Is cortisol bad for babies?

Name similarity isn't that big a deal for many people with common names. There are 47,215 John Smiths, so people tend not to assume that any John Smith they read about is their John Smith.

When your name is uncommon, you learn to live with mistaken identity. There are only 41 Stephanie Pappases in the U.S., according to howmanyofme, and sometimes we get mixed up. I get congratulations about articles I haven't written. I get asked about my photography and legal services. I've never met her, but I once accidentally picked up another Stephanie Pappas' eyeglasses at an optical shop. I will not besmirch our shared good name by criticizing her taste in eyewear, but I was grateful once everything was sorted and I had my standard-issue oversized plastic professoriate frames.

Writer and non-actor Julie Beck learned of one of her online doppelgängers when she got an e-mail congratulating her about her casting in Peter Pan. She wrote about her extended name family in The Atlantic. "Each Julie Beck," this Julie Beck writes, "exists in her own social context, and these contexts rarely, if ever, overlap. But on the internet, they're all smooshed together. To Google, one Julie Beck is the same as another." 

That smooshing is how, a few weeks ago, I received a neat question from Lydia (hi Lydia!), asking about how cortisol affects fetuses. Lydia had found a different Stephanie Pappas' work on Live Science, specifically, a 2014 article called "The Truth About How Mom's Stress Affects Baby's Brain." 

My nametwin describes her then 7-month old daughter's participation in an ongoing experiment at the University of Denver. Her daughter was sitting in front of a dancing robot in 2014 because she was part of a "practice run" for a study of how fetuses exposed to high levels of cortisol in the womb react to unfamiliar situations throughout their lives. Lydia, writing me four years later, wanted to know more about how high levels of mom's cortisol affected babies. 

Elysia Davis, the lead author of that study, has made a career out of fetal cortisol levels. In a 2010 study, Davis and colleague studied 125 babies, first during pregnancy and then at 3, 6, and 12 months of age. Their findings suggest that cortisol plays a crucial role in fetal brain development. In healthy pregnancies, mothers' levels of cortisol increase throughout, peaking in the third trimester. That late burst of cortisol promotes organ development, a fact which you may be familiar with if you delivered a preterm baby and either you or the baby received cortisol injections to help speed along lung development. Davis and colleagues are now studying how cortisol levels in utero impact children throughout middle childhood and adolescence

So cortisol, in itself, is not just "not bad" for fetal development. It is, as Davis puts it, "necessary and beneficial for maturation of fetal organ systems." What's in question is how getting cortisol at the wrong time might lead to future cognitive impairment. Davis and colleagues have found that if you get a boost of cortisol in the third trimester, your brain benefits. Get that boost too early and your brain suffers. They're also now following older children and adolescents, investigating how long those cortisol effects last. 

Headline protection tip #1: Look for the limitations

You don't often see headlines like "Medical Researchers Added a Notable But Small Piece of Knowledge That May Help Future Researchers Make More Discoveries," but that's what most scientific research does. It builds, piece by piece, upon what research has come before. That's why you'll notice Davis and colleagues citing themselves in their work. Each new study is filling in the picture a little bit more. Or, more accurately, each new study contributes to the black and white sketch of the picture, which will be layered with more detail and color with every subsequent discovery. 

That's why it's so important to read about the limitations, which counterbalance splashy news findings by adding a lot of qualifiers to their conclusions. Davis' 2010 study, for example, includes three limitations. First, the study measured natural cortisol. In other words, researchers were not injecting mothers with cortisol to observe its effects. Second, the study included women with low-risk pregnancies, which do not fully represent all pregnancies. The first limitation suggests that researchers may not have isolated cortisol, that there may be other explanations for the cognitive effects on babies in their study. The second limitation implies that the cortisol issue may be even more pronounced in the population as a whole. The third limitation reminds readers that the study did not actually study fetal cortisol levels, but rather used maternal cortisol levels to draw assumptions about fetal cortisol.  A study that only measures mom's cortisol levels may not be providing a full picture of fetal cortisol levels. 

