from what i have read and learned, the current thinking is to do nothing during pregnancy. and considering the loss of your baby during your last pregnancy, i would be especially concerned about any sort of stimulation of your nipples during pregnancy.
i believe that wearing nipple shields in the bra (or maybe they are called something different... correct me if i'm wrong, someone!) are sometimes recommended just after baby is born to help the nipples evert. some women also have success using a breast pump for a few minutes before trying to nurse the child so that baby has a better "target". some women with inverted nipples have babies that have no trouble at all latching on. i think it will really depend on your baby and your baby's nursing personality.
most importantly, you CAN breastfeed with nipples that are inverted. many women with nipples that are inverted find that the issue corrects itself with baby being at the breast. find a good Internationally Board Certified Lactation Consultant (IBCLC) in your local community (many hospitals have them on staff, and some even work independently or in clinics) that will help you achieve your goals for breastfeeding. interview more than one while you are pregnant, and be prepared to have them come the same day your babe is born and again regularly until you are confident in your breastfeeding. join your local La Leche League chapter and go to some meetings while you are pregnant www.lalecheleague.org
wishing you a peaceful and healthy pregnancy and a safe and beautiful birth...