The process, which would carry significant safety concerns, involves removing the nucleus from a woman's skin cell and inserting it into an egg, or oocyte.

It is no longer science fiction: human embryos have now been made from DNA in skin cells that were fertilised with sperm, a move that redrafts the biological limits of reproduction. At an Oregon ...

There are many potential causes of infertility, and it can be challenging to pin down just what the problem is when a couple is having trouble getting pregnant. Now, researchers show that a few key ...

LONDON -- British scientists claimed Wednesday to have created human sperm from embryonic stem cells for the first time, an accomplishment they say may someday help infertile men father children. The ...

Human fertility hinges on a delicate molecular ballet that begins even before birth. UC Davis researchers have uncovered how special protein networks safeguard chromosomes as eggs and sperm form, ...

The embryos weren’t used to try to establish a pregnancy, but the researchers behind the technique say it could one day be ...

In a scientific breakthrough that raises a number of medical and ethical issues, researchers have used stem cells to create living, growing models of a human embryo. Because stem cells were used, ...

Almost every type of human cell is powered by mitochondria, bean-shaped organelles that use oxygen to synthesize usable energy.* These structures evolved billions of years ago from free-swimming ...