Association of the Gln27Glu polymorphism of the beta-2-adrenergic receptor with preterm labor.

OBJECTIVES: To investigate a potential association between the beta-2-adrenergic receptor (B2AR) polymorphisms occurring at amino acid positions 16 (Arg16Gly) and 27 (Gln27Glu) and preterm labor. METHODS: Eighty patients with preterm labor and 76 control subjects were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: A significant association was found between Gln27Glu substitution and preterm labor (P=0.001). The frequency of Gly16 and Glu27 alleles were found to be higher in patients than in control women (0.54 vs. 0.48 and 0.42 vs. 0.26, respectively), and the odds ratio for the occurrence of preterm labor was 2.14 (95% CI, 1.32-3.46; P=0.002) for the Glu 27 allele. An early delivery was noted in 52.5% of patients. CONCLUSION: The Gln27Glu polymorphism of the B2AR gene may have a role in molecular pathogenesis of preterm labor. Glu27 allele in patients with preterm labor might be a risk factor for deliveries before 37 weeks of gestation.     

Cytokine abundance in placental tissues: evidence of inflammatory activation in gestational membranes with term and preterm parturition

OBJECTIVES: This study of the changes in cytokine concentrations in gestational tissues from women with term and preterm labor was undertaken to assess the extent of inflammatory activation associated with spontaneous labor and delivery. STUDY DESIGN: Extracts of amniotic, chorionic-decidual, and placental tissues from women delivered at term before labor (n = 15), at term after labor (n = 15), and preterm (n = 31) were assayed for interleukin 1beta, interleukin 6, and interleukin 8. RESULTS: In amniotic tissues of women delivered by spontaneous labor at term the median interleukin-6, interleukin-8, and interleukin-1beta concentrations were 3.8 to 5.4 times those of tissues from women delivered at term without labor (P <.05, Mann-Whitney U test). Interleukin-6 and interleukin-8 concentrations were also significantly increased (3. 3-4 times) in chorionic-decidual tissues. Marked increases (approximately 3-6 times) in the concentrations of all 3 cytokines were observed in both amniotic and chorionic-decidual tissues from women with preterm deliveries with respect to those from women with term deliveries after labor. Cytokine concentrations were significantly correlated within amniotic tissues from both women with term delivery after labor and women with preterm delivery and also in preterm chorionic-decidual tissues but not preterm placental tissues. Concentrations of cytokines in the tissues of women delivered preterm were not significantly affected by mode of delivery, treatment with antibiotics, or twin birth. In preterm tissues with evidence of intrauterine infection only amniotic interleukin-1beta concentrations were significantly elevated (P <. 05). Little or no labor-related change in cytokine concentrations was seen within placental tissues. CONCLUSIONS: Increased cytokine abundance in gestational membranes associated with labor supports the view that an inflammatory process is involved in both term and preterm labor. This process does not, however, appear to be evident in the villous placenta.     

Beta2-adrenergic receptor gene polymorphisms and pregnancy outcome

AIMS: The association between alleles at two loci of the polymorphic beta2-adrenergic receptor (beta2AR) gene and pregnancy outcome was determined. METHODS: In a case-control study, buccal swabs obtained from 159 mother-infant pairs after a preterm or term birth were analyzed by gene amplification and endonuclease digestion for polymorphisms at codons 16 and 27 of the beta2AR gene. RESULTS: Homozygosity for allele A at codon 16 (Arg-16) occurred in 26 (20.5%) of 127 mothers with a term birth and in none of the mothers who had a spontaneous preterm birth (p=0.002). Conversely, 24 of 32 (75.0%) mothers with a spontaneous preterm birth, as compared to 58 of 127 (45.7%) mothers with term births, were Arg-16/ allele G (Gly-16) heterozygotes (p=0.003). There was no relation between pregnancy outcome and infant genotype at codon 16 or maternal or infant genotypes at codon 27. The alleles at codon 16 and 27 were in linkage disequilibrium and the combinations of Arg-16-Gln-27 homozygosity (p=0.04) and Arg-16/Gly-16-Gln homozygous (p=0.01) were associated with a decreased and increased rate of spontaneous preterm birth, respectively. CONCLUSION: At codon 16 of the beta2-AR gene, maternal Arg-16 homozygosity protects against, and Gly-16 predisposes to spontaneous preterm birth.     

