Suze Lopez holds her baby boy on her lap and marvels at the remarkable way he came into the world. Before little Ryu was born, he developed outside his mom’s womb, hidden by a basketball-sized ovarian cyst — a dangerous situation so rare that his doctors plan to write about the case for a medical journal. Just 1 in 30,000 pregnancies occur in the abdomen instead of the uterus, and those that make it to full term “are essentially unheard of — far, far less than 1 in a million,” said a...