I had an u/s on 7/23/13, the sonographer said i was 10w+2d with a edd of 2/16/14. when would i have conceived? when would my lmp have started?

YOU WOULD KNOW...: Those answers, not the sonographer. That person is guessing based on the results of a test, but you should really know the date of your LMP and potential conception.

See answer details: 10.2wks = menstrual weeks (i.e., # wks from lmp.) LMP should have started 10.2 wk prior to when the sono was done. Conception depends on cycle length. If you have a 28 day cycle, you conceived approx 14 days after beginning of lmp. If your cycle is longer than 28d, add the # of days in excess of 28d to the time from beginning of LMP to conception day.