Commonly, it requires quite a few weeks to the placenta cells to produce enough amounts of the hormone human chorionic gonadotropin (hCG), which can be detected through a blood test. It is actually encouraged for patients to chorus from having a pregnancy test instantly immediately after embryo transfer. According to https://www.digitaljournal.com/pr/news/insights-news-wire/ivf-mexico-best-fertility-clinic-1465491918.html