Joon-Seok Hong

Intraamniotic infection with genital mycoplasmas exhibits a more intense inflammatory response than intraamniotic infection with other microorganisms in patients with preterm premature rupture of membranes

OBJECTIVEnThe objective of the study was to compare the intensity of inflammatory responses between intraamniotic infection with genital mycoplasmas and intraamniotic infection with other microorganisms.nnnSTUDY DESIGNnWe examined the intensity of intraamniotic and maternal inflammatory responses in 99 patients with preterm premature rupture of membranes and a positive amniotic fluid (AF) culture. AF was obtained by transabdominal amniocentesis or at the time of cesarean delivery. Patients were divided according to the recovered microorganisms: (1) genital mycoplasmas (n = 62); (2) other microorganisms (n = 31); or (3) mixed infection (n = 6).nnnRESULTSnThe median AF white blood cell (WBC) count, maternal blood WBC count, and plasma C-reactive protein concentrations were significantly higher in patients with intraamniotic infection with genital mycoplasmas than in those with intraamniotic infection with other microorganisms (P < .05 for each).nnnCONCLUSIONnIntraamniotic and maternal inflammatory responses are more intense in intraamniotic infection with genital mycoplasmas than in intraamniotic infection with other microorganisms in patients with preterm premature rupture of membranes.

Comparative study of induction of labor in nulliparous women with premature rupture of membranes at term compared to those with intact membranes: Duration of labor and mode of delivery

Aim:u2002 To evaluate the effect of premature rupture of membranes (PROM) at term on the duration of labor and mode of delivery in comparison with intact membranes in nulliparous women with an unfavorable cervix whose labor was induced.

Twenty-four percent of patients with clinical chorioamnionitis in preterm gestations have no evidence of either culture-proven intraamniotic infection or intraamniotic inflammation

BACKGROUND: Recent studies on clinical chorioamnionitis at term suggest that some patients with this diagnosis have neither intraamniotic infection nor intraamniotic inflammation. A false‐positive diagnosis of clinical chorioamnionitis in preterm gestation may lead to unwarranted preterm delivery. OBJECTIVE: We sought to determine the frequency of intraamniotic inflammation and microbiologically proven amniotic fluid infection in patients with preterm clinical chorioamnionitis. STUDY DESIGN: Amniocentesis was performed in singleton pregnant women with preterm clinical chorioamnionitis (<36 weeks of gestation). Amniotic fluid was cultured for aerobic and anaerobic bacteria and genital mycoplasmas and assayed for matrix metalloproteinase‐8 concentration. Microbial invasion of the amniotic cavity was defined as a positive amniotic fluid culture; intraamniotic inflammation was defined as an elevated amniotic fluid matrix metalloproteinase‐8 concentration of >23 ng/mL. Nonparametric and survival techniques were used for analysis. RESULTS: Among patients with preterm clinical chorioamnionitis, 24% (12/50) had neither microbiologic evidence of intraamniotic infection nor intraamniotic inflammation. Microbial invasion of the amniotic cavity was present in 34% (18/53) and intraamniotic inflammation in 76% (38/50) of patients. The most common microorganisms isolated from the amniotic cavity were the Ureaplasma species. Finally, patients without microbial invasion of the amniotic cavity or intraamniotic inflammation had significantly lower rates of adverse outcomes (including lower gestational age at delivery, a shorter amniocentesis‐to‐delivery interval, acute histologic chorioamnionitis, acute funisitis, and significant neonatal morbidity) than those with microbial invasion of the amniotic cavity and/or intraamniotic inflammation. CONCLUSION: Among patients with preterm clinical chorioamnionitis, 24% had no evidence of either intraamniotic infection or intraamniotic inflammation, and 66% had negative amniotic fluid cultures, using standard microbiologic techniques. These observations call for a reexamination of the criteria used to diagnose preterm clinical chorioamnionitis.

