Amniotic fluid soluble Toll-like receptor 2 in pregnancies complicated by preterm prelabor rupture of membranes

Objective: To determine amniotic fluid soluble Toll-like receptor 2 (sTLR2) levels in PPROM according to the presence of microbial invasion of the amniotic cavity (MIAC), histological chorioamnionitis (HCA), and both these conditions. To test the cutoff level of 222.7?ng/mL, as proposed in our previous study, in order to distinguish women with both MIAC and HCA. Methods: 169 women with a gestational age between 24+0 and 36+6 weeks were included in a prospective cohort study. Amniocenteses were performed, and sTLR2 in the amniotic fluid were determined using ELISA. Results: Women with MIAC had higher sTLR2 levels (median 113.2?ng/mL) than those without MIAC (median 47.1 ng/mL; p < 0.0001). Women with HCA did not have a higher sTLR2 level (median 52.6?ng/mL) compared with women without HCA (median 47.1?ng/mL; p = 0.23). Women with both MIAC and HCA had higher sTLR2 levels (median: 311.3?ng/mL) than other women (17.5?ng/mL; p < 0.0001). The cutoff level 222.7?ng/mL had a sensitivity of 63%, a specificity of 98%, and a likelihood ratio of 40.3 for the prediction of both MIAC and HCA. Conclusions: Amniotic fluid sTLR2 is a promising predictor of both MIAC and HCA with high specificity in PPROM.     

Amniotic fluid soluble Toll-like receptor 4 in pregnancies complicated by preterm prelabor rupture of the membranes

Objective: To determine amniotic fluid soluble Toll-like receptor 4 (sTLR4) levels in women with preterm prelabor rupture of the membranes according to the presence of microbial invasion of the amniotic cavity and histological chorioamnionitis and its relation to neonatal outcome. Methods: One hundred two women with singleton pregnancies with a gestational age between 24?+?0 and 36?+?6 weeks were included in a prospective cohort study. Amniocenteses were performed, and the concentrations of sTLR4 in the amniotic fluid were determined using sandwich enzyme-linked immunosorbent assay technique. Results: Women with the presence of microbial invasion of the amniotic cavity had higher sTLR4 levels [median 54.2?ng/mL, interquartile range (IQR) 10.15–289.9] than those without this condition (median 18.1?ng/mL, IQR 8.1–29.9; p?=?0.001). Women with the presence of histological chorioamnionitis had a higher sTLR4 level (median 28.0?ng/mL, IQR 11.15–178.1) compared with women without histological chorioamnionitis (median 13.0?ng/mL, IQR 7.8–28.7; p?=?0.003). A mixed linear model was used to adjust for confounders. The difference was found only between women with and without microbial invasion of the amniotic cavity in this model. Conclusions: Microbial invasion of the amniotic cavity was associated with higher amniotic fluid sTLR4 levels independent of confounders.     

Vaginal fluid IL-6 and IL-8 levels in pregnancies complicated by preterm prelabor membrane ruptures

Objective: To determine the vaginal fluid interleukin (IL)-6 and IL-8 concentrations in pregnancies complicated by preterm prelabor rupture of membranes and their correlation to microbial invasion of the amniotic cavity (MIAC) as well as histological chorioamnionitis (HCA).

Methods: Sixty-eight women with singleton pregnancies were included in this study. Vaginal fluid was collected at the time of admission. IL-6 and IL-8 concentrations in the vaginal fluid were determined using ELISA.

Result: Women with MIAC had higher vaginal fluid IL-6 levels compared to those without MIAC (with MIAC: median 374?pg/mL versus without MIAC: median 174?pg/mL; p?=?0.03). IL-8 levels were higher in women with MIAC only in the crude analysis but not after adjustment for gestational age. There was no difference in the IL-6 and IL-8 concentrations between those with and without HCA. Women with both MIAC and HCA had higher IL-6 vaginal fluid levels than those without both MIAC and HCA (with MIAC and HCA: median 466?pg/mL versus without MIAC and HCA: median 178?pg/mL; p?=?0.02). IL-8 levels were higher in women with MIAC and HCA only in the crude analysis but not after adjustment for gestational age.

