Brief Answer:
Can be due to hormonal changes.

Detailed Answer:
Hello,
Thanks for trusting us with your health concern.
The reasons of decreased or no bleeding may be hormonal imbalance, emotional upset, anxiety, stress, or other medical conditions that affect the ovaries, uterus, hypothalamus, or pituitary gland. Hypothyroidism, post pill amennorhea , polycystic ovarian syndrome or less frequently a pituitary tumor causing high prolactin levels or a hypothalamic disease are other causes that may be the cause after ruling out pregnancy.
Please visit your gynecologist to undergo physical check up and also to undergo relevant investigations required in your case to find out the cause so that treatment can be given accordingly.

Please feel free to discuss further. I will be glad to answer the follow up queries that you have.
Wishing you good health.
Regards.
Dr. Rakhi Tayal.
For future query, you can directly approach me through my profile URL http://bit.ly/Dr-Rakhi-Tayal

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Brief Answer:
Prolactin can be tested by a blood test.

Detailed Answer:
Hello.
Thanks for writing again.
Can be due to high prolactin levels or an ovarian cyst. An ultrasound scan of abdomen and few more blood tests are needed to find out the cause.
Hope my answer is helpful.
Do accept my answer in case there are no further queries.
Regards.

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