Just a quick reminder for all of those who scan OB (or any specialty) to be aware of the ALARA principle and use of the thermal and mechanical index. I was always under the assumption that the manufacturer set the limits that were safe and I didn't need to worry about it. That is absolutely not true. As sonographers, it is our responsibility to be familiar with our systems and know where the TI and MI are located on the ultrasound screen. You must be able to decrease the output power to follow the guidelines for the safe use of ultrasound in medicine. Play around with different settings and notice the change in the TI. Just applying the zoom function will increase the TI. Then, once in zoom, apply CPA, PW Doppler, or color Doppler and, again, see the jump in the TI. I will attach an article that sets limits and exposure guidelines for the safe use of ultrasound. There was also a recent Webinar "Bioeffects of Ultrasound: Reviewing Our Knowledge and Perspective." that is archived and available on the  AIUM website. The post test provides free CME for AIUM members. Happy and safe scanning!!!