Ever wonder why there are so many babies born in the fall? Seems it may have something to do with sperm performance in winter and early spring. A new study published in the American Journal of Obstetrics & Gynecology points to seasonal variations in sperm cells as a possible reason why there is a seasonal birth pattern. Based on samples from more than 6,000 men, researchers found sperm in greater quantity with faster swimming speeds (motility) and fewer abnormalities in semen made during the winter. These characteristics all decline in quality from spring onward. This pattern holds true for most of the men with normal sperm production. Those with abnormal or low sperm counts tended to produce faster sperm in fall and more normal-shaped sperm in spring. This new-found information could help with fertility issues, and help couples figure out when the best time to try to conceive is. So I guess all those autumn babies may have less to do with the fact that winter is cold and more canoodling takes place because of that, and more to do with sperm peaking during the winter months. Nevertheless I'm sure many couples would agree that baby-making is still a great activity for staying warm!