Getting pregnant at 20, 30 or 40, what you need to know
There is a definite link between age and fertility for both men and women. Getting pregnant at 20 is much less complicated than getting pregnant at 40. This is how fertility decreases as a function of age.
Nowadays there is an increasing tendency to delay the moment of maternity and paternity, placed in the background to give priority to the search for economic stability (increasingly difficult to achieve given what the world of work offers).
At birth a woman has about 1 million immature follicles which are reduced to only 400,000 at the first menstruation (the menarche) which occurs on average at 12 years of age.
At each menstrual cycle, a few hundred oocytes are lost and only the best follicles will become the ones that will undergo ovulation , releasing the mature egg cells ready to be fertilized. The other follicles that start to mature without success at each menstrual cycle are reabsorbed by our body.
Males, on the other hand, continue to produce new sperm for most of their adult life.
As a woman ages, her body has fewer and fewer follicles available and therefore less chance of maturing healthy and strong egg cells.
Most women start looking for their first child between the ages of 30 and 40, with an increasingly marked tendency to move towards 40, an age that is not the best in terms of available follicles. Which is why many couples find themselves dealing with fertility problems .
Getting pregnant based on a woman’s age
Age has a greater influence on women than on men. We also know that with the arrival of menopause, fertility is completely lost, so nature has really set a limit beyond which a woman’s body is no longer able to procreate naturally.
According to a 2004 study by the epidemiologist Henri Leridon published in Human Reproduction , considering a typical situation, without pathologies, with a regular menstrual cycle and targeted intercourse:
- Getting pregnant at 30
- 75% will become mothers within a year of targeted attempts
- 91% will become mothers within 4 years of targeted attempts
- Getting pregnant at 35
- 66% will become mums within a year of targeted attempts
- 84% will become mums within 4 years of targeted attempts
- Getting pregnant at 40
- 44% will become mums within a year of targeted attempts
- 64% will become mums within 4 years of targeted attempts
- Women under the age of 30 have about a 25% chance of getting pregnant naturally per menstrual cycle.
- This probability drops to 20% for women over 30
- At age 40, the chance of getting pregnant naturally each month is only 5% .
Getting pregnant between the ages of 18 and 24
If we want to define a best biological age for conception it is this age range, from 18 to 24 years.
The best ovarian follicles are the first to mature, so egg cells that are produced at a young age are more likely to be of high quality.
Having a child at this age will reduce the risk of:
- birth defects
- chromosomal problems
- fertility problems
Getting pregnant from 25 to 30 years old
40-60% of healthy couples under the age of 30 manage to conceive a child in the first 3 months of trying (source: https://www.nichd.nih.gov/health/topics/infertility/conditioninfo/ common )
Getting pregnant from 31 to 35 years old
In this age group the chances of natural conception are still high.
The woman still has many quality eggs, but the chances of pregnancy will start to decrease steadily. As you can see in the graph, women’s fertility decreases gradually but significantly starting at approximately age 32 and decreases more rapidly after age 37. (source: Fertility and Sterility )
Getting pregnant from 35 to 40 years old
The greatest drop in fertility occurs in the late 30s and early 40s.
The chances that a woman in her 40s will be able to conceive on their own is about half that of a woman in her 20s.
A 2003 scientific publication finds that 60% of couples in this age group are able to conceive naturally within a year of focused attempts, while 85% will be able to conceive within two years of focused attempts.
However, at this age, the risks of chromosomal problems are higher due to the lower quality of the oocytes. This means that the risks of miscarriage or abnormal pregnancy are higher.
Getting pregnant from 41 to 45 years old
More and more women have a child in this age range precisely because, for various reasons, the decision to have a child is reached late.
At this age, however, the woman’s body is preparing for menopause . The ovaries are running out of follicles or are approaching the end of the ovarian reserve which decreases with each menstrual cycle. Upon reaching the age of 50 or so, there are hardly any available follicles left.
Babies born to people in this age group are at increased risk of birth defects and pregnancy complications. Furthermore, spontaneous abortions and chromosomal abnormalities affecting the embryos increase significantly.
Older age also increases the mother’s risk of complications, such as diabetes, high blood pressure , and preeclampsia .
Why does the probability of pregnancy decrease with age?
A 40-year-old woman today is nothing like a woman of her peers who lived 100 years ago. At 40, the modern woman is active, beautiful, physically healthy, attractive.
But the outward appearance and physical form does not coincide with the state of the reproductive organs that feel the progress of age.
In fact, we women are born with a wealth of egg cells that gradually decreases . At the age of 35, the drop is so drastic that the reserve of ovules ends long before menopause .
Furthermore, the older the eggs are, the more likely they are to carry chromosomal abnormalities or to have cell division problems after fertilization, generating spontaneous abortions .
However, it is fair to point out that the quality of egg cells is not as linked to age as the number is and depends from woman to woman.
43-year-old women may still have many optimal eggs, while others twenty years younger may have poor quality eggs. We always talk about statistical values.
Another factor to consider is ovulation , which does not happen as punctually as before over the years . Especially in the years preceding menopause (perimenopause), ovulations may be rare.
If targeted hormone dosages are performed, however, it is possible to understand whether menopause is approaching or not.
Help to improve fertility, however, comes from nutrition and a healthy lifestyle. In fact, it has been shown that the use of vitamin and mineral supplements can increase the likelihood of pregnancy.
Male age and fertility
On the male side, however, age affects fertility to a lesser extent because sperm are continuously produced by the male reproductive organs. However, the quantity and quality can deteriorate with age .
Indeed, in elderly men the concentration and motility of sperm decreases and sperm with chromosomal abnormalities may be more frequent.
A recent study also showed that 35-year-old males have a 50% reduced conception rate compared to 25-year-old males.
Kathryn Barlow is an OB/GYN doctor, which is the medical specialty that deals with the care of women's reproductive health, including pregnancy and childbirth.
Obstetricians provide care to women during pregnancy, labor, and delivery, while gynecologists focus on the health of the female reproductive system, including the ovaries, uterus, vagina, and breasts. OB/GYN doctors are trained to provide medical and surgical care for a wide range of conditions related to women's reproductive health.