Conclusions: Vaginal fluid IL-6 but not IL-8 levels reflect the presence of MIAC and both MIAC and HCA.     

Umbilical cord blood markers of oxidative stress in pregnancies complicated by preterm prelabor rupture of membranes

Objective: To determine umbilical cord blood total antioxidant capacity (TAC), ferric reducing antioxidant power (FRAP), thiobarbituric acid-reacting substances (TBARS), advanced glycation end products (AGEs) and markers of oxidative stress in pregnancies complicated by preterm prelabor rupture of membranes (PPROM) and their associations with microbial invasion of the amniotic cavity (MIAC) and/or histological chorioamnionitis (HCA), funisitis and selected aspects of short-term neonatal morbidity.

Materials and methods: One hundred and sixty-five women with singleton pregnancies complicated by PPROM were included in this study. Blood samples were obtained by venipuncture from the umbilical cord vein after the delivery of the newborn. The umbilical cord blood concentrations of TAC, FRAP, TBARS and AGEs were measured.

Results: The presence of MIAC, HCA and funisitis did not show differences in the umbilical cord blood TAC, FRAP, TBARS and AGEs concentrations. Positive correlations were found between the gestational age at sampling and umbilical cord blood TAC and AGEs concentrations (TAC: rho?=?0.26; p?=?0.001; AGEs: rho?=?0.35; p?<?0.0001). There was no association between umbilical cord blood TAC, FRAP, TBARS and AGEs concentrations and selected aspects of short-term neonatal morbidity.

Conclusions: Oxidative stress is associated with PPROM, as indicated by the presence of markers tested in the umbilical cord blood; however, the evaluated oxidative stress markers are not influenced by the presence of MIAC and/or HCA, and funisitis or subsequent development of selected aspects of short-term neonatal morbidity.     

Microbial invasion and histological chorioamnionitis upregulate neutrophil-gelatinase associated lipocalin in preterm prelabor rupture of membranes

Our recent exploratory proteomic study suggested increased levels of neutrophil-gelatinase associated lipocalin (P80188, NGAL_HUMAN) due to microbial invasion of the amniotic cavity (MIAC) and histological chorioamnionitis (HCA) in women with preterm prelabor rupture of the membranes. In this study, we verified the proteomics findings by assessing the amniotic fluid NGAL by ELISA in the original exploratory cohort. The NGAL level was significantly higher in women positive for both MIAC and HCA compared to women with both conditions ruled out (median 75.1?ng/ml versus 27.9?ng/ml; p?<?0.0001). For independent validation and to assess NGALs potential to stratify women positive for both MIAC and HCA from women in whom at least one of these conditions was absent, we subsequently designed a retrospective replication cohort. Significantly higher NGAL levels were found in women positive for both MIAC and HCA (median 65.9?ng/ml versus 34.2?ng/ml; p?=?0.0061). Significantly higher levels of NGAL were confirmed only in strata below 32 weeks of gestation. Based on the observed likelihood ratio, the best predictive cutoff level (47.1?ng/ml) was evaluated in both cohorts. Data from the verification cohort implied that NGAL is a valuable clinical marker for revealing MIAC leading to HCA; however, this potential was not replicated in the replication cohort.     

Neonatal outcomes in subgroups of women with preterm prelabor rupture of membranes before 34 weeks

Objective: To evaluate the influence of microbial invasion of the amniotic cavity (MIAC) and histological chorioamnionitis (HCA) on short-term neonatal outcome in women with preterm prelabor rupture of membranes before 34 weeks of gestation.