Decreased serum level of macrophage inflammatory chemokine-3beta/CCL19 in preterm labor and delivery

OBJECTIVE: Chemokines are small soluble molecules which mediate leukocyte migration and may be involved in the pathophysiology of preterm labor. We aimed to determine if serum concentrations of selected chemokines are changed in preterm labor and delivery. STUDY DESIGN: A novel array-based enzyme-linked immunosorbent assay was used to quantitate serum levels of nine chemokines from a single sample: MDC/CCL22, TARC/CCL17, ITAC/CXCL11, I-309/CCL1, IP-10/CXCL10, MIP-1alpha/CCL3, -1beta/CCL4, -3alpha/CCL20 and -3beta/CCL19. Women in preterm labor who delivered (n = 17), women at preterm pregnancy not in labor (n = 13) and women in labor at term (n = 8) participated. RESULTS: In the preterm delivery group of patients, the MIP-3beta/CCL19 concentration was in mean (+/-S.D.) 70.4+/-31.7 pg/mL, which was significantly lower than that in preterm gravidas not in labor of 123+/-34 pg/mL (p < 0.001) and those in labor at term of 118+/-25.6 pg/mL (p < 0.01). The other measured chemokines did not differ significantly. CONCLUSIONS: Of a small number of examined chemokines, we were able to show that one of them, MIP-3beta/CCL19 was significantly lower in women with preterm labor and delivery. Whether or not this chemokine has a potential as biochemical marker of preterm delivery remains to be determined.     

阴道超声测量子宫颈长度及宫颈管宽度对预测早产的价值

目的　探讨阴道超声测量正常孕妇宫颈长度及宫颈管宽度对先兆早产孕妇发生早产的预测价值。方法　对无任何合并症和并发症的 1 54例正常单胎初产妇 ,于妊娠 1 6～ 35周经阴道超声测量宫颈长度和宫颈管宽度 ,记录宫颈内口有无开大。按孕周不同分成 5组 ,观察不同孕周组孕妇的宫颈变化。同时对 58例有先兆早产症状的孕妇进行宫颈长度及宫颈宽度的超声测量 ,并追踪其妊娠结局。结果　 (1 )正常单胎孕妇各不同孕周组间宫颈长度及宫颈管宽度无明显不同 ,宫颈长度平均为(36± 5)mm ,宫颈管宽度为 (4± 1 )mm ,均无宫颈内口开大。 (2 ) 58例先兆早产孕妇中发生早产的 1 1例为早产组 ,未发生早产的 47例为非早产组。两组孕妇年龄、孕次、出现先兆早产的孕周、保胎的方法及指检宫颈长度比较 ,差异均无显著性 (P >0 0 5)。以宫颈长度 > x - 2s(2 6mm)为界值 ,早产组孕妇的宫颈长度均≤ 2 6mm ,平均为 (1 8± 6)mm ,显著短于非早产组的 (32± 6)mm。两组比较 ,差异有极显著性 (P <0 0 0 1 )。 (3)以宫颈长度≤ 2 6mm为界值 ,预测先兆早产孕妇发生早产的敏感性为1 0 0 % ,特异性为 81 % ,阳性预测值为 55 % ,阴性预测值为 1 0 0 %。结论　经阴道超声检测宫颈长度 ,对先兆早产孕妇发生早产有一定的预测价值 ,先兆早     

Activity restriction and risk of preterm delivery*

Purpose: We sought to determine whether activity restriction (AR) in a cohort of women at high risk for preterm delivery is associated with the risk of preterm delivery.

Materials and methods: This is a secondary analysis of the Maternal-Fetal Medicine Units MFMU’s Preterm Prediction Study; a multicenter prospective cohort study designed to identify risk factors of preterm birth (PTB). The study group consisted of women with a singleton gestation that at their first study visit (23–24 weeks) had at least one of the following criteria: patient reported contractions, severe back pain, a cervical length <15?mm, spotting, protruding membranes, or positive fetal fibronectin. Women were assessed for AR at a 27- to 29-week study visit. Associations between AR and preterm delivery (<37 weeks) were examined through logistic regression models before and after adjustment for confounders.

Results: Of the 1086 women that met the inclusion criteria, 16.5% (n?=?179) delivered preterm. In this cohort, 9.7% (n?=?105) of women were recommended AR, with 37.1% (n?=?39) having a PTB. In the group not recommended AR (n?=?981), 14.3% (n?=?140) delivered preterm.

