I had sex on the 29th of September with guy A I'm unsure if it were inplantation bleeding or a period which was on the 7th of Oct After my period or inplantation I had sex with guy B multiple time My due date is July 15. Have they given me this due date because I told them my period was on the 7th so they go by that? Or does the sonogropher simply go by the measurements of the baby? At my earliest scan I was 9w 5d