NUS study: Extreme hot weather affects Singapore men’s fertility and birth outcomes

SINGAPORE: Recent findings from a project led by the National University of Singapore (NUS) have uncovered significant correlations between punishing hot weather and adverse effects on couples’ fertility and birth outcomes.

The study, conducted by researchers from the NUS Yong Loo Lin School of Medicine as part of Project HeatSafe, sheds light on the potential repercussions of rising temperatures, particularly in a tropical climate like Singapore.

The study, which analyzed sperm samples from 818 men stored at the National University Hospital’s andrology section, revealed startling implications of exposure to extreme heat.

Researchers examined weather records to identify days with temperatures exceeding 29.8 degrees Celsius, finding that men exposed to such conditions had a 46% higher risk of low sperm count and a 40% increased risk of low sperm concentration.

Notably, this impact was more pronounced in men aged 25 to 35, the prime reproductive age group.

In light of these findings, researchers advised couples planning conception within the next one to three months to take precautions.

Recommendations include avoiding outdoor activities on extremely hot days, sleeping in cooler environments, and refraining from saunas, hot baths, and tight underwear during this period.

The study also examined the birth records of over 31,000 women, revealing that pregnant women tend to adopt protective measures, such as increasing air conditioning, to mitigate heat exposure.

Avoiding extreme heat during the third trimester was associated with a lower risk of premature births, highlighting the importance of heat management during pregnancy.

Beyond its impact on fertility and birth outcomes, Project HeatSafe also addressed heat strain risks among outdoor workers, particularly construction workers.

Researchers aimed to mitigate heat-related injuries and improve workplace safety through temperature monitoring devices and educational interventions.

Future efforts will extend to assessing the heat strain risk among gig workers, including food delivery riders.

As Singapore grapples with record-low fertility rates and the challenges posed by climate change, the implications of extreme heat on reproductive health and birth outcomes underscore the urgent need for proactive measures.

By raising awareness and implementing targeted interventions, researchers aim to safeguard the well-being of individuals and families in the face of escalating temperatures.