Discontinuation Of Oxytocin Research Articles

Continued versus discontinued oxytocin stimulation in the active phase of labour (CONDISOX): individual management based on artificial intelligence - a secondary analysis

BackgroundCurrent guidelines regarding oxytocin stimulation are not tailored to individuals as they are based on randomised controlled trials. The objective of the study was to develop an artificial intelligence (AI) model for individual prediction of the risk of caesarean delivery (CD) in women with a cervical dilatation of 6 cm after oxytocin stimulation for induced labour. The model included not only variables known when labour induction was initiated but also variables describing the course of the labour induction.MethodsSecondary analysis of data from the CONDISOX randomised controlled trial of discontinued vs. continued oxytocin infusion in the active phase of induced labour. Extreme gradient boosting (XGBoost) software was used to build the prediction model. To explain the impact of the predictors, we calculated Shapley additive explanation (SHAP) values and present a summary SHAP plot. A force plot was used to explain specifics about an individual’s predictors that result in a change of the individual’s risk output value from the population-based risk.ResultsAmong 1060 included women, 160 (15.1%) were delivered by CD. The XGBoost model found women who delivered vaginally were more likely to be parous, taller, to have a lower estimated birth weight, and to be stimulated with a lower amount of oxytocin. In 108 women (10% of 1060) the model favoured either continuation or discontinuation of oxytocin. For the remaining 90% of the women, the model found that continuation or discontinuation of oxytocin stimulation affected the risk difference of CD by less than 5% points.ConclusionIn women undergoing labour induction, this AI model based on a secondary analysis of data from the CONDISOX trial may help predict the risk of CD and assist the mother and clinician in individual tailored management of oxytocin stimulation after reaching 6 cm of cervical dilation.

Outcome of Inducing Labor in Pregnancies with Suspected Fetal Growth Restriction: Oxytocin Discontinuation during the Active Phase of Labor versus Conventional Management.

Although fetal growth restriction (FGR) is associated with an increased risk of cesarean delivery during induced labor, there is limited evidence to guide labor management. This study aimed to investigate the prognosis of induced labor in pregnancies with suspected FGR and whether oxytocin discontinuation during the active phase of labor affects maternal and neonatal outcomes. This retrospective cohort study investigated singleton pregnancies with vertex presentation and indications for labor induction owing to FGR after 34.0 weeks of gestation at Osaka University Hospital. From January 2010 to December 2013, women were conventionally managed, and oxytocin was continued until delivery unless there was an indication for discontinuation (conventional management group). From January 2013 to December 2020, oxytocin was routinely discontinued, or the dose was reduced at the beginning of the active phase of labor (oxytocin discontinuation group). A total of 161 women (conventional management group, n = 74; oxytocin discontinuation group, n = 87) were included. After the active phase of induced labor, the total incidence of cesarean delivery was very low (3.1%), and the duration was short (173 ± 145 minutes). Oxytocin discontinuation was associated with lower cesarean delivery (1.1 vs. 5.4%; p = 0.12) and uterine tachysystole (9.8 vs. 23.0%; p = 0.08) rates and longer duration of the second stage of labor (mean: 56.5 ± 90 vs. 34.2 ± 45 minutes; p = 0.08) than conventional management; however, the difference was not significant. The other maternal and neonatal outcomes, including postpartum hemorrhage, did not also significantly differ between them. After the active phase of induced labor for suspected FGR, the risk of cesarean delivery is low, and the high incidence of uterine tachysystole and rapid labor progression should be considered cautiously. Oxytocin can be safely discontinued during the active phase of labor in women undergoing labor induction for FGR without an increased risk of cesarean delivery or other unfavorable outcomes. · The cesarean delivery rate was low after the active phase.. · The labor progress after the active phase was rapid.. · Oxytocin can be safely discontinued during the active phase..

Discontinuation of Oxytocin in the Second Stage of Labor and its Association with Postpartum Hemorrhage.