Methods: A prospective observational cohort study including 122 pregnant women with PPROM between 24+0 and 34+0. MIAC was defined as a positive PCR result for Ureaplasma species, Mycoplasma hominis and Chlamydia trachomatis and/or positive PCR result for the 16S rRNA gene in the amniotic fluid. HCA was defined according to the Salafia classification. Maternal and short-term neonatal outcomes were evaluated according to the presence or absence of MIAC and/or HCA.

Results: The presence of both MIAC and HCA was observed in 36% (45/122) of women, HCA alone in 34% (41/122) and MIAC in 5% (6/122). A significantly higher incidence of early onset sepsis was observed in newborns born from women with both MIAC and HCA [33% (15/45)] compared with women with HCA alone [12% (5/41)] or MIAC alone [0% (0/6)] or women without MIAC or HCA detected [0% (0/30); p?=?0.001].

Conclusions: The presence of both MIAC and HCA increases the risk of early onset sepsis in pregnancies complicated by preterm prelabor rupture of membranes before 34 weeks of gestation.     

Microbial load of umbilical cord blood Ureaplasma species and Mycoplasma hominis in preterm prelabor rupture of membranes

Abstract

Objective: To evaluate Ureaplasma species and M. hominis DNA in the umbilical cord blood and its correlation with its microbial load in the amniotic fluid, as a measure of microbial burden in fetal inflammatory response and neonatal outcome in pregnancies complicated by preterm prelabor rupture of membranes (pPROM).

Study design: A retrospective study of 158 women with singleton pregnancies complicated by pPROM between 24^0/7 and 36^6/7 weeks was conducted. Amniotic fluid was obtained from all women by transabdominal amniocentesis, and umbilical cord blood was obtained by venipuncture from umbilical cords immediately after the delivery of the neonates. The Ureaplasma species and M. hominis DNA was quantitated using absolute quantification techniques.

Result: Ureaplasma species and M. hominis DNA was identified in 9% of the umbilical cord blood samples. No correlation between the amniotic fluid and umbilical cord blood microbial load was observed. The presence of Ureaplasma species and M. hominis DNA in the umbilical cord blood had no impact on short-term neonatal morbidity.

Conclusions: A high microbial load of genital mycoplasma Ureaplasma species DNA in the umbilical cord in pregnancies complicated by pPROM is not associated with a high fetal inflammatory response and is therefore not associated with serious neonatal morbidity.     

Cervical fluid calreticulin and cathepsin-G in pregnancies complicated by preterm prelabor rupture of membranes

Objective: The study aimed to determine the cervical calreticulin and cathepsin-G concentrations in pregnancies complicated by preterm prelabor rupture of membranes (PPROM) with respect to the presence of microbial invasion of the amniotic cavity (MIAC) and intra-amniotic inflammation (IAI).

Methods: Eighty women with singleton pregnancies complicated by PPROM were included in this study. Cervical and amniotic fluids were obtained at the time of admission, and concentrations of calreticulin and cathepsin-G in cervical fluid were determined using ELISA. The MIAC was defined as a positive PCR analysis for Ureaplasma species, Mycoplasma hominis, and/or Chlamydia trachomatis and/or by positivity for the 16S rRNA gene. IAI was defined as amniotic fluid bedside IL-6 concentrations ≥745?pg/mL

Result: Neither women with MIAC nor with IAI had different cervical fluid concentrations of calreticulin (with MIAC: median 18.9?pg/mL vs. without MIAC: median 14.7?pg/mL, p?=?0.28; with IAI: median 14.3?pg/mL vs. without IAI: median 15.6?pg/mL, p?=?0.57;) or of cathepsin-G (with MIAC: median 30.7?pg/mL vs. without MIAC: median 24.7?pg/mL, p?=?0.28; with IAI: median 27.3?pg/mL vs. without IAI: median 25.1?pg/mL, p?=?0.80) than women without those complications. No associations between amniotic fluid IL-6 concentrations, gestational age at sampling, and cervical fluid calreticulin and cathepsin-G concentrations were found.

Conclusions: Cervical fluid calreticulin and cathepsin-G concentrations did not reflect the presence of MIAC or IAI in women with PPROM.     

