New research on COVID during pregnancy and early brain development is getting media coverage. Some headlines sound alarming. Others sound reassuring. For families, this combination can be confusing and frightening.
This post walks through two studies in plain language: a 2026 brain imaging study from Children’s National Hospital in Washington, D.C., and a 2026 national study from the RECOVER-Pregnancy Consortium. It explains how they are similar and different, and what they do and do not tell us about children’s futures. Full citations are at the end of this post.
What were these studies about?
Both studies followed babies exposed to COVID during pregnancy and asked the same big question: Does that exposure change how a baby’s brain develops, or how they grow and learn in the first years of life?
One small study examined the brain itself using MRI scans and detailed developmental testing at age two. The other followed a much larger group of families across the United States and used standard, validated developmental checklists during the first year and a half of life.
Who were the study participants?
Study 1: Smaller group, deeper testing
- 142 pregnancies from one hospital
- 39 pregnant people had COVID during pregnancy; 103 were pregnant before the pandemic and did not have COVID
- Infections involved early pandemic variants; no vaccines were yet available
- Babies were born at term and were generally healthy
Because all infections occurred before vaccines existed, these findings reflect unvaccinated COVID exposure specifically, which matters for interpreting the results.
Study 2: Larger group, national picture
- 23 sites across the United States
- About 1,800 children enrolled; roughly 900 completed 12-month screening and 1,100 completed 18-month screening
- Most exposures occurred during the Omicron period, in the second or third trimester
- About 75% of participants were fully vaccinated
This study gives a broader view, with more families from more backgrounds and locations, using developmental screening tools that pediatricians use routinely.
What did the researchers do?
Study 1: Brain scans and toddler testing
Researchers did a brain MRI when babies were about two weeks old to measure the size of different brain areas. They followed the children to age two and gave a detailed developmental test that looks at thinking, language, and movement skills. Caregivers also filled out a questionnaire about the child’s emotions and behavior, including signs of anxiety or withdrawal.
Results were compared to a group of children born before the pandemic to see whether COVID-19 exposure during pregnancy made a difference.
Study 2: Developmental screening in a large group
Researchers used validated, standardized questionnaires that parents completed at 12 and 18 months, the same tools pediatric practices use nationwide. These tools work well for large, diverse groups, though they detect subtle differences less reliably than a detailed one-on-one evaluation.
Results were compared to a different group of children born before the pandemic to see whether COVID-19 exposure during pregnancy made a difference. This comparison group included low‑risk pregnancies and infants from the pre‑pandemic period.
What did each study find?
Study 1: Brain changes and more toddlers in the “at risk” range
In this study, just over half of exposed toddlers scored in the ‘at risk for delay’ range on the developmental assessment by age two. In the group born before the pandemic, about 14 out of 100 toddlers scored in that same range. That is a meaningful difference.
The study also found a chain of connections:
- Exposed babies showed different brain volumes at birth.
- Those brain differences correlated with lower thinking scores at age two.
- Lower thinking scores correlated with more internalizing behaviors, such as early anxiety, sadness, or withdrawal.
Brain size differences explained only a small part of the thinking score gap, which means other factors are likely involved. This does not mean every exposed child will have problems.
Study 2: Reassuring early screening results
In the larger national study, exposed and unexposed babies scored about the same on screening tools at 12 and 18 months and were referred for further evaluation at similar rates.
In this large national group, womb exposure to COVID did not predict worse screening scores through 18 months.
How are these studies similar?
Both studies looked at COVID during pregnancy and what it might mean for early child development. Both compared exposed and unexposed children.
And both reached the same conclusion: we need to follow these children longer to understand what early signals mean for learning, attention, and mental health in school.
How are they different?
The clearest way to see the difference is to think of them as two different tools.
Study 1 is a microscope. It followed a smaller group using detailed tools: brain MRI scans and a full developmental test at age two. It can catch more subtle changes, but its findings may not apply everywhere.
Study 2 is a wide-angle camera. It followed a much larger, more diverse group using standard screening tools at 12 and 18 months. It works well for spotting large, clear problems across the country, but it is less likely to catch smaller or earlier differences.
The studies also differ in age and context. One measured development at two years. The other examined infants at 12 and 18 months, an age when some developmental differences may not yet be visible.
They also reflect different phases of the pandemic. The first involved pregnancies during the early pandemic, before vaccines existed, when earlier variants were circulating. The second reflects mostly Omicron-era infections, which had a different biological profile and occurred under different conditions.
Researchers are still working to understand whether differences in outcomes relate to the variant, the timing of infection, or the circumstances surrounding it.
Why these studies are not contradictory
It can feel like one study says “Warning!” and the other says “All clear.” They do not actually cancel each other out.
