The father's guide
The 20-week scan: what it checks, and what to ask
Most fathers arrive at this appointment expecting a picture and a sex reveal. It is a screening scan, it has a specific list, and knowing the list changes what you hear in the room.
What the 20-week scan is for
It checks for signs of 11 different conditions affecting the baby's health and development, and it also looks at growth, at the placenta, and at the blood flow through the uterus. It is a medical examination that happens to produce an image, not an imaging session that happens to be medical.
Source: NHS
The 11 conditions it looks for
Reading this list is uncomfortable, and it is also the reason the appointment exists. Most scans find none of it.
- Anencephaly
- Open spina bifida
- Cleft lip and palate
- Diaphragmatic hernia
- Gastroschisis
- Exomphalos
- Serious cardiac abnormalities
- Bilateral renal agenesis
- Severe skeletal dysplasia
- Edwards' syndrome
- Patau's syndrome
Source: NHS
What the scan cannot rule out
This is the sentence to carry out of the room with you: "Some conditions can be seen more clearly than others, so the scan may not find everything." A clear scan is good news about a specific list. It is not a guarantee, and it does not replace telling the midwife about symptoms later on.
Source: NHS
How long it takes, and who can come in
Roughly 30 minutes, and longer if the baby is moving a lot or lying awkwardly. A long appointment is usually a baby in the wrong position, not a problem found — worth knowing before you spend twenty of those minutes reading the sonographer's face.
You may bring someone with you, but most hospitals do not allow children in the room, and policies differ. Check with the clinic beforehand rather than arriving and finding out.
On the sex: you may be asked whether you want to know. It is a question, not an automatic part of the report, and the two of you should have answered it between yourselves before someone asks it out loud.
Source: NHS
If something is found
You may be offered further scans and tests, such as amniocentesis, and a specialist will explain the results and what they mean for her and for the baby. Nothing is decided in the scan room, and you are not expected to have an answer that day.
The practical thing you can do is write down what is actually said, including the words you do not recognise. Under that kind of news almost nobody retains a conversation accurately, and the spelling of one term is the difference between reading about the real condition afterwards and reading about a different one.
Source: NHS
Put the appointments where you will both see them
Nawah's appointments screen is shared once your accounts are paired, so the scan date is not a message that scrolled away in a chat. The father's view carries the same week and the same dates as hers.
Get Nawah freeCommon questions
Can they always tell the sex at 20 weeks?
The NHS says you may be asked if you would like to know — it does not promise an answer. The scan's purpose is the 11-condition list, and the baby's position governs what is visible. Treat it as a possible bonus rather than the point of the appointment.
The scan was clear. Does that mean the baby is healthy?
It means no signs of those specific conditions were seen. The guidance states outright that the scan "may not find everything" and that some conditions show more clearly than others. It is strong reassurance about a defined list, not a clean bill of health for everything.
Should I take time off work for it?
This page cannot tell you what your employer allows. What it can tell you is that the appointment runs about 30 minutes and can run longer, that results may be discussed on the day, and that it is one of the few appointments where a second person hearing the same sentences has obvious value.
Sources
- 20-week screening scanNHS · retrieved 2026-08-22
This guide is general information, not medical advice. It does not replace a doctor, and it knows nothing about your particular pregnancy. If something feels wrong, contact your doctor instead of waiting for the next scheduled visit.
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