Traffic Noise, Air Pollution Linked to Infertility Risk

TOPLINE:

Long-term exposure to particulate matter 2.5) is linked to a higher risk for infertility in men. Exposure to road traffic noise is associated with a higher risk for infertility in women aged > 35 years and possibly in men aged > 37 years.

METHODOLOGY:

• This nationwide prospective cohort study evaluated the association between long-term exposure to road traffic noise and PM_2.5 and infertility in 526,056 men (mean age, 33.6 years) and 377,850 women (mean age, 32.7 years) who were cohabiting or married, had fewer than two children, and lived in Denmark between 2000 and 2017.
• Residential exposure to road traffic noise (most exposed facade of the home) and PM_2.5 was estimated using validated models and linked to data from national registers.
• Diagnoses of infertility were identified in men and women from the Danish National Patient Register over a mean follow-up of 4.3 years and 4.2 years, respectively.

TAKEAWAY:

• Each 2.9 µg/m³ increase in the 5-year average exposure to PM_2.5 was associated with a 24% increase in the risk for infertility in men aged 30-45 years (adjusted hazard ratio [aHR], 1.24).
• No significant association was found between exposure to PM_2.5 and infertility in women.
• Each 10.2 dB increase in the 5-year average exposure to road traffic noise was associated with a 14% increase in infertility (aHR, 1.14; 95% CI, 1.10-1.18) in women aged 35-45 years.
• Exposure to noise was associated with a reduced risk for infertility in men aged 30.0-36.9 years (aHR, 0.93; 95% CI, 0.91-0.96) and an increased risk in those aged 37-45 years (aHR, 1.06; 95% CI, 1.02-1.11).

IN PRACTICE:

“As many western countries are facing declining birth rates and increasing maternal age at the birth of a first child, knowledge on environmental pollutants affecting fertility is crucial,” the authors of the study wrote. “It suggests that political implementation of air pollution and noise mitigations may be important tools for improving birth rates in the western world,” they added.

SOURCE:

The study, led by Mette Sorensen, of the Danish Cancer Institute in Copenhagen, Denmark, was published online on September 4, 2024, in The BMJ.

LIMITATIONS:

The study’s reliance on register data meant information on lifestyle factors such as alcohol use, body mass index, and smoking was unavailable. The lack of data on exposure to noise and PM_2.5 at work and during leisure activities may affect the size and statistical precision of risk estimates.

DISCLOSURES:

The study did not receive any external funding. The authors declared no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.