Fewer boys born in Ontario after Trump’s 2016 election win, study finds

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Donald Trump’s election victory was a seismic shift in the U.S. political landscape and, for some, a source of uncertainty and stress that extended beyond the United States. But was it enough of a shock to temporarily lower the ratio of boys to girls born in Ontario?

That’s the surprising question raised by a pair of researchers at Mount Sinai Hospital who said they have found evidence for precisely such an effect in provincial birth records – an effect not experienced in conservative-leaning regions.

Ravi Retnakaran, a clinical scientist who led the study, said the team’s findings are in keeping with a series of published papers that link sudden and traumatic events, such as mass shootings and terrorist attacks, to changes in sex ratio. That Canada is a different country than the one that elected Mr. Trump in November, 2016, does not mean that its population was immune to his unexpected victory.

“The issue is whether it was seen as an adverse societal event,” Dr. Retnakaran said.

In their study, published Monday in the British Medical Journal, the Mount Sinai researchers present evidence that it was. Specifically, they show that the sex ratio of Ontario newborns shifted around March of 2017, when fewer boys than would typically be expected were born relative to girls. The timing of the deficit is what would be expected if pregnant women in the province experience elevated stress levels four months earlier, during a critical window in prenatal development when male fetuses are thought to be more at risk than females to environmental influences. The disparity lasted for three to five months.

Ontario sex ratios and the 2016

U.S. presidential election

Birth records reveal a temporary drop in the ratio of male to female newborns around March, 2017. A new study links the change to stress caused by the election of Donald Trump four months earlier – a potentially stressful event in liberal-voting areas. The trend was not observed in some of the most conservative regions of the province (dashed lines).

Number of newborn boys for every newborn girl, by month, liberal vs. conservative-leaning regions

conservative-leaning areas

liberal-leaning areas

1.16

Anticipated

effect

1.14

1.12

1.10

1.08

1.06

1.04

1.02

1.00

0.98

0.96

Nov. 2016

(Election)

March

2017

May

July

Sept.

THE GLOBE AND MAIL, SOURCE: RAVI RETNAKARAN

AND CHANG YE, BMJ OPEN

Ontario sex ratios and the 2016

U.S. presidential election

Birth records reveal a temporary drop in the ratio of male to female newborns around March, 2017. A new study links the change to stress caused by the election of Donald Trump four months earlier – a potentially stressful event in liberal-voting areas. The trend was not observed in some of the most conservative regions of the province (dashed lines).

Number of newborn boys for every newborn girl, by month, liberal vs. conservative-leaning regions

conservative-leaning areas

liberal-leaning areas

1.16

Anticipated

effect

1.14

1.12

1.10

1.08

1.06

1.04

1.02

1.00

0.98

0.96

Nov. 2016

(Election)

Jan.

2017

March

May

July

Sept.

THE GLOBE AND MAIL, SOURCE: RAVI RETNAKARAN AND

CHANG YE, BMJ OPEN

Ontario sex ratios and the 2016 U.S. presidential election

Birth records reveal a temporary drop in the ratio of male to female newborns around March, 2017. A new study links the change to stress caused by the election of Donald Trump four months earlier – a potentially stressful event in liberal-voting areas. The trend was not observed in some of the most conservative regions of the province (dashed lines).

Number of newborn boys for every newborn girl, by month,

liberal vs. conservative-leaning regions

conservative-leaning areas

liberal-leaning areas

1.16

Anticipated

effect

1.14

1.12

1.10

1.08

1.06

1.04

1.02

1.00

0.98

0.96

Nov. 2016

(Election)

Jan.

2017

March

May

July

Sept.

THE GLOBE AND MAIL, SOURCE: RAVI RETNAKARAN AND CHANG YE, BMJ OPEN

Steven Orzack, a population biologist with the Fresh Pond Research Institute in Cambridge, Mass., said the finding should be interpreted with caution, noting sex ratio studies have produced controversial results in the past. However, he did not discount the possibility that the study may have uncovered something more than a random blip in the data.

“It’s hard to know whether the association they describe is worthy of attention,” he said, adding that the biological significance of the results, “depends in part on interpreting them in light of all analyses, not just those revealing an association between the sex ratio and stress.”

Dr. Orzack said there was a need for more systematic scientific reporting of stressful events and their possible influence on the human sex ratio because analyses that show no influence are likely to be under-represented in the literature.

Dr. Retnakaran, a clinical scientist who specializes in diabetes, said the investigation was something of a side project for his lab. It was prompted by his experience on Nov. 9, 2016, the day after the U.S. presidential election, when everyone he saw around him was reacting to the outcome. Because he was aware of earlier research on adverse events and sex ratio, he wondered if the election might leave a similar mark.

The study is a statistical analysis that draws on Ontario birth records from 2010 to 2017 to demonstrate that something unusual may have been happening in the aftermath of the 2016 election. The team also looked at regional differences across the province and found the impact on newborn sex ratio did not show up in federal ridings that voted conservative in the preceding Canadian election the year before, which could mean that political differences played a role in the effect.

Robert Catalano, a professor of public health at the University of California Berkeley has published research linking the 9/11 terrorist attacks to sex ratio shifts in the state and, more recently, showing Mr. Trump’s election coincided with an increase in preterm births among Latina women in the United States. He said the Mount Sinai study added support to the body of evidence that human sex ratio can be affected by adverse events, though he expressed surprise at the cross-border nature of the phenonomenon.

“Why is it that the election of Donald Trump in the United States would show up in the biology of Canadian women?" he mused. “That’s a more profound question.”

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