Progesterone suppositories

Meredith • Mother to my rainbow baby girl 10/21/16 and 1 on the way due 1/4/19 🌈🌈

TTC #2 and just got my progesterone refilled (used with #1 - finally successful after 4 losses!) but I don't remember, do I start taking after BFP? Or after ovulation? Anyone know?