Fetal plasma MMP-9 concentrations are elevated in preterm premature rupture of the membranes.
OBJECTIVE
The objective of this study was to determine whether the concentrations of matrix metalloproteinase-9 (MMP-9) in the fetal (fetal plasma and amniotic fluid) and maternal compartments (plasma) are different in patients presenting with preterm premature rupture of membranes (PROM) than in those with preterm labor and intact membranes.


METHODS
Fetal plasma MMP-9, interleukin-1beta (IL-1beta), IL-6, soluble tumor necrosis factor receptors 1 (sTNF-R1) and 2 (sTNF-R2) were measured in fetuses with preterm labor and intact membranes (n = 96) and preterm PROM (n = 43). The concentrations of analytes were determined with sensitive and specific immunoassays. A P value <.05 was considered significant.


RESULTS
(1) The median fetal plasma MMP-9 concentration was significantly higher in fetuses with preterm PROM than in those with preterm labor (P =.035). (2) In contrast, fetal plasma IL-1beta, sTNF-R1, and sTNF-R2 were significantly higher in patients with preterm labor than in those with preterm PROM (IL-1beta, P =.01; sTNF-R1, P =.003; and sTNF-R2, P =.02). (3) The median amniotic fluid concentration of MMP-9 was higher in patients with preterm PROM than in those with preterm labor (P <.001).


CONCLUSIONS
Fetuses with preterm PROM have increased concentrations of an enzyme (MMP-9) implicated in the mechanism of membrane rupture but lower concentrations of IL-1beta, sTNF-R1, and sTNF-R2 than fetuses with preterm labor and intact membranes. A role for the fetus in the genesis of preterm PROM deserves consideration.
Romero
Roberto
R
Perinatology Research Branch, National Institute of Child Health and Human Development, Wayne State University/Hutzel Hospital, Department of OB/GYN, Detroit, MI 48201, USA. warfiela@mail.nih.gov
Chaiworapongsa
Tinnakorn
T
Espinoza
Jimmy
J
Gomez
Ricardo
R
Yoon
Bo Hyun
BH
Edwin
Sam
S
Mazor
Moshe
M
Maymon
Eli
E
Berry
Stanley
S
D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000097:blood; D005260:Female; D005312:Fetal Blood; D005322:Premature Rupture of Fetal Membranes / Q000097:blood*; D006801:Humans; D007375:Interleukin-1 / Q000097:blood; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D007752:Obstetric Labor, Premature / Q000097:blood; D009994:Osmolar Concentration; D011247:Pregnancy; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D012995:Solubility
D015703:Antigens, CD; D007375:Interleukin-1; D018124:Receptors, Tumor Necrosis Factor; D047888:Receptors, Tumor Necrosis Factor, Type I; D047889:Receptors, Tumor Necrosis Factor, Type II; D020780:Matrix Metalloproteinase 9