Low-risk Nulliparous Women Research Articles

Limited accuracy of the hyperbaric index, ambulatory blood pressure and sphygmomanometry measurements in predicting gestational hypertension and preeclampsia

The aim of this study was to validate the hyperbaric index (HBI) for first trimester prediction of preeclampsia and gestational hypertension. Participants were low-risk and high-risk nulliparous women and high-risk multiparous women, and were recruited between April 2004 and June 2006. At a gestational age of 9 weeks (range 8-11 weeks), blood pressure (BP) was measured first by sphygmomanometry and thereafter by ambulatory BP measurement (ABPM) for 48 h. The first 90 low-risk women who had an uneventful pregnancy formed the reference group for calculation of a time-specified tolerance interval with 90% confidence limits. In the validation group, consisting of the remaining women, the HBI was calculated as the time-specified BP excess over this tolerance limit for SBP, DBP and mean arterial pressure. The validation group contained 101 women. Fifteen women developed preeclampsia and 13 developed gestational hypertension. For preeclampsia, the maximum HBI had the best predictive capacity with a sensitivity of 73% and a specificity of 86%. However, the difference with standard ABPM measurement or sphygmomanometry was small with a sensitivity between 75 and 73% and a specificity between 86 and 95%. The predictive efficacy for gestational hypertension was poor with all methods (sensitivity between 54 and 77%, specificity between 41 and 78%). Standardized sphygmomanometry, ABPM measurement and the HBI calculated from 48-h ABPM had a comparable, restricted predictive efficacy. The high predictive value of HBI as observed in earlier studies could not be reproduced.

Cost Analysis of the Dutch Obstetric System: low-risk nulliparous women preferring home or short-stay hospital birth - a prospective non-randomised controlled study

BackgroundIn the Netherlands, pregnant women without medical complications can decide where they want to give birth, at home or in a short-stay hospital setting with a midwife. However, a decrease in the home birth rate during the last decennium may have raised the societal costs of giving birth. The objective of this study is to compare the societal costs of home births with those of births in a short-stay hospital setting.MethodsThis study is a cost analysis based on the findings of a multicenter prospective non-randomised study comparing two groups of nulliparous women with different preferences for where to give birth, at home or in a short-stay hospital setting. Data were collected using cost diaries, questionnaires and birth registration forms. Analysis of the data is divided into a base case analysis and a sensitivity analysis.ResultsIn the group of home births, the total societal costs associated with giving birth at home were €3,695 (per birth), compared with €3,950 per birth in the group for short-stay hospital births. Statistically significant differences between both groups were found regarding the following cost categories 'Cost of contacts with health care professionals during delivery' (€138.38 vs. €87.94, -50 (2.5-97.5 percentile range (PR)-76;-25), p < 0.05), 'cost of maternity care at home' (€1,551.69 vs. €1,240.69, -311 (PR -485; -150), p < 0.05) and 'cost of hospitalisation mother' (€707.77 vs. 959.06, 251 (PR 69;433), p < 0.05). The highest costs are for hospitalisation (41% of all costs). Because there is a relatively high amount of (partly) missing data, a sensitivity analysis was performed, in which all missing data were included in the analysis by means of general mean substitution. In the sensitivity analysis, the total costs associated with home birth are €4,364 per birth, and €4,541 per birth for short-stay hospital births.ConclusionThe total costs associated with pregnancy, delivery, and postpartum care are comparable for home birth and short-stay hospital birth. The most important differences in costs between the home birth group and the short-stay hospital birth group are associated with maternity care assistance, hospitalisation, and travelling costs.

The choice of obstetric care by low-risk pregnant women in the Netherlands: Implications for policy and management

In the Netherlands, pregnant women at low risk of complications during pregnancy, have the opportunity to choose freely between giving birth at home or in a hospital maternity unit. This study analyses how various attributes of obstetric care, socio-economic characteristics and attitudes influence the decisions that these women make with regard to obstetric care. The method of discrete-choice experiment was applied in the process of data collection and analysis. The data were collected among low-risk nulliparous pregnant women. The analysis suggests that there are strong preferences among some Dutch women for a home birth. Nevertheless, the absence of a medical pain-relief treatment during home birth, might provide incentives for some women to opt for a birth in a hospital, especially at the end of their pregnancy. If the attractiveness of home birth should be preserved in the Netherlands, specific attention should be paid on the approach to pain during a home birth. Efforts could also be made in offering a domestic atmosphere during hospital births to improve hospital-based obstetric care in view of women's preferences.

