For most of history parents have wanted sons, but in recent years mums and dads in the rich world have shown an emerging preference for girls. Why is this, and what happens if they start to use technology to act on this? Video supported by @mishcondereya 00:00 - Are baby boys going out of fashion? 00:26 - Why are more boys born than girls? 01:03 - How many “missing” girls are there? 02:17 - Why do parents want baby girls? 02:58 - Are people choosing their baby’s sex? 03:39 - What are these