So we had our 20w US and found out it was a boy. We were hoping for a girl as my husband and his father were difficult children and did (more then most) stupid stuff that got them injured a lot. Well just after our tech said well it could be a good well behaved little boy who doesn't get hurt a lot and what does our son do??? HE STARTS KICKING HIMSELF (repeatedly) IN THE HEAD! She couldn't help but laugh. Yup we will be medical bill poor for the next 18 years, lol.