Irregular (oligomenorrhea) or absent menstrual cycles are a hallmark feature of Polycystic Ovary Syndrome (PCOS), typically resulting from anovulation. Without ovulation, progesterone is not produced—leading to missed periods and potential downstream consequences.
Why This Needs Attention
There are two key reasons why managing amenorrhea in PCOS is essential:
🔹 Endometrial Health
Ongoing exposure to oestrogen without regular shedding of the uterine lining can lead to endometrial hyperplasia. Over time, this may progress to abnormal cellular changes and increase the risk of endometrial cancer.
🔹 Fertility Considerations
For individuals seeking pregnancy, infrequent ovulation—e.g. six periods per year—significantly reduces the chances of conception.
Restoring Cycles: Options Beyond the Pill
Lifestyle modifications and insulin-sensitising agents can help restore ovulatory cycles. However, if menstruation has been absent for three months or more, medical intervention is often required to induce a bleed.
Patients are sometimes advised that they must start the oral contraceptive pill to manage irregular cycles. While the pill is a safe and effective option—with benefits including reduced androgenic symptoms and lower risk of ovarian and endometrial cancers—it is not the only solution.
Importantly, the pill may not be appropriate for everyone:
- Those planning conception in the next 0–2 years
- Individuals with contraindications to oestrogen
- Patients without hyperandrogenism who may not benefit from its anti-androgenic effects
- Those who prefer to explore restoration of natural cycles
Alternatives for Endometrial Protection
For patients not suited to or preferring to avoid the pill, we can offer cyclical progesterone therapy (e.g. Prometrium 200mg or Provera 10mg for 12 days every 1–3 months) to induce withdrawal bleeds. This approach also serves as a diagnostic progesterone challenge to differentiate from Functional Hypothalamic Amenorrhea (FHA).
Following a bleed, an ultrasound can assess endometrial thickness. If the lining measures <7mm, we can be reassured against hyperplasia and continue with progestogen withdrawal bleeds as a protective strategy.
Considering Long-Term Management
Long-acting hormonal contraceptives such as the Mirena IUD offer excellent endometrial protection and contraception, with fewer emotional and mental health side effects than the pill. They are well tolerated and don’t require daily dosing.
While Provera may be useful diagnostically, it is not a contraceptive and carries risks in women of reproductive age not using reliable contraception. Its long-term use is generally not preferred.
This is not an “anti-pill” message—it’s a reminder that patients have options. The best approach is one that considers your individual goals, medical history, and preferences. Shared decision-making remains central to effective endocrine care.