Sperm, the millions of swimmers carrying one-half of the reproductive power, is deposited into the vagina in semen. Semen was once thought to be the mode of delivery and lubricator, making it easierfor sperm on the long trek to find the egg. Researchers from the University of Saskatchewan in Canada think semen is due a little more credit than that. There is reason to believe semen contains a secret ingredient that promotes ovulation so the female body knows it’s time to get pregnant. The presence of such an ingredient could play an extremely important part in fertility science and medicine with drastic changes made to fertility treatments to improve outcome.

In order to better understand the revelation, researchers explain there are two types of animal ovulation – spontaneous and induced. Spontaneous ovulation occurs in most animals and humans. Ovulation occurs whether or not sex is occurring. Induced ovulation, found in rabbits, camels and afew other animals, means eggs are released during sex – no matter how often sex occurs. There is no definitive pattern and if a female rabbit is housed alone for life, she will never ovulate.

The special ingredient researchers are so excited about has been termed OIF or ovulation-inducing factor. This is not the first time OIF has been described. In 1985, another team of researchers recognized OIF when female llamas were injected with semen taken from male llamas. When the semen was injected, the females ovulated – without sex or stimulation of any kind. Llamas are much like camels in that they ovulate in response to sex. With extensive research and pain-staking hours in the lab, researchers were able to narrow down a single element in llama semen that induced ovulation – neural growth factor or NGF. When the NGF protein was injected by itself, ovulation occurred. The mystery secret ingredient turned out to be a common part of semen across many species.

Researchers know NGF moves into the bloodstream where it heads to the brain. It sparks action from the pituitary gland and hypothalamus. They release hormones needed for pregnancy and the process begins. Fertility specialists are extremely excited about the discovery. NGF is the spark that starts pregnancy, but with knowledge comes questions. Could infertility be caused by lack of response to NGF? How does NGF work in the hypothalamus and pituitary gland? This is just the first step in what looks to be a huge advancement in fertility and pregnancy science.