Incidence and outcomes of dystocia in the active phase of labor in term nulliparous women with spontaneous labor onset

To estimate the incidence of dystocia among nulliparous women without apparent co-morbidity and to examine maternal and fetal short-term outcomes after dystocia. A multi-center cohort study with prospectively collected data. Nine obstetric departments with annual birth rates between 850 and 5,400. Low-risk nulliparous women in term spontaneous labor with a singleton fetus in cephalic presentation. Follow-up of 2,810 nulliparas using self-administered questionnaires supplemented with clinical records. CRITERIA FOR DYSTOCIA: Cervical dilatation < or =2 cm over four hours during the first stage of labor or no descent during two hours (three hours with epidural analgesia) in the descending phase of second stage or no progress for one hour during the expulsive phase of the second stage. Inclusion took place between May 2004 and July 2005. Incidences of dystocia, maternal, and fetal outcomes. The cumulative incidence of dystocia was 37% and of the diagnoses 61% were given in the second stage of labor. Women with dystocia treated by augmentation had more cesarean and ventouse deliveries, more often non-clear amniotic fluid, more post-partum hemorrhage and their children were more often given low one-minute neonatal Apgar scores as compared to women delivered without a diagnosis of dystocia. A dystocia incidence of 37% was found in healthy term nulliparas with no indication for induction or elective cesarean delivery. The adverse maternal and neonatal birth outcomes may be related to the cause of dystocia or to augmentation of labor and this question calls for further studies.

Why women do not accept randomisation for place of birth: feasibility of a RCT in the Netherlands

The purpose of this study was to investigate why low-risk nulliparae were not willing to participate in a randomised controlled trial (RCT) of place of birth. Prospective study. The Netherlands. All low-risk nulliparous women starting their pregnancy under midwife. A questionnaire for 107 nulliparae who were willing to participate in a cohort study on place of birth, but at an earlier stage in their pregnancy declined to participate in a RCT of place of birth. This questionnaire included 12 items on a 4-point Likert scale but was not subjected to formal validation. Reasons why nulliparae did not accept randomisation of place of birth. The most important reason why women refused participation in the trial was that they had already chosen their place of birth before they were asked to participate at 12 weeks of pregnancy. From their answers, it became clear that pregnant women strongly value their autonomy of choice. The decision not to participate in the trial was not influenced by the information given by the midwife and the additional written information. Factors that prevent randomisation for place of birth are difficult to influence. There is a need to explore why there is such certainty of view among women having their first child. Until we have an understanding of why women select information to make these choices and why women are reluctant to participate in trials that challenge choice, it may well be impossible to mount a trial of place of birth.

8: A randomized controlled trial of antioxidant vitamins to prevent serious complications associated with pregnancy related hypertension in low risk, nulliparous women

Oxidative stress is proposed as a central pathophysiological factor in preeclampsia. Although in a small randomized controlled trial in 1999, antioxidant Vitamins C and E reduced the incidence of preeclampsia by 60%, recent larger trials of low risk and high risk women showed no benefit and suggested fetal risk. This trial evaluated the effectiveness of antioxidant therapy to prevent serious morbidity associated with pregnancy related hypertension. In this randomized, placebo controlled, doubly masked trial of low risk nulliparous women, daily treatment with Vitamins C (1000 mg) and E (400 IU) (vitamins) or placebo began at 9 - 16 weeks gestation. The primary outcome was severe pregnancy related hypertension or pregnancy related hypertension with at least one of the following: renal or hepatic dysfunction, thrombocytopenia, eclampsia, indicated preterm delivery < 32 weeks gestation, small for gestational age infant (< 3rd centile), stillbirth or neonatal death up to discharge. Secondary outcomes included preeclampsia diagnosis and measures of maternal and fetal/neonatal safety. From 2003 - 2008 10,154 women enrolled. Loss to follow up was 1.8% resulting in 4993 recieiving vitamins and 4976 placebo. Recruitment was at an average of 13.4 weeks with 44% enrolled before 13 weeks. Demographic findings did not differ by treatment. The racial mix was diverse with 31% Hispanic and 26% African American. The mean prepregnancy BMI was 25.4 ± 6.0, 16% were smokers, and 77% entered the trial taking multivitamins. Vitamin therapy did not reduce the primary outcome (vitamins = 6.1% placebo = 5.8%) or the incidence of preeclampsia (vitamins = 7.2% placebo = 6.7%). Therapy initiated with the antioxidant Vitamins C and E prior to 17 weeks gestation in nulliparous low risk women does not reduce the frequency of serious complications associated with pregnancy related hypertension, nor does this treatment reduce the diagnosis of preeclampsia.

