Infertility is a condition that affects millions of people worldwide. According to the World Health Organization (WHO), infertility is clinically defined as the inability to achieve pregnancy after 12 months or more of regular unprotected sexual intercourse. Some key statistics on infertility rates globally include:
Global infertility rates
- It’s estimated that 8-12% of couples worldwide experience infertility.
- This equates to 60-80 million couples globally.
- Infertility rates vary widely between regions and countries. Rates tend to be higher in developing countries and lower in developed countries.
- Infertility rates range from 3.5-16.7% in developing countries and 6.9-9.3% in developed countries.
So in total, roughly 50-70 million couples or 100-140 million individuals worldwide are affected by infertility. However, these numbers are estimates only as there is limited data on infertility rates, especially in developing countries.
Infertility rates by region
Here is a breakdown of estimated infertility rates by major world regions:
| Region | Estimated infertility rate |
|---|---|
| Africa | 9-30% |
| Asia and Pacific | 6.8-12.5% |
| Europe | 9-15% |
| Latin America and Caribbean | 7.4-8.5% |
| Middle East | 5.4-12.1% |
As shown, infertility rates vary widely across regions from as low as 5% in parts of the Middle East to as high as 30% in some African countries.
Infertility rates in select countries
Here are some statistics on infertility rates in select countries worldwide:
- United States: 6.7%
- United Kingdom: 8-16%
- France: 14%
- Germany: 9%
- Italy: 9-19%
- Australia: 9%
- China: 12.5%
- Japan: 3.5-16.7%
- Nigeria: 20-30%
- South Africa: 9-12%
- India: 8-12%
Again there is significant variation between countries. Developed Western nations like the US, UK and Australia tend to have lower rates around 9%. Whereas some developing countries like Nigeria have very high rates up to 30%.
Primary vs secondary infertility
There are two types of infertility:
- Primary infertility – when a couple has never been able to conceive.
- Secondary infertility – when a couple has had at least one successful pregnancy but is unable to conceive again.
Around one third of infertility cases are due to primary infertility. The remaining two thirds are due to secondary infertility. Rates of secondary infertility are rising globally as more couples delay having children, increasing their risk of age-related fertility decline.
Causes of primary and secondary infertility
The causes of primary and secondary infertility can differ.
Primary infertility is often caused by:
- Abnormalities or absence of reproductive organs (e.g. uterus, ovaries, testes)
- Hormonal imbalances or disorders
- Genetic defects
- Poor sperm or egg quality
- Pelvic infections like chlamydia and gonorrhea
- Endometriosis
Secondary infertility is often caused by:
- Age-related fertility decline, especially in women over 35
- Tubal blockages or damage after infections
- Sperm quality decline in men over 35
- Complications from past pregnancies or surgeries
- Endometriosis
- Polycystic ovary syndrome (PCOS)
There can be overlap between the causes of primary and secondary infertility. But secondary infertility is more strongly linked to age-related fertility issues.
Age and fertility
Age is one of the strongest factors impacting fertility in both men and women. Fertility starts to gradually decline from the late 20s and drops rapidly after 35.
Here are some key facts on how age impacts fertility:
- For women, the chance of conceiving naturally drops from around 15-20% per cycle in the late 20s, to 5% per cycle by age 40.
- Risk of miscarriage also rises from 10% at age 30, up to 75% by age 45.
- Male fertility declines gradually after 35, with sperm quality deteriorating with age.
- Couples with an aging male partner may require assisted reproductive technology.
- By age 43, 90% of a woman’s eggs are chromosomally abnormal, contributing to almost all age-related infertility.
Ovarian reserve testing can check a woman’s remaining supply of viable eggs. Low counts indicate diminished fertility. However, total loss of fertility occurs around the average age of menopause at 51 years.
Fertility rates by female age
This table shows estimated natural pregnancy rates by age for women trying to conceive:
| Female age | Chance of conceiving naturally per cycle |
|---|---|
| 20-24 years | 20-25% |
| 25-29 years | 15-20% |
| 30-34 years | 10-15% |
| 35-39 years | 5-10% |
| Over 40 years | Less than 5% |
This demonstrates the steady age-related fertility decline in women. Male fertility also declines with age but not as abruptly as female fertility.
Lifestyle factors and infertility
Along with age, certain lifestyle factors can negatively impact fertility for both men and women.
