This 2023 rodent study found that effects of stress during mid-late gestation were epigenetically transmitted to the first, second, and third female generations:

“We investigated effects of gestational chronic variable stress (CVS) in rats using restraint and social isolation stress in the parental F₀ generation. Only the F₀ pregnant dams were subjected to stress.

When a pregnant female experiences adversity, impacts of that stress affect exposed somatic tissues (F₀ generation), the fetuses (F₁ generation), and the fetuses’ germline (F₂ generation). A true transgenerational inheritance arises when germline epimutations are transmitted to unexposed F₃ offspring.

A subset of F₁ rats was housed in an enriched environment (EE) to mitigate adverse effects of CVS. F₂ offspring reared in EE had increased birth weights, but their uterine gene expression patterns remained comparable to those of stressed animals.

We provide evidence that psychological and psychosocial CVS alters inflammatory status and endocrine markers in uteri of adult dams through transgenerational programming of the female germline. EE therapy in prenatally stressed F₁ offspring had no beneficial effects on uterine expression of inflammatory and endocrine markers for them or their future offspring.”

https://www.mdpi.com/1422-0067/24/4/3734 “Environmental Enrichment Promotes Transgenerational Programming of Uterine Inflammatory and Stress Markers Comparable to Gestational Chronic Variable Stress”