YES!!!!!!!!! There are documented cases of women spotting or having their periods during their entire pregnancy. Personally my cousin's wife was having irregular periods of length and duration. She was almost 6 months when she finally went to her Dr and pregnancy was confirmed. I knew I was pregnant and started spotting intermittently, my placenta had started to Abrupt(pull away from the wall).
If you have concerns about being pregnant and/or spotting see your Dr. DO NOT WAIT!
at 12:18 PM on Nov. 4, 2010