Effect of oligohydramnios and intrauterine infection on fetal blood vessels and umbilical artery blood flows in patients with preterm premature rupture of membranes

Hong, Joon Seok; Park, Kyo Hoon; Kim, Hyun Jun; Han, Sang Hoon; Jeon, Yong Tark; Kim, Yong Beom; Suh, Chang Suk

Abstract

OBJECTIVE
The purpose of this study was to establish the effect of oligohydramnios and intrauterine infection on fetal and umbilical blood flows in patients with preterm premature rupture of membranes (PPROM).
METHODS
Pulsed-wave Doppler imaging was used to determine the pulsatility index (PI) in the fetal renal, descending aorta, middle cerebral and umbilical arteries in 62 patients with PPROM. Amniocentesis was performed in 38 patients with PPROM. Amniotic fluid was cultured for aerobic and anaerobic bacteria and for mycoplasma. The patients with PPROM were divided into two groups according to the presence (n=21) or absence (n=41) of oligohydramnios and the presence (n=14) or absence (n=24) of intrauterine infection. Oligohydramnios was defined as the largest single pocket that measured <2 cm in the vertical plane. Data was expressed as multiples of the median (MOM) adjusted for gestational age, and statistical analysis was conducted with nonparametric statistics.
RESULTS
1) Fetuses with the presence of oligohydramnios had significantly lower MOM of PI of the fetal renal artery and higher MOM of PI of the fetal descending aorta than those without this condition (MOM of PI of the fetal renal artery: median [range]; 0.030 [-0.532, 0.404] vs. 0.167 [-0.357, 2.81] p=0.03. MOM of PI of the fetal decending aorta: median [range]; 0.085 [-0.160, 0.470] vs. -0.120 [-0.587, 0.548] p=0.004). 2) There was a significantly negative relationship between the largest single vertical pocket and MOM of PI of the fetal descending aorta (r=-0.283, p=0.03). 3) There were no significant differences in the MOM of PI of the fetal middle cerebral artery and umbilical artery between the two groups of patients. 4) Amniotic fluid culture was positive in 37% (14/38). 5) There were no significant differences in the MOM of PI of the fetal middle cerebral, renal artery, descending aorta and umbilical arteries between patients with and without the intrauterine infection.
CONCLUSION
Blood flow of the fetal renal artery and descending aorta, but not the middle cerebral and umbilical arteries, were affected by oligohydramnios in patients with PPROM but intrauterine infection did not affect the blood flow of the fetal and umbilical arteries in fetuses with PPROM.