Why do some women say they've had periods during preg? is it really a period? for those who had a successful pregnant what was the cause of the bleeding?

Pregnant, bleeding : If you've a short menstrual cycle, it'll still take the fertilized egg 6-12 days to reach ;implant in the uterine lining. Until that happens the menses is likely this is due to conception that occurs close to menses.Many women mistake implantation bleeding for their period. Spotting on day 23 of your period may be implantation. Other reasons i.E cervical changes, infections, placenta problems etc.