Durring pregnancy you need to be taking 1000 mcg or 1mg can be noted either way on the bottle. If you are using a doctor prescribed prenatal it will have the correct amount.
For my wife, I made sure her vitamin holder had her "womans one-a-day, iron supplement, folic acid supplement, and the enfamil lipil dha/ara supplement for preg and nursing moms"
it is not clear if the enfamil supplement is needed or not but the ob gave us a sample and knowing that the omega 3 vitamins are very necessary, it only made sense for us to use them. If you are not too sure if you want to take them or not, you can call enfamil at 1-800-baby123 and ask them to send you information and a free sample of the formula and those lipil supplements. They have been fantastic for us. I call about once a week and they are always happy to help.
Also on a sidebar note, make sure you go to similac, enfamil, nestle' good start, pampers, huggies, and any other baby thing you will be using and register with them. You will get loads of freebies and loads of gift checks to help you buy formula and diapers. So far, similac and huggies have been the most generous as far as giving money (coupons/gift checks) and enfamil has been the tops as far as free samples and advice.