Heat Waves May Lead to Birth Defects, Low Birth Weight Babies

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We have long known that children and the elderly need to be checked on during prolonged and intense heat waves. Now, new research has found another group at acute risk from extreme heat: pregnant women.
Researchers from the University of California in San Diego found that longer and hotter heat waves, exactly the type that is commensurate with the climate crisis, might increase preterm births. As temperatures climbed higher and stayed that way for more and more days, the risk of preterm birth increased, according to the new study that was published in the journal Environment International, as The New York Times reported.
"We looked at acute exposure to extreme heat during the week before birth, to see if it triggered an earlier delivery," said first author Sindana Ilango, a Ph.D. student in the joint doctoral program in public health at UC San Diego and San Diego State University, in a statement. "We found a consistent pattern: exposure to extreme heat does increase risk. And, importantly, we found that this was true for several definitions of 'heatwave.'"
The senior author on the paper Tarik Benmarhnia, Ph.D., assistant professor of epidemiology at UC San Diego School of Medicine, added that this was the first study to look what particular factors of a heatwave increased the risk of preterm birth. "[N]o one had tried to figure out exactly what kinds of conditions could trigger preterm births," he said in the statement. "Is it the temperature? Is it the combination of the temperature and the humidity? Is it the duration of the heatwave? It's important to ask these questions to know when we need to intervene and inform pregnant people to stay inside and stay cool."
Birth before 37 weeks of gestation is a leading cause of infant death and illness. The World Health Organization has also said that preterm birth rates are increasing around the world. To examine how heat contributes, the researchers looked at California birth records from 2005 to 2013, comparing gestation length to heat records from 2005 to 2013, as The New York Times reported.
The scientists found a striking pattern — the rate of preterm deaths tracked right alongside increases in temperature or length of a heat wave. The New York Times provided an example: at an average a temperature of 88 degrees for two days 6.63 percent of births were preterm. However, at four days of 98-degree temperature, the rate was 7.46 percent.
"We were also surprised to note that the duration of the heatwave seems to be more important than the temperature threshold," said Benmarhnia in a statement. "We thought that temperature would matter the most, but it turns out that it has more to do with how long you're stuck with the high temperatures rather than how hot it is outside."
Similar research is looking at how extreme heat is affecting pregnant women, gestation-length and birth-weight in The Gambia, Africa, as Reuters reported. The African tropics are warming up faster than most of the world. Just recently, the mercury passed 108 degrees Fahrenheit during the cold season.
In The Gambia, many pregnant women have to work the fields to help support their family farms. When people are exposed to heat, more blood flows to the skin to allow heat to escape. This means decreased blood flow to the heart and internal organs, including potentially the placenta, said health researcher Ana Bonell, who is leading the study in The Gambia, as Reuters reported.
"I'm definitely seeing changes in the umbilical artery in about 30 percent of women," she said, although she has not analyzed the data yet, to Reuters.- Pregnant Women Have a Higher Risk of Delivering Early on ... ›
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By Aaron W Hunter
A chance discovery of a beautifully preserved fossil in the desert landscape of Morocco has solved one of the great mysteries of biology and paleontology: how starfish evolved their arms.
The Pompeii of palaeontology. Aaron Hunter, Author provided
<h2></h2><p>Although starfish might appear very robust animals, they are typically made up of lots of hard parts attached by ligaments and soft tissue which, upon death, quickly degrade. This means we rely on places like the Fezouata formations to provide snapshots of their evolution.</p><p>The starfish fossil record is patchy, especially at the critical time when many of these animal groups first appeared. Sorting out how each of the various types of ancient starfish relate to each other is like putting a puzzle together when many of the parts are missing.</p><h2>The Oldest Starfish</h2><p><em><a href="https://www.biorxiv.org/content/10.1101/216101v1.full.pdf" target="_blank" rel="noopener noreferrer">Cantabrigiaster</a></em> is the most primitive starfish-like animal to be discovered in the fossil record. It was discovered in 2003, but it has taken over 17 years to work out its true significance.</p><p>What makes <em>Cantabrigiaster</em> unique is that it lacks almost all the characteristics we find in brittle stars and starfish.</p><p>Starfish and brittle stars belong to the family Asterozoa. Their ancestors, the Somasteroids were especially fragile - before <em>Cantabrigiaster</em> we only had a handful of specimens. The celebrated Moroccan paleontologist Mohamed <a href="https://doi.org/10.1016/j.palaeo.2016.06.041" target="_blank" rel="noopener noreferrer">Ben Moula</a> and his local team was instrumental in discovering <a href="https://www.sciencedirect.com/science/article/abs/pii/S0031018216302334?via%3Dihub" target="_blank" rel="noopener noreferrer">these amazing fossils</a> near the town of Zagora, in Morocco.</p><h2>The Breakthrough</h2><p>Our breakthrough moment came when I compared the arms of <em>Cantabrigiaster</em> with those of modern sea lilles, filter feeders with long feathery arms that tend to be attached to the sea floor by a stem or stalk.</p><p>The striking similarity between these modern filter feeders and the ancient starfish led our team from the University of Cambridge and Harvard University to create a new analysis. We applied a biological model to the features of all the current early Asterozoa fossils in existence, along with a sample of their closest relatives.</p>Cantabrigiaster is the most primitive starfish-like animal to be discovered in the fossil record. Aaron Hunter, Author provided
<p>Our results demonstrate <em>Cantabrigiaster</em> is the most primitive of all the Asterozoa, and most likely evolved from ancient animals called crinoids that lived 250 million years before dinosaurs. The five arms of starfish are a relic left over from these ancestors. In the case of <em>Cantabrigiaster</em>, and its starfish descendants, it evolved by flipping upside-down so its arms are face down on the sediment to feed.</p><p>Although we sampled a relatively small numbers of those ancestors, one of the unexpected outcomes was it provided an idea of how they could be related to each other. Paleontologists studying echinoderms are often lost in detail as all the different groups are so radically different from each other, so it is hard to tell which evolved first.</p>President Joe Biden officially took office Wednesday, and immediately set to work reversing some of former President Donald Trump's environmental policies.
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