LOS ANGELES (Reuters) - A Los Angeles official moved on Tuesday to crack down on so-called maternity hotels he said have sprung up across parts of Southern California as pregnant women travel to the United States in a growing "birthing tourism" trend. Los Angeles County Supervisor Don Knabe asked colleagues to approve a series of steps designed to ultimately close the hotels - typically single-family homes carved into bedrooms where visiting women pay to stay in anticipation of giving birth to a child who will be born a U.S. citizen. ...