Am J Perinatol 1992; 9(4): 275-278
DOI: 10.1055/s-2007-994788
ORIGINAL ARTICLE

© 1992 by Thieme Medical Publishers, Inc.

Atrial Natriuretic Factor Concentrations During Pregnancy and in the Postpartum Period

Christos G. Hatjis, Alexander D. Kofinas, James P. Greelish, Melissa Swain, James C. Rose
  • Division of Maternal-Fetal Medicine, Departments of Obstetrics and Gynecology and Physiology/Pharmacology, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina, and Division of Perinatology, Riverside Methodist Hospitals, Columbus, Ohio 43214
Further Information

Publication History

Publication Date:
04 March 2008 (online)

ABSTRACT

Atrial natriuretic factor (ANF) is a hormone that regulates fluid and electrolyte homeostasis. Increased intra-atrial pressure or atrial distention, which might occur secondary to intravascular volume expansion, stimulate the secretion of ANF by human atrial myocytes. During normal human pregnancy, there is a progressive increase in total intravascular fluid volume. Thus, we asked the following question: Does this physiologic adaptation to pregnancy result in an increase in ANF concentrations? Concentrations of α-human ANF (α-hANF) were measured by a specific radioimmunoassay in venous blood samples obtained longitudinally in the first, second, and third trimesters of pregnancy, during the intrapartum period, in the early postpartum period, and 6 to 8 weeks postpartum from 11 normal women who had no antepartum, intrapartum, or postpartum complications. Maternal circulating α-hANF levels were not different from those seen in the nonpregnant state. However, higher α-hANF concentrations were noted in the early postpartum period. Although the hypervolemia of normal pregnancy is not associated with higher α-hANF concentrations, other possibilities (such as increased ANF clearance, dilutional effects) need to be investigated. Finally, the etiology for the transient increase in α-hANF levels in the early postpartum period remains to be elucidated.