♀️Why does a woman’s fertility decline with age?
The ovaries are the most important organ in determining a woman’s fertility. The decline in fertility with age is mainly due to diminished ovarian function. Ovarian aging is reflected in two main aspects:
1️⃣ Reduction in the number of eggs
A woman’s ovaries begin to decline from birth. At birth, there are about 1 million eggs. From the first period to menopause, fewer than 500 eggs are actually ovulated. Studies show that around ages 35–36, the decline becomes rapid and ovarian reserves are nearly depleted by menopause.
We cannot observe our ovarian function with the naked eye or based on experience. Ovarian health is not only related to fertility but is also a major factor in female aging!
2️⃣ Decline in egg quality
“A woman’s age equals her egg’s age” — Egg aging becomes the primary issue affecting quality.
In obstetrics, women over age 34 are considered advanced maternal age, and comprehensive amniocentesis chromosome testing is recommended.
Research on embryo development shows that women over age 40 have a higher rate of chromosomal division abnormalities in embryos compared to younger women.
Culturing embryos to the blastocyst stage also shows a higher rate of developmental arrest in embryos from older women.
Other age-related factors that affect pregnancy include:
1️⃣ Increased chance of reproductive organ abnormalities
2️⃣ Higher miscarriage rates
3️⃣ Deterioration in physiological conditions
How should pregnancy be planned?
Clinical data and ovarian studies both clearly show that after ages 35–36, fertility and ovarian reserve begin to sharply decline, and miscarriage rates increase rapidly. The changes become even more significant after age 40.
Therefore, for women planning to have children after age 35, it is best to complete egg freezing before age 35 to preserve youthful fertility and increase future pregnancy success rates.
Regarding male fertility, the highest conception rate is before age 35. After age 50, fertility declines significantly, though the change is less dramatic than in women. As men age, sperm motility and morphology decline, but sperm concentration is less affected.
In conclusion, it is recommended that women of marriageable age, whether planning to have children or not, get a blood test to check AMH, which is an important tool for understanding ovarian function! (Not all women start with 1 million eggs at birth and reduce at the same pace!)
This test does not require fasting, and it is not affected by pregnancy, menstruation, or hormone levels. You can check your egg reserve any time, and it is a crucial indicator of fertility that every woman should know and test regularly!