The objective of the study was to evaluate whether patients with oxytocin discontinued during the second stage of labor (≥30 minutes prior to delivery) had a lower rate of postpartum hemorrhage (PPH) compared with those with oxytocin continued until delivery or discontinued <30 minutes prior to delivery. Retrospective cohort study was performed from August 1, 2014 to July 31, 2019. Singleton pregnancies of 24 to 42 weeks gestation were included if they reached the second stage of labor and received oxytocin during labor. Patients on anticoagulants were excluded. Patients with oxytocin discontinued ≥30 minutes prior to delivery represented STOPPED and those with oxytocin continued until delivery or discontinued <30 minutes prior to delivery represented CONTINUED. Patient data were abstracted from the electronic medical record. The primary outcome was PPH (≥1,000 mL blood loss). Univariable analyses were performed to compare groups. Multi-variable logistic regression was performed to adjust for prespecified confounders. Planned sub-group analyses by the route of delivery were performed. Of 10,421 total patients, 1,288 had oxytocin STOPPED and 9,133 had oxytocin CONTINUED. There were no significant differences in age, race, or ethnicity, body mass index, public insurance, gestational diabetes, or pregnancy-induced hypertension between STOPPED and CONTINUED. The PPH rate was 15.2 and 5.7% in STOPPED and CONTINUED, respectively (p < 0.001). After adjusting for confounders, STOPPED remained at higher odds for PPH (adjusted odds ratio 2.859, 95% confidence interval 2.394, 3.414, p < 0.001). Among cesarean deliveries only, there was no significant difference in the rate of PPH between STOPPED and CONTINUED (38.0 vs. 36.4%, respectively, p = 0.730). However, among vaginal deliveries, the rate of PPH was actually lower in STOPPED than CONTINUED (3.4 vs. 5.2%, respectively, p = 0.024). The rate of PPH was higher in patients with oxytocin STOPPED compared with CONTINUED. However, among vaginal deliveries, there was a significantly lower rate of PPH in STOPPED. These disparate findings may be explained by the variable impact of second-stage oxytocin on PPH as a function of delivery type. · It is unclear if oxytocin use in the second stage of labor may independently increase the risk of hemorrhage.. · Patients with oxytocin discontinued during the second stage of labor had a higher rate of PPH.. · PPH was significantly lower among vaginal deliveries in patients with oxytocin discontinued..

Continued versus discontinued oxytocin after the active phase of labor: An updated systematic review and meta-analysis.

To systematically assess the effect of discontinued vs continued oxytocin after active stage of labour is established. Pubmed, Embase, and the Cochrane Library were systematically searched to 18 April 2021. The risk ratio or mean difference with corresponding 95% confidence interval were computed to investigate the effect of intervention or control on maternal and fetus outcomes. This review was registered in the International Prospective Register of Systematic Reviews: CRD42021249635. Discontinuing oxytocin when the active labour was established might decrease the risk of cesarean delivery [RR (95% CI): 0.84 (0.72-0.98), P = 0.02]. However, when we restricted our analysis to women who performed cesarean section after the active phase was reached, the difference was no longer significant [RR (95% CI): 0.82 (0.60-1.10), P = 0.19]. The incidence of uterine tachysystole [RR (95% CI): 0.36 (0.27-0.49)], postpartum hemorrhage [RR (95% CI): 0.78 (0.65-0.93)], and non-reassuring fetal heart rate [RR (95% CI): 0.66 (0.58-0.76)] were significantly lower in the oxytocin discontinuation group. We also found a possible decrease in the risk of chorioamnionitis in discontinued oxytocin group [RR (95% CI): 2.77 (1.02-5.08)]. An increased duration of active [MD (95% CI): 2.28 (2.86-41.71)] and second [MD (95% CI): 5.36 (3.18-7.54)] phase of labour was observed in discontinued oxytocin group, while the total delivery time was not significantly different [MD (95% CI): 20.17 (-24.92-65.26)]. After the active labor is reached, discontinuation of oxytocin could be considered a new recommendation for the improved maternal and fetal outcomes without delaying labour.

