
her children behind.
Looking back, she wished
she had been inoculated early,
instead of considering having one
only during her second trimester
of pregnancy. “If I had been
vaccinated, I think my body
would have been able to fight
the virus,” Ms Khoo said.
Like Ms Khoo, Ms Vanessa
Rickard also became infected
with COVID-19 during her
pregnancy. Her experience
was not as harrowing,
but the loneliness and
fears she experienced in
hospital isolation made her
determined to encourage
other pregnant women
about early vaccination. Her
family was not able to visit her;
furthermore, her husband, elder
son and helper also contracted
(Photo: Ms Vanessa Rickard)
When Ms Rickard, then 36,
became pregnant during the
early days of the pandemic, little
information was available about the efficacy and safety of the
vaccine on the unborn foetus.
Mothers are understandably
concerned about how the vaccine
might affect their foetus, such as
the potential risks of infection,
foetal abnormalities or preterm
labour, said O&G’s Dr Tan.
Indeed, Ms Rickard had many
of these concerns. “I thought I
would just wait till I gave birth
and get vaccinated after that.
I wasn’t sure what effects the
vaccine would have on my baby,”
It was only in the second
half of 2021 that studies started
becoming available showing that
vaccination was safe for pregnant
women, and that it does not
increase the risks of miscarriage,
preterm labour, or small, growthretarded
babies. “In fact, it is
COVID-19 itself that will increase
the risk of pregnancy-related
complications if the mother gets
very sick,” said Dr Tan.
Ms Rickard tested positive
for COVID-19 and was admitted
to SGH’s isolation ward in
mid-August. Although her
symptoms were relatively mild —
runny nose, dry cough, fatigue and
loss of smell — she was already in
her ninth month of pregnancy.
A week later, she felt labour pains
and delivered her baby son. She
was the first patient to give birth
in an SGH isolation ward.
At the time, Singapore had
begun seeing a marked increase
in community COVID-19 cases.
At SGH, the number of pregnant
women infected with COVID-19
rose in tandem — from none in
July to more than 10 in August
and September, said Dr Benjamin
Cherng, Senior Consultant,
Department of Infectious
“Almost all were unvaccinated,
and a few were partially vaccinated.
Vaccination rates among this cohort
of pregnant women who came
through SGH then were extremely
low,” said Dr Cherng.
The vaccine has since been
shown to be safe for both mother
and foetus. “The benefits [of
vaccination] certainly outweigh
the risks of COVID-19 and its
complications,” said Dr Cherng.
Interaction between newborn
babies and COVID-positive
mothers has not been shown to
cause an increase in the incidence
of neonatal COVID-19 infection,
but Ms Rickard chose to be
separated from her son for two-and-
a-half weeks after delivery.
She saw him only via video call.
As with new mothers who have
had their vaccination, the breast
milk of COVID-positive mothers
is also safe and beneficial for
babies. Moreover, the Ministry of
Health (MOH) said the breast milk
of vaccinated mothers may help
protect babies from COVID-19 due to antibodies in the breast milk.
“Initially, when the pandemic
started, breast milk was not given
to babies, but now, the evidence is
pretty clear that breast milk is the
best and gives protection for the
baby,” said Dr Sridhar Arunachalam,
Consultant, Department of
Neonatal and Developmental
Medicine, SGH. The hospital has
also been encouraging mothers to
breastfeed their babies.
MOH added that no vaccinerelated
side effects have been
reported in the babies breastfed
by mothers who received the
vaccine while breastfeeding.
As infections in Singapore and
elsewhere are climbing again
with the advent of the Omicron
variant, the need to be vaccinated
is ever more urgent.
“Even one dose [of a vaccine]
before delivery is better than
nothing,” said Dr Tan.
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