Cervical fluid interleukin 6 and intra-amniotic complications of preterm prelabor rupture of membranes

Objective: To determine if cervical fluid interleukin (IL)-6 concentrations in women with preterm prelabor rupture of membranes (PPROM) allows identification of microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation (IAI).

Methods: One hundred forty-four women with singleton pregnancies complicated by PPROM were included in this prospective cohort study. Cervical and amniotic fluids were collected at the time of admission and concentrations of IL-6 were measured using an ELISA and point-of-care test, respectively. Cervical fluid was obtained using a Dacron polyester swab and amniotic fluid was obtained by transabdominal amniocentesis. MIAC was diagnosed based on a positive PCR result for Ureaplasma species, M. hominis, and/or C. trachomatis and/or by positivity for the 16?S rRNA gene. IAI was defined as amniotic fluid point-of-care IL-6 concentrations ≥745?pg/mL. The women were assigned to four subgroups based on the presence of MIAC and/or IAI: microbial-associated IAI (both MIAC and IAI), sterile IAI (IAI alone), MIAC alone, and without either MIAC or IAI.

Results: (1) Women with microbial-associated IAI had higher cervical fluid IL-6 concentrations (median 560?pg/mL) than did women with sterile IAI (median 303?pg/mL; p?=?.001), women with MIAC alone (median 135?pg/mL; p?=?.0004), and women without MIAC and IAI (median 180?pg/mL; p?=?.0001). (2) No differences were found in cervical fluid IL-6 concentrations among women with sterile IAI, with MIAC alone, and without MIAC and IAI. (3) A positive correlation was observed between cervical fluid IL-6 concentrations and the amount of Ureaplasma species in amniotic fluid (copies DNA/mL; rho?=?0.57, p?p?Conclusions: The presence of microbial-associated IAI is associated with the highest cervical fluid IL-6 concentrations. Cervical IL-6 can be helpful in the identification of microbial-associated IAI.     

Streptococcus agalactiae in pregnancies complicated by preterm prelabor rupture of membranes

Objective: The main aim of this study was to evaluate the presence of Streptococcus agalactiae (S. agalactiae) in the vagina and the amniotic fluid in pregnancies complicated by preterm prelabor rupture of membranes (PPROM). The next aim was to evaluate the incidence of S. agalactiae early onset sepsis in newborns from PPROM pregnancies, with respect to the presence of S. agalactiae in the vagina and the amniotic fluid.

Methods: Singleton gestations with PPROM between 24?+?0 and 36?+?6 were included. A vaginal swab was obtained, and amniocentesis was performed at admission. The presence of S. agalactiae in the vagina and in the amniotic fluid was assessed by culture and by real-time polymerase chain reaction, respectively.

Results: In total, 336 women were included. The presence of S. agalactiae in the vaginal and amniotic fluid was found in 9% (31/336) and 1% (3/336) of women. One woman had S. agalactiae in the amniotic fluid but was negative for the presence of S. agalactiae in the vaginal fluid. Early onset neonatal sepsis developed in one newborn from pregnancies complicated by the presence of S. agalactiae in the amniotic fluid.

Conclusion: The presence of S. agalactiae in the vagina and amniotic fluid complicated approximately each 10th and each 100th PPROM pregnancy. Cultivation-negative findings of S. agalactiae in the vagina did not exclude the positivity of the amniotic fluid for S. agalactiae and the development of early onset sepsis in newborns.     

Periodontal disease and intra-amniotic complications in women with preterm prelabor rupture of membranes

Objective: Periodontal disease is frequently suggested as a possible causal factor for preterm delivery. The link between periodontal disease and preterm delivery is a possible translocation of periopathogenic bacteria to the placenta and amniotic fluid as well as a systemic response to this chronic inflammatory disease. However, there is a lack of information on whether there is an association between clinical periodontal status in women with preterm prelabor rupture of membranes (PPROM) and the presence of microbial invasion of the amniotic cavity (MIAC) and intra-amniotic inflammation (IAI). Therefore, the main aim of this study was to evaluate the incidence and severity of periodontal disease in women with PPROM. The secondary aim was to characterize an association between periodontal status and the presence of intra-amniotic PPROM complications (MIAC and/or IAI).

