Doogie, Wanda, Vinnie, and Jenny are at a restaurant when Vinnie tells them that a couple that just walked in has had sex. Vinnie tells Jenny that he thinks that sex is a beautiful thing, but Jenny tells him no. Vinnie asks Doogie how long he and Wanda have been going out and Doogie tells him four months. Jenny tells them that everyone thinks that they are a perfect couple and Vinnie asks them what they are waiting for. In the car, Doogie asks Wanda why they aren't having sex and that the average age for girls to have sex is 16.2 and for boys is 15.7. They decide that they should do it and Doogie tells Wanda that his parents are going to a medical banquet on Friday an Wanda agrees to "do it" on that day. They agree that it is going to be good.
At the hospital, Doogie helps a mother who is giving birth. When Doogie gets home, Vinnie is there waiting for him and congratulates Doogie on deciding to have sex. Vinnie tells Doogie that everyone knows that they are going to have sex. Vinnie tries to help Doogie for his exciting night by giving him a record to play on that certain night. Doogie checks in on the woman who just had a baby and realizes that she is still going to school and lives with her sister and there is no guy in her life. Doogie and Wanda both read The Joy of Sex to get ready for the night. Doogie cleans his room, and both of them put on their best clothes for the night. Vinnie walks in and notices Doogie's clean room and tells him that he is impressed with Doogie cleaning his room. Doogie's mother comes in Doogie's room and tells Doogie that she will be leaving and will be home by midnight. Vinnie is worried that Doogie's mother knows what will happen. Vinnie gives Doogie a condom, but is interrupted by Doogie's father bellowing for Doogie to come downstairs. Doogie's father shows a baby that was delivered to the house with a card in the car seat with Doogie's name on it.
Doogie's mother croons over the baby, but Doogie's father tells her that they can't have another baby. Doogie tells his father that the mother just needs a few days and that he doesn't want to talk to the police. Doogie suggests talking to the social worker and tells his parents to go to their banquet and leave the baby with him. When they leave, Doogie's mother tells him to change the baby's diaper and when they open the door to leave, Doogie's father sees Wanda and asks her what they planned on doing. Doogie, Wanda, and Vinnie change the baby's diaper and all are disgusted by the whole ordeal. When Doogie brings Wanda home, Doogie apologizes to Wanda for their plans being interrupted by the baby. Wanda tells him that she understands. Doogie tells her that she is beautiful and they discuss how excited they were to have sex. At the department store, Doogie and Vinnie are searching for lingerie to buy Wanda and they are blown away by the items for sale. Doogie is at the hospital and is playing with the baby when the mother comes into the room and asks why she is there. The mother wants to take her home, but Doogie tells her that they have to talk. Doogie tells her that she abandoned a baby and it is not something that you just forget. The mother tells Doogie that she was needy and she didn't really think that a baby would be so much trouble. The mother tells Doogie that she is thinking about adoption so that the baby can have two parents and not a kid for a mother. Doogie takes her to the office to find someone to help her. At home, Doogie has the stage set for the perfect seduction, they just seem to sit on the bed not doing anything. When Wanda stands up and starts taking her shirt off, Doogie talks about what the books tell him about foreplay, but Wanda is too concerned with Doogie's parents catching them. Wanda asks him to turn a picture of his parents around and they start kissing, but Doogie backs out and they both express their unwillingness to have sex. Wanda tells him that she just wanted to get her first time over with since everyone keeps talking about it. As they realize that they are nerds, they decide to talk about how sex changes people and the pressure that comes with having sex. Doogie tells Wanda that he doesn't want to risk their relationship by having sex, and they will only have sex because they want to, not because other people want them to. Doogie shows Wanda his personal journal and explains that he has never shown it to anyone else. Doogie writes in his journal that they decided to not have sex and that he loves Wanda.