4.1 Perimenopause

[Read time: 5 minutes]

The time leading up to menopause day (and medically defined as a year after as well) is called perimenopause. In other words, around menopause and the years leading up to Menopause Day.

The average age of a perimenopausal woman is between 40–50 years of age [1].

Perimenopause is triggered by ovarian aging, which then leads to a drop in ovarian estrogen and progesterone levels. This shift in ovarian hormones has a cumulative effect on the entire system as part of the hormone collective. The shift can then be observed as signs & symptoms, which may be physical, psychological or physiological. Some people may find the changes collectively have a high negative impact on their well-being. Some will find the impact is moderate, and some slight.

From mid to late perimenopause periods often move to an irregular pattern when ‘fertility can no longer be predicted’. Ovarian hormone levels are fluctuating unpredictably. A bit like puberty in reverse.

It is the unpredictable changes in ovarian hormones that contribute to the symptom trigger, not only the level itself. Postmenopause, when the menstrual cycle ovarian activity has stopped many aspects of perimenopause symptomology reduce significantly and many disappear altogether, and some functionality is reimagined to a whole new level.

Remember, this is a part of the menstrual health continuum and is not optional, but how you choose to manage the process is. Plus, how the transition is approached is hugely significant to long-term health outcomes.

The Operating System (OS) Changes

When periods start the years of initial glitchy irregularity eventually give way to a regular pattern. Overall levels of sex hormones rise until the late 20s. Think of this as Operating System (OS) 1.0

OS 2.0 is from the late 20s to late 30s when overall levels plateau. 

From the tipping point, around age 37 (+/-2yrs), when the ovarian reserve has reached a threshold of 25,000 follicles remaining, ovarian aging starts to accelerate and we observe an initial, subtle, process of hormonal decline [2]. A couple of years later the transition into operating system 3.0 begins, which turns out to be very similar to OS1.0, in terms of glitchy patterns.

OS 3.0 has many variants over time with regular incremental updates. One day you may be in version 3.01 and the next day 3.41. If too many tabs are left open at any one time or an update is missed, the system can be overwhelmed and will need to recalibrate at regular intervals. However, when all the factors are considered the capabilities and functioning of this Operating System are certainly effective and worth adapting to.

Finally, the ultimate OS4.0 is the reconditioned, debugged, fast operating, multitalented version of OS2.0, with so many additional features that can be explored and added on when required.


Whilst hormonal decline appears to start earlier than you would imagine the initial signs and indicators of perimenopause may be very intermittent, hence why menstrual health tracking will come in useful at this point to observe change.

One particular shift that is characteristic of nearly all transitions is the increase in the anovulatory cycles (no egg release), which creates a different kind of bleed. Sometimes heavy and long and sometimes light and short [3] In addition, there can be a temporary pause of the cycle, and then restarting again. This creates huge changes in the Estradiol: Progesterone ratio, which has a knock-on effect on how the hormone collective is being conducted, and reacting to the shift.

Oestrogen as the master regulator is taking a break, quite literally, and the orchestra is wandering around doing its own thing [4]. As such, the hormone collective in general needs to be supported at all costs with effective management of cofactors. The ovaries cannot be controlled but can be influenced by the cofactors.

Early indicators are mostly related to brain health and include:

(NB. The words ‘out of character, ‘sudden’ and ‘strange’ should really precursor all indicators.)

  • sadness (often described as depression-like)*
  • anxiety
  • panic
  • mood changes
  • loss of confidence
  • a disconnect with yourself and those around you (women of prayer find this incredibly difficult to manage alongside their spirituality)

* Data shows that people who have experienced depression of any kind, including post-natal depression in the past, are more likely to have a recurrence during perimenopause [5]

The early indicators are generally transient and not there all the time, which is again why journalling is really helpful to add context, plus provides data for a health care practitioner to discuss options and highlight if symptomology is NOT related to the ovarian activity.

Menstruators can find this time very upsetting and the phrase ‘I feel like I am going mad’, is commonly heard.

How do you know if it’s perimenopause?

If you don’t know what a perimenopause symptom is, how do you know if you have had one? Tuning into the mind and body as soon as possible along the journey will help menstruators learn how they individually respond to hormone shifts, so when change happens you can spot it and decide what steps to take.

Other health conditions may be present and certainly need to be paid attention to, but even so, the menstrual health timeline is proceeding, so conditions need to be considered ‘as well as’, not ‘instead of’ perimenopause. Using a journal will help join the dots between all the changes occurring, and will support decision-making with a healthcare professional.

Early signs of perimenopause are reported by women in their early 40s and are often not connected to hormonal decline, causing a misdirection in a chosen path of treatment (medical or complementary) or lifestyle changes. This is a missed opportunity to make adjustments to the cofactors and support the menstrual health journey with a whole-person approach.

The day periods start to the day they stop, you are menopausing to a greater or lesser extent.

Fiona Catchpowle, The Menopause School

In conclusion:

Lack of knowledge of the process and confusion overload will delay perimenopause being noted as the underlying cause of an indicator and ongoing symptom.

Teaching menstruators, of all ages, how to effectively manage their menstrual health, will facilitate quicker response times by the individual to modify the cofactors that work best for them.

NB. Operating System 4.0 is worth the wait!