Measure from LMP or IUI Date?

Shauna - 💙❓

Going off my LMP, I’m 5w today. Going off my IUI date, I’m 5w2d. This confused me because it didn’t make sense but then I read that if you go off your IUI date, with the presumption that you ovulated that day, you add 2 weeks to it to get how far along you are. Have others done this? Did the baby end up measuring closer to the date of your IUI or your LMP? Just curious 😊