Relationship between Twin-to-twin Delivery Interval and Umbilical Artery Acid-base Status in the Second Twin

The purpose of this study was to determine the effect of twin-to-twin delivery interval on umbilical artery acid-base status of the second twin at birth. This was a retrospective cohort study of all live-born twins with measured acid-base status in umbilical arterial blood who were delivered after 34 weeks gestation from June 2003 to February 2006. Twins with any maternal or fetal complications were excluded. Subjects were divided into two groups based on the mode of delivery of the first twin: normal cephalic vaginal deliveries (n=40) or cesarean deliveries (n=67). The inter-twin differences in umbilical arterial blood pH, PCO2, PO2, and base excess in twin newborns born vaginally were significantly greater than the corresponding differences in those born by cesarean section. A significant positive correlation was found between twin-to-twin delivery interval and inter-twin difference in umbilical arterial blood pH in twin newborns born vaginally. The umbilical arterial blood pH of the second twin was less than 7.0 in 14% (2/14) in cases delivered more than 20 min after the first twin. The umbilical arterial blood gas status of the second twin worsened with increasing twin-to-twin delivery interval, and pathologic fetal acidemia (pH < 7.0) might develop in the second twin when the twin-to-twin delivery interval was greater than 20 min.

Addition of adjuvant progesterone to physical‐exam‐indicated cervical cerclage to prevent preterm birth

The aim of this study was to assess the effect of vaginal progesterone as an adjuvant therapy to physical‐exam‐indicated cervical cerclage (PEICC).

P11.07: Transvaginal ultrasonographic cervical measurement in predicting failed labor induction and caesarean delivery for failure to progress

Objective: The aim of this study was to find out the relating factors with the actual delivery date in term pregnancy. Methods: Sixty patients with singleton gestation were measured for their lower utrine segment (LUS), cervical length, and cervical gland thickness by transvaginal ultrasonography and for their amnionic fluid index (AFI) by transabdominal ultrasonography from 36 weeks and they were longitudinally followed up until spontaneous vaginal delivery. Regression analysis was used to find out the relevance between these factors and remaining days to delivery date. Results: There was a relationship between cervical length and remaining days to birth in term pregnancy, which could be described as a mathematical equation (remaining days for delivery = 6.12 + 0.24 * cervical length (mm); r = 0.29, p < 0.01). However, no relationship was found between factors such as LUS, AFI, and cervical gland thickness and with remaining days to birth. Conclusions: Remaining days to the actual delivery date in term singletone pregnancy is closely related with cervical length.

OP22.03: Prediction of failed labor induction in multiparous women at term: role of previous obstetric history, digital examination, and sonographic measurement of cervical length

Conclusions: It might be expected that risk of T21 would be the major factor in deciding whether to have an amniocentesis. Although we have shown that risk is indeed a factor that women use to make that decision, our data support our experience that the risk itself is of relatively little importance and other issues are frequently the deciding factor. The issues to resolve are what are the most important factors in the decision making process and what would women chose if not divided into low and high risk but just given their figure?

OP22.04: Prediction of successful labor induction in twin gestation: body mass index, digital examination, and sonographic measurement of cervical length

Methods: This prospective observational study enrolled 110 consecutive multiparous women with singleton gestations scheduled for labor induction at term. Transvaginal ultrasound for measurement of cervical length was performed and the Bishop score was assessed by digital examination. Receiver operating characteristic (ROC) curves and logistic regression were used for statistical analysis. Results: Labor induction failed in 15 women (14%). In terms of previous obstetric history, women with only previous mid-trimester loss or preterm delivery had a significantly higher risk of failed labor induction than those with at least one previous term delivery. Logistic regression demonstrated that both previous obstetric history and the Bishop score were found to be significant and independent contributing factors for failed labor induction. Further examination of the different components of the Bishop score showed that only previous obstetric history provided a significant contribution to the prediction of failed labor induction. To predict the failure of labor induction, the best cut-off value of Bishop score was 3, with a sensitivity of 73% and a specificity of 44%. Conclusions: The previous obstetric history and the Bishop score independently predicted the failure of labor induction in multiparous women. However, sonographic measurement of cervical length appeared to have poor predictive value for the risk of failed induction.

