Scarlett Lynsky, CD(DONA), ICCE Answers
Disclaimer: I'm a doula and childbirth educator, not a medical provider.
But in the interest of keeping anxiety down for those pregnant people who are anxious about providing optimal nutrition to the baby, here's my take. I often think of prenatal vitamins as more for the person carrying the pregnancy. The baby gets what the needs first, but then there may be little left for the pregnant person during or after the pregnancy! So, for those people that haven't been able to keep prenatals down, or found discovered their pregnancy a bit later in the game, don't worry, it's probably just fine.
In my experience as a doula, anemia is really common, so make sure you talk to your doctor or midwife about absorbable forms of iron and other blood builders to keep up your energy.