About.com states that genital contact without penetration can result in pregnancy although it is very rare. Pregnancy can occur during any instance when sperm, whether in ejaculate or pre-ejaculatory fluid form, has contact with the vagina.
About.com states that there are at least 300,00 sperm in pre-ejaculate fluid with the ability to swim, so pregnancy can occur if just one sperm near the vagina gains entry.
The United Kingdom's National Health Services also states sperm on fingers being placed in or near the vagina is another possible way of conception without penetration. These occurrences are very rare due to sperm being unable to live outside of the body for a prolonged amount of time.