Brief Answer:
delayed menses...explained

Detailed Answer:
Hello,
Thanks of the query to healthcare magic.com
The very fact that she had ipill on 4th day of menses was not actually required as she was already in her safe period when ovulation wouldn't have occurred. But as the ipill which is a progesterone was taken in the first few days in the follicular phase it is likely that the menses would be delayed.
If you would have been sexually active after the ipill then you must get a urine pregnancy test done to rule out pregnancy first and if negative then you can safely wait for another week for the menses to return naturally.
if it still doesn't then an ultrasound pelvis should be done to check for endometrial thickness of the uterus and if more than 10mm , a withdrawal bleeding can be opted for with progestins to resume the menses.
I hope i have answered your query in detail,
wishing you good health,
Regards

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