Dolphins, like almost all mammals, give birth to live young, and nurse them with mammary glands, though it boggles the mind to imagine nursing underwater. But the birth of a dolphin starts long before his babyhood; it starts with how Mom and Dad first met.
Most of what we know about dolphin reproduction was observed in captivity, which one might agree is not necessarily normal behavior. But what we have determined is that dolphins are most likely to mate during the spring, with male-female courtship ritual playing a large part in dolphin dating.
When copulating, the male dolphin nudges the female from behind with his sex organ for several minutes, and then mounts her from behind. After this, despite rumors about prehensile penises and other frightening-yet-fascinating misconceptions, dolphin mating is roughly as ordinary as any other mammalian mating.
Dolphins are among the most sexual of animals, and are not monogamous. When aroused, a dolphin male may mate several times an hour, often with the same female but not always. But even though the male may play and then swim away, female dolphins can usually depend on their pods to help protect the baby dolphin.