Smog’s Hidden Health Risks: How Air Pollution Could Impact Fertility in Men and Women, Experts Explain

Smog and Fertility: Experts Reveal How Rising Air Pollution Could Affect Reproductive Health

Air pollution is once again raising health concerns across India, with several cities experiencing elevated levels of fine particulate matter. On October 14, Delhi recorded an average Air Quality Index (AQI) of 181, placing it in the moderate category, according to the Commission for Air Quality Management. However, individual monitoring stations reported worse conditions.

Hourly PM2.5 concentrations also remained elevated in several cities, measuring 126.2 µg/m³ in Patna, 114.1 µg/m³ in Ludhiana, 108.5 µg/m³ in Delhi and 86.4 µg/m³ in Kolkata.

Although smog is widely associated with coughing, breathing difficulties and other respiratory problems, its potential impact may extend to reproductive health. Scientific research is increasingly examining whether prolonged exposure to air pollution is associated with changes in sperm quality, hormonal function, fertility treatment outcomes and pregnancy complications.

Fertility experts explain how polluted air may affect men and women, what current research reveals and how couples planning to conceive can take precautions.

How Does Air Pollution Affect Fertility?

Exposure to polluted air has been linked to several biological processes that may influence reproductive function. Fine particulate matter and other pollutants can contribute to oxidative stress and inflammation, potentially affecting reproductive cells and hormonal activity.

A Danish study involving more than 900,000 people found that men exposed to PM2.5 concentrations averaging 2.9 µg/m³ above the reference level over five years had a 24% higher risk of receiving an infertility diagnosis. The researchers did not find a similar association among women.

The findings highlight a possible connection between prolonged pollution exposure and male infertility, although they do not establish that air pollution directly causes infertility in every affected individual.

Dr Megha Jindal, Fertility Specialist at Birla Fertility & IVF, Noida, explains that the potential impact depends on how long and how intensely a person is exposed to polluted air.

“Smog and polluted air may affect reproductive health, especially in cities where bad air can last for weeks. It is contingent upon the duration and intensity of people’s exposure, but studies show that oxidative stress and inflammation are two mechanisms through which pollutants can interfere with reproductive function in women and men,” she says.

Impact of Smog on Male Fertility

Male reproductive health is one of the key areas being examined in pollution-related research. Studies have associated exposure to particulate matter and certain gaseous pollutants with changes in sperm concentration, motility and morphology.

These characteristics are important for sperm function, including the ability to reach and fertilise an egg.

Dr Kranthi Shilpa, Senior Consultant in High-Risk Obstetrics and Gynaecology, Laparoscopic Surgery and Infertility at CARE Hospitals, Banjara Hills, Hyderabad, explains that pollutants such as PM2.5 and nitrogen dioxide may contribute to inflammation and oxidative stress after entering the body through inhalation.

Oxidative stress can affect cells by overwhelming the body’s natural antioxidant defences. In sperm cells, this process may damage cellular structures and DNA, potentially influencing reproductive outcomes.

Some studies have also reported possible changes in reproductive hormones following exposure to environmental pollutants. However, scientists are still investigating the precise mechanisms and the extent to which these changes affect an individual’s ability to conceive.

Dr Prasanta Kumar Nayak, Regional Medical Head and Fertility Specialist at Oasis Fertility, Bhubaneswar, refers to a 2023 systematic review and meta-analysis examining ambient air pollution and semen quality.

The review found associations between exposure to pollutants, including particulate matter and sulphur dioxide, and changes in certain sperm parameters.

Such findings suggest that air pollution could be one of several environmental factors affecting male reproductive health. They do not mean that everyone exposed to smog will develop fertility problems.

How Air Pollution May Influence Female Fertility

Women may also experience reproductive effects associated with environmental pollution, although research findings vary across studies.

Fine particulate matter and other pollutants have been investigated for their potential effects on hormonal regulation, ovarian function and the biological environment in which eggs develop.

Researchers have also examined associations between air pollution and longer time to conception, fertility difficulties and adverse pregnancy outcomes, including preterm birth and low birth weight.

Pollutants may potentially influence processes involved in embryo implantation and early pregnancy development. However, the strength of the evidence depends on the pollutant studied, the duration of exposure and the reproductive outcome being examined.

Dr Nayak highlights a 2025 systematic review and meta-analysis involving women undergoing assisted reproductive technology. It reported associations between exposure to nitrogen dioxide and carbon monoxide during certain stages of fertility treatment and lower clinical pregnancy rates.

While these findings raise important questions, they do not prove that air pollution directly causes unsuccessful fertility treatment. Further research is needed to establish the relationship and understand how different pollutants may affect reproductive processes.

Experts emphasise that fertility is influenced by several factors, including age, hormonal conditions, existing medical problems and the reproductive health of both partners. Pollution should therefore be considered a possible contributing factor rather than the sole explanation for difficulties conceiving.

Ways to Reduce Pollution Exposure When Trying to Conceive

Although it may not be possible to avoid polluted air entirely, couples can take practical steps to limit exposure while protecting their overall health.

“Couples planning a pregnancy should treat air quality as one factor among several, together with age, existing medical conditions and lifestyle,” says Dr Jindal.

Her recommendations include:

Monitor air quality: Check local AQI readings and pollution alerts before planning outdoor activities.

Limit outdoor exposure: Reduce time spent outside when pollution levels are particularly high.

Avoid strenuous outdoor exercise: Choose cleaner environments or exercise indoors during periods of heavy pollution.

Consider a well-fitted N95 mask: It can help reduce inhalation of fine particles when outdoor exposure is unavoidable.

Improve indoor air quality: Use suitable air filtration where feasible and avoid indoor sources of pollution.

Dr Shilpa also recommends avoiding tobacco smoke, maintaining a balanced diet and exercising in cleaner surroundings. Adequate sleep and regular physical activity can support general health, although they cannot completely counteract pollution exposure.

Dr Nayak similarly advises people to adopt healthy lifestyle habits while reducing exposure to environmental pollutants wherever possible.

Should Couples Delay Pregnancy Because of Smog?

Experts do not suggest that air pollution alone should determine whether a couple attempts to conceive. Reducing exposure is a reasonable precaution, but avoiding smog cannot guarantee pregnancy or prevent every reproductive complication.

Age, hormonal health, medical history and male-factor infertility all need to be considered when assessing fertility. Couples who experience persistent difficulty conceiving should seek medical advice instead of assuming that air pollution is responsible.

A fertility specialist can evaluate both partners, identify possible contributing factors and recommend appropriate investigations or treatment.

“Over the long term, clean air benefits reproductive health, and personal precautions matter in the meantime,” says Dr Jindal.

As scientists continue to investigate the relationship between pollution and reproductive outcomes, limiting exposure remains a useful preventive measure. However, protecting fertility also requires greater efforts to improve air quality, alongside timely medical assessment and care for couples planning a pregnancy.