Stages Of Cervical Dilatation Research Articles

Labor dystocia and oxytocin augmentation before or after six centimeters cervical dilatation, in nulliparous women with spontaneous labor, in relation to mode of birth

BackgroundThe effects of diagnosing and treating labor dystocia with oxytocin infusion at different cervical dilatations have not been fully evaluated. Therefore, we aimed to examine whether cervical dilatation at diagnosis of dystocia and initiation of oxytocin infusion at different stages of cervical dilatation were associated with mode of birth, obstetric complications and women’s birthing experience.MethodsA retrospective cohort study, including 588 nulliparous term women with spontaneous onset of labor and dystocia requiring oxytocin augmentation. The study population was divided into three groups according to cervical dilatation at diagnosis of dystocia and initiation of oxytocin-infusion (≤ 5 cm, 6–10 cm, fully dilated) with mode of birth as the primary outcome. Secondary outcomes were obstetrical and neonatal complications and women´s experience of childbirth. Statistical comparison between groups using Chi-square and ANOVA was performed. The risk of operative birth (cesarean section and instrumental birth) was assessed using binary logistic regression with suitable adjustments (maternal age, body mass index and risk assessment on admission to the labor ward).ResultsThe cesarean section rate differed between the groups (p < 0.001); 12% in the ≤ 5 cm group, 6% in the 6–10 cm group and 0% in the fully dilated group. There was no increased risk for operative birth in the ≤ 5 cm group compared to the 6–10 cm group, adjusted OR 1.28 95%CI (0.78–2.08). The fully dilated group had a decreased risk of operative birth (adjusted OR 0.48 95%CI (0.27–0.85). The rate of a negative birthing experience was high in all groups (28.5%, 19% and 18%) but was only increased among women in the ≤ 5 cm group compared with the 6–10 cm group, adjusted OR 1.76 95%CI (1.05–2.95).ConclusionsAlthough no difference in the risk of operative birth was found between the ≤ 5 cm and 6-10 cm cervical dilatation-groups, the cesarean section rate was highest in women with dystocia requiring oxytocin augmentation at ≤ 5 cm cervical dilatation. This might indicate that oxytocin augmentation before 6 cm cervical dilatation could be contra-productive in preventing cesarean sections. Further, the increased risk of negative birth experience in the ≤ 5 cm group should be kept in mind to improve labor care.

Comparison of the effect of educational software and booklet on anxiety and pain during labour: a randomised controlled clinical trial

This randomised clinical trial was conducted on 153 pregnant women. Participants were assigned into two intervention groups including educational software and an educational booklet and a control group through block randomisation. A training session was implemented for the intervention groups at 30–36 weeks and they were taught how to use the educational methods. Participants were followed-up until the childbirth time and the severity of pain was measured at four stage of cervical dilatation (4, 6, 8 and 10 cm) by Visual Analogue Scale (VAS). Spielberger State-Trait Anxiety Inventory was completed at 4–5 cm cervical dilatation. There was no significant difference between groups in terms of the labour pain intensity (p > .05). After intervention, mean (SD) of state anxiety score was 38.7 (2.6) in educational software group, 44.3 (7.4) in educational booklet group and 63.3 (8.2) in control group. Also, mean (SD) of trait anxiety score was 47.4 (2.7) in educational software group, 47.2 (2.4) in educational booklet group and 61.8 (3.9) in control group. The mean state and trait anxiety scores in both intervention groups were significantly lower than control group (p < .001). Both intervention groups were effective in reducing anxiety. Thus, these educational methods should be recommended for pregnant women in clinical practices. IMPACT STATEMENT What is already known on this subject? Childbirth is one of the most important crises in women’s life, in which stress and other forms of emotional distress such as anxiety are likely to occur during it. Safe practices and effective interventions can be offered to pregnant women to tolerate the labour pain and reduce anxiety during labour. What do the results of this study add? There was no statistically significant difference between two intervention groups (educational software and educational booklet groups) and control group in terms of the pain intensity at the cervical dilatation of 4, 6, 8 and 10 cm. But the state and trait anxiety in both groups (educational software and educational booklet groups) was significantly less than the control group. Also, the anxiety level was significantly lower in the educational software group than the educational booklet group. What are the implications of these findings for clinical practice and/or future research? Educational software and booklet with educational content about position modification during pregnancy, stretching exercises, breathing techniques and exercises, relaxation and lower back massage for reducing anxiety should be recommended for pregnant women in clinical practices.

