With my last pg, I had 7 (6, 7.5, 9.5, 13, 14, 19, 23), 3 by obgyn who's mach is no-where near as powerful as the hospital & sonographer's machines. My obgyn, whom my GP recommended as highly experienced & 1st on her list, said the only thing they have found with lots & lots of u/sounds is a possible 1-3% decrease in birth weight. With this one, I've had 2 & next one is in 2.5wks. I had the NT scan on both occasions, as the older u get the higher the downs & trisomy risk. I'm glad I did coz my stats after U/S were extremely low compared to a higher risk b4 hand (results in www - milestones). I also used my doppler 1-4 times/mth, which is much lower in power/strength again.