If indicated, we will perform a sonogram to determine the length of your pregnancy. A sonogram is a test which uses sound waves to see the pelvic structures. It is not an X-ray and there is no radiation. A sonogram is done while you lie down and a gel solution is applied to your abdomen. There is little or no discomfort while the sonogram is being performed.
A sonogram is considered the most reliable method of assessing the length of pregnancy.
The length of pregnancy is based from your last menstrual period and not from the date of conception. Therefore, if you think you conceived 8 weeks ago, your last menstrual period was probably 10 weeks ago and you would be considered 10 weeks pregnant.