Amniotic fluid adhesion molecules during parturition at term

During term parturition a constant elevation of intercellular adhesion molecule (ICAM-1) as well as increases of endothelial leukocyte adhesion molecule (ELAM-1) and vascular cell adhesion molecule (VCAM-1) in the lower uterine segment and of ICAM-1 in fetal membranes were observed. We examined ELAM-1, ICAM-1 and VCAM-1 during normal term parturition to find out whether amniotic fluid adhesion molecules change accordingly. Amniotic fluid specimens of 35 patients undergoing cesarean section at term with various stages of cervical dilatation (<2 cm, n=11; 2-<4 cm, n=10; 4-6 cm, n=6; >6 cm, n=8) and different durations of labor (0 h, n=11; >0 h, n=24) were examined for ELAM-1, ICAM-1 and VCAM-1 by enzyme immunoassay. For statistical analysis one-way ANOVA (cervical dilatation) and unpaired t-test (duration of labor) were used (P<0.05). Neither ELAM-1 nor VCAM-1 correlated with cervical dilatation or with the duration of labor. ICAM-1 showed a tendency to decline with the last phase of cervical dilatation (P=0.06) and a significant decline with labor (P=0.046). In contrast to adhesion molecules in the lower uterine segment amniotic fluid adhesion molecules ELAM-1 and VCAM-1 do not rise significantly during parturition. The decline of ICAM-1 may be due to a transfer to other compartments (i.e., lower uterine segment or retroplacental blood) thereby contributing to labor and cervical dilatation.

Exploring the effect of hospital admission on contraction patterns and labour outcomes using women's perceptions of events

Objective this study investigated the phenomenon of spontaneous labour contractions becoming less frequent on admission to hospital, which is observed anecdotally but is not evident in the literature. Anxiety in response to hospitalisation has been proposed to be responsible by initiating the biochemical response termed ‘fight or flight’. Design A non-experimental prospective design and a combination of quantitative and qualitative analysis. Data were collected using self-report labour diaries, postnatal questionnaires and hospital records of labour. Univariate analysis using t-test and χ 2-test was performed to examine relationships between variables, and content analysis was undertaken on qualitative data regarding reactions to hospitalisation. Setting hospital and community maternity services provided by a National Health Service hospital in Southern England in 1997. Participants about 87 women at least 37-week gestation, uncomplicated singleton pregnancy anticipating spontaneous labour with a live fetus. Measurements and findings labour diaries were analysed from 26 births. In three home births and 11 hospital births, labour contractions became more frequent, but in the remaining 12 labours, contractions decreased after admission to hospital. Women whose contractions slowed were not more anxious, but they rarely had cervical dilatation over 5 cm and usually assumed a recumbent position in hospital. Artificial rupture of membranes was performed more frequently in these women, they used more pain relief and had a higher incidence of complicated childbirth; however, these differences were not statistically significant. Key conclusions labour contractions can increase or decrease in frequency following admission to hospital, and the change of frequency may be associated with stage of cervical dilatation and posture rather than anxiety. Implications for practice routine intervention to speed up labour on the basis of admission observations is called into question, and women should be made aware that slowing of contractions can occur as a normal part of changing the labour environment. Further research is needed to determine the physiological parameters of spontaneous labour and the role of posture in labour progress is needed.

Uterine activity and ductus venosus flow velocity patterns during the first stage of labor

Objective: To analyze the effects of uterine contractions on ductus venosus (DV) pulsatility during the first stage of labor. Methods: Twenty healthy women were examined. Measurements were taken at three stages of cervical dilatation (< 4 cm, 4–7 cm and ≥ 8 cm) during and between contractions. Peak velocity during ventricular systole ( S) and atrial contraction ( A), pulsatility index for veins (DV PIV), ductus venosus index (DVI) and the S/ A ratio were measured. Results: The DV was observed successfully in 16 cases. The mean S velocity did not change significantly (64 cm/s during and 65 cm/s between contractions). The mean A velocity decreased significantly from 35 cm/s measured between contractions to 29 cm/s during contractions ( P < 0.0001). The mean DV PIV and DVI were significantly higher during contractions (0.72 and 0.55) than between contractions (0.57 and 0.45) ( P < 0.0001). There were no significant differences in means between stages of cervical dilatation. Conclusion: Significant differences during and between uterine contractions can be observed in DV pulsatility during normal labor.

