Alisha Bradshaw doesn't know what it's like to be pregnant without the added worry of a global health crisis.
She had her first child, a healthy baby girl, during the summer of 2016, when a single mosquito bite could mean transmission of Zika — a virus known to cause devastating birth defects.
Four years later, Bradshaw, 44, of Brandywine, Maryland, was pregnant with her second child. This time, it was during the COVID-19 pandemic. While a can of insect repellent gave her a measure of control to protect against Zika, the coronavirus left her feeling particularly vulnerable.
"There were so many unknowns," Bradshaw said. "You just don't know who has it and who doesn't. You can take all the right precautions to keep your family safe, but you just don't know."
Unlike Zika, there is no evidence that COVID-19 infection during pregnancy directly impacts the growing fetus.
But the stress of being pregnant during the pandemic might.
"There is a lot of literature that supports the idea that stressors during pregnancy can have a deleterious effect on fetal brain development," said Charles Nelson, a professor of pediatrics and neuroscience at Harvard Medical School and Boston Children's Hospital.
Nelson explained that during times of extreme distress, the body releases a cascade of hormones into the bloodstream. Those stress hormones, which include cortisol, have the ability to cross the placental barrier between mother and baby.
Some areas of the fetal brain are quite receptive to stress hormones. One of those areas is the hippocampus, which plays a major role in learning and memory. A study published earlier this year in JAMA Pediatrics found marked differences in the growing fetal brains among pregnant women who were psychologically distressed.
"Among those pregnant women with high levels of stress," said study author Catherine Limperopoulos, "we could see negative impacts on the fetal brain," including a disruption to the brain's biochemistry.
The study findings were limited to pregnant women whose babies had developed congenital heart disease in utero, which can be a major source of stress for women during pregnancy.
Limperopoulos, who is also the head of Developing Brain Institute at Children's National Health System in Washington, D.C., has surveyed pregnant women about their stress levels regularly since 2014. Based on 163 responses from before the pandemic, 18 percent reported moderate to high levels of anxiety; 12 percent reported symptoms of depression; and 26 percent said they felt stressed.
When the pandemic hit, her team repeated the survey with 35 pregnant women. The results were striking, doubling and nearly tripling those percentages.
Among the 35 responses, 50 percent had moderate to high levels of anxiety; 35 percent felt depressed; and 71 percent were moderately to highly stressed.
"Even in the setting of a low-risk pregnancy, where the mom has no risk factors and the baby is developing well," Limperopoulos said, "there really is an alarming prevalence of mental health problems reported by these women."
Keri Toner, 33, of Washington, D.C., said the pandemic added an unprecedented level of stress. Her daughter, Lennon, was born a month ago.
It was her first pregnancy, which was "already a stress-provoking time," Toner recalled. "Then pandemic hit. You really feel like you've lost control."
For Bradshaw, of Maryland, the sources of COVID-19-related stress during her pregnancy were staggering. Six people in her family, including her husband, became ill with the coronavirus after attending a funeral in March.
At least three family members had to be hospitalized. Two of those loved ones died, including Bradshaw's father-in-law. Hospital rules prohibited family from being with him when he died. He did not live to meet his grandson, Immanuel, who was born in June.
The experience "was devastating," Bradshaw said. It's unknown whether she, too, was infected. Her doctor declined to test her because she had no symptoms of COVID-19.
The coronavirus has disproportionately impacted racial minorities, particularly Black Americans. The Centers for Disease Control and Prevention has reported that the proportion of Blacks with severe COVID-19 is greater than whites. Pre-existing conditions such as Type 2 diabetes, high blood pressure and obesity are all more prevalent in Black communities and all increase the risk for COVID-19 complications.
Bradshaw and Toner must pay close attention to their mental health now that they're both in the postpartum phase. Even under normal circumstances, the extreme exhaustion and physical toll of having a newborn can be particularly daunting.
Armed with the previous research that showed a link between maternal stress and impaired fetal brain development, Limperopoulos and her team at Children's National are now focusing on ways to alleviate stress during pregnancy.
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"Stress is a modifiable risk factor," she said. The group has begun a study called Project RESCUE, which aims to enroll up to 500 women.
Study participants will be randomized to different programs, such as mindfulness, yoga, breathing techniques and sleep health.
The research project will follow the women and their babies through age 3. "Our hope is to show that reducing levels of stress and anxiety can also have a positive effect on the development of the baby," Limperopoulos said.
Bradshaw has relied in part on friends who let her vent her frustrations — virtually, of course. (Even Bradshaw's baby shower had to be done through Zoom.)
But Bradshaw said her faith and the practice of meditation have helped the most.
"Even if it's only 10 minutes," Bradshaw said, stepping away to meditate "can help you gain some sort of stability when your day feels chaotic, just being able to breathe through it."
"I may be stressed," she said, "but I don't need to let stress overtake me."