ObjectiveTo investigate the expression of amniotic fluid levels and blood serum levels of matrix metalloproteinases-8 (MMP-8) and interleukin-6 (IL-6) in women with preterm delivery. MethodsBetween January 2010 and December 2012, we collected the amniotic fluid of 102 preterm pregnant women and 98 full term pregnant women and analyzed the MMP-8 levels and IL-6 levels in amniotic fluid and blood serum. Meanwhile, we also collected the amniotic fluid to do bacterial culture. ResultsThe amniotic fluid levels of MMP-8 in preterm pregnant women were higher than those in full term pregnant women [(320.45±59.88) vs (153.72±29.12) ng/mL, P<0.05], but there was no obvious discrepancy in the blood serum levels of MMP-8 in the two groups [(9.56±2.11) vs (9.42±2.01) ng/mL, P>0.05]. Both amniotic fluid levels and blood serum levels of IL-6 in preterm pregnant women were significantly higher than the full term pregnant women [(90.5±16.3] vs (20.6±12.5) μg/L, P<0.05; (159.2±20.4) vs (22.3±11.8) μg/L, P<0.05]. The positive bacterial culture rate of preterm pregnant women was higher than the full term pregnant women (8.8% vs 1.0%, P<0.05). ConclusionInfection is the most important reason for preterm pregnancy. MMP-8 level increases in the amniotic fluid, and the level of IL-6 in amniotic fluid and blood serum is a valuable clinical index for identifying premature delivery.
ObjectivesTo systematically review the association between pregnancy-induced hypertension (PIH) and preterm birth in mainland China.MethodsPubMed, The Cochrane Library, ScienceDirect, Web of Science, CBM, CNKI, WanFang Data and VIP databases were electronically searched to collect studies on the association between PIH and preterm birth in mainland China from January, 2007 to March, 2019. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies; then, meta-analysis was performed by using Stata 12.0 software.ResultsA total of 48 studies were included, involving 43 276 cases of premature birth, 527 995 cases of full-term control group, in which there were 3 446 cases of PIH in premature delivery, with a prevalence rate of 7.96%. There were 14 099 cases of PIH in the full-term control group, with a prevalence rate of 2.67%. The results of meta-analysis showed that PIH was associated with preterm birth (OR=3.27, 95%CI 2.64 to 4.05, P<0.001). The overall population attributable risk was 13.0%. Subgroup analysis was conducted for different study types, and the results were unaltered.ConclusionsThe current evidence shows that PIH is associated with preterm birth. During pregnancy, the management and intervention of pregnant females with gestational hypertension should be strengthened, and active treatment should be supervised to prevent the occurrence of premature birth.