A 1993 study suggests this type of screening may be unnecessary for low-risk pregnant women
Ultrasound Scans- Cause for Concern - Sarah Buckley  When I was pregnant with my first baby in 1990, I decided against having a scan. ... when used as a screening tool for every pregnant woman and her baby. .... In one study involving women at high risk, almost 10 percent of scans were ... mortality nor a lower rate of unnecessary interventions can be expected from routine...
Changes - The Object of History | Behind the Scenes with the ...  It tells a story of innovations in technology and manufacturing. ... In 1870, there were very few women office workers. ... In the 1880s, when the typewriter was first adopted in many offices, America was a country in the throes of ... To make the machine cheaply enough to reach a large market, it had to be mass-produced.