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CONDISOX- continued versus discontinued oxytocin stimulation of induced labour in a double-blind randomised controlled trial

BackgroundOxytocin is an effective drug for induction of labour, but is associated with serious adverse effects of which uterine tachysystole, fetal distress and the need of immediate delivery are the most common. Discontinuation of oxytocin once the active phase of labour is established could reduce the adverse effects.The objective is to investigate how the caesarean section rate is affected when oxytocin stimulation is discontinued in the active phase of labour compared to labours where oxytocin is continued.MethodsCONDISOX is a double-blind multicentre randomised controlled trial conducted at Danish and Dutch Departments of Obstetrics and Gynaecology. The first participant was recruited on April 8 2016.Based on a clinically relevant relative reduction in caesarean section rate of 7%, an alpha of 0.05, a beta of 80%, we aim for 1200 participating women (600 in each arm).The CONDISOX trial includes women at a gestational age of 37–42 complete weeks of pregnancy, who have uterine activity stimulated with oxytocin infusion for the induction of labour. Women are randomised when the active phase of labour becomes established, to study medication containing either oxytocin (continuous group) or placebo (discontinued group) infusion. Women are stratified by birth site, indication for oxytocin stimulation (induction of labour, prelabour rupture of membranes) and parity (nulliparous, parous +/− previous caesarean section).We will compare the primary outcome, caesarean section rate, in the two groups using a chi-square test with a p-value of 0.05. If superiority is not demonstrated, we have a pre-defined post hoc non-inferiority boundary (margin, delta) at 1.09.Secondary outcomes include duration of the active phase of labour, incidence of uterine tachysystole, postpartum haemorrhage, admission to the neonatal intensive care unit, Apgar score, umbilical arterial blood pH, and birth experience.DiscussionThe high frequency of oxytocin use and the potential risks of both maternal and fetal adverse effects of oxytocin emphasise the need to determine the optimal oxytocin regime for induction of labour.Trial registrationNCT02553226 (registered September 17, 2015). Eudra-CT number: 2015–002942-30.

Discontinuation of intravenous oxytocin in the active phase of induced labour.

Discontinuation of intravenous oxytocin in the active phase of induced labour.

Oxytocin discontinuation after the active phase of induced labor: A systematic review

BackgroundOxytocin is the most widely used drug in the induction of labor, but it could have potential adverse effects that derive from uterine hyperstimulation. AimTo determine the benefits and drawbacks of oxytocin continuation versus oxytocin discontinuation after the active phase of induced labor. MethodsWe systematically searched Pubmed, EMBASE, Scopus, ClinicalTrials.gov and Cochrane Library Plus until October 2017, for randomized controlled trials comparing oxytocin continuation with oxytocin discontinuation when the active phase of labor is reached were included. Data was collected by three reviewers and quality of the included studies assessed using the methodology recommended in the Cochrane Handbook. StatsDirect software was used to calculate risk ratios for binary variables and weighted mean differences for continuous variables. A fixed-effects or random-effects model was used as appropriate. ResultsNine studies were selected including 1538 women, 774 in the oxytocin continuation group and 764 in the oxytocin discontinuation group. The incidence of cesarean sections (14.3% vs. 8.6%; relative risk, 1.67; 95% confidence interval: 1.25–2.23), uterine hyperstimulation (12.4% vs. 4.7%; relative risk, 2.59; 95% confidence interval: 1.70–3.93) and nonreassuring fetal heart rate (19.2% vs.12.5%; relative risk, 1.55; 95% confidence interval: 1.18–2.02) were significantly higher in the oxytocin continuation group. An increase in the duration of the second stage of labor in the oxytocin discontinuation group was observed (pooled mean difference, −7.03; 95% confidence interval: −9.80 to −4.26). ConclusionsAfter the active phase of induced labor, oxytocin continuation increases the risk of cesarean section, uterine hyperstimulation and alterations to the fetal heart rate.

Discontinuing Oxytocin Infusion in the Active Phase of Labor: A Systematic Review and Meta-analysis.