Some key lifestyle risks include:
- Smoking – lowers sperm count and quality in men. In women it can damage eggs and fallopian tubes.
- Alcohol – heavy drinking reduces testosterone and sperm quality in men. It can also disrupt the menstrual cycle and ovulation in women.
- Obesity – being overweight causes hormonal changes that hinder ovulation and pregnancy.
- Chronic stress – elevated stress hormone levels inhibit fertility in both sexes.
- Tight underwear – wearing tight underwear raises scrotum temperature, lowering sperm production in men.
- High caffeine intake – too much caffeine may disrupt ovulation and increase miscarriage risk.
Leading a healthy lifestyle without smoking, maintaining a healthy BMI, limiting alcohol and caffeine intake, and managing stress are important for optimizing natural fertility potential.
Global trends influencing infertility
Some global societal trends that may influence infertility rates in coming decades include:
- More women delaying childbirth for education or career reasons
- Greater awareness and diagnosis of infertility
- Higher rates of obesity and metabolic disorders like PCOS
- Sexually transmitted infections remaining common
- Environmental toxins potentially disrupting reproductive function
- Stress and mental health issues increasing
These factors create a complex interplay between lifestyle, environment, health and age that shapes fertility outcomes. Some predict a continued gradual increase in age-related infertility worldwide, especially secondary infertility.
However, improving awareness and access to assisted reproductive technology can offset some of the age-related decline. IVF success rates now allow many women to conceive in their 40s, which was extremely rare a generation ago.
Infertility diagnosis
If a couple has difficulty conceiving, a series of diagnostic tests can help identify the potential cause of infertility so appropriate treatment can be provided.
Typical infertility investigations may include:
- Assessment of ovulation and ovarian reserve in women
- Hormone level checks for imbalances
- Pelvic exams to check for structural problems
- Imaging tests like a hysterosalpingogram to check the fallopian tubes
- Semen analysis to assess sperm count and quality
- Genetic testing for issues like Y chromosome microdeletions
- Testing for infections like chlamydia
Once diagnosed, many causes of infertility can be successfully treated through medical therapies, surgery or assisted reproduction procedures like IVF. Although some cases remain unexplained.
Global disparities in infertility treatment
Access to high quality infertility treatment is extremely unequal globally. The vast majority of assisted reproductive procedures like IVF occur in developed countries.
Some key disparities include:
- Over 80% of IVF procedures are performed in Europe, USA, Australia and other developed nations.
- Many lower income countries have no IVF facilities and limited infertility treatment options.
- In Africa, 34 countries have no IVF services. Treatment is often prohibitively expensive if accessible.
- Cultural stigma around infertility also prevents treatment seeking in some regions.
- Prevalence of untreated infections is higher in poorer countries, increasing infertility risk.
Lack of equal access to assisted reproduction results in higher rates of involuntary childlessness globally. Addressing disparities requires improving education, reducing stigma, increasing funding and building local medical capacity.
Psychological impact of infertility
Alongside the physical challenges, infertility can deeply impact mental and emotional wellbeing for both women and men.
Common psychological effects may include:
- Stress, anxiety and depression
- Low self-esteem and feelings of inadequacy
- Grief, anger and resentment
- Marital strain and sexual intimacy issues
- Social isolation and withdrawal
- Obsessive focus on getting pregnant
Counselling and support groups often help couples cope with the complex emotions surrounding infertility. But the experience can be a profound life crisis.
In cultures where motherhood defines a woman’s worth, infertility may lead to even deeper psychosocial trauma. Patriarchal societies stigmatizing childless women as ‘barren’ exacerbate psychological damage.
With supportive personal and clinical care, couples can achieve parenthood through Assisted Reproductive Technology (ART) or build a life without children. But the emotional scars of infertility may linger.
Conclusion
In summary, infertility affects 8-12% of couples worldwide – equivalent to 60-80 million couples globally. Exact rates vary across regions and countries based on access to healthcare and cultural factors.
Primary causes include age-related decline, reproductive health issues, lifestyle risks and untreated infections. Infertility rates may continue rising slowly due to delayed childbearing and other societal shifts.
While great advances in Assisted Reproductive Technology have been made, huge disparities remain in access to treatment globally. Alongside medical interventions, caring for the psychological and social impact of infertility is vital for patient wellbeing.
With expanded research and healthcare access, the suffering caused by infertility worldwide can be further minimized. But it may remain an enduring life crisis affecting millions of men and women across the globe.