Toxins & estrogens release when burning fat... safe for baby?

Hi guys. I'm wondering if anyone knows the answer to this. We store estrogens and vitamins and toxins in our fat. Is it safe for the baby for you to lose a bunch of weight (say you're obese and you do need to lose weight) if you have eaten poorly in the past, or are just obese so you have excess estrogen, and those things will be released into the bloodstream?

Bonus question: whose body gets prioritized with energy distribution? You eat a certain number of calories--do the eaten calories go to you first, then the baby, or vice versa? If you eat too little, who is supplemented by the energy from burning fat reserves?