Tehran University Medical Journal

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Considering the incidence of meconium-stained amniotic fluid (MSAF) in newborns and its complications, and also based on indirect reports pointing out relationship between nucleated red blood cell (nRBC), as a marker of chronic hypoxia, and MSAF in term newborns, and in order to determine this relationship more accurately, this study was done on women with uncomplicated singleton term pregnancy that admitted for delivery at Shariati hospital in year 2000. After excluding confounding factors on nRBC, case group who includes infants with MSAF, and control group who have clear amniotic fluid were determined. Maternal age and parity, gestational age, birth weight, apgar score, neonatal out come, and FHR pattern as well as newborn hemoglobin values were evaluated. Venous cord blood was analyzed for nRBC counts per 100 WBC. Case and control groups were divided according to nRBC counts with cutoff point of 10 and then compared statistically. From the samples, 117 cases and 67 controls were evaluated. Maternal and neonatal factors were similar in two situations. Number of nRBC was 3.75±4.8 in control group and 12.04±11.7 in case group (P<0.01) and it was abnormal (>10) in 9 percent of newborns with clear fluid and 32 percent of MSAF (P<0.01). Cord blood nRBC count increased when meconium is passed intrauterine. This suggests that cases with MSAF may be at risk of chronic hypoxia. Cohort research is recommended to study the affect of delivery mode on the neonatal outcome in cases with MSAF and to evaluate the cause of fetal hypoxia in uncomplicated pregnancy with MSAF.

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Background: The aim of this study was to statistically evaluate the hypothesis that the presence of meconium-stained amniotic fluid is associated with postpartum maternal infection.
Methods: This prospective cohort study included 573 term pregnant women in labor, with no other medical problems, that underwent cesarean section for pregnancy termination. Women with prolonged active-phase labor, prolonged rupture of membranes, complicated cesarean section and pre-operative infections were excluded from this study.
The subjects were divided into two groups: 280 women with meconium-stained amniotic fluid (M group), and 293 women with clear amniotic fluid (C group). A comparison was done regarding postpartum fever, endometritis and wound infection between the two groups. Student's t-test and chi square test were used for data analysis, along with linear regression, with p<0.05 indicating significance.
Results: Among the 573 women, a total of 82 women (14%) had fever after cesarean 42 women from the M group, and 40 women from the C group (p= 0.3). Among the 82 women who had fever, 33 women had continuous fever, 6.5% in group M and 2.7% in group C (p<0.05, RR: 1.98, 95% CI 1.3-3.1). Among the 573 women, 4% developed endometritis 5% in group M and 2% in group C (p<0.05, RR: 2.3, 95%, CI 1.3-3.4). Similarly, among the 573 women, a total of 5 women (1%) developed wound infection, 1.7% in group M and 0.68% in group C (p=0.7).
Conclusion: Meconium-stained amniotic fluid is associated with increased postpartum infection independent of other risk factors for infection.