Proteins in fiancés sperm?

Sarah

So to sum this story up my partner had a gf before me and they tried for two years and had no baby. Right around after they broke up and he met me, she got pregnant a month later and sent him a picture of a positive pregnancy test. Me and my fiancé have been trying for three years, no baby yet and just starting medication for a baby. The doctor said his sperm is fine but he had lots of proteins and debris and his sperm. What does this mean?