Conclusion: In this cohort of women at high risk for PTB, activity restriction was associated with an increased risk of PTB. The use of AR in this population should be discouraged.     

Course of maternal serum magnesium levels in low-risk gestations and in preterm labor and delivery

OBJECTIVES: To describe the course of total and ionized magnesium and total calcium levels in maternal serum during low-risk pregnancies and to compare women who developed preterm labor and delivery with those who delivered at term. METHODS: 209 women with low-risk pregnancies were enrolled in a prospective trial before the 18th week of gestation. No woman received oral magnesium supplementation. The ionized and total magnesium and total calcium levels in maternal serum were measured every 4-6 weeks. The data were grouped into 3 gestational periods (/=28 weeks of gestation) for overall comparison and analyzed with the general linear model for repeated measurements and ANOVA. p values of < 0.05 were considered statistically significant. RESULTS: 145 gestations were available for analysis. 27 women were hospitalized for preterm labor and in 16 of these preterm delivery occurred. Ionized and total magnesium and calcium levels were significantly lower after the 18th week of gestation than before. The cation levels in women with preterm labor and delivery did not differ from those with term delivery. CONCLUSION: Ionized and total magnesium and calcium levels decrease with increasing gestational age. Preterm labor and delivery do not seem to be related to changes in serum cation levels.     

Effect of parity and advanced maternal age on obstetric outcome.

OBJECTIVES: To examine the effect of parity on obstetric outcome in women aged 40 years or older. METHODS: A retrospective cohort of 16 427 singleton pregnancies delivered between 1998 and 2001 was studied. Obstetric outcomes in women aged 40 years or older versus women younger than 40 years were compared for both nulliparous and multiparous women. RESULTS: Of the 15 727 pregnancies (95.7%) that satisfied the inclusion criteria, 606 (3.9%) were in women aged 40 years or older. Advanced age was independently associated with cesarean delivery, birth and spontaneous preterm labor before 37 weeks, and low birth weight neonates in nulliparous women, but only with preterm birth before 37 weeks and cesarean delivery in multiparous women. CONCLUSION: Obstetric outcome in women aged 40 years or older was influenced by parity. Cesarean delivery and preterm birth before 37 weeks were independently associated with older age irrespective of parity. Advanced age is a risk factor for preterm birth.     

Association of polymorphisms in the beta2 and beta3 adrenoceptor gene with polycystic ovary syndrome

OBJECTIVE: To investigate polymorphisms of the beta2 and beta3 adrenoceptor (BAR-2 and BAR-3, respectively) genes associated with insulin-resistant polycystic ovary syndrome (PCOS) pathogenesis. STUDY DESIGN: Fifty-nine infertile Japanese women with PCOS and 97 healthy Japanese controls were studied. Blood metabolites and genomic DNA polymorphisms of BAR-2 (Arg16Gly and Gln27Glu) and BAR-3 (Trp64Arg) were analyzed. RESULTS: The PCOS group had significantly higher weight, body mass index, lipidemia and insulin resistance as compared to the control group. Glu 27 allele frequency in BAR-2 was significantly higher in PCOS patients as compared to the controls (0.07 vs 0.02, chi2 = 5.91, p = 0.02, OR 4.63, 95% CI 1.35-5.93), while Gly 16 allele frequency was only slightly higher in the PCOS group as compared to the controls (0.58 vs. 0.47, chi2 = 3.06, p = 0.08, OR 1.51, 95% CI 0.95-2.40). The Arg 64 allele frequency of BAR-3 was not significantly different between the 2 groups. Women with the Gly/Gly genotype for codon 16 or with either the Gln/Glu or Glu/Glu genotype for the codon 27 polymorphism of BAR-2 had significantly higher insulin resistance than those with the Arg/Arg and Gln/Gln genotypes. CONCLUSION: The polymorphism in codon 27 (Gln27Glu) of BAR-2 is linked to the expression of PCOS in Japanese women.     

A randomized multicenter study to determine the efficacy of activity restriction for preterm labor management in patients testing negative for fetal fibronectin.

