New research looks at impact of summer heat and miscarriages

A new study suggests the risk of miscarriage may increase in the summer, which researchers say could indicate a link between extreme heat and pregnancy loss.
The study out of Boston University School of Public Health, published in the journal Epidemiology, looked at the seasonal differences in pregnancy data from more than 6,100 survey participants. They found that in North America, pregnant people have a 44 per cent higher risk of having an early miscarriage in the summer than in the winter – in particular, in the month of August in comparison to February. An early miscarriage for the purposes of this study was defined as occurring in the first eight weeks of pregnancy.
According to researchers, up to 30 per cent of pregnancies can end in spontaneous abortion, and up to half of all miscarriages are unexplained.
The risk of miscarriage at any point during the pregnancy was 31 per cent higher in August than in February.
Researchers also looked at geographical data and found that pregnant people who lived in the south or midwest United States, some of the hottest parts of the country, were more likely to experience a miscarriage in late August and early September.
“Any time you see seasonal variation in an outcome, it can give you hints about causes of that outcome,” the study’s lead author Dr. Amelia Wesselink said in a press release. “… Now we need to dig into that more to understand what kinds of exposures are more prevalent in the summer, and which of these exposures could explain the increased risk of miscarriage.”
Researchers said this study filled in gaps in past research, which tends to focus on data from pregnancy losses that occur in care at a hospital, which may exclude data from people who lost pregnancies very early on at home, or people who are not experiencing ongoing fertility issues causing miscarriage and therefore may not have sought care from a medical professional.
The study’s authors suggest that high temperatures may be a contributing factor to pregnancy loss, adding that while more research is needed to understand the possible link, health-care professionals and policymakers can begin to take action now to mitigate the effects of climbing temperatures on pregnant people.
“We know that heat is associated with higher risk of other pregnancy outcomes, such as preterm delivery, low birth weight, and stillbirth, in particular,” Wesselink said. “Medical guidance and public health messaging—including heat action plans and climate adaptation policies—need to consider the potential effects of heat on the health of pregnant people and their babies.”
CTVNews.ca Top Stories

BREAKING Time magazine names Taylor Swift 'Person of the Year' for 2023
Taylor Swift has dominated music charts, broken records and is performing in what is likely to be the highest-grossing tour ever -- and she's now named Time's 'Person of the Year.'
Pass federal gun bill without delay, shooting victim's father urges on anniversary of mass killing
The father of a woman who was fatally shot in October by her former partner is urging senators to pass a federal gun-control bill without delay.
Senators were intimidated, had their privilege breached, Speaker rules
Any attempt to intimidate a senator while in the process of fulfilling their duties is a breach of their privilege, even if the effort is ultimately unsuccessful, the Speaker of the Senate ruled Tuesday.
Here is Canada's unseasonably mild December forecast
December is predicted to be unseasonably mild across Canada, thanks to a "moderate-to-strong" El Nino and human-caused warming. Warming and precipitation trends will be stronger in some parts of the country than others, and severe weather is still possible, meteorologists say.
DEVELOPING Bank of Canada to announce interest rate decision today
The Bank of Canada is set to announce its interest rate decision this morning as forecasters widely expect the central bank to continue holding its key rate steady.
Two Canadian citizens confirmed dead in Antigua: Global Affairs
Global Affairs Canada has confirmed the death of two Canadian citizens in Antigua and Barbuda, news that comes amid reports from local officials that a woman and child drowned last week at Devil’s Bridge.
Affairs Nearly 3 in 10 Canadians have at least one disability: StatCan
The number of Canadians with at least one disability has doubled in 10 years, a reality that should push governments to help reduce barriers to accessibility, says the head of a human rights organization.
A court filing gives a rare look inside the FBI seizure of a lawmaker's phone in 2020 election probe
Just how hard did some Republican members of Congress work to keep President Donald Trump in office after his 2020 election loss? A court case is providing a few tantalizing clues.
Under Putin, the uber-wealthy Russians known as 'oligarchs' are still rich but far less powerful
When Vladimir Putin came to power in 2000, the outside world viewed those Russians known as o'ligarchs' as men who whose vast wealth, ruthlessly amassed, made them almost shadow rulers. A 'government of the few,' in the word's etymology. How much political power any of Russia's uber-rich now wield, however, is doubtful.