How many days after artificial insemination does implantation occur?

Implantation following intrauterine insemination (IUI) typically occurs between 6 and 10 days after the procedure—most commonly around day 8 or 9 post-insemination. This timing aligns with the natural window of implantation in spontaneous conception, as IUI does not alter the biological timeline of embryo development or endometrial receptivity. After ovulation (which is usually timed precisely before IUI), the fertilized egg—now a blastocyst—travels through the fallopian tube to the uterine cavity and attaches to the receptive endometrium. It’s important to note that implantation cannot occur before day 6, as the blastocyst requires sufficient time to develop and reach the uterus; similarly, implantation beyond day 10 is uncommon and may be associated with lower pregnancy viability. Clinical signs such as light spotting (“implantation bleeding”) or mild cramping are nonspecific and not reliable indicators—definitive confirmation requires a quantitative serum beta-hCG test, ideally drawn no earlier than 10–12 days after IUI.