P11.01: Ultrasonographic measurement of cervical length at term in predicting onset of spontaneous labor with intact membranes and premature rupture of membranes

Objective: To determine whether the sonographically measured cervical length at term predicted onset of spontaneous labor with intact membranes and premature rupture of membranes (PROM) within the subsequent 2 weeks. Methods: This prospective observational study enrolled 483 consecutive women with singleton gestations at 37 weeks. Transvaginal ultrasound for measurement of the cervical length and digital vaginal examinations were performed serially at 37 weeks and 39 weeks. Outcomes included the onset of spontaneous labor with intact membranes and the occurrence of PROM at term within the subsequent 2 weeks. Univariate, multivariate and receiver operating characteristic curve analysis were used for statistical analysis. Results: 1) The cervical length at both 37 and 39 weeks was significantly shorter in women who had onset of spontaneous labor with intact membranes within 2 weeks than in those who did not (p < 0.05 for each). 2) The difference in mean cervical length at both 37 and 39 weeks between these two groups remained significant after adjustment for parity, cervical dilatation, effacement and consistency by digital examination, and birth weight (p < 0.05 for each). 3) In the receiver operating characteristic curves, the best cut-off values of cervical length for the prediction of onset of spontaneous labor with intact membranes within 2 weeks were 27 mm at both 37 and 39 weeks. 4) At these cut-off values, sensitivity rates were 61% and 55%, and specificity rates were 62% and 63%, respectively. 5) However, the mean cervical length at either 37 or 39 weeks’ gestation was not significantly different between women whom PROM occurred within 2 weeks and those whom PROM did not. Conclusions: Transvaginal sonographic measurement of cervical length at term can predict onset of spontaneous labor with intact membranes, but not occurrence of PROM, within the subsequent 2 weeks. Cervical length may contribute to physiological process of term human parturition.

P11.10: Prediction of post-term pregnancy in nulliparous women by transvaginal ultrasonographic measurement of cervical length at 20 to 24 weeks and 37 weeks

Objective: External cephalic version (ECV) is an effective tool for reducing the rate of Cesarean in patients with breech presentation at term. While amniotic fluid index has been showed to be associated with successful ECV, there is still uncertainty about which measure should be used to counsel mothers about the likelihood of success. The purpose of this study was to assess the association between the amniotic fluid index (AFI), maximal vertical pocket (MVP), as continuous, categorical and dichotomic variable, and the success rate of ECV. Methods: A prospective observational study was performed including all patients undergoing a trial of ECV between 1988 and 2001 in our center. The association between the different amniotic fluid (AF) measurements and the success of the ECV was calculated using linear and dichotomic logistic regression analyses. Multiple regression analyses with stepwise were performed to adjust for confounding variables including parity, and maternal body mass index (mBMI). Results: Data was available for 1219 patients who underwent a trial of ECV. The rate of successful ECV was 43% in nulliparous and 60% in parous women. A high level of both the AFI and the MVP preprocedure was associated with a successful ECV (Pearson’s R: 0.176 and 0.151, p < 0.001). While there is no cut-off value that preclude a trial of ECV, these levels where strongly associated with successful ECV: an AFI ≥ 12 cm (OR 2.0 95%CI 1.6–2.6), and a MVP ≥ 5 cm (OR 1.9 95%CI 1.5–2.4). After adjustment for confounding factors, an AFI ≥ 12 cm (OR 2.3, 95%CI 1.7–3.0) remained most predictive of successful ECV, after parity ≥ 1 (OR 2.5, 95%CI 1.8–3.3) and mBMI < 35 kg/m2 (OR 3.7 95%CI 1.8–7.8). Conclusion: Both AFI and MVP can be used in combination with parity and mBMI to counsel women prior a trial of ECV. However, an AFI equal or greater than 12 cm seems to be the best AF-related variable associated with successful ECV.