A 19-year-old woman came to me, confused about pregnancy. She had been dating a boy and had indulged in mutual masturbation. She said that during the act, the boy ejaculated near her private parts. She was sure that both of them were fully dressed. She worried about getting pregnant. I calmed her down. She was advised to wait for her periods.
Her urine pregnancy test was negative. A woman can only become pregnant after an unprotected peno-vaginal intercourse. The sperms need to be deposited in the female genital tract. Other factors too play a role. The chances of sperm entering the vagina with the clothes fully on are minimal.
The chances of pregnancy in this case seemed to be a pipe dream. She was requested to keep a condom handy. The condom may offer additional benefit in the form of protection from unwanted pregnancies and sexually transmitted diseases.