Dealing with anemia in pregnancy?

Iron makes your stool turn black. That's normal and expected. It causes loose motion in some people and constipation in some others.

Often using a different brand of iron supplement helps to avoid nausea. Maybe you can ask your GP to prescribe the same supplement by another company.

Make sure you drink plenty of water (as much as you can without throwing up). Not sure if you have Asian/African shops where you live. There is a variety of small sour banana that can help with constipation if you take 2-3 at night. Something that worked like miracle for me is cassava/tapioca. But you need to know how to cook it safely, because in natural state it is not good for you.

But any fibrous food should help. Some varieties of banana are used to stop loose motion. So don't just pick any kind. To increase iron in your body, have spinach, beetroot, dates, pomegranate, etc. Most leaves help. Just make sure the leaves you choose are pregnancy-safe. Date syrups are also available in the markets.

I couldn't take iron for months because of vomiting and then when I could hold it down, I had constipation so bad I was ready to go see my gynecologist. But it's mainly cassava that helped me. I was lucky enough to have my mom cook it for me. You gotta drain the water you cook it in several times, and then add shredded coconut and cooking oil to combact the negative things in it. I think fish also helps to compensate for the negative elements.

Good luck! I hope you aren't still struggling. All that you experience is very normal and common.