You're born with all the eggs you'll ever have in your life, about 1 million. By the time you hit puberty, you may have about 300,000 left. At 37, you're down to just 25,000 -- or 2.5% of your starting count. That matters because the fewer eggs in your ovaries, the lower your odds for conception.
They will have around 120,000 eggs, with a 20% chance of conceiving per cycle. ACOG further states that a female will experience a rapid decline by age 37, when egg count drops to around 25,000.
This proportion rises to ~50% by age 37-38 and to over 70% at age 40 and beyond.
At 37-38 years, even healthy women will have around 25,000 of their eggs but by then the quality of these eggs also becomes a concern.
For example, a woman at 30 often has around 100,000-150,000 eggs in reserve. By 35, that number is likely around 80,000. Late into the thirties, that number could be 25,000, 10,000, or fewer.
Even though women start with 1–2 million eggs, by the time you reach puberty only about 300,000–400,000 of the eggs you were born with remain. The monthly cycle described above then continues throughout a woman's life until there are no eggs left.
There are two good ways to measure egg count: an antral follicle count and an AMH (anti-Müllerian hormone) test. During an antral follicle count, a doctor uses ultrasound to count the visible follicles. Each follicle contains an immature egg that could potentially mature and ovulate.
Egg Quality Deteriorates With Age
Your age affects the health of your eggs. Women reach the peak of their fertility at around age 24. After this age, egg quality slowly deteriorates until around age 37, and then deteriorates more rapidly until about age 42.
Can I get pregnant if I'm older than 35 or 40? Yes, you can, but you may find it takes a bit longer to get pregnant than a woman in her 20s. Every woman is born with a set number of eggs in her ovaries, and you release an egg every menstrual cycle.
Women lose 90 per cent of the eggs in their ovaries before the age of 30, new research has shown.
You're born with all the eggs you'll ever have in your life, about 1 million. By the time you hit puberty, you may have about 300,000 left. At 37, you're down to just 25,000 -- or 2.5% of your starting count. That matters because the fewer eggs in your ovaries, the lower your odds for conception.
When the woman is over 37 years old, reduced egg quality is often a contributing factor, when it is difficult to become pregnant. Therefore, it is likely that for some couples infertility is solely due to the quality of the woman's egg.
At around age 37, fertility starts to decline at a much more rapid pace. Research has found that in any given month your chances of getting pregnant at age 30 are about 20%. Compare that to your odds at age 40, which are just 5%.
Once she starts her periods, 1 egg develops and is released during each menstrual cycle. Pregnancy happens if a man's sperm meet and fertilise the egg. Sperm can survive in the fallopian tubes for up to 7 days after sex. Occasionally, more than 1 egg is released during ovulation.
If you're under 35 and in good health, it's perfectly natural for it to take up to a year. It can take longer if you are older, however; for women aged 38, 67% who have regular unprotected sexual intercourse will only get pregnant after two years of trying2.
Despite the obstacles, rest assured that women in their 30s and 40s can conceive and go on to have successful pregnancies. A natural age-related decline in fertility is due to fewer eggs, less frequent ovulation and poorer egg quality. As you age, you may be less likely to release an egg during every cycle.
It can take longer if you are older, however, for women aged 38, 67% who have regular unprotected sexual intercourse will still get pregnant after two years of trying2.
For example, if you are 37 years old, you should freeze at least 10 eggs in order to attain the highest chance of having a child. If you are 38 years old, you should aim to freeze 16 eggs to reach the same chance of having a baby.
Egg freezing typically works best for those in their 20s to early 30s, and is not usually recommended for women over 38 years.
Egg quality starts to decline at age 32 and decreases rapidly after 37. Advanced maternal age also heightens the risk of birth defects. Only 28 percent of women, and 35 percent of men, believe age is the number one contributor to female infertility, the AOA survey found.
However, the belief that the follicles are empty is under debate. The incidence of this syndrome has been estimated at 0.6–7.0%.
How many eggs does a woman have at 40? By the time a woman reaches 40, she'll be down to about 18,000 (3% of her pre-birth egg supply).
After starting the menstrual cycle, a person loses about 1,000 immature eggs every month, according to Dr. Sherman Silber, who authored “Beating Your Biological Clock,” a guide for his patients who have trouble with fertility.