To evaluate the benefits and harms of discontinuation of oxytocin after the active phase of labor is reached. Electronic databases (ie, MEDLINE, Scopus, ClinicalTrials.gov, EMBASE, ScienceDirect, the Cochrane Library at the CENTRAL Register of Controlled Trials, Scielo) were searched from their inception until April 2017. We included all randomized controlled trials comparing discontinuation (ie, intervention group) and continuation (ie, control group) of oxytocin infusion after the active phase of labor is reached, either after induction or augmentation of labor. Discontinuation of oxytocin infusion was defined as discontinuing oxytocin infusion when the active phase of labor was achieved. Continuation of oxytocin infusion was defined as continuing oxytocin infusion until delivery. Only trials in singleton gestations with vertex presentation at term were included. The primary outcome was the incidence of cesarean delivery. Nine randomized controlled trials, including 1,538 singleton gestations, were identified as relevant and included in the meta-analysis. All nine trials included only women undergoing induction of labor. In the discontinuation group, if arrest of labor occurred, usually defined as no cervical dilation in 2 hours or inadequate uterine contractions for 2 hours or more, oxytocin infusion was restarted. Women in the control group had oxytocin continued until delivery usually at the same dose used at the time the active phase was reached. Women who were randomized to have discontinuation of oxytocin infusion after the active phase of labor was reached had a significantly lower risk of cesarean delivery (9.3% compared with 14.7%; relative risk 0.64, 95% CI 0.48-0.87) and of uterine tachysystole (6.2% compared with 13.1%; relative risk 0.53, 95% CI 0.33-0.84) compared with those who were randomized to have continuation of oxytocin infusion until delivery. Discontinuation of oxytocin infusion was associated with an increase in the duration of the active phase of labor (mean difference 27.65 minutes, 95% CI 3.94-51.36). In singleton gestations with cephalic presentation at term undergoing induction, discontinuation of oxytocin infusion after the active phase of labor at approximately 5 cm is reached reduces the risk of cesarean delivery and of uterine tachysystole compared with continuous oxytocin infusion. Given this evidence, discontinuation of oxytocin infusion once the active stage of labor is established in women being induced should be considered as an alternative management plan.

Practice variation in the management of intrapartum fetal distress in The Netherlands and the Western world

ObjectiveSolid evidence on the effect of intrauterine resuscitation on neonatal outcome is limited, and superiority of one intervention over the others is not clear. We therefore surveyed the clinical practice variation in fetal monitoring and the management of fetal distress during labor, in Dutch labor wards. In addition, we have compared recommendations from international guidelines. Study designWe conducted a survey among all 86 Dutch hospitals, using a questionnaire on fetal monitoring and management of fetal distress. In addition, we requested international guidelines of 28 Western countries to study international recommendations regarding labor management. ResultsThe response rate of the national survey was 100%. Labor wards of all hospitals use CTG for fetal monitoring, 98% use additional fetal scalp blood sampling, and 23% use ST-analysis. When fetal distress is suspected, oxytocin is discontinued and tocolytic drugs are applied in all hospitals. Nearly all hospitals (98%) use maternal reposition for fetal resuscitation, 33% use amnioinfusion, and 58% provide maternal hyperoxygenation. Management is mainly based on the Dutch national guideline (58%) or on local guidelines (26%).Eight international guidelines on fetal monitoring were obtained for analysis. Fetal scalp blood sampling facilities are recommended in all the obtained guidelines. Use of ST-analysis is recommended in three guidelines and advised against in three guidelines. Five guidelines also advised on intrauterine resuscitation: discontinuation of oxytocin and use of tocolytic drugs was advised in all guidelines, amnioinfusion was recommended in two guidelines and advised against in two guidelines, whereas maternal hyperoxygenation was recommended in two guidelines and advised against in one guideline. ConclusionNationwide clinical practice, and recommendations from international guidelines agree on the use of fetal scalp blood sampling in addition to cardiotocography during labor. The opinion on the use of ST-analysis differs per clinic and per guideline. Discontinuation of oxytocin, administration of tocolytic drugs and maternal repositioning are rather uniform, on national and international level. However, there is a large variation in the use of amnioinfusion and maternal hyperoxygenation, which may be explained by the contradictory recommendations of the different guidelines.

