You may try juicing red beets for iron, or juicing greens - that way you take in more minerals (and less fibers) and more phytonutrients. You can build up faster by getting about 1 l of juice every day, or at least 500 ml. You need a masticating juicer though for the greens (I aslo use it for beets and cabbage - mine is Greenstar, electrical).
Or you could try Floradix or Floravit for Iron if you find these products - combination of juices and added iron.
Another thing - about the miscarriage, for further use - low magnesium can sometimes cause miscarriage (through uterine spasms and contractions). Mg is given for ex in order to cancel premature contractions. Most ppl now are Mg def due to soil depletion.
It is probably a good idea also to try the Moreless drink, about which Chiron talked on this page.
You may try a second fast and interrupt it if you find it hard. It is probably not dangerous trying - how many days will you have between the two?