Materials and methods: Seventy-eight women with PPROM at gestational ages between 24?+?0 and 36?+?6 weeks were included in this study. The samples of amniotic fluid were obtained at admission via transabdominal amniocentesis, and amniotic fluid interleukin (IL)-6 concentrations were determined using a point-of-care test. All women had a full-mouth recording to determine the periodontal and oral hygiene status. Probing pocket depth and clinical attachment loss were measured at four sites on each fully erupted tooth.

Results: In total, 45% (35/78) of women with PPROM had periodontal disease. Mild, moderate, and severe periodontal disease was present in 19% (15/78), 19% (15/78), and 6% (5/78) of women, respectively. The presence of MIAC and IAI was found in 28% (22/78) and 26% (20/78) of women, respectively. Periopathogenic bacteria (2?×?Streptococcus intermedius and 1?×?Fusobacterium nucleatum) was found in the amniotic fluid of 4% (3/78) of women. There were no differences in periodontal status between women with MIAC and/or IAI and women without these intra-amniotic complications.

Conclusions: The presence of MIAC and IAI was not related to the periodontal status of women with PPROM.     

A point of care test for interleukin-6 in amniotic fluid in preterm prelabor rupture of membranes: a step toward the early treatment of acute intra-amniotic inflammation/infection

Objective: Preterm prelabor rupture of membranes (preterm PROM) accounts for 30–40% of spontaneous preterm deliveries and thus is a major contributor to perinatal morbidity and mortality. An amniotic fluid (AF) interleukin-6 (IL-6) concentration is a key cytokine for the identification of intra-amniotic inflammation, patients at risk of impending preterm delivery and adverse pregnancy complications. The conventional method to determine IL-6 concentrations in AF is an enzyme-linked immunosorbent assay (ELISA). However, this technique is not available in clinical settings, and the results may take several days. A lateral flow-based immunoassay, or point of care (POC) test, has been developed to address this issue. The objective of this study was to compare the performance of AF IL-6 determined by the POC test to that determined by ELISA for the identification of intra-amniotic inflammation in patients with preterm PROM.

Materials and methods: This retrospective cohort study includes 56 women with singleton pregnancies who presented with preterm PROM. Amniocentesis was performed at the time of diagnosis, and AF was analyzed using cultivation techniques for aerobic and anaerobic bacteria as well as genital mycoplasmas. AF Gram stain and AF white blood cell counts were determined. AF IL-6 concentrations were measured using both lateral flow-based immunoassay and ELISA. The primary outcome was intra-amniotic inflammation defined as AF ELISA IL-6?≥?2600?pg/ml. A previously determined cut-off of 745?pg/ml was used to define a positive POC test.

Results: (1) The POC test for AF IL-6 concentrations had 97% sensitivity and 96% specificity for the identification of intra-amniotic inflammation, as defined using ELISA among patients with preterm PROM and (2) the diagnostic performance of the POC test for IL-6 was strongly correlated to that of an ELISA test for the identification of intra-amniotic inflammation and was equivalent for the identification of acute inflammatory placental lesions and microbial invasion of the amniotic cavity (MIAC).

Conclusion: A POC AF IL-6 test can identify intra-amniotic inflammation in patients with preterm PROM. Results can be available within 20?min – this makes it possible to implement interventions designed to treat intra-amniotic inflammation and improve pregnancy outcomes.     

