I have gone through the query and understood your concern. Hypoplasia
of the endometrium means thin endometrium
and this is usually seen with deficiency of hormone production, especially estrogen. Thick endometrium, on the other hand, is observed with estrogen excess as is seen in PCOD. Siphene is a medication given to correct high Prolactin
levels. This may have caused a breakthrough bleeding
in the mid-cycle. Please provide me the details of her investigations so I can suggest further. There should be no reason to worry since the uterus is responding to hormone treatment. Hope this helps.