Related Experiment Videos
Mechanisms underlying "functional" progesterone withdrawal at parturition.
Amy G Brown1, Rita S Leite, Jerome F Strauss
1III 1354 Biomedical Research Building II/III, 421 Curie Boulevard, Philadelphia, PA 19104, USA.
Annals of the New York Academy of Sciences
|February 26, 2005
Summary
Progesterone withdrawal is key for labor initiation in most species. In humans, elevated progesterone suggests a "functional" withdrawal, but the specific genes affected remain unknown.
Area of Science:
- Reproductive biology
- Molecular endocrinology
- Pregnancy research
Background:
- Progesterone is crucial for maintaining uterine quiescence during pregnancy.
- Progesterone withdrawal typically precedes labor initiation in most species.
- Human pregnancy maintains high progesterone levels until birth, suggesting a functional withdrawal.
Purpose of the Study:
- To explore the mechanisms behind functional progesterone withdrawal in human pregnancy.
- To identify specific uterine genes regulated by progesterone withdrawal at term.
Main Methods:
- Review of existing literature on progesterone's role in pregnancy and labor.
- Analysis of proposed mechanisms for decreased uterine progesterone sensitivity.
- Focus on progesterone receptor (PR) regulation and downstream gene expression.
Main Results:
- Circulating progesterone remains high in humans until birth.
- Functional progesterone withdrawal is proposed, involving mechanisms like progesterone catabolism, altered PR isoforms, cofactor changes, and inflammation-induced PR repression.
- Specific target genes of PR in the human uterus at term are not yet identified.
Conclusions:
- Functional progesterone withdrawal, not a decline in circulating levels, likely enables human labor.
- Understanding these mechanisms is vital for managing preterm labor and term birth.
- Further research is needed to pinpoint the specific genes transcriptionally regulated by PR during functional withdrawal.