When Your Cycle Speaks: Understanding PCOS, Endometriosis, Adenomyosis, and Hormonal Imbalance

Dorcas Akobundu
Jul 14
3 min read

For many people, the menstrual cycle is seen as a monthly inconvenience.

Something to endure and move past. But medically, the menstrual cycle is far more than that. It is a finely regulated hormonal system, and when something goes wrong, the cycle is often the first place the body shows it.

Conditions like polycystic ovary syndrome (PCOS), endometriosis, adenomyosis, and broader hormonal imbalances may appear different on the surface, but they are all deeply connected through one central system: the menstrual cycle.

Understanding that connection is key to recognizing when something is not normal.

The Menstrual Cycle

A normal menstrual cycle is controlled by a coordinated interaction between the brain, ovaries, and uterus. Hormones such as estrogen, progesterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) regulate the cycle in phases, preparing the body for ovulation and possible pregnancy.

There are four phases, namely:

Menstruation (shedding of the uterine lining)
Follicular phase (follicle maturation)
Ovulation (egg release), and
Luteal phase (preparation for possible pregnancy)

When balance is maintained, cycles tend to be regular, predictable, and relatively symptom-free. But when the hormonal system becomes disrupted, the effects can show up as irregular periods, intense pain, abnormal heavy bleeding, or even infertility.

When the Cycle Is Disrupted

A) Polycystic Ovary Syndrome (PCOS)

PCOS is primarily a hormonal and metabolic disorder affecting ovulation. Instead of a regular release of an egg, ovulation may be delayed or absent. This leads to irregular or missed periods.

PCOS is often associated with:

Elevated androgen (male hormone) levels
Insulin resistance
Irregular menstrual cycles

PCOS mainly disrupts the timing and regularity of the menstrual cycle.

B) Endometriosis

Endometriosis occurs when tissue similar to the uterine lining grows outside the uterus—on the ovaries, fallopian tubes, or other pelvic structures. These tissues still respond to hormonal changes during the menstrual cycle, meaning they thicken and bleed each month, but without a way to exit the body.

This leads to:

Severe menstrual pain
Chronic pelvic inflammation
Scar tissue formation
Possible infertility

Endometriosis is strongly linked to estrogen and inflammation, making it a hormone-dependent condition.

C) Adenomyosis

Adenomyosis occurs when endometrial tissue grows into the muscular wall of the uterus (myometrium). Unlike endometriosis, the tissue remains within the uterus but disrupts its structure and function.

This can cause:

Heavy or prolonged menstrual bleeding
Severe cramping
Enlarged, tender uterus

Like endometriosis, adenomyosis is also estrogen-driven and hormone-dependent, often involving imbalance between estrogen and progesterone.

D) Hormonal Imbalance: The Underlying Link

Hormonal imbalance is not a single disease but a broader disruption that can influence or worsen multiple conditions.

Examples include:

Estrogen dominance
Low progesterone levels
Thyroid dysfunction
Insulin resistance

These imbalances can affect: Ovulation, Endometrial growth, Pain sensitivity, and Cycle regularity.

What Do These Conditions Have in Common?

Although they are different diagnoses, these conditions share important features:

They are hormone-dependent, especially involving estrogen.
They are influenced by the menstrual cycle phases.
They often involve inflammation and immune dysfunction.
They can significantly impact fertility and quality of life.

Endometriosis and adenomyosis, for example, share similar mechanisms involving abnormal tissue growth, inflammation, and hormonal dysregulation.

Why Are They Often Confused?

One of the biggest challenges in women’s health is that these conditions look very similar clinically.

Common overlapping symptoms include:

Painful periods (dysmenorrhea)
Heavy menstrual bleeding
Pelvic pain
Pain during intercourse
Fatigue
Infertility

For instance, both adenomyosis and endometriosis can cause severe pain and abnormal bleeding, even though the underlying location of the disease differs.

Because of this overlap:

Many patients are misdiagnosed.
Diagnosis is often delayed,
Symptoms may be normalized as “just bad periods”.

When Should You Be Concerned?

A menstrual cycle is considered a vital sign of reproductive health. You should consider seeking medical evaluation if you experience:

Cycles shorter than 21 days or longer than 35 days.
Missed or irregular periods.
Severe pain that disrupts daily life.
Heavy bleeding (soaking pads frequently or passing large clots).
Persistent pelvic pain outside your period.
Difficulty conceiving.

Conclusion

Your menstrual cycle is more than a monthly occurrence. It is a reflection of your internal health. When it becomes irregular, painful, or overwhelming, it is not something to ignore.

Conditions like PCOS, endometriosis, adenomyosis, and hormonal imbalance may present differently, but they are all connected through the same biological system. Understanding that connection is the first step toward better awareness, earlier intervention, and improved care.

Sometimes, what feels like 'just a period' is your body trying to tell you something important.

References

Critchley, H. O. D., Maybin, J. A., Armstrong, G. M., & Williams, A. R. W. (2020). Physiology of the endometrium and regulation of menstruation. Physiological Reviews, 100(3), 1149–1179.https://doi.org/10.1152/physrev.00031.2019

Reed, B. G., & Carr, B. R. (2023). The normal menstrual cycle and the control of ovulation. In Endotext. StatPearls Publishing.https://www.ncbi.nlm.nih.gov/books/NBK279054/

World Health Organization. (2023). Endometriosis.https://www.who.int/news-room/fact-sheets/detail/endometriosis

Zondervan, K. T., Becker, C. M., & Missmer, S. A. (2020). Endometriosis. New England Journal of Medicine, 382(13), 1244–1256.https://doi.org/10.1056/NEJMra1810764

Assessed and Endorsed by the MedReport Medical Review Board