OBJECTIVE: To assess the impact of activity restriction (AR) on the incidence of preterm birth in women treated for preterm labor testing negative for fetal fibronectin (fFN). STUDY DESIGN: Women who were diagnosed with preterm labor and tocolyzed with magnesium sulfate were concurrently screened with fFN for the purpose of subsequent management. Included were consenting patients with negative fFN, gestational age 23 0/7-33 6/7 weeks, cervical dilation < or =3 cm, and minimal vaginal bleeding. Patients were randomized to AR or no AR. Primary study outcome was incidence of preterm delivery and interval from randomization to delivery. RESULTS: A total of 73 women with negative fFN were randomized (36 with AR, 37 without AR). The overall preterm birth rate was 40%, with 44.4% of patients with AR and 35.1% of patients without AR delivering preterm, p=0.478. CONCLUSION: Maternal AR did not impact pregnancy outcome. The incidence of preterm birth in symptomatic women testing fFN negative was higher than previously reported.     

Anaphylatoxins in preterm and term labor

OBJECTIVE: The complement system plays a central role in the first line of defense against invading pathogens, and its activation involves the release of potent pro-inflammatory mediators such as anaphylatoxins C3a, C4a and C5a. The aim of this study was to determine whether differences existed in maternal plasma anaphylatoxin concentrations between patients with term and preterm parturition. STUDY DESIGN: A cross-sectional study was designed to determine the plasma anaphylatoxin concentrations in 296 pregnant women in the following groups: 1) normal pregnancy between 20-36 6/7 weeks (n=64); 2) term not in labor (n=70); 3) term in labor (n=60); and 4) preterm labor with intact membranes (n=102). Women with preterm labor were classified into: a) term delivery (n=24); b) preterm delivery without intra-amniotic infection (IAI) (n=62); and c) preterm delivery with IAI (n=16). Concentrations of C3a, C4a and C5a were determined by ELISAs. Statistical analysis was conducted with non-parametric methods. RESULTS: 1) The median plasma C5a concentration was lower in women at term in labor than in those not in labor (P<0.001). In contrast, there were no differences in plasma C3a and C4a concentrations between the two groups (P>0.05). 2) Among patients with preterm labor, those with IAI had a higher median plasma C5a concentration than those without IAI and those who delivered at term (post-hoc tests P<0.001 and P=0.01, respectively). When comparing the preterm labor subgroups with normal pregnancy, only women with preterm delivery and IAI had a median plasma C5a concentration higher than that of normal pregnant women (Kruskal-Wallis P<0.001, post hoc test P<0.001). There was no difference in the plasma C4a concentration among patients with preterm labor. The median plasma C3a concentration in patients with preterm labor with IAI was higher than in those without IAI (Kruskal-Wallis P=0.01, and post-hoc test P=0.005). There was no difference in the plasma C3a concentrations between women with preterm labor who delivered at term and those with preterm delivery, with or without IAI. In addition, no differences were observed in the median plasma C3a concentration between women with normal pregnancy and those in each of the preterm labor subgroups. CONCLUSIONS: The maternal plasma concentration of anaphylatoxin C5a is increased in women with preterm labor and IAI, but not in spontaneous labor at term.     

Cervical Ureaplasma urealyticum colonization might be associated with increased incidence of preterm delivery in pregnant women without prophlogistic microorganisms on routine examination

AIM: We examined whether the detection of Ureaplasma urealyticum DNA in the cervix is associated with preterm labor and delivery. METHODS: Eighty-two women (23 preterm labor cases and 59 controls) with no evidence of prophlogistic microorganisms on routine microbiologic examination were enrolled for this study. U. urealyticum colonization was examined using polymerase chain reaction of cervical swabs. RESULTS: The positivity rate of U. urealyticum DNA in preterm labor cases was significantly higher than that in the controls (87.0%vs 45.8%, P=0.0007). Women in the U. urealyticum-positive group more frequently delivered preterm compared with those in the negative group (36.2%vs 11.4%, P=0.0111). In five cases that delivered preterm with histologically confirmed chorioamnionitis, U. urealyticum DNA was detected in the placenta. CONCLUSIONS: Cervical U. urealyticum colonization might be associated with preterm labor and delivery.     

