From the moment of conception, every human embryo embarks on an incredible nine-month journey of development. Now, cutting-edge technology makes it possible for National Geographic Channel's "In the womb" to open a window into the hidden world of the fetus and explore each trimester in amazing new detail. Revolutionary 3-D and 4-D imagery sheds light on the delicate, dark world of a fetus as never before and follows a rare fetoscope operation, performed in utero with the hope of correcting life-threatening complications before birth.