My cycle usually comes every 28 days but in August and September it has been coming on the 21st. I still havent gotten it for this month and last month was very light... the color was lighter too. I have taken a couple of pregnancy tests and they all came out negative. Do you think I could still be pregnant?

Pregnancy tests are pretty accurate. If your cycle length has changed and the flow has become lighter you need to have your doctor check a thyroid hormone level and a prolactin level. These are two hormones that can affect your cycle's regularity and can affect ovulation. If these are normal, then you need to keep track of your cycle and if the abnormal length and flow persist, it may be a sign that you're not ovulating regularly. Failure to ovulate is fairly easy to correct but does require evaluation by a Gynecologist or Reproductive Endocrinologist.

Answered by Dr. Lynn Friedman, M.D.