It is no shocker, that all things eventually come to an end, especially those that are concerned with life. That’s just how it has always been since the beginning of time. The same trend follows for fertility as well. Male and female fertility have always shown a declining graph with age, but the decline is much more apparent and consequential in women. In recent years, more and more people are becoming aware of the possible repercussions of delaying pregnancy which is leading them to consider fertility preservation options like egg freezing or other treatment options like using donor eggs.
The International Committee Monitoring Assisted Reproductive Technologies defines the term fertility as the ‘capacity to establish a clinical pregnancy. The ability to conceive or ‘establish pregnancy’ depends on several factors that could be genetic, dependent on the environment, etc. However, one of the most influential factors is age.
According to the American Society for Reproductive Medicine or the ASRM,
- On average, women under 30 have a 25% chance of getting pregnant naturally with each menstrual cycle.
- For women over the age of 30, the chances drop to around 20%.
- By 40, the chance of getting pregnant naturally each month is just 5%.
Fig. 1: Chances of Conceiving with Age
Causes of decline in the chance of conceiving with aging women
- The most eggs a woman can ever have is when she is 20 weeks old (or 5 months old) and in her mother’s womb. At this point in time, she has about 6-8 million eggs, and after this, the number only reduces.
- The reduction happens because the eggs in the ovaries constantly die in a process called ‘atresia’ and are reabsorbed by the body.
- At birth, she will have around 1-2 million eggs in total.
- From birth, till the age of puberty, which can happen anywhere between 10-15 years, she is not ovulating. But the number of eggs is consistently reduced through atresia. And this number is quite high! It has been estimated that a prepubescent girl loses almost 10,000-11,000 eggs every month!
- So by the time she reaches puberty, a girl only has about 300,000 to 400,000 eggs left in her ovaries.
- The best chance a woman has, of conceiving a healthy baby is in her 20s because of the optimal body conditions, which include sufficient reserves of good quality eggs in the ovaries, during those years.
- At 30, a woman usually has around 100,000-150,000 eggs left in her reserve. This is about 12% of her initial reserve. By 35, that number is most likely to reduce to around 80,000. A rapid decline is often seen in the number of eggs after the age of 37. The number could come down to almost 25,000 or 10,000 or even less.
- At 40, on average, the ovaries hold only about 5-10,000 eggs, which is just about 3% of her initial egg reserves.
- By the age of 50, there are only around a couple of hundred eggs left, before menopause hits.
Fig. 2: Egg Count Through the Years
Does fertility decrease in men over time as well?
In women, there is no regeneration of eggs throughout their lifetime whereas men can produce almost 100 million sperm every day. But despite the popular belief that age does not decrease fertility in men, studies have found that this is not always the case. Certain characteristics like sperm mobility have shown a decreasing trend as the years go by, but, others like sperm concentration may or may not be affected.
Erectile dysfunction or the inability to ejaculate has also been observed in many cases as men age. A lot of the older males also show the presence of fragmented or broken down DNA in their sperm cells which decreases their probability of conceiving naturally, when compared to men of younger age.
Thus, age is one of those factors which can’t be helped after a certain stage. One of the only solutions to being able to conceive a child in the later years is through egg freezing. But this is a solution that needs planning that starts years in advance. Lifestyle choices like smoking and drinking also affect the quality and quantity of the eggs in the ovarian reserve and may lead to premature menopause. Cutting down on these habits, and watching your weight can considerably help in improving your chances of conception.
Ferticare helps people with natural conception, IVF, IUI, Donor Sperm Donor Egg, and Surrogacy. We offer customized treatment that is right for you and your condition.
If you are struggling to conceive, or want to know more about how age is a factor in the fertility process, you can schedule a free consultation with our counselor or visit our website today – www.ferticare.in