Maternity Leave

When did you start maternity leave? I'm FTM currently 21 weeks and know I can request my leave dates soon. I have no idea when to start it!

I was thinking about 38 weeks as we have a big project I'd like to see through, is that too early or too late?? I don't wanna start mat leave and then be bored waiting for baby to get here 😂 but at the same time I am already struggling with the hours!