It seems simple: an egg + sperm = one embryo. But if your sperm is "few, vague and abnormal" and your woman is premenopausal at age 37, things start to get complicated.
The film details the adventures and misadventures of a group of patients with OCD, all of whom have an appointment with their doctor at the same time. However, the doctor is delayed by a flight, forcing them to deal with each other's quirks and compulsions.