Breach of Mars (Primogenitor Series, #2)

Two years after colonists settle on Mars, not a single pregnancy has made it to term. Loss piles upon loss, and when yet another ends without explanation, the underlying cause must be found. As leader of the Martian Reproductive Council, Theresa and her team of experts will determine the future of Mars. Amidst conspiracies and restrictive deadlines, they must find a viable solution - or choose between being the first and last generation of Martians, and returning to Earth.