A Randomised Controlled Trial of Early Versus Delayed Oxytocin Augmentation to Treat Primary Dysfunctional Labour in Nulliparous Women

Primary dysfunctional labor, the most common indication for caesarean section, accounts for 30% of caesarean births, and is primarily a problem in nulliparous women. Oxytocin has been widely used to hasten labor in such women, but there is little or no data in randomized trials of sufficient sample size to support the contention that oxytocin reduces the need for caesarean section. In this unblinded prospective randomized controlled trial, 412 low-risk nulliparous women with primary dysfunctional labor were assigned to receive either immediate oxytocin administration (active group, n = 208) or oxytocin withheld for up to 8 hours (control group, n = 204). Neither obstetricians nor participants were blinded to the treatment group. Baseline characteristics were similar in both groups. The Edinburgh Postnatal Depression Scale (EPDS) assessed the rate of maternal major depression within 48 hours of delivery through use of a questionnaire. Early oxytocin produced no significant reduction in caesarean section rates (13.5% active versus 13.7% controls (odds ratio [OR] 0.98, 95% confidence interval [CI] 0.6-1.7), but shortened labor by over 3 hours (active group: 5 hours 52 minutes (3:57-8:28) versus control group 9 hours 8 minutes (5:06-13:16) [P <.001]). Early use may also reduce the rate of operative vaginal delivery (24.5% active versus 30.9% controls, OR 0.73, 95% CI 0.5-1.1). Early oxytocin did not reduce short-term postnatal depression nor was there any significant difference between the treatment groups in maternal or neonatal complications. One perinatal death occurred in each group. This is the largest randomized controlled trial published in full that supports early use of oxytocin to reduce the length of labor in nulliparous women with primary dysfunctional labor. The authors conclude from these findings that early oxytocin may reduce operative vaginal deliveries, but no support is provided for the contention that it reduces rates of caesarean section.

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A randomised controlled trial of early versus delayed oxytocin augmentation to treat primary dysfunctional labour in nulliparous women

Oxytocin is widely used to speed up slow labour, especially in nulliparous women, but randomised trials, apart from one reported only in abstract, have been too small to exclude important effects. To test the hypothesis that early use of oxytocin reduces the need for caesarean delivery. A randomised controlled trial. Twelve obstetric units within the Northern and Yorkshire regions in the North East of England. A total of 412 low-risk nulliparous women in spontaneous labour at term, who had been diagnosed with primary dysfunctional labour were recruited from January 1999 to December 2001. Immediate oxytocin administration (active group) or oxytocin withheld for up to 8 hours (conservative group). Caesarean section and operative vaginal delivery rates. The length of labour measured from the time of randomisation to delivery. The rate of maternal Edinburgh Postnatal Depression Scale (EPDS) greater than 12 (major depression) within 48 hours of delivery. The caesarean section rates were 13.5% active versus 13.7% controls (OR 0.98, 95% CI 0.6-1.7). Operative delivery, 24.5% versus 30.9% (OR 0.73, 95% CI 0.5-1.1). The median (interquartile range) randomisation to delivery interval in the active group was 5 hours 52 minutes (3:57-8:28) and in the conservative group 9 hours 8 minutes (5:06-13:16) (P < 0.001). The rate of EPDS >12 was 20% in the active arm versus 15% among controls (OR 1.26, 95% CI 0.7-2.2). There was one perinatal death in each group and no major differences in perinatal outcomes. Among nulliparous women with primary dysfunctional labour, early use of oxytocin does not reduce caesarean section or short-term postnatal depression. However, it shortens labour considerably and may reduce operative vaginal deliveries.

