Nikhil Prasad Fact checked by:Thailand Medical News Team Sep 05, 2025 6 hours, 7 minutes ago
Medical News: COVID-19 and Pregnancy Risks
A new scientific investigation has revealed how COVID-19 directly affects the placentas of pregnant women, raising concerns about risks to both mothers and unborn children. The research was carried out by teams from the I. Horbachevsky Ternopil National Medical University in Ukraine and the Cedars–Sinai Medical Center in Los Angeles, USA. This
Medical News report highlights how infection with SARS-CoV-2, the virus that causes COVID-19, leads to structural damage in placental tissues, potentially disrupting the critical link between mother and fetus.
COVID-19 Found to Cause Severe Placental Damage in Pregnant Women
How the Study Was Conducted
The researchers studied 50 pregnant women—10 without COVID-19 and 40 who were infected during different trimesters. Using histopathology, electron microscopy, and immunohistochemistry, they examined tissue samples to uncover the extent of damage caused by the virus. Their work provided clear evidence that the timing of infection plays a major role in how much harm occurs.
Key Findings in the First Trimester
Women who caught COVID-19 in the first trimester showed swelling of placental tissue, known as villous edema, in over 64% of samples. This swelling disrupts the flow of nutrients and oxygen. Many placental cells also showed signs of necrosis, where tissue begins to die, and early blood clots were detected in the vessels. Under the microscope, researchers found damaged mitochondria—the energy factories of cells—indicating stress and destruction at the cellular level.
Damage in the Second Trimester
Infections during the second trimester produced even more concerning results. Nearly half of the samples displayed severe blood clots, while others showed chorangiosis, an abnormal increase in blood vessels within the placenta. These changes suggest the placenta was trying to compensate for poor oxygen supply. Microscopic studies revealed ruptured membranes, vacuoles inside cells, and apoptotic—or dying—trophoblasts, which are vital for maintaining the barrier between mother and child.
Third Trimester Outcomes
The third trimester proved the most destructive. More than half of the samples contained thrombosis and chorangiosis, combined with widespread necrosis and inflammation. The ultrastructural studies revealed shrunken and dead nuclei in placental cells, fragmented microvilli, and thickened or destroyed basement membranes. These disruptions weaken the protective barrier and could directly lead to miscarriage, stillbirth, or impaired fetal growth.
Molecular Insights
The study also measured proteins linked to blood vessel health. Annexin A2, which helps prevent clotting, was found in very high levels, suggesting the placenta was attempting to repair itself. Another protein, sclerostin, usually linked to bone health, was also increased in infected placentas, hinting at a broader disruptio
n of normal biological processes caused by the virus.
What the Findings Mean
The researchers concluded that COVID-19 causes nonspecific but highly damaging changes in placental tissue, mostly by impairing blood flow. While these problems can occur in normal pregnancies, they were far more frequent and severe in COVID-19 cases. The worst damage appeared in the third trimester, with evidence of widespread fibrosis, edema, and breakdown of the fetoplacental barrier. These disruptions may explain the higher rates of stillbirth, preterm delivery, and pregnancy complications linked to COVID-19 worldwide.
The study findings were published in the peer reviewed International Journal of Molecular Sciences.
https://www.mdpi.com/1422-0067/26/17/8596
For the latest COVID-19 News, keep on logging to Thailand
Medical News.
Read Also:
https://www.thailandmedical.news/news/covid-19-infection-during-pregnancy-alters-placental-genes-and-may-raise-risks-for-the-baby
https://www.thailandmedical.news/news/new-alarming-case-shows-omicron-and-newer-sars-cov-2-strains-can-still-damage-placenta-in-pregnant-women
https://www.thailandmedical.news/news/american-study-discovers-that-sars-cov-2-infections-impairs-antiviral-innate-immune-gene-expression-in-the-placenta
Share
Tweet
Share
