Thanks for the query.
After stopping the progesterone
pills, sometimes it may take around 7 weeks for onset of withdrawal bleeding.
The possible causes of delayed periods:
-Poly cystic ovary disease or other hormonal
So you consult gynecologist once, get examined, go for ultrasound
and hormonal profile to find out the possible cause for the problem and take treatment accordingly.
For more details you can ask me through: http://www.healthcaremagic.com/doctors/dr-sree-gouri-sr/63429