The purpose of the scan is to check the health of bub. If bub has very serious health issues, then you are given the option not to continue with the pregnancy.
The limit for making that decision is often around 20 weeks, so it can be better to have the scan before then.
I hope I haven't upset anyone. I know it is the last thing any of us want to think about. It is just a very sad, but practical aspect to consider for timing your scan.
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