Evidence in support of a role for anti-angiogenic factors in preterm prelabor rupture of membranes

Objective.?Vaginal bleeding, placental abruption, and defective placentation are frequently observed in patients with preterm prelabor rupture of membranes (PROM). Recently, a role of vascular endothelial growth factor (VEGF) and its receptor, VEGF receptor (VEGFR)- 1 has been implicated in the mechanisms of membrane rupture. The purpose of this study was to determine whether the soluble form of VEGFR-1 and -2 concentrations in amniotic fluid (AF) change with preterm PROM, intra-amniotic infection/inflammation (IAI), or parturition.

Study design.?This cross-sectional study included 544 patients in the following groups: (1) midtrimester (MT) (n?=?48); (2) preterm labor (PTL) leading to term delivery (n?=?143); (3) PTL resulting in preterm delivery with (n?=?72) and without IAI (n?=?100); (4) preterm PROM with (n?=?46) and without IAI (n?=?42); (5) term in labor (n?=?48); and (6) term not in labor (n?=?45). The concentrations of sVEGFR-1 and sVEGFR-2 were determined by ELISA. Non-parametric statistics and logistic regression analysis were applied.

Results.?(1) Preterm PROM (with and without IAI) had a lower median AF concentration of sVEGFR-1 than patients with PTL who delivered at term (p?<?0.001 for each comparison); (2) A decrease in AFsVEGFR-1 concentrations per each quartile was associated with PROM after adjusting for confounders (OR 1.8; 95%CI 1.4–2.3); (3) IAI, regardless of the membrane status, was not associated with a change in the median AF concentrations of sVEGFR-1 and sVEGFR-2 (p?>?0.05 for each comparison); and (4) Spontaneous term and PTL did not change the median sVEGFR-1 and sVEGFR-2 concentrations (p?>?0.05 for each comparison).

Conclusion.?(1) This is the first evidence that preterm PROM is associated with a lower AF concentration of sVEGFR-1 than patients with PTL intact membranes. These findings cannot be attributed to gestational age, labor, or IAI; and (2) AF concentrations of sVEGFR-2 did not change with preterm PROM, IAI, or labor at term and preterm.     

Amniotic fluid cathepsin-G in pregnancies complicated by the preterm prelabor rupture of membranes

Objective: The aim of this study was to evaluate the amniotic fluid cathepsin-G concentrations in women with preterm prelabor rupture of membranes (PPROM) based on the presence of the microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation (IAI).

Methods: A total of 154 women with singleton pregnancies complicated by PPROM were included in this study. Amniotic fluid samples were obtained by transabdominal amniocentesis. Amniotic fluid cathepsin-G concentrations were assessed by ELISA. MIAC was determined using a non-cultivation approach. IAI was defined as an amniotic fluid bedside interleukin-6 concentration?≥?745?pg/mL.

Results: Women with MIAC had higher amniotic fluid cathepsin-G concentrations than women without MIAC (with MIAC: median 82.7?ng/mL, versus without MIAC: median 64.7?ng/mL; p?=?0.0003). Women with IAI had higher amniotic fluid cathepsin-G concentrations than women without this complication (with IAI: median 103.0?ng/mL, versus without IAI: median 66.2?ng/mL; p?p?Conclusions: The presence of either microbial-associated or sterile IAI was associated with increased amniotic fluid cathepsin-G concentrations in pregnancies complicated by PPROM. Amniotic fluid cathepsin-G appears to be a potential marker of IAI.     

Amniotic fluid calreticulin in pregnancies complicated by the preterm prelabor rupture of membranes

Objective: This study aimed to determine the amniotic fluid calreticulin concentrations in women with the preterm prelabor rupture of membranes (PPROM) based on the microbial invasion of the amniotic cavity (MIAC), intraamniotic inflammation (IAI) and microbial-associated IAI.

Methods: One hundred sixty-eight women with singleton pregnancies were included in this study. Amniotic fluid samples were obtained by transabdominal amniocentesis and were assayed for calreticulin concentrations by ELISA. IAI was defined as an amniotic fluid interleukin-6 concentration?>?745?pg/ml. Microbial-associated IAI was defined as the presence of both MIAC and IAI.

