Now in your case scenario, it might have been chemical pregnancy and very early miscarriage, knowing that miscarriage is the most common type of pregnancy loss or spontaneous abortion. It is estimated that 10-25% of all clinically recognized pregnancies will end in miscarriage. Chemical pregnancies may account for 50-75% of all miscarriages. This occurs when a pregnancy is lost shortly after implantation, so the woman gets vaginal bleeding that coincides with the time of her expected period. Chemical pregnancy may be really tricky, so you may not be aware that you have conceived.