Hi, thanks for using health care magic
Oligomenorrhoea is the medical term for delayed period of at least 35 days.
The possible causes include:(1) psychological and physical stress (2) abnormal levels of steroid hormone
(3) polycystic ovarian syndrome
which is a condition that consists of elevated levels of male hormone (symptoms such as acne or hirsuitism), delayed periods, cysts in the ovaries (4) abnormal levels of other hormones such as prolactin
(5) poor diet
Your doctor may suggest blood tests and imaging such as an ultrasound
to determine the exact cause of your symptoms.
I hope this helps