how long should i really wait to announce?

I’m 5wk4d today and it’s my fiancé and I’s first child together. everyone in our family and friend group knows that we wanted to have kids, everyone’s very supportive so I’m just curious how long I should wait to tell people? He wants to tell our families as a christmas gift (which sounds sooooo sweet and memorable as it will be the first grandbaby and great grandbaby on both sides of our family) but I’m nervous since it’s so early… any advice? Thank you!!