18 weeks pregnant: the detailed anomaly scan in Singapore

At 18 weeks pregnant, your second major scan is close. HealthHub puts the detailed anomaly scan at 18 to 22 weeks, and KKH does its 20-week fetal anomaly scan between weeks 18 and 21. It checks your baby from head to toe for structural problems, and it's often when parents find out the sex.

What the detailed scan checks

KKH describes it as a scan that looks at your baby from head to toe to find any structural abnormalities. It also screens for a low-lying placenta. HealthHub adds that it checks your baby is growing well. NUH schedules its detailed scan at 20 weeks.

No scan picks up everything. KKH lists what can make problems harder to see:

• a larger body size
• previous surgery
• the position your baby is lying in
• a low amount of amniotic fluid

The scan also isn't a test for Down syndrome on its own: KKH says up to half of babies with Down syndrome have a normal scan.

Boy or girl?

The sex can usually be seen at around 18 to 20 weeks, HealthXchange says, but only with a clear view of the genitals, so it isn't guaranteed. If your baby isn't cooperating, you may have to wait for the next scan. HealthHub calls the scan fairly accurate for sex, and notes you can only be 100% sure after the birth.

Your baby at 18 weeks

Your baby may now be able to hear, HealthXchange says. The bowels have started working, and meconium, your baby's first poo, is building up; it should only come out after birth.

This is also when many women feel the first movements. HealthXchange says most first-time mums notice them between 18 and 20 weeks. KKH says some describe them as a wave of bubbles, or the flick of a fish's tail.

What's due in Singapore at 18 weeks

Going private? NUH offers private patients an antenatal package from 20 weeks that covers consultations and the 20-week and 32-week scans. Our guide to hospital maternity packages and the delivery cost calculator help compare.

KKH's planner has one more tip if you're getting the nursery ready: choose wallpaper over paint, since household paint can contain low levels of toxic chemicals and there's no research on painting in pregnancy. Our prenatal check-ups and scans guide lists every scan to come.

When to call the hospital

Bleeding, fluid leaking, painful tightening, a bad fall, chest pain, fainting or breathlessness need a same-day check.

KKH's Urgent O&G Centre, at Basement 1 of the Women's Tower, takes walk-ins 24 hours a day for early pregnancy problems such as pain and bleeding. Under 16 weeks, if the bleeding is minimal or the pain is mild, its Early Pregnancy Assessment Unit can see you the same or next working day by appointment. If you're booked with another hospital, call its O&G clinic or go to its emergency department.

Frequently asked questions

When is the detailed anomaly scan in Singapore?

Usually between 18 and 22 weeks, HealthHub says. KKH does it between 18 and 21 weeks, and NUH at 20 weeks.

Can the anomaly scan miss problems?

Yes. KKH says detection is never 100%, and body size, previous surgery, your baby's position and low fluid can all make it harder.

Will I find out the sex at the 18 to 22 week scan?

Usually, if your baby is lying so the genitals can be seen. It isn't guaranteed, and HealthHub notes you can only be 100% sure at birth.

18 weeks pregnant is how many months?

About four and a half months, counted from the first day of your last period.

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