Researchers at Fred Hutchinson examined the brains of 59 women after death. In 63 percent of them they found male DNA, almost certainly left behind by a son. The oldest of those women was 94, and the cells were still sitting there.
Around week four or five of pregnancy, before… pic.twitter.com/LjyhnZprVb
— Anish Moonka (@anishmoonka) August 23, 2026
Researchers found male DNA in brains of 63 percent of 59 women after death.
Oldest woman was 94 and still carried the cells.
Fetal cells enter mom’s blood around week 4-5 of pregnancy.
Found in liver lungs thyroid kidneys heart and skin.
In C-section scars they act like normal skin cells making collagen.
Mouse studies show they rush to heart injuries and become muscle.
Appear less often in some breast cancer patients.
Also turn up more in Hashimoto’s thyroid disease.
Grandmother cells can cross into the next generation too.