Estorgen Receptor α and Progesterone Receptor A and B Concentration and Localization the Lower Uterine Segment in Term Parturition

To determine the localization and concentrations of estrogen receptor alpha and progesterone receptors A and B in the lower uterine segment during term parturition. Biopsies were taken from 70 patients during nonelective cesarean delivery. The patients were at different stages of cervical dilatation (<2 cm, 2-3.9 cm, 4-6 cm, >6 cm) and different duration of labor (< or =6 hours, >6-12 hours, >12 hours). The receptor concentrations were determined with solid phase immunoassays, and their localization was investigated immunohistochemically. Estrogen receptor alpha concentration decreased significantly from 2.12 fmol/mg protein at less than 2 cm dilatation to 1.08 fmol/mg (4-6 cm) but tended to increase at greater than 6 cm. Progesterone receptor A and B concentration was 84.7 fmol/mg at less than 2 cm dilatation, decreased significantly to 36.6 fmol/mg (2-3.9 cm), and increased again with further dilation. Concentrations of both receptors did not depend on duration of labor. By immunohistochemistry only progesterone receptor A and B was found to be expressed by endothelial and smooth muscle cells of the vessels, stromal fibroblasts, smooth muscle cells in the myometrium, and glandular epithelial cells. Regardless of the extent of cervical dilatation, expression of progesterone receptors A and B was marked. A decrease in estrogen receptor alpha and progesterone receptor A and B concentration in the early phase of first stage labor may play a role in cervical dilation at term.

Quantitation and localization of inflammatory cytokines interleukin-6 and interleukin-8 in the lower uterine segment during cervical dilatation.

Cervical dilatation during parturition is associated with a significant increase of interleukin (IL)-6 and IL-8. The purpose of this study was to localize the respective messenger RNA and to quantitate their protein levels during various stages of dilatation. Protein extracts from 34 biopsy specimens of the lower uterine segment at various stages of cervical dilatation (<2, 2 to <4, 4-6, and >6 cm) were subjected to enzyme linked immunosorbent assay for IL-6 and IL-8 to document their concentration. The respective mRNA expression was studied using reverse transcriptase PCR using IL-6 and IL-8 specific primers. Localization of IL-6 and IL-8 was done by in situ hybridization using biotinylated probes. The IL-6 and IL-8 concentrations increased significantly in the lower uterine segment tissues at 4-6 cm of dilatation. Expression of IL-8 was seen in all the tissues at or more than 4 cm dilatation, whereas IL-6 expression was inconsistent. In situ hybridization localized IL-6 and IL-8 mRNA to the glandular epithelium. The increase in the inflammatory cytokines (IL-6 and IL-8) during parturition is associated with cervical effacement.

Concentration of estrogen and progesterone receptors in the lower uterine segment at term labor

To determine cytosol estrogen and progesterone receptor concentrations in the human lower uterine segment in different stages of cervical dilatation during parturition at term. Biopsy specimens of the lower uterine segment were obtained from 51 women undergoing non-elective cesarean section at term. The stage of cervical dilatation at the time of cesarean section was < 2 cm (N = 14), 2 to < 4 cm (N = 13), 4 to 6 cm (N = 11) or > 6 cm (N = 13). The cytosolic estrogen and progesterone receptor concentrations were determined by enzyme immunoassays. Median estrogen receptor concentrations at < 2 cm and at 2-< 4 cm cervical dilatation were 2.12 fmol/mg protein and 2.03 fmol/mg protein, respectively. After a significant drop at 4-6 cm cervical dilatation (median: 1.08 fmol/mg protein), estrogen receptor concentrations raised again at > 6 cm cervical dilatation (median: 2.00 fmol/mg protein). Median progesterone receptor concentration was 84.7 fmol/mg protein at < 2 cm cervical dilatation, diminished significantly at 2-< 4 cm cervical dilatation (36.6 fmol/mg protein) and increased at further cervical dilatation (4-6 cm: 75.7 fmol/mg protein; > 6 cm: 83.7 fmol/mg protein). These data suggest that predominantly a decrease in cytosolic concentration of the progesterone receptor at the beginning of the active phase of first stage labor may play a crucial role in the hormonal control of cervical dilatation during parturition at term.