High levels of fetal cell-free DNA in maternal serum: a risk factor for spontaneous preterm delivery

OBJECTIVE: This study was conducted to determine whether there is a relationship between the concentration of fetal cell-free DNA in maternal serum and the duration of pregnancy in women who are at high risk for preterm delivery because of either preterm labor or preterm premature rupture of the membranes. STUDY DESIGN: Sera were collected and frozen from 71 women with a male fetus. Maternal serum fetal cell-free DNA concentration was measured with the use of real-time polymerase chain reaction amplification of DYS1. Fetal cell-free DNA concentrations were converted to multiples of the median. The following groups were studied: group 1: women with preterm labor and intact membranes who were delivered at > or = 36 weeks of gestation (n = 21); group 2: women with preterm labor who were delivered at <36 weeks of gestation (n = 29); and group 3: women with preterm premature rupture of the membranes in labor (n = 20) or not in labor (n = 1) who were delivered prematurely (<36 weeks of gestation). Kaplan-Meier and Cox regression analyses were used to analyze the relationship between fetal cell-free DNA concentrations and the likelihood of preterm delivery. RESULTS: A cut-off value for fetal cell-free DNA of 1.82 multiples of the median was chosen for analysis. The cumulative rate of early preterm delivery (<30 weeks of gestation) was significantly higher for women with fetal cell-free DNA concentrations of > or = 1.82 multiples of the median than those with fetal cell-free DNA concentrations below this cut-off (45% [95% CI, 36%-74%] vs 18% [95% CI, 11%-25%]; P = .008]. The cumulative rate of preterm delivery (<36 weeks of gestation) was also significantly higher at > or = 1.82 multiples of the median (73% [95% CI, 52%-93%] vs 66% [95% CI, 54%-79%]; P = .02). After adjustment for covariates, Cox analysis showed that fetal cell-free DNA at > or = 1.82 multiples of the mechanisms of disease that are associated with a mean hazard rate of delivery of 1.57 (P = .005). CONCLUSION: High concentrations of fetal cell-free DNA in maternal serum are associated with an increased risk of spontaneous preterm delivery. This observation may have implications for the understanding of the mechanisms of disease that is associated with preterm labor.     

Azurocidin levels in maternal serum in the first trimester can predict preterm prelabor rupture of membranes

Abstract

Objective: To determine the possible association between azurocidin in maternal serum in the first trimester of pregnancy and subsequent spontaneous preterm labor, preterm prelabor rupture of membranes, and iatrogenic preterm delivery.

Methods: Women who underwent first trimester screening for chromosomal abnormalities between January and November 2011 were included in the study, and a sample of maternal serum was obtained. In total, 1905 women were followed-up through the local record system, and 13 women with spontaneous preterm labor, 17 women with preterm prelabor rupture of membranes (PPROM), and 16 women with iatrogenic preterm delivery were identified. Twenty-two women with uncomplicated pregnancies who delivered at term were selected as controls. Maternal serum azurocidin levels in women were determined using ELISA.

Result: Women with PPROM had lower azurocidin levels (median 0.91?ng/mL, range 0.2–2.07) than women who delivered at term (median 1.63?ng/mL, range 0.4–10.98; p?=?0.02). No differences in azurocidin levels between women with labor at term and those with either spontaneous preterm labor (median 1.46?ng/mL, range 0.19–2.59; p?=?0.42) or iatrogenic preterm delivery (median 1.60?ng/mL, range 0.66–7.96; p?=?0.27) were found.

Conclusions: Low levels of azurocidin in maternal serum in the first trimester were associated with subsequent PPROM.     

Insulin-like growth factor-binding protein-1 in cervical secretion as a predictor of preterm delivery

BACKGROUND: The aim of the study was to evaluate whether the phosphorylated isoforms of insulin-like growth factor-binding protein-1 (IGFBP-1), a protein produced by the decidua, can be detected in cervical secretions of pregnant women with preterm uterine contractions, and whether their presence predicts an increased risk of preterm delivery. METHODS: A prospective analysis of sixty-three women who presented with preterm labor but intact fetal membranes at weeks 22-36+6 days of gestation at the Antenatal clinic at the Department of Obstetrics and Gynecology, Helsinki University Central Hospital. Phosphorylated IGFBP-1 (phIGFBP-1) was measured in cervical swab samples obtained at presentation, using an immunoenzymometric assay. The values > or =10 microg/L were considered as positive. In addition, 58 asymptomatic women at the same gestational stage were studied as controls. Multiple logistic regression was applied to control for confounding variables and to obtain adjusted odds ratios. RESULTS: The concentration of phIGFBP-1 in cervical samples ranged from undetectable to 95 microg/L. In 17 of the 63 (27%) women with preterm labor it was > or =10 microg/L. Seven of these 17 (41%) women with a positive phIGFBP-1 result delivered preterm, all before 35 weeks of gestation. Among the women with preterm labor and a negative phIGFBP-1 result, three of the 46 (7%) delivered before 37 weeks of gestation (adjusted OR 24, 95% CI 1.2-487), but all after 35 weeks of gestation. In the asymptomatic control population three out of 58 (5%) women had a positive cervical phIGFBP-1 test result but none delivered preterm. Among the controls with a negative cervical phIGFBP-1 test result (55 of 58, 95%), one woman delivered preterm (1 of 55, 2%). CONCLUSIONS: Pregnant women who are in preterm labor with intact fetal membranes and who have a positive phIGFBP-1 test result in cervical secretion have an increased risk of preterm delivery.     

