This scan may take a bit longer, however, as the sonographer will have a really detailed look at the development of your baby, and the health and position of your placenta. (mumsnet.com)
Your doctor will use a thin catheter through your cervix or a needle through your abdomen to collect the cells, depending on the position of your placenta. (alphamom.com)
Doctors usually monitor the health of the placenta on their own as well and use ultrasounds to make sure that there are no issues with the size and position of the placenta. (newhealthadvisor.com)