Women’s Age and Fertility: How It Impacts Reproductive Health

Fertility is influenced by many factors. Some of these factors like weight and lifestyle can be controlled while others cannot be controlled. Age is one such uncontrollable factor that affects fertility rates of both men and women. However, age affects female fertility much more than male fertility.

Keep reading to understand women age and fertility—how does age affect female fertility?

Does the Age of a Woman Affect Fertility?

Yes, age is one of the most crucial factors that influences a female’s fertility. There are other factors that can influence the fertility rates of a woman and the chances of her having a healthy baby, but the effect of age on her fertility can’t be overridden.

Recent studies show that more and more females are delaying childbirth until they are in their late 30s or 40s due to several reasons. This gradual shift in the average childbearing age has created a rise in fertility issues among couples worldwide.

Impact of Aging on Women Fertility

Women are born with approximately 2 million ovarian follicles in their ovaries. Before a girl reaches puberty, about 11,000 ovarian follicles die every month. Thus, in her teenage years, a woman has only about 300,000 to 400,000 ovarian follicles available. From this point onwards, about 1000 ovarian follicles are utilised every month.

This phenomenon cannot be controlled. It has nothing to do with any form of birth control, pregnancy, hormone production, health, lifestyle or nutritional supplements. Which is why, as a woman grows older, the number of good ovarian follicles available reduces. Eventually, a woman reaches menopause when she has no viable ovarian follicles left.

About 1 in every 4 healthy couples who are in their 20s or early 30s will likely get pregnant in any given menstrual cycle if they engage in unprotected sexual intercourse regularly. This likelihood decreases to about a whopping 1/20 for couples who are in their 40s and engage in regular sexual intercourse. There is a natural decline in a male’s fertility rates as they age, but their decline is not as steep or as predictable as a female’s.

How Does Age Cause Changes In Women's Fertility?

Are you wondering about what is the importance of age in female fertility? Here is how the fertility of a woman is affected with increasing age:

1. Quantity of Ovarian follicles 

From the time a female is born to when she gets her first period, the total number of ovarian follicles in her ovaries reduce from 2 million to about 2,50,000. Despite the fact that the ovaries release only 1 ovarian follicle in each ovulation cycle, a few hundred ovarian follicles are lost each month. The process of menstruation continues till menopause when she stops ovulating completely.

2. Quality of Ovarian follicles 

With increasing age, the number of ovarian follicles in a female’s ovaries decrease overtime in addition to a decline in the quality of her ovarian follicles. This gradual decline in quality starts when the female turns 35.

Women Reproductive System and Age

As you are now aware, a female is born with a lifetime supply of ovarian follicles in her ovaries. This means that there is a finite number of ovarian follicles in a female’s body. These ovarian follicles start to mature and ovulate one-by-one after puberty. The Women age and fertility is released in the hopes of being fertilised and a successful pregnancy. Each month, the body prepares the uterine lining for the implantation of the fertilised egg when a female starts to menstruate. If the egg is fertilised, it usually implants in the uterine lining, but if the egg isn’t fertilised, the body prepares to shed the uterine lining. This process repeats until the ovarian egg reserve is exhausted and menopause occurs.

With each menstruation cycle, a female’s egg reserve decreases gradually in quantity and quality. A woman’s peak fertility years start from late teens and go up to her late-20s, after which her fertility starts to decline gradually with advancing age. A steep decline happens after she turns 35, and her chances of getting pregnant naturally after 40 reduce to negligible.

How Does Age Affect Infertility?

With increasing age, the chances of you experiencing infertility increase.

Relation Between Age and Pregnancy

A woman can technically conceive a child any time after her first menstrual cycle. This usually occurs in the early teenage years. A woman is believed to be most fertile in her 20s. However, the impact of age on fertility in women is not uniform. At the age of 30 years, a woman has a 20% chance of conceiving each month. After she reaches 35, the rate at which a woman’s fertility decreases speeds up. Around the time she turns 40, a woman has only about a 5% chance of conceiving each month.

Additionally, as you age, your chances of having multiple babies in a pregnancy increases. With increasing age, there is an increased chances that the ovaries might release more than 1 egg in an ovulation cycle. Besides, certain fertility treatments like IVF also increase the chances of multiple pregnancy in older women. Multiple pregnancies increase the risk of premature birth and miscarriages among others.