Discontinuation of intravenous oxytocin in the active phase of induced labour

Background In most Western countries, obstetricians and midwives induce labour in about 25% of pregnant women. Oxytocin is an effective drug for this purpose, but associated with serious adverse effects of which uterine tachysystole, fetal distress and the need for immediate delivery are the most common. Various administration regimens such as reduced or pulsatile dosing have been suggested to minimise these. Discontinuation in the active phase of labour, i.e. when contractions are well‐established and the cervix is dilated at least 5 cm is another method which may reduce adverse effects.

Cesarean Section Rate in Oxytocin Infusion between Continuous Until Delivery and Discontinuation at Active Phase of Labor: a Randomized Controlled Study

Objective: To compare the cesarean section rate between discontinuing oxytocin infusion for labor induction or augmentation when the active phase of labor is established and continuing oxytocin infusion until delivery. Materials and methods: This was a prospective randomized controlled trial of 340 pregnant women who underwent labor induction or augmentation at Bhumibol Adulyadej Hospital during February 2014 to January 2015. Parturient were randomly and equally allocated into two groups. The continued group received oxytocin infusion throughout all stages of labor. The discontinued group received oxytocin infusion and early discontinued when the active phase of labor had begun. Intention to treat analysis was used in this study. Results: Three hundred and forty pregnant women were enrolled for the study. They were assigned randomly into two groups, 170 patients for each group. Cesarean section rate in continued and discontinued group were 31.8% and 27.7%, respectively ( p = 0.40). The infusion of intravenous fluid in CG group was stopped due to non-reassuring fetal heart rate pattern in 15 women and total oxytocin doses used were significantly higher than that in DG group. In DG group, additional oxytocin was required due to poor uterine contraction. Duration of each stage of labor, maternal complications and adverse neonatal outcomes were not significantly different. There were only two cases of postpartum hemorrhage in discontinued group that was successful managed by medical treatment. Conclusion: There was not sufficient evidence to support whether discontinuation or continuation of oxytocin in active phase of labor influenced cesarean section rate. However, higher doses of oxytocin used was found in continuation group. Future well-randomized design with enough sample size is needed.

Ventricular tachycardia observed during cesarean section in a patient without structural cardiac disease.

A 32-year-old gravida 2, para 1 woman without structural cardiac disease was scheduled for her second cesarean section under combined spinal and epidural anesthesia (CSEA). She had stable hemodynamics after delivery; however, 16 min after the application of uterotonics, ventricular tachycardia (VT) with a heart rate (HR) of 150 bpm appeared. VT lasted for <30 s, and her hemodynamics remained stable. Ventricular arrhythmia frequently appeared for 3 min, and the HR at sinus rhythm was approximately 90 bpm. After the discontinuation of oxytocin, VT did not reappear. A postoperative 12-lead electrocardiogram showed first-degree atrioventricular block, but echocardiography performed 2 days later did not reveal any structural abnormalities. Autonomic nervous imbalance induced by CSEA, ephedrine, and oxytocin, as well as ergometrine may cause intraoperative VT during cesarean section in patients without structural cardiac disease.

Stopping Oxytocin in Active Labor Rather Than Continuing it until Delivery: A Viable Option for the Induction of Labor.

Induction of labor (IOL), using intravenous oxytocin, is the artificial initiation of labor before its spontaneous onset for the purpose of delivery of the fetoplacental unit. Although there are various studies looking at dosages of oxytocin, only a few have addressed the issue of discontinuation of oxytocin in the active stage of labor. Thus, our study was conducted to evaluate the need for continuation versus discontinuation of oxytocin during active labor. This prospective, randomized controlled trial included 106 women who needed IOL. Oxytocin infusion was initiated at a rate of 3mIU/min and was incremental until 4-6cm cervical dilation. At this point the patients were randomly assigned into one of two groups. In group one, oxytocin was discontinued, and infusion was continued with 0.9% sodium chloride solution. In group two, oxytocin was continued at the same dose until delivery. The duration of oxytocin infusion was 5.5 hours in the oxytocin discontinuation group and 11.0 hours in oxytocin continuation group (p<0.001). The total dose of oxytocin was significantly higher in group two (6.1 units vs. 16.5 units; p=<0.001). The induction-delivery interval was significantly less in group one (9.1 and 11.2 hours in group one and group two, respectively; p=0.023). Oxytocin discontinuation in the active stage of labor did not prolong the active stage. The total duration of labor and total oxytocin dose were significantly less in the oxytocin discontinuation group. Our results suggest that oxytocin discontinuation is an alternative and viable option particularly in resource poor and economically challenged settings. It not only reduces the need for intense monitoring and prolonged oxytocin use-associated dangers but reduces the total cost of labor management.

