Some research came out in October about vitamins that lead me to stop taking mine (except for folate). For the first two weeks of November I felt awful. I had no energy. I started back with everything I had been taking before and started to feel much better within a couple days. I probably should have been more scientific and started one at a time to see what really needed but I was so miserable I didn't want to waste any time. It didn't help that I had a lot of food aversions at the time.
multi-vitamin/prenatal (when I found out I was pregnant I had just started a big jar of multis. I didn't want them to sit there for a year so I got the b-complex to up the folate. I just started prenatals.)
Calcium + D (I really struggle to get enough calcium. I can't have any for breakfast and usually for lunch either. I'm not fond of drinking milk. I could not figure out a way to get in enough food based calcium in just an afternoon snack and dinner. There is research on pregnant women and calcium supplements so I'm keeping it for now.)
Iron (I had not heard that Iron affects how thyroid meds are absorbed. I've read that calcium can keep iron from being absorbed so I switched to taking my iron supplement in the morning with my meds. It has only been two days but the results are a much higher energy level for me. I was slightly anemic last pregnancy.)
Biotin (This is the only thing I feel silly about. After my last pregnancy I lost a lot of hair and ended up with much less than I started with. What grew back was brittle and a different consistancy. My mother who was a hospice nurse for many years and worked with many patients who's hair was impacted by chemo suggested biotin. )