Epidural and prolonged course of labor: Casual or causal

T HE EFFECT OF epidural analgesia on course of labor is a controversial issue that has been of concern for many decades. However, recent reports by Thorp et al 1 tried to implicate epidural analgesia as an important cause of dystocia and cesarean section. In their 1991 study, they reported an associated cesarean section of 14.1% (11.4% for dystocia). Later in 1993, investigators intended to study 200 parturients in a randomized fashion either to receive intravenous opioids (75 mg meperidine and 25 mg promethazine) or epidural analgesia (0.25 % bupivacaine followed up by a continuous infusion of 0.125%). 2 Thorp et al stated that patients receiving epidural analgesia experienced prolongation of first and second stages of labor, had twice need for oxvtocin augmentation, and a much higher cesarean section rate (25% v 2.2%) mainly caused by dystocia. They only conducted study on 93 patients and terminated it prematurely because of the unacceptable high incidence of cesarean section. However, their study was criticized for many reasons. 3 The criticism of Thorp et al study included several factors. First, element of bias. The obstetricians who made decision to perform cesarean section were participants in study. The obstetricians were also aware-of type of analgesia, and had previously reported that epidural anesthesia caused a higher incidence of cesarean section. Second, anesthetic management was not detailed and epidural analgesia was not a well-established technique in center where study was performed. Third. premature termination of study and possible change in statistical difference had a few cases been added, threw doubts on results. Fourth, Thorp et al did not explain why in one study, conducted by same investigators, incidence of cesarean section was 14% while in this study it was 25%. Fifth, in their study, incidence of cesarean section with or without epidural analgesia (25.0% v 2.2%) is quite different from experience of other centers. Sixth, there were no specific guidelines in protocol to follow for management of labor. Thorp et al's study, unjustifiably, stated that most of cases requiring cesarean section for dystocia were associated with administration of epidural analgesia when cervical dilatation was less than 5 cm. Thus. their conclusion that epidural analgesia should not be used before that stage of cervical dilatation has led to unnecessary suffering of parturients, particularly those with induced labor and oxytocin augmentation. To answer question whether early administration of epidural analgesia would affect obstetrical outcome. Chestnut et al4,s conducted 2 studies in nulliparous women. Their first study included 149 parturients receiving intravenous (IV) oxytocin divided into 2 groups. 4 In one group, epidural analgesia was started after 3-cm cervical dilatation and before 5-cm dilatation. In other group, epidural analgesia was initiated when cervical dilatation reached at least 5 cm, and control of pain was attempted by IV nalbuphine between 3and 5-cm dilatation. These investigators found that early administration of epidural analgesia did not prolong first or second stage of labor, increase dystocia, increase operative delivery, or adversely affect fetus or neonate. Moreover, patient satisfaction was much higher with early epidural analgesia. In Chestnut et al's s second study, labor spontaneously occun'ed. Three hundred forty-four parturients were divided into 2 similar groups. They found that early administration of epidural analgesia did not increase incidence of oxytocin augmentation, prolong interval between randomization and diagnosis of complete cervical dilation, or increase incidence of malposition of vertex at delivery. Also, early administration of epidural analgesia did not result in an increased incidence of cesarean section or instrumental delivery, eg, incidence of cesarean

Collagenolysis in the lower uterine segment during parturition at term: Correlations with stage of cervical dilatation and duration of labor

