11.5 weeks post-vasectomy

Here is our story...
DH was born with 1 testicle. The other was not even formed..dr's called it scar tissue. The scar tissue was removed at birth. At this time the dr's told his parents that he only had a 50% chance of fathering children.
DH has 2 daughters with his ex wife.
I have a son with my ex husband.
We just had our second child together (7 weeks ago)
We decided that it was best to have him have a vasectomy... which was performed 11.5 weeks ago.
He just got off the phone with the dr....after the second "sample" he is still fertile.
We are banging our heads against the wall. The doctor told us that after 30 ejaculates the "swimmers" should all be gone. We have kept track..we are close to 50 ejaculates. Is there anyway the dr could have cut something instead of the vas? DH went in last week and the dr said the ends are still quite far apart. Just not understanding why in the heck the swimmers are still there..when we were working with one testicle to begin with. Tweet