Implantation bleeding typically starts about 6 to 14 days after ovulation or fertilization. Most commonly, it occurs around 10 to 14 days after ovulation, which coincides with the time a person might expect their menstrual period. This bleeding happens when the fertilized egg attaches to the uterine lining, disrupting some small blood vessels. The bleeding is usually light, lasting from a few hours up to two or three days, and tends to be pink or light brown in color rather than the bright red associated with menstrual bleeding. It often appears as spotting rather than a full flow and should not soak through multiple pads or contain clots. Mild cramping sometimes accompanies it, but it is generally less intense than menstrual cramps. Because implantation bleeding happens close to the expected time of a period and is lighter and shorter in duration, it can easily be mistaken for a light period. If the bleeding is heavy, includes clots, or is accompanied by strong pain, it might indicate something else, and a healthcare provider should be consulted. In summary, implantation bleeding starts about 6 to 14 days after ovulation and is usually light spotting that lasts a day or two.
