AGE AND FERTILITY
Dr. Devika Gunasheela
MBBS, MRCOG (Lond.), Fellow in Reproductive Medicine (RGUHS)
Gunasheela Surgical & Maternity Hospital
Does age affect fertility?
Age affects the ability of women to conceive and have a healthy baby. Age is the single important factor affecting a woman’s fertility. For men, age-related fertility decline is more subtle but does happen. Education and enhanced awareness of the effect of age on fertility are essential in counseling the patient who desires pregnancy.
When does fertility starts to decline in women?
Female fertility begins to decline many years prior to the onset of menopause despite regular ovulatory cycles. Although there is no strict definition of advanced reproductive age in women, infertility becomes a big issue after the age of 35 years.
In her early to mid-20s, a woman has a 25 per cent chance of getting pregnant every month. Female fertility generally starts to decline when a woman is in her early 30s, and the decline speeds up after the age of 35. By age 40, the chance of getting pregnant in any monthly cycle is down to around five per cent.
Does age affect the chance of success of IVF?
A woman’s age also affects the chance of success with IVF. The chance of a live birth resulting from one IVF cycle for women less than 30 years is about 35% – 40% and in women more than 40 years is about 7%.
For older women the chance of having a baby increases if they use eggs donated by a younger woman.
Why does fertility starts to decline as women age?
In women, eggs are of limited supply. Women are born with 10 – 20 lakhs eggs at birth and it decreases to 3 – 5 lakhs eggs at puberty, 25,000 eggs at the age of 37 years and 1000 eggs at menopause. As women age, the quality and quantity of eggs reduces. The quantity reduces as women are born with a fixed number of eggs for their whole lifetime. The quality reduces as the percentage of chromosomally abnormal eggs increases as woman’s age increases.
As age increases, the risks of other disorders that may adversely affect fertility, such as fibroids, tubal disease, and endometriosis, also increases.
Does advanced age in women increases the risks during pregnancy?
The risk of pregnancy complications increases with age too. The risk of miscarriage and chromosomal abnormalities in the fetus increase significantly from age 35 years. Complications such as gestational diabetes gestational hypertension, caesarean section, and stillbirth are also more common among older than younger women.
When and how does advanced age in male partners affect fertility?
Male fertility generally starts to decline around age 40–45 years when sperm quality decreases. Increasing male age reduces the overall chances of pregnancy and increases time to pregnancy and the risk of miscarriage and fetal death.
Children of older fathers also have an increased risk of mental health problems. Children of fathers aged 40 or over are five times more likely to develop an autism spectrum disorders than children of fathers aged 30 or less are. They also have a slightly increased risk of developing schizophrenia and other mental health disorders later in life.
How can we overcome the affects of age related fertility decline?
Women who want to delay having a child until their late 30s or early 40s may consider methods to preserve their fertility when they are young. One way is to freeze eggs, or embryos.
Women wanting to postpone childbearing have to fight against their biological clock. A younger woman, who wants to delay her child bearing because of career/personal goals, must undergo egg retrieval like in IVF and freeze her unfertilized eggs.
The only other option for men and women who are already old and infertile is to use sperm, eggs, or embryos donated by another man, woman, or couple. Using donated gametes or embryos makes the chance of successful pregnancy the same as for the person who donated the gametes.
What is social egg freezing?
Social egg freezing is a procedure done in younger women from whom eggs are extracted, frozen and stored. Women may choose to have the eggs thawed, fertilized via IVF, and transferred to the uterus as embryos to enable a pregnancy later. Social egg freezing helps women to balance their professional life and to enjoy their dream of motherhood later in life.
A woman who is not ready to have a child can choose to freeze eggs to try to preserve her ability to have a child later. Egg freezing typically works best for those in their 20s to early 30s, and is usually not recommended for women over 38 years.
Does leading a healthy life reverse the effect of age on fertility?
Smoking, unhealthy diet, obesity and stress may have an impact on the quality of eggs/sperm and may accelerate menopause. However, despite our best efforts to slow down or reverse the process, by eating healthy, exercising regularly, getting enough sleep, avoiding smoking, and adopting a lifestyle that reduces stress can improve your overall health but that does not offset the natural age related decline in female fertility, which can take place much sooner than most women expect.