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What is Uterus is receptive for implantation for how many days after feilization - and explain in detail?
Superfetation is the feilization of two ova released in two different menstrual cycles. The nidation and development of one fetus over another fetus is theoretically possible until the decidual space is obliterated by 12 weeks of pregnancy. Ref : Dutta book of obstetrics 8th Ed