UCSF Researchers Map Maternal-Fetal Interface in Unprecedented Detail Identifying Risks for Preeclampsia and Cannabis Impact

UCSF scientists identify new cell types and biological links between cannabis use and pregnancy complications in a landmark single-cell study.

By: AXL Media

Published: Apr 8, 2026, 11:34 AM EDT

Source: Information for this report was sourced from EurekAlert!

Mapping the Complexity of Human Pregnancy

Scientists at UCSF have utilized advanced single-cell and spatial tools to create the most detailed map to date of the maternal-fetal interface, a temporary structure essential for fetal development. By analyzing approximately 200,000 individual cells and comparing them with 1 million cells in their original uterine positions, the team has provided a clearer picture of how this region supports pregnancy. Senior author Jingjing Li, PhD, notes that this work allows researchers to track cell development and see how specific cellular behaviors are linked to complications like preterm birth and miscarriage.

Identifying a Regulatory Gatekeeper Cell

The atlas revealed the existence of a previously unknown maternal cell type located at the point where fetal placental cells first enter the uterus. These cells appear to act as gatekeepers, regulating how deeply placental cells invade uterine tissue to establish vital blood flow to the fetus. According to the study published in Nature, this discovery is fundamental to understanding the mechanics of a healthy pregnancy, as the depth of invasion is a critical factor in the successful establishment of the maternal-fetal bond.

Biological Links Between Cannabis and Pregnancy Risk

A significant finding of the study involves the discovery that this new maternal cell type carries a cannabinoid receptor. When exposed to cannabinoid molecules, these cells further restricted the invasion of placental cells into the uterine tissue. First author Cheng Wang, PhD, suggests that this provides a biological basis for previous population studies that linked cannabis use during pregnancy to poorer health outcomes. This finding offers a cellular explanation for how external substances can directly interfere with the essential physical development of the placenta.