Thanks for asking at Healthcare Magic. I read your question and I understand your concern. Biochemical Pregnancy is the phase from conception till implantation of embryo until detected by Ultrasound or clinically by mother then it is called clinical pregnancy. If lady is tested during this period for Beta HCG in urine or blood it will be positive but there will be no evidence on ultrasound. Most of the time it happens that female gets pregnant but then they abort for many reasons and that is manifested by heavy periods. In patients on infertility treatment, they are frequently monitored for pregnancy. They turned out to be positive for pregnancy although they have aborted the fetus, because Beta HCG remain there Untill completely metabolized from body. Needs workup for miscarriages if it s recurrent. Hope it helps best. Take your best care. Don t forget to rate this answer and close the discussion at Healthcare Magic. Regards Dr Ejaz