I was weighed at the first antenatal appointment, and they said they wouldn't be doing it again as it is against there policy. Thats because it has no real relevance, apparently. You could put on 30kg with a pg, but have a small baby and viceversa. Measuring the uterus is a much more accurate indication of baby growing. That said, I weigh myself almost every day at home because I'm worried about putting on more or less than the recommended gain