Gimme a Break! (1981) : 1x17

Samantha and her friend Scottie from her baseball team decide to sit on the couch and watch some television. As they are intimidated by a love story, they talk about kissing, and they decide to try it. As Julie and Katie walk in on them, they suspect that they have been fooling around, and when the cheif finds out, he tells Samantha that after she kisses a boy she will end up pregnant. Due to this remark, Samantha mistakes that she can get pregnant from kissing, and seeks help from Julie, Nell, and Grandpa, but they aren't very good at it. Finally, when Nell sees Samantha crying in her room, she tells her that she thinks she is pregnant, and Nell tells her never to beleive what her father says because he is full of it, and she decides to teach her the facts of life.