I don't take anything. When I went to my first appointment with my gynaecologist (I'm in Germany) at 11w + 0 (couldn't face any earlier due to being off this world with sickness, even getting upstairs to bed was a chore), his first question was, 'Do you take vitamins?' 'No.' He gave me two free boxes of these huge vitamins (they must be designed by men, I'm sure) with an equally huge price. Free packets mean he has been visited by a pharmaceutical representative, and as I have inside knowledge of market studies in the pharmaceutical industry, I can see through that in a second. Needless to say, I haven't taken them as they are huge and they frighten me. Besides we mainly cook from scratch.
At any rate, at my next scan about 3 weeks later, he said he was 'satisfied' and 'contented' with how baby looked, and I've only been taking tiny folic acid tablets that contain some vit B12, B6, D3 and iodine. Iodine is also important apparently, as is vit D.
IMO pregnancy supplements are a waste of money unless you eat absolutely nothing of fruit and veg (incl. juice and things) or you are completely malnourished.
However, vitamin B deficiency seems to have to do with morning sickness, as all over-the-counter medication for morning sickness here seems to contain them.
Anyway, I wouldn't take anything that made me feel ill. Sorry.