yep i think it is personal choice and after the 1st tri with the folate to help with neural tube defects it was explained to me that a large part of it will be about my well being and good feeling - the baby will take what it needs from me, and i may find my stored depleted... so i still take them but i must admit i was fanatical about it to start and the last few weeks i have been slacking off a bit and forgetting... that reminds me i had better take one now!!
so if you are feeling good i am sure you are fine, if your energy levels drop or you feel low etc then perhaps look at your diet first and then think about supplements if you need them.