Testosterone is often treated as a marker of health and vigor, especially in men. But new genetic evidence suggests it’s not all good: higher lifelong levels of the hormone may also increase the risk ...

This method is time-consuming and expensive, but it is also an incredible method to prevent conception with eggs that have evidence of genetic abnormality. A petri dish is seen following an embryo ...

November 24, 2025 • Our annual reading guide returns with 380+ new titles handpicked by NPR staff and trusted critics. Find 13 years of recommendations all in one place — that's more than 4,000 great ...