A concern that appears at 24 months may not yet be visible at 18 months, and early differences do not automatically become lasting problems.
What the two studies together actually show is this: many exposed children show typical development on early screening, and there is enough signal in the research to warrant watching these children closely as they grow.
What "altered brain volume" actually means
Changes in brain volume sound alarming. It helps to know what that means and what it does not.
Brain volume refers to the size of different brain regions as measured on an MRI. Researchers can detect differences between groups, but size alone does not determine how well a brain works. The brain is highly adaptable in early life, and small structural differences do not automatically affect thinking, learning, or behavior.
In Study 1, the researchers estimated that brain size differences explained only a small part of the test score gaps between exposed and unexposed toddlers. Most of the difference likely came from other, unknown factors.
These are group-level patterns, not predictions about individual children. What the findings support is continued monitoring, not alarm
What "at risk" actually means
The term “at risk for developmental delay” can sound like a diagnosis. It is not. Here is what it means in practice.
Developmental tests compare a child’s skills with many other children the same age. Children usually fall into three broad ranges:
- Typical: skills are in the expected range for age.
- At risk: scores are lower than most other children, but not low enough to indicate a clear delay.
- Delay: scores are much lower than expected and often lead to a diagnosis and services.
A yellow light, not a red one
“At risk” means a child may be more likely to struggle later without support. It is a signal to monitor more closely and to access early intervention and school-based support if concerns continue.
It is not a prediction. Some children who score at risk catch up over time, especially with extra help. Others have ongoing learning, language, or behavior needs. No test can tell you which path any one child will take. What it can do is identify which children need closer attention right now.
Limits and unanswered questions
Limits to keep in mind
Study 1 compared babies born before COVID with babies born during the early pandemic. That period was stressful in many ways. It is hard to separate the effects of the infection from everything else families experienced at the time.
Both studies also ended early. Many learning and behavior differences do not appear until preschool or early elementary school. These studies may not have followed children long enough to see the full picture.
Screening tools catch large, clear problems but can miss smaller ones. And families who join research studies do not always reflect all families, which can shape what the results show.
What we still need to learn
Do early brain changes on MRI translate into learning or behavior differences in school? Which children face the most risk? Do factors like vaccination status, timing of infection, or access to support services offer protection? And which early interventions make the biggest difference for children exposed to COVID during pregnancy?
What families can do right now
Even with these limits, the research offers practical direction.
Keep going to well-child visits. These appointments track development over time, not just vaccines and growth. Take developmental screening seriously and fill out screening forms honestly. Trust your instincts. If you are worried about your child’s speech, movement, play, or emotional responses, say so even if a screening form looks fine. You know your child best.
Ask about early intervention. In the United States, children under three can receive early intervention services through a federally required program in every state. You do not need a diagnosis to request an evaluation. Ask your pediatrician how to connect with your state’s program. And remember: getting therapy, special instruction, or school supports means giving your child more tools.
If your child was exposed to COVID during pregnancy, staying connected to their care team, asking questions, and advocating for monitoring and support are meaningful things you can do right now. And if you need a community that understands, join our Caregiver Connect.
Sources:
Weiner S, Wu Y, Cheng JJ, Liggett M, McCants C, Adegbulugbe E, Mears A, Henderson D, AndescFavage N, Limperopoulos C. The COVID generation: the neurodevelopmental consequences of in-utero COVID-19 exposure. Brain Behav Immun. 2026 Mar;133:106238. doi: 10.1016/j.bbi.2025.106238. Epub 2026 Jan 1. PMID: 41483846; PMCID: PMC12862987.
Flaherman VJ, Reeder HT, Martin-Herz SP, Gallagher R, Cohen AK, Brown HE, Clifton RG, Fischbein N, Foulkes AS, Jacoby VL, Jain N, Beamon CJ, Bahtiyar MO, Chang A, Costantine MM, Cruz Irving A, Gibson KS, Hoffman MC, Hoffman MK, Hughes BL, Katz SD, Laleau V, Mendez-Figueroa H, Monteiro J, Okumura MJ, Pacheco LD, Palomares KTS, Parry S, Plunkett BA, Reddy UM, Rouse DJ, Saade GR, Sandoval GJ, Simhan HN, Skupski DW, Sowles A, Thorp JM Jr, Tita ATN, Weiner SJ, Wiegand S, Yee LM, Gross RS, Metz TD; RECOVER-Pregnancy Consortium. Intrauterine SARS-CoV-2 Exposure and Infant Neurodevelopment through 18 Months of Age: Findings from the Researching COVID to Enhance Recovery (RECOVER) Pregnancy Study. J Pediatr. 2026 Jan 19;292:114997. doi: 10.1016/j.jpeds.2026.114997. Epub ahead of print. PMID: 41565007; PMCID: PMC12962406.