A trial of amniotomy in a Palestinian hospital

SummaryThis randomised controlled trial of routine amniotomy was carried out in a developing country setting to investigate the effect of this common procedure on the duration of labour, intra-partum interventions and selected newborn and maternal outcomes. In a Jerusalem teaching hospital, 533 multiparous and 157 nulliparous low-risk women were randomised to either amniotomy or intent to conserve membranes. For multiparae, the median duration from randomisation to full dilatation was 95 and 160 min, respectively in the intervention and control arms (p < 0.001); for nulliparae it was 210 and 270 min, respectively (p < 0.001). In both groups, oxytocin was used less in the intervention arms (p < 0.001), and no difference in mode of delivery and immediate outcomes was detected. However, given the risks of this intervention and these study findings indicating an overall short duration of childbirth, amniotomy should be limited to cases of abnormal progress of labour.

The influence of the birthplace and models of care on midwifery practice for the management of women in labour

This paper will examine how the settings in which midwives practice (the birthplace) and models of care affect midwives' decision making during the management of labour. One-hundred-and-four independent, team and hospital based midwives and 100 low obstetric risk nulliparous women to whom labour care was provided were surveyed. These midwives and women resided in the Auckland metropolitan area of New Zealand. The majority of midwives who participated worked in models of care which provided women with continuity of carer and care, however, this was not found to influence the way the midwives provided labour care. Instead, practice was found to be relatively homogenous regardless of whether the midwives worked in independent, team, or hospital-based practice. The birthplace setting in which the labour care took place did influence midwifery practice. The majority of midwives provided labour care in large obstetric hospitals and identified practices dominated by the medical model of care. Practice was described as being influenced by intervention and the need for technology, however, this did not prevent the majority of women from perceiving they were actively involved in the decision making process and that they worked in partnership with their midwives. Closer examination of the midwives' decision making processes whilst providing the labour care revealed that the midwives' individual decisions were influenced by the needs of the women rather than the hospital protocols. What became evident was that the midwives in this study had adopted a humanistic approach to care whereby technology was used alongside relationship-centred care.

Maternal complications of pregnancy increase beyond 40 weeks of gestation in low-risk women

We sought to determine when rates of maternal pregnancy complications increase for low-risk nulliparous and multiparous women at term. We designed a retrospective cohort study of low-risk women delivered beyond 37 weeks gestational age from 1976 to 2001. Rates of mode of delivery and maternal complications of labor and delivery were examined by gestational age with both bivariate and multivariate analyses. Statistical significance was designated by P<0.05. We found that among the 32,828 low-risk women who delivered at 37 completed weeks and beyond, the rates of primary cesarean delivery, operative vaginal delivery, third- or fourth-degree perineal lacerations, and chorioamnionitis all increased at 40 weeks of gestation (P<0.001), and the rate of postpartum hemorrhage increased at 41 weeks of gestation (P<0.001). These increases of rates of complications were larger and increased at an earlier gestational age among nulliparous women. We found that the risk of maternal complications for otherwise low risk nulliparous and multiparous women increased as pregnancy progressed beyond 40 weeks of gestation. Counseling of women who progress past their EDC should include comparing the risks of induction of labor to that of expectant management.

Impact of early admission in labor on method of delivery

Objective The effect of the timing of admission in labor unit on the method of delivery was evaluated in a cohort study. Method Four hundred and sixty six low-risk nulliparous women who were admitted in the labor unit in latent phase (group 1) were compared with 329 parturient women who were admitted in the active phase (group 2) to determine rate of and reasons for cesarean section, cervical dilation at the time of cesarean, and the rate of labor augmentation. Result The number of cesarean deliveries in group 1 was greater than that in the group 2 (301 vs 80, p < 0.0001 ). The main reason for cesarean section in group 1 was dystocia, and in 2, fetal distress. The rate of cesarean section in the women who were augmented was greater in group 1 than in group 2 (54% vs 23%, p < 0.0001). Conclusion Later admission in labor increases the rate of spontaneous vaginal delivery in low risk nulliparous women.

