Your pregnancy is not full-term yet, so why is your cervix dilating before the expected due date? We ask the doctors if you can prevent the premature birth.
Most mums-to-be expecting a normal labour look forward to the magic number 10 – that’s when the cervix, or neck of the womb, is fully dilated by 10cm and their babies are ready to be delivered.
For others like first-time mum Kellyn Mong, dilation comes too early for comfort. The account manager was only in Week 28 of her pregnancy when she found out her body was already showing signs of labour.
A routine check-up revealed the cervix was already 1cm opened, a possible indication of preterm labour.
In a normal pregnancy, the cervix only starts dilating after about Week 37, according to Dr Tan Eng Kien, a consultant at National University Hospital Women’s Centre.
“A woman who’s not in labour will have a cervix that’s long and closed. When she goes into labour, the cervix ‘ripens’, shortens and opens up,” he explains.
Kellyn, who had led a healthy and active lifestyle, says she found it hard to believe her doctor that she was experiencing dilation.
“The news came as a shock,” shares Kellyn, who was given medication to strengthen her cervix and ordered to rest in bed.
“Up until then, my pregnancy had been so normal. I had continued working and doing housework. I didn’t even experience morning sickness.”
So why do some mums-to-be experience the condition before their little ones are ready to see the world?
According to Dr Christopher Ng, an obstetrician and gynaecologist at GynaeMD Women’s and Rejuvenation Clinic, one of the most common causes of early dilation is cervical incompetence, a serious complication that occurs in up to 2 per cent of all pregnancies.
“A weakened cervix is unable to remain closed during the pregnancy and begins to dilate before the expected due date,” explains Dr Ng.
This puts the mum at risk of premature labour or miscarriage. As there are no warning signs, most women are often caught unawares until they go for their routine monthly check-up.
While Kellyn was lucky enough to have detected early dilation in time, Eliana Chan wasn’t as fortunate.
Because of a weak cervix, the accounting officer lost her babies when her first two pregnancies ended up in miscarriages.
Noting her history, Dr Ng, who was her obstetrician, performed a cervical cerclage – a procedure during which a stitch is placed around the cervix to prevent early dilation – during her third pregnancy.
“I was also put on bed rest for a week after the surgery. This time round, I was able to carry my baby to full-term,” says Eliana.
Can you prevent an early labour?
Exactly what causes an incompetent cervix is unclear. But several factors can increase your risk.
For instance, some women may be born with abnormal cervix or weaker connective tissues around the cervix, says Dr Ng.
He adds that those who have had cervical tears from a previous childbirth or surgical cervical procedure may also have a weaker cervix.
Dr Tan adds that other risk factors include smoking, which increases a woman’s chance of preterm labour, and illnesses, such as urinary tract infections.
Those who have had preterm births are also more likely to deliver early with subsequent pregnancies.
If you have a history of preterm labour or second trimester miscarriage, see an obstetrician early when you’re pregnant again for regular monitoring, Dr Tan advises.
If your doctor notes a shortened cervix during an ultrasound scan, she may give you medication like progesterone to prevent early labour.
As in Eliana’s case, your doctor may also perform a cervical cerclage to prevent early dilation if you have a weak cervix. After which you may need to go on bed rest – in the Trendelenburg position, the body is laid flat on the back with the feet higher than the head – to lessen pressure on the cervix.
“Women with cervical incompetence should refrain from sexual activity or physical pursuits. In some cases, they are advised to go on bed rest, but it isn’t a proven remedy for preventing premature birth,” says Dr Ng.
To stop the cervix from dilating further, Kellyn was prescribed medication to strengthen it. Her doctor also ordered bed rest at home. An active, go-getting type of person, she initially found this a bore.
“To be honest, I didn’t really listen to my doctor at first. I continued working from home, and did light housework like laundry and cooking. These chores are minor to me, but my gynae certainly didn’t think the same,” she says.
But she changed her mind after a subsequent check-up two weeks later.
“After this period, I didn’t dilate further but the doctor said my cervix was still ‘soft’. Reality hit home and I decided I would literally stay in bed from then on. I wanted my baby to be healthy,” she says.
Kellyn eventually made it past Week 39 and delivered a healthy 3.42kg boy.
Until now, she isn’t sure what caused her condition, but believes that she wouldn’t have made it so far without her doctor’s prescribed bed rest.
“I was probably stressing myself and doing too much during my pregnancy. Although it’s not easy to confine an active person at home, the rest certainly helped me to slow down,” she says.