Serena Williams, currently ranked the NO. 9 tennis player in the world, has always been candid about her journey being a first-time mom with husband, Alexis Ohanian. The tennis star vulnerably discussed details of her difficult birth back in 2017. The pregnancy went well, but Serena's heart rate dove dangerously low during contractions leading the doctors to perform an emergency C-section. The surgery itself was without complications, but the next day became a nightmare when she felt short of breath.