I had a difficult pregnancy that required me to be referred to a complicated OB/GYN. I got ultrasounds nearly every three weeks starting from 6 weeks. I was told (and believe) that it was safe for the baby. Thankfully, my baby was perfectly healthy and continues to be.
Additionally, my husband wanted to be surprised by the gender of our daughter, so we kept reminding the Dr., during each ultrasound, that we didn't want to know the sex. We were given three baby showers; work friends, & family. We heard countless complaints about how difficult it was to buy for our baby. Well in the end we did end up with much more practical gifts than if we'd known the sex. We didn't end up with a bunch of "pink" or "blue" stuff. We did get yellow, green, & white clothing. Also lots of bathing, diapering, non-clothing essentials and big gifts. Such as car seat, high chair, (neutral colors) and gift cards. We were also fortunate get lots of valuable advice, such as baby is going to outgrow thing very quickly, so don't open every item you recieve because you may need to exchange it for a larger size, and that we certainly did. Our daughter was born in the summer, so she wore very little newborn sizes and we exchanged things for winter clothing or feeding accessories, like microwave sterilizer. I found our family to be much more excited about the arrival of grandchild #24, than of the other babies whose sex was known before hand. Good luck on your decision.