I found out what i was having at 18w at the hospital & reconfirmed it at my actual sonogram appt at…

I found out what i was having at 18w at the hospital & reconfirmed it at my actual sonogram appt at 19w. My doctor gave me the referral for my sonogram & told me to call & make an appt within 4w but I believe I made it 2 or 3 weeks ahead of time. Idk if everyone else has to get a sonogram done somewhere else with thier doc referral but if you do just know you don't have to actually wait until the time they tell if you already have ahold of the referral...