2 doctors weighed in:
What causes irregular periods?
2 doctors weighed in

Dr. Brian Nguyen
Obstetrics & Gynecology
In brief: Hormonal imbalance
Irregular periods are caused when your body's signals for ovulation and menstruation get confused by hormonal imbalances that can be related to your thyroid (TSH), pituitary (LH/FSH/prolactin), ovaries (estrogen/progesterone).
Many external factors can affect the hormones: malnutrition, stress, obesity, for example. Hormonal contraception can help to regulate your periods, which is healthier.

In brief: Hormonal imbalance
Irregular periods are caused when your body's signals for ovulation and menstruation get confused by hormonal imbalances that can be related to your thyroid (TSH), pituitary (LH/FSH/prolactin), ovaries (estrogen/progesterone).
Many external factors can affect the hormones: malnutrition, stress, obesity, for example. Hormonal contraception can help to regulate your periods, which is healthier.
Dr. Brian Nguyen
Dr. Brian Nguyen
Thank
Dr. Gerard Honore
Fertility Medicine
In brief: Irregular ovulation
Ovulation is necessary to have normal spontaneous menstrual periods.
After ovulation the hormone Progesterone rises; if no pregnancy occurs, Progesterone falls and a period begins. In anovulation there is no Progesterone rise: menstruation cannot occur, so periods are irregular or absent altogether.

In brief: Irregular ovulation
Ovulation is necessary to have normal spontaneous menstrual periods.
After ovulation the hormone Progesterone rises; if no pregnancy occurs, Progesterone falls and a period begins. In anovulation there is no Progesterone rise: menstruation cannot occur, so periods are irregular or absent altogether.
Dr. Gerard Honore
Dr. Gerard Honore
Thank
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