Effect of oxytocin discontinuation during the active phase of labor

Objective: To observe the progression of labor when oxytocin use is limited to the onset of the active stage of labor.Methods: A randomized, prospective controlled study was performed to address the issue of oxytocin infusion after the onset of active labor in 140 patients. In the study group, infusion of oxytocin was discontinued at the onset of the active phase of labor, which was accepted as a cervical dilatation of 5 cm. In the control group, incremental oxytocin infusion was administered until 5 cm cervical dilatation, and then was maintained at the same level until delivery.Results: The primary outcome variable was duration from the beginning of the active phase to delivery. In the study group, the duration of the active phase of labor was about 30 min longer than in the control group and this difference was significant. The secondary outcomes of the study were maternal–fetal complications of oxytocin and in both groups there were no significant differences.Conclusion: It is not reasonable to discontinue oxytocin infusion at the beginning of active labor. Nevertheless, for an accurate conclusion expanded investigations are needed.

Intranasal oxytocin in the treatment of autism spectrum disorders: A review of literature and early safety and efficacy data in youth

BackgroundThere is a paucity of treatments targeting core symptom domains in Autism Spectrum Disorder (ASD). Several animal models and research in typically developing volunteers suggests that manipulation of the oxytocin system may have therapeutic potential for the treatment of social deficits. We review the literature for oxytocin and ASD and report on early dosing, safety and efficacy data of multi-dose oxytocin on aspects of social cognition/function, as well as repetitive behaviors and co-occurring anxiety within ASD. Methods: Fifteen children and adolescents with verbal IQs≥70 were diagnosed with ASD using the ADOS and the ADI-R. They participated in a modified maximum tolerated dose study of intranasal oxytocin (Syntocinon). Data were modeled using repeated measures regression analysis controlling for week, dose, age, and sex. Results: Among 4 doses tested, the highest dose evaluated, 0.4IU/kg/dose, was found to be well tolerated. No serious or severe adverse events were reported and adverse events reported/observed were mild to moderate. Over 12 weeks of treatment, several measures of social cognition/function, repetitive behaviors and anxiety showed sensitivity to change with some measures suggesting maintenance of effect 3 months past discontinuation of intranasal oxytocin. Conclusions: This pilot study suggests that daily administration of intranasal oxytocin at 0.4IU/kg/dose in children and adolescents with ASD is safe and has therapeutic potential. Larger studies are warranted.This article is part of a Special Issue entitled Oxytocin and Social Behav.

Oxytocin Discontinuation During Active Labor in Women Who Undergo Labor Induction

Objective The purpose of this study was to determine whether there is an increase in the cesarean delivery rate in women who undergo induction when oxytocin is discontinued in the active phase of labor. Study Design We conducted a prospective randomized controlled trial of women who underwent induction of labor at term; they were assigned randomly to either routine oxytocin use (routine) or oxytocin discontinuation (DC) once in active labor. Analysis was by intention to treat. Results Two hundred fifty-two patients were eligible for study analysis: 127 patients were assigned randomly to the routine group and 125 patients were assigned randomly to the DC group. Cesarean delivery rate was similar between the groups (routine, 25.2% [n = 32] vs the DC group, 19.2% [n = 24]; P = .25). There was a higher chorioamnionitis rate and slightly longer active phase in those women who were assigned to the DC group. In adjusted analysis, the rate of chorioamnionitis was not different by randomization group but was explained by the duration of membrane rupture and intrauterine pressure catheter placement. Conclusion Discontinuation of oxytocin in active labor after labor induction does not increase the cesarean delivery rate significantly.

