Best prenatal vitamin?

JC
So I've gotten my BFP and I'm over the moon excited! But I have a question - are all prenatal vitamins created equally?
I've been taking the Target brand Up and Up prenatal vitamins since March, but am wondering if there are "better" ones out there. Does each brand of prenatal vitamin have to contain a certain amount of each type of nutrient? 
What are your favorite prenatal vitamins?
Thanks!!