The Effect of Unrestricted Oral Carbohydrate Intake on Labor Progress

To determine if unrestricted oral carbohydrate intake during labor reduced the incidence of dystocia in low-risk nulliparous women. A randomized clinical trial at a university-affiliated hospital in southeastern Ontario. Low-risk nulliparous women were randomized between 30 and 40 weeks gestation to either an intervention or usual care group. Women in the intervention group received, prenatally, guidelines about food and fluid intake during labor and were encouraged to eat and drink as they pleased during labor. Women in the usual care group received no prelabor information and were restricted to ice chips and water during labor in the hospital. The incidence of dystocia, defined as a cervical dilatation rate of less than 0.5 cm/hr for a period of 4 hrs after a cervical dilatation of 3 cm. Three hundred twenty-eight women were randomized to the intervention (n = 163) or usual care (n = 165) groups. Women in the intervention group reported a significantly different pattern of oral intake during early labor in the hospital (chi(2) = 40.7, p < .001). The incidence of dystocia was 36% (n = 58) in the intervention group and 44% (n = 72) in the usual care group and was not significantly different (OR = 0.71, 95% CI = 0.46, 1.11). There were no significant differences in the other secondary outcomes or in the incidence of adverse maternal or neonatal complications. Eating and drinking early in labor had no significant impact on the incidence of dystocia and/or adverse maternal or neonatal outcomes.

Efeito de técnicas fisioterápicas sobre os desconfortos músculo-esqueléticos da gestação

PURPOSE: to study the effects of physiotherapeutic techniques applied by the Multidisciplinary Program of Preparation for the Childbirth and Maternity on musculoskeletal discomforts during pregnancy. METHODS: prospective cohort study, with 71 low-risk nulliparous women, distributed according to participation (study: n=38) or not (control; n=33). The Multidisciplinary Program of Preparation for Childbirh and Maternity had 10 meetings (18th to 38th week), with educational, physiotherapeutic, and interaction activities. Occurrence, characteristics, and evolution of musculoskeletal discomforts were compared by means of a specific questionnaire, both at the beginning and at the end of the program. The average of results of the initial assessment was compared through analysis of variance (ANOVA) followed by the F test. For the study between proportions in the beginning and at the end of the program the c2 was used. The statistical significance was determined at 5% of limit (p<0.05). RESULTS: at the beginning of the program, 63.6% of the pregnant women of the control group and 84.2% of the study group reported musculoskeletal symptoms (p=0.05), characterized by back and posterior pelvic pain. In the control group, light intensity (18.2%) and serious intensity pain (18.4) were predominant, while in the study group, the serious was 36.8%, and the isolated or associated was 31.6%. At the end, the control group showed symptoms of serious intensity (60.6%), with daily frequency (42.4%) and length of more than 3 h (69.7%; p<0.05). The study group reported light intensity (57.9%) and bimonthly frequency (50.0%) with a maximum length of one hour (55.3%) (p<0.05). Symptom evolution was also differentiated and there were worsening in 63.6% of pregnant women of the control group and improvement in 65.8% of participants of the program (p<0.05). CONCLUSIONS: the physiotherapeutic techniques of the Multidisciplinary Program of Preparation for Childbirth and Maternity were related to a decrease in intensity, frequency and length and to a better evolution of musculoskeletal discomforts during pregnancy.

Influence of the subpubic arch angle on anal sphincter trauma and anal incontinence following childbirth.

To assess the relationship between the subpubic arch angle, anal sphincter and perineal trauma, and anal incontinence after childbirth in nulliparous women. Prospective cohort study. University teaching hospital. One hundred thirty-four low risk nulliparous women. Measurements of the bony pelvic outlet were made to calculate the subpubic arch angle. Endosonographic assessment of the perineum and anal sphincter was made before and after delivery. A specific bowel function questionnaire was completed before and after delivery. Perineal and anal sphincter trauma, and deteriorating anal continence after delivery. Thirty-two women with a subpubic arch angle of less than 90 degrees had significantly prolonged first and second stages of labour when compared with 102 women whose subpubic arch was wider. Following delivery, anal continence deteriorated in more women with a narrow subpubic angle (69% vs 21%, P < 0.001) but this was unrelated to the incidence of anal sphincter and perineal trauma. A narrow subpubic arch is strongly associated with prolonged labour and postpartum anal incontinence in nulliparous women. However, perineal and anal sphincter trauma, assessed by ultrasound, does not account for the higher rate of postpartum analincontinence in women with a narrow subpubic arch angle.

