Hello Mam, I Had An Abortion That Is Almost 4-5

Hello mam, I had an abortion that is almost 4-5 months back. That was a missed abortion as when I was 11weeks I started spotting and when I diagnosed I was told that the scanner shows that the fetus growth stopped on 7th week and she cannot hear any heartbeat. May I know what causes such problems and how to avoid it in future? I had also some test of harmonal level and everything I found in me was normal. Is the male sperms are required to be tested as well?? My hubby had a vercocele surgery when he was a some 11yr old. Does it cause problems in harmones? I also often noticed that if he has sex on daily basis his ejaculate less sperm. Please explain me if anything is required to be done for it. One more question is, soon after my pill abortion I had started bleeding and that lasted for almost 25days. After that after 12days I again got my period and it retained for 10days similarly its four months now and I'm getting period on proper time but it lasts for 12 days or so and I also feel some discomfort in my abdomen sometimes. Is it normal?