The value of interleukin-8, interleukin-6 and interleukin-1beta in vaginal wash as predictors of preterm delivery

AIMS: To study the value of interleukin (IL)-8, IL-6 and IL-1beta in vaginal wash as predictors of preterm delivery. METHODS: A prospective analysis of a study group of 200 pregnant women between 24 and 34 weeks of gestation with intact membranes and preterm labor and a control group of 50 pregnant women during the same period of gestation. The controls had uncomplicated pregnancies and subsequently delivered at term. Samples of vaginal secretions were collected from both groups and analyzed for IL-1beta, IL-6 and IL-8 concentrations. RESULTS: Of the women in the study group, 70 had preterm deliveries, while all women in the control group had full-term deliveries. Compared with the control group, the study group had significantly higher concentrations (p < 0.021) of IL-1beta, IL-6 and IL-8. The women in the study group delivering preterm also had IL-1beta, IL-6 and IL-8 concentrations significantly greater (p < 0.001) than those of the same group delivering full term. ROC curves were used to establish cut-off points for the three interleukins to predict preterm delivery. We did not find a cut-off point with an appropriate sensitivity and specificity. CONCLUSION: The concentrations of interleukins in vaginal wash were significantly higher both in the women with preterm labor and in those delivering preterm. While values differed between controls and those with the preterm labor, no cut-off can be obtained to use the results of IL-1beta, IL-6 and IL-8 as a predictor clinically.     

Evaluation of amniotic fluid cytokines in preterm labor and intact membranes.

OBJECTIVE: To compare the amniotic fluid (AF) concentration of pro-inflammatory cytokines between women with preterm labor and intact membranes that delivered within 7 days, with those that delivered after 7 days of the amniocentesis according to the result of the AF culture. METHODS: Fifty-two women with preterm labor and intact membranes between 21 and 35 weeks of gestation were included in the study. Transabdominal amniocentesis was performed to rule out intra-amniotic infection, and AF concentrations of interleukin-1alpha (IL-1alpha), interleukin-1beta (IL-1beta), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor (TNF) were determined with sensitive and specific enzyme-linked immunosorbent assays. Amniotic fluid was cultured for aerobic and anaerobic bacteria, Ureaplasma urealyticum, and Mycoplasma hominis. Exclusion criteria included preterm premature rupture of membranes, vaginal bleeding, multiple gestations, uterine anomalies, fetal congenital anomalies, ominous fetal heart rate tracings and fetal deaths. Proportions were compared using chi2 or Fisher's exact test. Receiver operator characteristic (ROC) curve analysis was performed for each cytokine for the prediction of delivery within 7 days. RESULTS: Sixty-two percent (32/52) of women delivered within 7 days and 38% (20/52) delivered after 7 days of amniocentesis. All women that delivered after 7 days of the procedure had negative AF cultures. In contrast, 28% (9/32) of women that delivered within 7 days had positive AF cultures and 72% (23/32) had negative AF cultures. Women that delivered within 7 days regardless of AF cultures had a lower birth weight and a shorter amniocentesis-to-delivery interval than those that delivered after 7 days of amniocentesis. Among women that delivered within 7 days, those with positive AF cultures had a lower gestational age at delivery and a higher frequency of histologic chorioamnionitis than those with negative AF cultures. The AF concentrations of all cytokines were significantly higher in women that delivered within 7 days with positive AF cultures than in those with negative AF cultures. Similarly, the AF concentrations of IL-1alpha, IL-6, and IL-8 were significantly higher in women that delivered within 7 days than those that delivered after 7 days of the amniocentesis, regardless of the AF culture results. Diagnostic indexes were calculated for all cytokines using critical values derived from ROC curve analysis for the prediction of delivery within 7 days. CONCLUSIONS: Women with preterm labor and intact membranes that delivered within 7 days had higher AF concentrations of pro-inflammatory cytokines than those who delivered after 7 days of the amniocentesis regardless of the AF culture results.