Why Does Menopause Happen?

by | Feb 8, 2024 | Menopause

I’m asked every day… “Dr. Hoppe, why do I have to go through menopause?”  The answer is every woman will – if she lives to the average of 51, with the range of approximately 42 – 58 years of age.  It’s a natural transition from a reproductive stage of life to a non-reproductive stage of life.

But, why does it happen at all?

Simply put, it’s because a woman’s ovaries run out of eggs.  Yes, during a woman’s reproductive life, her ovaries are releasing eggs at ovulation, which means the mid-cycle of a woman’s monthly menstrual cycle.

Do you know when in a woman’s life she has the most eggs?

It’s actually, in utero!  Yes, at approximately 20 weeks of gestation a female fetus growing in her mother’s womb/uterus will possess the most eggs in her lifetime!  Approximately, 6-7 million eggs!!  These eggs are also known as oocytes.  At birth, this number decreases to 1-2 million and at the time of puberty/first menstruation, only 300,000 to 500,000 oocytes are remaining.

How many oocytes are actually ovulated during a woman’s life?

The majority of oocytes will be lost through a process of apoptosis (normal process during growth and development) and atresia (loss of eggs due to aging process).  Only 400-500 oocytes will be ovulated during a woman’s reproductive years.

What happens during perimenopause?

As a woman ages, so do her ovaries.  This means that any environmental factor can affect her oocytes, leading to increased chromosomal damage and increased risk of miscarriage.  A perimenopausal woman can still get pregnant so birth control should be used to avoid pregnancy unless a pregnancy is desired.

What happens at menopause?

Menopause is defined as 12 consecutive months without a menstrual cycle.  This means the ovaries no longer have any viable eggs to ovulate, leading the precipitous drop in sex hormones, estrogen and progesterone, as well as testosterone.

These huge hormonal fluctuations, which occur during perimenopause and menopause, lead to many symptoms including hot flashes, night sweats, loss of libido, irritability and brain fog.