Treating Infertility: Making Babies

More than a million couples seek treatment for infertility each year. Now some remarkable insights into the mating dance of sperm and egg are bringing answers to their prayers.

Couched in a halo of nutrient cells, an egg smaller than the dot on an i drifts slowly down a Fallopian tube, one of a pair of narrow passages that lead from a woman's ovaries to her womb. Like a beacon guiding ships at night, the egg sends forth a calling signal. A convoy of sperm -- the remnants of an armada that was once a couple of hundred million strong -- sails into view, their long tails thrashing vigorously. Lured by the chemical signal, several hundred of the most energetic swimmers close in on the egg, their narrow tips unleashing...

Want the full story?

Subscribe Now


Learn more about the benefits of being a TIME subscriber

If you are already a subscriber sign up — registration is free!