Scientists track the movement of sperm flagella.

Videos reveal how a female squid fertilizes her eggs—one at a time and without spilling much stored sperm.

For flycatchers, the attractiveness of male birds is tied to the length of their sperm.

The artificially motorized cells may one day help fight cancers in the female reproductive tract.

A project aims to preserve samples of the climate change–vulnerable animals for future restoration.

Mary Hagedorn is racing to save Earth’s coral reefs by developing techniques for freezing the colonial animals’ gametes.

New technologies reveal the dynamic changes in mouse and human embryos during the first week after fertilization.

The switch from maternal factors involves dynamic reprogramming of the zygotic genome.

Among their many functions, macrophages in mouse testes guard sperm against attacks by other immune cells.