Objective: The objective of this study was to quantify the extent of neutrophil infiltration and the concentrations of enzymes involved in collagenolysis in the lower uterine segment in relation to the degree of cervical dilatation and the duration of labor. Study Design: Biopsy specimens of the lower uterine segment were obtained from 62 women undergoing cesarean section at term. The number of extravascular neutrophils was assessed with enzyme histochemical evaluation, and the concentrations of matrix metalloproteinase-8, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinases-1 by were assessed by enzyme-linked immunosorbent assay. Results: The neutrophil count and the concentrations of matrix metalloproteinase-8, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinases-1 increased with increasing cervical dilatation. At >6 cm the neutrophil count and the concentrations of matrix metalloproteinase-8, matrix metalloproteinase-9, and tissue inhibitor of metalloproteinases-1 were significantly higher than at <2 cm. An association with the duration of labor was found for the neutrophil count and the concentrations of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinases-1. Multiple linear regression analysis showed that the degree of cervical dilatation is more closely related to the 4 laboratory parameters investigated than to the duration of labor. Conclusion: The findings support the hypothesis that local changes (ie, collagenolysis) in the lower uterine segment unrelated to uterine activity play a crucial role in cervical dilatation at term. (Am J Obstet Gynecol 1999;181:153-8.)

Parturition at term: parallel increases in interleukin-8 and proteinase concentrations and neutrophil count in the lower uterine segment.

A relationship was sought between the tissue concentrations of interleukin (IL)-8, matrix metalloproteinase (MMP)-8 and MMP-9, and the numbers of the various leukocytes infiltrating the lower uterine segment stroma during parturition. Biopsy specimens of the lower uterine segment were obtained from 63 women undergoing Caesarean section at various stages of cervical dilatation at term. The concentrations of IL-8, MMP-8 and MMP-9 were determined with enzyme-linked immunosorbent assays, and the leukocytes were quantified immunohistochemically. The median IL-8 concentration (pg/mg total protein) rose significantly from 17.2 at < 2 cm dilatation, to 26.5 at 2 to < 4 cm dilatation, and 1954.0 at 4-6 cm dilatation, and remained at approximately this concentration at > 6 cm dilatation. The median MMP-8 concentration (ng/mg total protein) increased significantly from 32.2 at < 2 cm dilatation to 114.2 at > 6 cm dilatation. The median MMP-9 concentration (ng/mg total protein) rose significantly from 15.4 at < 2 cm dilatation to 102.1 at > 6 cm dilatation. The number of neutrophils was significantly higher at 4-6 cm and > 6 cm dilatation than at > 2 cm, reaching maximum values at > 6 cm dilatation. The findings in this study support the hypothesis that IL-8-induced infiltration of the cervical stroma by neutrophils and subsequent release of proteinases may play a key role in parturition.

Expression of cell adhesion molecules by endothelium in the human lower uterine segment during parturition at term

OBJECTIVE: Our purpose was to determine whether the expression of certain adhesion molecules by endothelium in the human lower uterine segment at term varies with the degree of cervical dilatation. STUDY DESIGN: Biopsy specimens of the lower uterine segment of 34 women undergoing cesarean section at term at various stages of cervical dilatation were immunostained for endothelial leukocyte adhesion molecule-1, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, and platelet-endothelial cell adhesion molecule. RESULTS: The expression of endothelial leukocyte adhesion molecule-1 was significantly greater at more than 6 cm dilatation than at less than 2 cm ( p = 0.00031) as was that of vascular cell adhesion molecule-1 ( p = 0.033). Expression of intercellular adhesion molecule-1 and platelet-endothelial cell adhesion molecule did not vary with the degree of cervical dilatation. CONCLUSION: Cervical dilatation is associated with up-regulation of certain endothelial cell adhesion molecules. The findings support the hypothesis that certain processes associated with cervical dilatation at term resemble those involved in the acute inflammatory reaction. (Am J Obstet Gynecol 1998;178:557-61.)