Oxytocin discontinuation during active labor in women who undergo labor induction

The purpose of this study was to determine whether there is an increase in the cesarean delivery rate in women who undergo induction when oxytocin is discontinued in the active phase of labor. We conducted a prospective randomized controlled trial of women who underwent induction of labor at term; they were assigned randomly to either routine oxytocin use (routine) or oxytocin discontinuation (DC) once in active labor. Analysis was by intention to treat. Two hundred fifty-two patients were eligible for study analysis: 127 patients were assigned randomly to the routine group and 125 patients were assigned randomly to the DC group. Cesarean delivery rate was similar between the groups (routine, 25.2% [n = 32] vs the DC group, 19.2% [n = 24]; P = .25). There was a higher chorioamnionitis rate and slightly longer active phase in those women who were assigned to the DC group. In adjusted analysis, the rate of chorioamnionitis was not different by randomization group but was explained by the duration of membrane rupture and intrauterine pressure catheter placement. Discontinuation of oxytocin in active labor after labor induction does not increase the cesarean delivery rate significantly.

Effects of Removing Cows from Chronic Oxytocin use During Lactation

The objectives of this study were to investigate the effect of discontinuation of chronic oxytocin supplementation on lactating dairy cows and to determine if there was a difference between methods of discontinuation. The study was conducted on a commercial dairy in central New York milking over 1,200 cows, with more than 80 cows being supplemented with oxytocin prior to the start of the study. Seventy-seven cows receiving supplemental oxytocin were enrolled in the study and randomly assigned to one of four treatment groups: 1) abrupt discontinuation; 2) abrupt discontinuation with a needle stick at the normal time of oxytocin injection; 3) graduated decrease in oxytocin dose; and 4) a control group that was only monitored. Total milk weight, milk in the first two minutes, total milking time, and bimodality of milk flow were measured at every milking for 12 milkings before and after the initiation of the treatment protocol. Non-parametric paired analysis was used within treatment group before and after initiation of treatment, and non-paired analysis was used to analyze differences between treatment groups. Other than the control group, all experimental groups showed a significant decrease in milk production per milking (P&lt;0.005), ranging from 2.8-7.4 lb (1.3-3.4 kg) per milking per cow. None of the cows ceased lactating. There were no significant differences in milk produced in the first two minutes, total milking time, or the number of bimodal milk flows in any of the groups (P&gt;0.09). No significant differences (P&gt;0.11) in the change in milk production per milking or milk produced in the first two minutes were found between the group that underwent graduated discontinuation of oxytocin and the group abruptly removed from oxytocin supplementation without sham injection. These results show that dairy producers can stop supplementing cows with exogenous oxytocin in the parlor by either abrupt discontinuation or a weaning protocol with a loss of milk similar to that gained from oxytocin supplementation, and cows will not cease to lactate.

Discontinuation of oxytocin in the active phase of labor

To show that early discontinuation of oxytocin will not increase the mean duration of the active labor phase in a clinically significant way. Controlled non-inferiority study. Department of Obstetrics and Gynecology, University of Caen, Clemenceau Hospital, France. A total of 138 women with singleton pregnancy and a vertex presentation of over 34 gestational weeks, presenting a medical indication of induction of labor or a dystocia at onset of labor, from May 2005 to June 2006. Two parallel groups were compared: continuation of oxytocin until delivery versus discontinuation of oxytocin at the onset of the active phase. The clinically acceptable increase in mean duration of the active phase of labor (non-inferiority margin) was set at 60 minutes. Primary outcome measure was duration of the active labor phase. Secondary outcome measures included total duration of labor, parameters concerning oxytocin use, rates of uterine hyperstimulation and fetal heart rate (FHR) abnormalities, and mode of delivery. Some neonatal outcomes were also analyzed. Equivalence of the two strategies (continuation vs. discontinuation of oxytocin) was not demonstrated (p=0.97 testing for non-inferiority), the active phase even being significantly longer by a mean of 113 minutes (p=0.0001 testing for superiority). The rates of cesarean sections, alterations of FHR and delivery hemorrhage were higher when oxytocin was continued, but not significantly. There were significantly more infants hospitalized in neonatology when oxytocin was continued (p=0.028). Discontinuation of oxytocin at the onset of the active phase prolongs labor. We found no argument for discontinuing the infusion of oxytocin at the onset of the active phase.