Influence of the subpubic arch angle on anal sphincter trauma and anal incontinence following childbirth

Objective To assess the relationship between the subpubic arch angle, anal sphincter and perineal trauma, and anal incontinence after childbirth in nulliparous women. Design Prospective cohort study. Setting University teaching hospital. Sample One hundred thirty-four low risk nulliparous women. Methods Measurements of the bony pelvic outlet were made to calculate the subpubic arch angle. Endosonographic assessment of the perineum and anal sphincter was made before and after delivery. A specific bowel function questionnaire was completed before and after delivery. Main outcome measures Perineal and anal sphincter trauma, and deteriorating anal continence after delivery. Results Thirty-two women with a subpubic arch angle of less than 90° had significantly prolonged first and second stages of labour when compared with 102 women whose subpubic arch was wider. Following delivery, anal continence deteriorated in more women with a narrow subpubic angle (69% vs 21%, P < 0.001) but this was unrelated to the incidence of anal sphincter and perineal trauma. Conclusions A narrow subpubic arch is strongly associated with prolonged labour and postpartum anal incontinence in nulliparous women. However, perineal and anal sphincter trauma, assessed by ultrasound, does not account for the higher rate of postpartum anal incontinence in women with a narrow subpubic arch angle.

Second and third trimester Doppler P75Uterine artery Doppler velocimetry in low risk nulliparous women

BackgroundThe aim of this study was to assess how placental position and gestational age can influence the value of a diastolic notch of the uterine arteries as a screening test for pre‐eclampsia, in a low risk population of healthy nulliparous women.MethodsColor Doppler ultrasound was used to examine both uterine arteries in 654 healthy nulliparas at four‐weekly intervals between 20 and 32 weeks (wks). The only criterion for an abnormal result was the presence of an early diastolic notch. In each subject the placental position was also recorded.ResultsTwenty‐one out of 654 women developed pre‐eclampsia (3.2%). The sensitivity of the test becomes lower as gestational age advances and ranged from 81% at 20 wks, to 71.4% at 32 wks. In contrast the specificity and positive predictive value increase significantly. Eleven out of 12 women who delivered before 34 wks had abnormal waveforms at 24 wks. In women with a full lateral placenta the predictive value of the test was extremely low.ConclusionPre‐eclampsia can be more accurately predicted if along with the presence of a notch, both gestational age and placental position are taken into account.

Preeclampsia prevention: Lessons from the low-dose aspirin therapy trials

The ability of low-dose aspirin therapy to prevent preeclampsia is controversial. The 19 randomized, placebo-controlled trials of low-dose aspirin therapy reported in the literature were categorized according to the risk factors of the women studied–nulliparity, underlying medical illness, poor obstetric history, and multiple gestation. Low-dose aspirin therapy reduced the incidences of preeclampsia among women with poor obstetric histories and among high-risk nulliparous women but was ineffective among women with underlying medical illness. It was marginally effective among low-risk nulliparous women, and benefits for women with multiple gestations are unclear. More research is needed to better identify high-risk nulliparous women who might benefit from the use of low-dose aspirin therapy and to define potential benefits for women with multiple gestations. The differential effects of low-dose aspirin therapy in the various risk groups are probably a result of varying roles in the groups of abnormal arachidonic acid metabolism in mediating preeclampsia. It is premature to abandon the use of low-dose aspirin therapy for preeclampsia prevention. (Am J Obstet Gynecol 2000;183:523-8.)

Oral evening primrose oil:: Its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women

Evening primrose oil is widely used by many midwives to hasten cervical ripening in an effort to shorten labor and decrease the incidence of postdates pregnancies. Although its efficacy has been studied in the relief of symptoms of a number of medical conditions, its use has not been well studied, if at all, for the purpose of cervical ripening. The purpose of this study was to investigate the effect of oral evening primrose oil on the length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women. A two group retrospective quasi-experimental design conducted on a sample of women who received care in a birth center, compared selected outcomes of 54 women taking evening primrose oil in their pregnancy with a control group of 54 women who did not. Findings suggest that the oral administration of evening primrose oil from the 37th gestational week until birth does not shorten gestation or decrease the overall length of labor. Further, the use of orally administered evening primrose oil may be associated with an increase in the incidence of prolonged rupture of membranes, oxytocin augmentation, arrest of descent, and vacuum extraction.