Women who get pregnant at 40 years of age or later are recommended to give birth at 39 weeks instead of the usual 40 weeks from the first day of their last menstrual period. This is done to reduce the risk of stillbirth with the help of labour induction techniques. Additionally, such women are recommended to go for a caesarean birth instead of a vaginal birth if they have certain pregnancy complications. However, vaginal birth is also an option for older women who have little to no pregnancy complications.

Age and Other Reproductive Risks in Female

Along with difficulty conceiving, age also increases the chances of a miscarriage, stillbirth and complications related to pregnancy such as placenta praevia, gestational diabetes, and placenta abruption. As her age increases, the cells in a woman’s body also start dividing abnormally. This may distribute genetic material in unequal amounts thus causing an increased risk of genetic abnormalities in the unborn child.

Although the risk of having a baby who has a chromosomal abnormality is low, increasing age increase this risk. A female’s chances of having a baby with damaged, missing, or extra chromosomes increases with her age. Having a chromosomal abnormality can lead to congenital genetic disorders such as Patau syndrome, Edwards syndrome, and Down syndrome.

Females who are aged 35 years or older and have a predisposition to preeclampsia may be required to take suitable medication prescribed by their obstetrician-gynaecologist to reduce their risk of preeclampsia.

When to Consider an Infertility Evaluation?

Women’s age and fertility are closely related in almost every aspect; if you are in your mid-late 30s and haven’t been able to conceive successfully even after having regular unprotected sexual intercourse for 6 months or more, you are advised to consult a fertility specialist and get an evaluation for infertility. You can visit your nearest Nova IVF Fertility centre or book an appointment online through the official website to schedule a comprehensive infertility evaluation.

Females who are in their 40s are recommended to get an infertility evaluation beforehand if they plan to get pregnant. Additionally, women who have endometriosis or other health problems that may affect your fertility are also advised to consult a fertility specialist from Nova IVF Fertility centre before trying to conceive.

Fertility Timeline of a Woman

Here is a brief overview of the fertility timeline of a woman:

From the Age 18 to 24

During this stage, a female’s body is at the best stage for conceiving. The best ovarian follicles mature first; thus, the eggs that are produced during the early stage of your life are usually of high quality.

From the Age 25 to 30

The chance of your conception gradually declines as you grow older. However, late-20s is a good time to get pregnant without medical intervention. About 40-60% of the couples who are aged under 30 and generally healthy can conceive within the first 3 months of trying to conceive.

From the Age 31 to 35

During this stage, you have ample ovarian follicles of decent quality, which means that females of this age group have a relatively high chance of conception.

From the Age 35 to 40

The most significant decline in fertility rates can be observed after a woman turns 35. During this stage, an increase in the chances of chromosomal abnormalities, miscarriages, and other risks can be observed.

From the Age 41 to 45 and Above

This stage in a woman’s life is the most difficult ones for conception as the body is nearing menopause. The quality of remaining ovarian follicles in a female’s body is usually quite low during this stage of their lives. Women who are aged 40 or above are recommend to use healthy donor eggs for their IVF cycles while considering fertility treatment.

Women Age and IVF Success

Does age affect pregnancy chances of women who are trying IVF treatment? Let’s understand the relation between a woman’s age and her IVF success chances.

In vitro fertilisation (IVF) is a type of fertility treatment that can help couples who are experiencing infertility conceive and work towards building a family. The age of a woman is also the most influential factor in determining the success rates of an IVF cycle in her fertility treatment.

Average chances of success for 1 IVF cycle are listed below:

• About 43% for women who are aged between 30 and 34 years
• About 31% for women who are aged between 35 and 39 years
• About 11% for women who are aged between 40 and 44 years

If you have passed the peak of your fertility, i.e. your mid-20s, and wish to get pregnant, you can consider using eggs donating by a younger woman for your IVF cycle to increase your chances of getting pregnant.

In Vitro Fertilisation Could be Your Saviour!

The good news is that there are still ways women can have children in their later 30s. The type of fertility treatment recommended depends on the woman’s age and other factors that could be influencing her fertility. In-vitro fertilisation is one of the most popular means of treating infertility caused by advancing age.

However, it is important to note that age can influence the results of IVF treatment as well. For this reason, if a woman plans to have children late in her life, it may be a good idea for her to freeze her ovarian follicles. Women may also choose to undergo the IVF treatment with donor ovarian follicles.