It is quite possible (although somewhat unlikely), as you can get leakage from one hole to the other.
There is even a case where a woman was engaged to a man, but refused to have sex before marriage, however she was secretly given blow jobs to the man's brother. The engaged man caught the two together and in a fit of rage, grabbed a long knife and stabbed his (presumably ex) fiancée through the stomach and into her womb, she was hospitalised, but recovered and was later found to be pregnant, even though she had never had penetrative sex. It is speculated that she had some seamen in her stomach when she was stabbed, and a tiny amount got onto the blade and this then got her pregnant.