People across the world have been trying to trick their pals with a variety of April Fools' Day pranks today.
Some have been funny and clever, while others are just a bit weird.
But midwives are urging people to avoid one common type of prank, claiming it can cause further heartbreaking to people going through a terrible time.
They've asked people not to post fake pregnancy announcements, saying that "one in four of your friends will have lost a baby".
A post highlighting the potential upset has been widely shared on social media in the lead up to the day.
It shows a pregnancy test with the words: "This is not an April Fools Joke! 1 in four of your friends will have lost a baby and 1 in 6 will be suffering with infertility.
"Pregnancy is not a joke, be more creative this April Fools!"
Liz Wilkes, from My Midwives, told MailOnline : "Women can be quite fragile around the issue of pregnancy and something like a joke pregnancy announcement can end up being a painful reminder of something they are struggling with.
"Women who are experiencing fertility issues, have had a miscarriage or have had to terminate a pregnancy may have had to keep this to themselves, will be feeling emotional.
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"To see something like [a joke announcement] on Instagram of Facebook is really disrespectful."
Miscarriage is the loss of a baby during the first 23 weeks of pregnancy and normally can't be prevented.
They occur for a number of reasons, but it is usually not possible to identify what happened. Most are not caused by anything the mum has done.
For advice on miscarriage, visit the NHS website .
