What Are Pros And Cons Of Embryonic Stem Cell Research?

It can't 'hurt' you. The reason most people don't like it is because they don't know very much about it. People think it involves growing embryos, killing them and harvesting their stem cells, but it doesn't. Stem cells can be taken from artificially inseminated (laboratory grown) cells, before they even nearly develop into anything that can think, sense or feel. People also don't like it since they think it'll be the start of us growing new things like 'clones', and 'designer babies' (where we choose what our baby would look and be like.)
The advantages are it could enable use to grow new organs for people with disease, since stem cells are cells which haven't been 'grown' into a certain cell yet, so we could grow them into anything we wanted like a liver, heart or kidney. They could also help cure many other diseases. I'm not an expert or anything, but that's a general overview.