Climate change is causing an increase in preterm births: Study

With the change in climate, the emergence of vector-borne diseases (insects-bearing diseases) like dengue and chikungunya, has spiked. This is subsequently leading to more than 7 lakh deaths annually.   That’s just the beginning though. The increase in temperature directly affects health by compromising the body’s ability to regulate its internal temperature. With the inability to control the internal temperature of the body, we become more prone to a cascade of illnesses like heat cramps, heat exhaustion, heatstroke, and hyperthermia during extreme heat and hypothermia and frostbite in extremely cold temperatures.   [caption id=“attachment_7656021” align=“alignleft” width=“380”]  Representational image.
Image by Pexels from Pixabay[/caption] And now we find that climate change is having an insidious effect on pregnant women.   Studies have claimed that, with the rise in temperature, the cases of preterm delivery have increased. Any birth that occurs at least three weeks before the due date is considered by doctors to be a premature delivery. Some of the complications that this could lead to are slow weight gain, immature lungs, poor feeding, etc.  

Heat and preterm labour

Long span research was conducted by Alan Barreca, an associate professor at UCLA’s Institute of Environmental Sustainability, and economist Jessamyn Schaller of Claremont McKenna College in a two-decade window, i.e., from 1969 to 1988, to find out the link between the change in temperature and preterm deliveries.   The researchers found that when the temperature exceeded or reached 32.2ºC (90ºF), the premature birth rate per 100,000 women increased by 0.97. It was also noted that on days when the temperature was hot but not extreme, the premature births increased by 0.57.   They further concluded that with an increase in temperature, the gestation period was decreased by two weeks. The gestation period is the time period of 40 weeks that it takes for fetal development, starting right from the conception till the day before the delivery.     Across the entire 20-year period of the study, around 25,000 infants were born prematurely every year, leading to the loss of more than 150,000 gestational days, all because of exposure to an exceptionally hot environment. Another long span study was conducted by scientists led by Dr Lyndsay A. Avalos in Northern California for a time window of 14 years, i.e., between January 1, 1995, to December 31, 2009, to investigate the impact of apparent temperature on spontaneous preterm delivery. Dr Lyndsay concluded the research by stating that with the increase in temperature by 10 °F (5.6 °C) during warm seasons, the cases of spontaneous preterm delivery increased by 11.6%.   All the preterm deliveries in this study took place between 28 and 37 weeks of gestational period, instead of 40.

The uncertain reason

Scientists have not been able to find the exact cause, but have laid down some possible reasons that could lead to premature labour:

• Scientists believe that due to the increased heat, the mother could have cardiovascular stress that in turn could trigger the body to go into labour early.
• The second theory proposed by the scientists is that the high temperatures could trigger an increase in the levels of the hormone oxytocin, which plays a role in inducing labour.
• The third theory stated that because of the hot temperature the mother might unable to sleep properly. This could increase the chances of preterm labour and preeclampsia (complication in pregnancy marked with high BP) in the mother.  

The alarming situation

It’s time to realize that climate change is real. And not only is it adversely affecting the environment but it has serious health implications as well, especially for the coming generation. For more information, please read our article on   Preterm Labour_. _  Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health.