Brief Answer: DETAILED BELOW Detailed Answer: Hello Thanks for writing to us with your health concern. Normally, after taking Regestrone for withdrawal bleeding, you would bleed within 2 - 3 days, and maximum within a week. The fact that 10 days have passed means that the hormone did not work for withdrawal bleeding. I would be able to guide you better if you provide me more details - 1 . Your last menstrual period, and general pattern of menstrual cycles. 2. Reason for taking hormones for inducing withdrawal bleed. 3. Any other significant history or medical condition or diagnosis, which prompted your doctor to prescribe Regestrone, as I hope the medication was taken after consultation with a gynecologist. If you could write back with these details, I could answer you better. Speaking generally, there could be a few reasons why Regestrone did not work. Firstly, there is the possibility of a pregnancy, or a related complication like a miscarriage or an ectopic pregnancy. So please take a pregnancy test, or if you have irregular cycles, rule out pregnancy by consultation with a doctor ( ultrasound or a blood test ). Other conditions like polycystic ovaries, endometrial hyperplasia etc. also can cause delayed cycles, but in these cases, generally hormonal withdrawal with progesterone works, unless the conditions are severe. Also, stress, anxiety, weight gain, hypothyroidism - all these can cause menstrual irregularities - these too would respond favourably to progesterone withdrawal. If the uterine lining is very thin due to hormonal imbalance, infections or congenital hypoplasia of the uterus - you might not experience any result with hormone withdrawal. Please provide further more specific details so that I can guide you better. All the best. Looking forward to hearing from you soon.

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