None of these limitations make the research "bad." They just show that the research is one tiny scribble within a much bigger picture. Other researchers will need to build on this research, finding ways to overcome its limitations. 

Headline protection tip #2: Compare impacts

If you read enough news reports about scientific findings, you'll start to see double. First, there's the headline-grabbing impact, like "Your Stress Is Harming Your Baby!" The headlines are not out to deceive, per se, but they are there to get your attention, and scaring you about how your behavior is affecting your fetus is one good way to get your attention. But when you keep reading, you'll note that good journalists explain scientific impacts in significantly less alarming terms. 

Davis' cortisol studies make for good headlines. Her work has been profiled at Newsweek ("How Stress Can Affect You and Your Unborn Baby"), Babycenter ("Your baby knows, and feels, when you’re stressed"), and Romper ("How Does Stress Affect Your Baby? Here's What Experts Want Pregnant Women To Know"). 

Sitting at the computer stress is not fight-or-flight stress, unless you're buying plane tickets to flee the country.  PC:  Pexels  for Pixabay

Sitting at the computer stress is not fight-or-flight stress, unless you're buying plane tickets to flee the country.

PC: Pexels for Pixabay

All of these articles explain cortisol's positive and negative effects before encouraging women to try not to stress over their pregnancies. But all of the articles are missing a larger discussion of the kinds of stresses that are likely to lead to elevated cortisol during the first trimester. The evidence is in the stock photos. 

A woman sits, head in hands, behind a MacBook and an expansive desk full of papers. A set of well-manicured hands holds a black and white nude pregnancy photo. A worried mom looks over the back of her infant, both clad in chic black and white stripes. A full-bellied mom smiles while receiving a shoulder massage. A crying blonde makes running mascara look pretty. 

These moms and moms-to-be? They look pretty much like the demographic likely to consume parenting blogs: reasonably well-to-do white women. Before we all start panicking that our stress over the alcohol we accidentally consumed before we were pregnant or the fender bender we were in during Week 10 or the epic fight we had with our spouse about nursery design in Week 12 have ruined our children's prospects for private kindergarten, we need to look past the headlines and think about what these conclusions mean. 

My namegänger's ready to help with that. 

She devotes nearly a third of her article to "the inequality of stress," citing research to demonstrate some possible systemic sources of increased cortisol during the first trimester: "stress, especially chronic stress, is not an equal-opportunity specter. Poor women are far more at risk."

My namefellow summarizes the possible applications of Davis' work:

...getting kids off on the right foot should start before birth. There are few studies on how to intervene with troubled pregnant women, Davis said, but possibilities include testing for depression during prenatal visits — just as postpartum depression screening is now de rigueur. Boosting social support for pregnant women might also help, Davis said.

My namemate is hinting at who, exactly, could be most impacted by Davis' findings: "troubled pregnant women" in need of "social support." The most concerning cortisol increases are likely to stem from the sort of chronic fight-or-flight experiences that come with poverty and related conditions. 

Headline protection tip #3: Consider the writer's expertise

When responding to Lydia's original e-mail, I suggested that even though she had the wrong Stephanie Pappas, she was probably in the right place for an answer. My homoname's job is to accurately summarize newsworthy information and present it in a clear and engaging format to readers. [She would probably describe her job more richly and eloquently than I am doing here.] Her job may sometimes be at odds with headline conventions that require every piece of news to be presented as earth-shattering or at least world-changing. 

My job is teaching parents how to be better researchers. That doesn't make my writing any better or worse than my the other Stephanie Pappas', but it does make it different. My headline about cortisol would look a little different: "Barring Systemic Social Factors Leading to Elevated Stress, Pregnant Women Probably Don't Need to Worry About Cortisol, But People Looking to Expand Opportunities for Children Should Work to Mitigate Poverty." That might be why I don't get published as often as my namealike.

If you're another of my doppelnämers with cool research to share, get in touch! And even if we don't share a name, please do share your research questions about pregnancy and/or early parenting.