15 doctors weighed in:

What could cause an irregular monthly period? Thanks

15 doctors weighed in
Brittany Chan
Pediatrics
8 doctors agree

In brief: Many things.

Not ovulating during every cycle can cause irregular periods.
This is is common in teens as their systems mature, but may also occur in adults. Excessive exercise, stress & eating disorders can also throw periods off, as well as polycystic ovarian syndrome, ovarian or adrenal tumors, thyroid dysfunction, or too much prolactin. Spotting between periods is commonly caused by infection.

In brief: Many things.

Not ovulating during every cycle can cause irregular periods.
This is is common in teens as their systems mature, but may also occur in adults. Excessive exercise, stress & eating disorders can also throw periods off, as well as polycystic ovarian syndrome, ovarian or adrenal tumors, thyroid dysfunction, or too much prolactin. Spotting between periods is commonly caused by infection.
Brittany Chan
Brittany Chan
Answer assisted by Brittany Chan, Medical Student
Thank
Dr. Deborah Smith
Fertility Medicine
7 doctors agree

In brief: It varies

Many things can cause irregular menses such as excessive exercise, stress, eating disorders and hormone imbalances.
The most common hormone imbalance is polycystic ovarian syndrome, but ovarian or adrenal tumors, thyroid dysfunction, or too much prolactin can also cause irregular periods.

In brief: It varies

Many things can cause irregular menses such as excessive exercise, stress, eating disorders and hormone imbalances.
The most common hormone imbalance is polycystic ovarian syndrome, but ovarian or adrenal tumors, thyroid dysfunction, or too much prolactin can also cause irregular periods.
Dr. Deborah Smith
Dr. Deborah Smith
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Dr. Shelley Ham
Psychiatry
1 doctor agrees

In brief: Medications

I see this frequently amongst patients taking antidepressant and antipsychotic medications due to the effect on Dopamine and prolactin.

In brief: Medications

I see this frequently amongst patients taking antidepressant and antipsychotic medications due to the effect on Dopamine and prolactin.
Dr. Shelley Ham
Dr. Shelley Ham
Thank
1 comment
Dr. Scott Roseff
The most common cause is PCOS. Other causes can include thyroid dysfunction and obesity. See a board certified RE to find out WHY there are irregular periods so it can be best treated!
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Dr. Adam Levy
Board Certified, Obstetrics & Gynecology
33 years in practice
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