The physiologic changes associated with normal pregnancy are aimed toward promoting optimal fetal growth and development. In the maternal compartment, these changes, e.g., an increase in cardiac output and expansion of blood volume, are directed toward compensating the maternal cardiovascular system for the subsequent growth and development of a new vascular bed, the placenta. Although the placental vascular bed does not appear to enlarge throughout pregnancy, its blood supply increases dramatically in normal gestation. Furthermore, there appears to be a functional maturation of the placenta as its blood supply increases, providing for optimal delivery and transfer of the respiratory gases and various nutrients. The mechanisms responsible for these changes remain unclear, but likely involve a number of steroid hormones, vasoactive peptides, and other as yet unidentified substances. An alteration in the provision of any of these substances likely will affect subsequent placental development and blood flow; therefore, studies directed toward identifying these substances and their role(s) will improve our understanding of the control of uteroplacental blood flow and the factors necessary for optimal fetal growth.
|Original language||English (US)|
|Number of pages||10|
|Journal||Seminars in Perinatology|
|State||Published - Jan 1984|
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health
- Obstetrics and Gynecology