I have been on a generic of Loestrin FE birth control for approximately 6 years. The entire time I've been on it, I have had barely any bleeding - not enough to require the use of feminine products. On Monday of this week, I started a textbook period, which has continued through today. I am 37 years old. I have recently entered into a romantic relationship and have been having sex regularly. I cannot be pregnant, my partner is sterile. Any idea why I would suddenly start having a period? Naturally, this is an inconvenient time.