Beyoncé rocked the world–again–with news that she is pregnant with twins. But the joyous occasion raises a question whether the singer opted for in vitro fertilization to create designer babies. The practice is frowned upon by the medical profession. Celebrities have been known to use in vitro fertilization (IVF) to work in pregnancies around their busy schedules. In some cases, however, celebrities have used the process to pick the sex of their children or in many cases to have twins.