The Placenta: A Maternofetal Interface.
Level 5 - mechanism / opinion, no new human data
Narrative review describing placental biology and mechanisms without primary human data or systematic synthesis.
PubMed 37603428 · doi:10.1146/annurev-nutr-061121-085246
What was done
This narrative review describes the biological role of the placenta as the maternofetal interface. The authors outline the transition from first-trimester histiotrophic nutrition derived from uterine gland secretions to second-trimester hemotrophic nutrition delivered through maternal blood, while reviewing emerging omics approaches used to study placental function.
What was found
The abstract reports no empirical measurements or quantitative data. It conceptually summarizes how the placenta regulates nutrient delivery in response to alterations in maternal physiology, blood flow, and dynamic changes in fetal growth rates.
Why it matters
Understanding the regulatory mechanisms of placental nutrient transport helps clarify how maternofetal nutrient exchange influences fetal development and long-term offspring health.
Limits
As a narrative review, this paper presents no original clinical data, sample size, or systematic synthesis of evidence, and the abstract provides no quantitative metrics.
Cited by
- supports In the first trimester of pregnancy, the embryo receives nutrition from uterine milk secretions rather than the placenta.