I'm taking both, my doctors told me it was no harm. (Especially in the first trimester) They also said if I wanted to on my own decision, I could ween off the folic acid mid-pregnancy
that's what made me ask because the parentals I bought has more folic acid milligrams than the pills alone
I was told that my body would only absorb what it needed and got rid of the rest. It all depends on your body and doctor.
I'm taking both because I'm diabetic and don't wanna risk birth defects