how to tell parents i’m pregnant?

i’m 19 years old and i live on my own. i’m not that close to my parents and i don’t tell them anything about my love life, they think i’ve never had a boyfriend let alone do anything sexual. i’ve been keeping my boyfriend a secret from pretty much the whole entire family. my parents split when i was young and so i’ll have to tell each side of the family separately. how do you think i should tell them? i think i want to tell my mom first but i have no idea how to bring it up. how did you tell your parents?