A splash conception
is when a man ejaculates outside a womans vagina, but some of it gets into the vaginal secretions from the womans body, and swims its way to victory. Looked at under a microscope the secretion have structure and there are chemical trails that tell the sperm which way to go, so it's just a question of having a longer swim than normal.
Women can therefore end up pregnant whilst still technically virgins.
Ironically, about 10% of the women who engage exclusively in unprotected anal sex, (e.g. those trying to avoid getting pregnant), end up pregnant this way each year.