There is a percentage of failures in these procedures but it does seem very unusual that both of you would have this problem.
Did your boyfriend have the follow up sperm count test to be sure his vasectomy was complete? He should definitely do so now either way.
I assume you had a positive pregnancy test and are absolutely sure you suffered a miscarriage. We don't know why sometimes tubes are able to grow back together. It's kind of ironic when so many women can't become pregnant and others do in spite of such serious measures to prevent it.
You should consult with your doctor at this point. He may want to do studies to determine what is going on with you and counsel you on your next move from here.
The answers in online forums are for information only and are not intended to substitute for medical advice and care. Please see your personal health care provider for further evaluation of your individual case.
Debbie Miller, RN