Comprendre la périménopause : une transition hormonale

The perimenopause (or the transition to menopause) is the period during which the ovaries' hormonal function gradually changes, leading up to the final cessation of menstruation.

• It typically occurs between the ages of 40 and 50.
• It can last for several years—often 2 to 4 years, but sometimes up to 10.
• Menopause is officially reached when menstruation has ceased for 12 months.

What happens on a hormonal level?

During perimenopause and menopause, several sex hormones undergo significant changes—sometimes fluctuating, sometimes experiencing a lasting decline.

• Decrease in estrogen production (notably estradiol) : with age and declining ovarian function, estrogen production decreases. However, this decline is not linear: during perimenopause, levels can fluctuate (sometimes rising, then falling again).
• Drop in progesterone : progesterone, produced after ovulation, decreases because ovulations become less frequent. It is worth noting that the drop in progesterone often precedes the drop in estrogen, which creates the classic symptoms of early perimenopause, where menstrual cycles are often heavier and we see an exacerbation or return of PMS.
• Fluctuations in FSH and LH : the pituitary gland (in the brain) produces FSH (follicle-stimulating hormone) and LH. When ovarian production decreases, FSH (and to a lesser extent, LH) increases in response—which leads to sometimes significant hormonal variations.
• Decrease in other hormonal markers (such as anti-Müllerian hormone, AMH, or inhibin) : these hormones, produced by the ovaries, decrease with age and ovarian reserve. This contributes to the disruption of hormonal regulation.

In summary, perimenopause is often described as a period of "hormonal roller coaster" : ups and downs, sometimes significant fluctuations, before the stabilization (at a low level) of certain hormones during menopause.

Hormonal consequences: symptoms and physiological changes

These hormonal fluctuations and declines can have multiple, varied effects—sometimes subtle, sometimes pronounced—depending on the individual.

Common effects include:

• Changes to the menstrual cycle : irregular cycles, cycles that are closer together or further apart, heavier or lighter periods, or longer cycles, leading up to the permanent cessation of menstruation.
• Hot flashes and night sweats : unpredictable estrogen levels disrupt body temperature regulation, causing these "vasomotor" symptoms.
• Sleep disturbances : often caused by nighttime hot flashes, but sometimes linked to a drop in progesterone.
• Vaginal dryness and changes : as estrogen levels fall, the vaginal lining becomes thinner and less lubricated, which can lead to dryness, discomfort, pain during intercourse, or an increased risk of urinary or vaginal infections.
• Changes in libido or sexual health : decreased desire and potential sexual discomfort.
• Metabolic and bone changes : the drop in estrogen is associated with a loss of bone density (risk of osteoporosis) and sometimes changes in fat distribution—notably abdominal weight gain.
• Potential impact on mood, mental well-being, and cognition : hormonal fluctuations, sleep disturbances, and physical changes can cause irritability, mood swings, sleep issues, fatigue, "brain fog," memory lapses, mood disorders, or anxiety.

It is important to emphasize that every woman experiences this transition differently — some will have very few symptoms, while others will have many.

Why this period is crucial for your health

Perimenopause and menopause are pivotal times for your health. While hormonal shifts can increase certain risks, they also provide a valuable opportunity for preventive care. For example:

• Bone health : Lower estrogen levels accelerate bone loss, which can lead to osteoporosis and increase the risk of fractures.
• Cardiovascular and metabolic health : This period often brings changes that favor the development of metabolic syndrome (abdominal fat, insulin resistance, etc.) and less favorable lipid profiles, which can increase the risk of cardiovascular disease.
• Urogenital health : Increased risk of urinary tract infections, vaginal discomfort, and incontinence.
• Overall quality of life : Sleep disturbances, mood swings, stress, fatigue, relationship strain, and changes in general well-being can all impact your daily life.

This is why this phase deserves attention and support—it is an ideal time to consider management, prevention, and monitoring strategies (lifestyle, bone density, general health, etc.).

In summary: key takeaways

• Perimenopause is a gradual transition —not a single event—marked by significant hormonal fluctuations.
• These hormonal changes (declining estrogen and progesterone, variations in FSH/LH, and drops in other markers) have varied effects on the body —including menstruation, metabolism, bone health, sexuality, mood, sleep, skin, and more.
• Experiences vary greatly from one woman to another: some will have few or no symptoms, while others may experience several, sometimes severe, symptoms.
• This period represents a pivotal time to monitor certain aspects of your health (bones, heart, metabolism, general well-being) and consider personalized interventions or support.

📄 Downloadable document

Finding balance when your body changes
A chart of symptoms associated with progesterone and estrogen deficiency to help you better recognize the signs of perimenopause.

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Source: Prenato