Result: Women with MIAC (with MIAC: median 54.4?ng/ml, versus without MIAC: median 32.6?ng/ml; p?<?0.0001), IAI (with IAI: median 66.8?ng/ml, versus without IAI: median 33.0?ng/ml; p?<?0.0001) and microbial-associated IAI (with microbial-associated IAI: median 82.5?ng/ml, versus without microbial-associated IAI: median 33.7?ng/ml; p?<?0.0001) had higher concentrations of calreticulin than women without these complications. An amniotic fluid calreticulin concentration of 81.4?ng/ml was found to be the best cutoff point for identifying women with microbial-associated IAI.

Conclusions: The presence of microbial-associated IAI is associated with increased amniotic fluid calreticulin concentrations. Calreticulin seems to be a promising marker for the early identification of PPROM complicated by microbial-associated IAI.     

Amniotic fluid clusterin in pregnancies complicated by the preterm prelabor rupture of membranes

Objective: The aim of this study was to evaluate clusterin concentrations in amniotic fluid in pregnancies complicated by preterm prelabor rupture of membranes (PPROM) with respect to the presence of the microbial invasion of the amniotic cavity (MIAC), intra-amniotic inflammation (IAI) and microbial-associated IAI.

Methods: One hundred thirty-six women with singleton pregnancies complicated by PPROM were included in this study. Amniotic fluid samples were obtained by transabdominal amniocentesis. Amniotic fluid clusterin concentrations were assessed by enzyme-linked immunosorbent assay. MIAC was determined by a non-cultivation approach. IAI was defined as an amniotic fluid bedside interleukin-6 concentration?≥745?pg/mL. Microbial-associated IAI was characterized as the presence of both MIAC and IAI.

Result: Women with MIAC, IAI and microbial-associated IAI had lower amniotic fluid clusterin concentrations than women without these complications (with MIAC: median 1314?ng/mL versus without MIAC: median 1633?ng/mL, p?=?0.003; with IAI: median 1281?ng/mL versus without IAI: median 1575?ng/mL, p?=?0.04; with microbial associated-IAI: median 1220?ng/mL versus without microbial-associated IAI: median 1575?pg/mL; p?=?0.008). A week negative correlation between amniotic fluid clusterin concentrations and gestational age at sampling was revealed (rho=??0.30; p?=?0.0005).

Conclusions: The presence of MIAC, IAI and microbial-associated IAI was characterized by lower amniotic fluid clusterin concentrations in pregnancies complicated by PPROM.     

Amniotic fluid markers of oxidative stress in pregnancies complicated by preterm prelabor rupture of membranes

Objective: To determine amniotic fluid total antioxidant capacity (TAC), ferric-reducing antioxidant power (FRAP) and thiobarbituric acid-reacting substances (TBARS), markers of oxidative stress, in pregnancies complicated by preterm prelabor rupture of membranes (pPROM) and their correlation to microbial invasion of the amniotic cavity (MIAC) and/or histological chorioamnionitis (HCA).

Methods: One-hundred thirty-eight women with singleton pregnancies complicated by pPROM were included in this study. Amniotic fluid was collected by transabdominal amniocentesis at the time of admission and amniotic fluid concentrations of TAC, FRAP and TBARS were measured.

Result: The presence of MIAC and/or HCA did not show any significant differences in the amniotic fluid TAC, FRAP and TBARS concentrations. Positive correlations between gestational age at sampling and amniotic fluid TAC and FRAP concentrations were found (TAC: rho?=?0.32; p?=?0.0002; FRAP: rho?=?0.36; p?<?0.0001). A negative correlation between gestation age at sampling and amniotic fluid TBARS concentrations was identified (rho?=?–0.25; p?=?0.004).

Conclusions: Oxidative stress is associated with pPROM as indicated by the presence of markers tested in the amniotic fluid; however, oxidative stress markers tested are not influenced by the presence of MIAC or HCA.