Die Muttermundseröffnung am Termin als akute Entzündungsreaktion

Voraussetzung für die Extravasation der mit progredienter Muttermundseröffnung zunehmenden Zahl neutrophiler Granulozyten im zervikalen Stroma ist eine Adhäsivitätssteigerung des Gefäßendothels, die durch Adhäsionsmoleküle vermittelt wird. Deren Expression wird u.a. durch Interleukin (IL)-Iβ gesteuert. Fragestellung: Verändern sich die IL-1 ß-Konzentration und die Expression von endothelial leukocyte adhesion molecule-1 (ELAM-1), vascular cell adhesion mole-cule-1 (VCAM-1) und intercellular adhesion molecule-1 (ICAM-1) im unteren Uterinsegment während der Muttermundseröffnung? Patientinnen und Methodik: Bei Kaiserschnitten am Geburtstermin erfolgt bei einer Muttermundsweite von < 2 cm (n = 17), 2-3cm (n = 12), 4-6cm (n = 13) und>6cm (n=17) eine Gewebeentnahme aus dem unteren Uterinsegment. Die IL-1ß-Konzentration wurde in den Gewebeextrakten mittels ELISA bestimmt und die Expression von ELAM-1, VCAM-1 und ICAM-1 im Gefrierschnitt immunhistochemisch untersucht. Waren ≥ 5% der Endothelzellen angefärbt, wurde der Schnitt als immunreaktiv für das entsprechende Ashäsionsmolekül bewertet. Ergebnisse: Der Median der IL-1 β-Konzentrationen stieg signifikant von 1,3 pg/mg Gesamt-Protein (GP) bei < 2 cm dilatierter Zervix auf 22,2 pg/mg GP bei 4-6 cm eröffneter Zervix an und fiel bei > 6 cm dilatierter Zervix geringgradig auf 13,2 pg/mg GP ab. ELAM-1 war ab einer Muttermundsweite von 2 cm stärker exprimiert, die Expression bei einer Muttermundsweite >6cm war signifikant höher als die bei <2cm eröffneter Zervix. VCAM-1 zeigte, verglichen mit einer Muttermundsweite < 2 cm, bei >6cm Dilatation eine signifikant höhere Expression. ICAM-1 war in allen Gruppen gleichermaßen stark exprimiert. Schlußfolgerung: Der Nachweis einer parallelen Zunahme der Konzentration von IL-1β und der Expression von Adhäsionsmolekülen im unteren Uterinsegment unter der Geburt stützt die Hypothese, nach der die physiologische Muttermundseröffnung mit Veränderungen einhergeht, die denen einer akuten Entzündungsreaktion ähnlich sind.

Characteristics of Labor Pain at Two Stages of Cervical Dilatation

Characteristics of Labor Pain at Two Stages of Cervical Dilatation

Quantitative relationships between pain intensities during labor and beta-endorphin and cortisol concentrations in plasma. Decline of the hormone concentrations in the early postpartum period

In 38 women with uncomplicated vaginal delivery at term, the different pain intensities during spontaneous labor were correlated to the plasma beta-endorphin and cortisol concentrations simultaneously examined. The pain intensities subjectively assessed were numerically categorized. The women in labor categorized to pain intensities 0 to III were in comparable stages of cervical dilatation. The hormone concentrations were measured by means of radioimmunoassay. The lowest hormone levels were found after abolition of pains of labor by epidural anesthesia: beta-endorphin 42 pg/ml, cortisol 318 ng/ml (mean values). The hormone concentrations rose progressively with increasing intensities of labor pain. The highest concentrations were observed in the first few minutes after delivery i.e. immediately after cessation of the extreme pains of expulsive labor: beta-endorphin 118 pg/ml, cortisol 449 ng/ml. Statistically significant, positive correlations were calculated between beta-endorphin and cortisol concentrations in plasma and the self-reported pain intensities (p less than 0.001 and p less than 0.01 resp.). Thus, highly elevated beta-endorphin levels in plasma do not abolish pain, probably they modulate it. Within the first four hours postpartum the concentrations of the two stress-stimulated hormones dropped rapidly. The endorphin level fell from 118 pg/ml immediately after delivery to 38 pg/ml in the above mentioned period, the cortisol level from 449 ng/ml to 302 ng/ml. One to three days after delivery the beta-endorphin and cortisol concentrations in maternal plasma were largely normalized, this means they then approximately corresponded to the values being found in nonpregnant women under normal conditions.

Partograms and nomograms of cervical dilatation in management of primigravid labour.

Philpott's graphic labour has been modified and used in 15,000 labours; it has been unanimously accepted by the staff. A nomogram has been constructed to show the normal progressive dilatation of the cervix for primigravidae admitted at different stages of cervical dilatation. Retrospective evaluation of the nomogram showed that it can separate normal labour from labour destined to result in an abnormal outcome, such as longer first and second stages, a greater incidence of instrumental delivery, and babies with low Apgar scores.It is suggested that the use of a stencil representing normal labour progress, together with Philpott's partogram, will be of considerable use, both in specialist and in general-practitioner units.