Prenatals after 12 weeks

Hello, what prenatals are we taking at 18 weeks? I was taking ‘Heathy Start’ vitamins given to me by midwife (Scotland) which contain folic acid and vitamin D. After 12 weeks I changed to Pregnacare for pregnant women. I’ve been getting bad wind/ sore stomachs and my mum pointed out the iron and lots of other ingredients. She said I may be fine not to take a prenatal now (I’m 18 weeks) as we get our vitamins from food. Any advice??