Delivery of vertex/nonvertex twins: did the horses already leave the barn?

[Delivery of twins : lessons learnt from the national observational prospective comparative study JUMODA]

OBJECTIVES

To summerize the results of the JUMODA study (JUmeaux MODe d'Accouchement) on the planned mode of delivery of twin pregnancy and the management of second twin delivery.

METHODS

JUMODA was a national observational prospective comparative study that took place between february 2014 and march 2015 in 176 french maternity units performing more than 1500 deliveries per year. Its main objectives were the comparison of neonatal and maternal morbidity according to the planned mode of delivery and the determination of the managements of second twin delivery associated with the best neonatal outcomes. To control for potential confounding factors and indication biases, statistical analyses comprized multivariate logistic regressions and matching on propensity scores.

RESULTS

The JUMODA study recruited 8823 women with twin delivery at or beyond 22 weeks of gestation. For twin pregnancies with a cephalic first twin at 32 weeks of gestation and beyond, severe neonatal morbidity was higher in the planned cesarean (150/2908 (5.2 %) than in the planned vaginal delivery group (199/8922 (2.2 %), aOR 1.56, 95 % CI 1.19-2.04). Increased neonatal morbidity in the planned cesarean delivery group was explained by higher severe morbidity in neonates born preterm (aOR 1.64, 95 % CI 1.13-2.39, for deliveries between 32+0 and 34+6 weeks of gestation, aOR 2.04, 95 % CI 1.22-3.41, for deliveries between 35+0 SA and 36+6 weeks of gestation) but not in neonates born at term (aOR 1.19, 95 % CI 0.58-2.44). In comparison with planned cesarean delivery, planned vaginal delivery was not associated with increased severe neonatal morbidity in case of breech presenting first twin after 32 weeks of gestation or with decreased survival witout severe neonatal morbidity in case of delivery before 32 weeks of gestation whatever the first twin presentation. In comparison with planned vaginal delivery, planned cesarean delivery was associated with increased severe maternal morbidity only in women aged 35 and higher. Delivery of non cephalic second twin was associated with similar severe neonatal morbidity rate than delivery of cephalic second twin. Finally, in case of cephalic second twin, internal version followed by total breech extraction was associated with less cesarean for the second twin but with higher severe neonatal morbidity in case of preterm birth in comparison with pushing efforts, ocytocin perfusion and artificial rupture of membranes.

CONCLUSIONS

Planned vaginal delivery is the planned mode of delivery to encourage for the majority of pregnant women with twins, whatever first twin presentation and gestational age at delivery. No management of cephalic second twin appears better than an other, its choice will rest on obstetrician preferences.

Retrospective evaluation of attempted vaginal deliveries in dichorionic twin pregnancies

Purpose

Numbers of planned cesarean deliveries are increasing in twin pregnancies, despite the lack of evidence for this approach, and the second twin is thought to be at risk for a poorer outcome. The aim of this study was to examine whether twins have a poorer outcome if an attempted vaginal delivery is changed to a cesarean section or combined delivery.

Methods

This retrospective data analysis included all women with dichorionic twin pregnancies attempting vaginal delivery over a 10-year period. Outcome parameters for the first and second twins relative to their mode of birth were compared. A correlation model between the interdelivery time interval and Apgar scores was calculated. Subgroup analyses assessing the birth mode of the first and second twins were conducted.

Results

A total of 248 women were enrolled in the study. The second twins had significantly lower values for outcome parameters, such as umbilical artery cord pH and Apgar scores in comparison with the first twins (P < 0.01). The subgroup analysis of birth modes in first and second twins showed a significantly poorer outcome in the cesarean section and combined delivery group (P < 0.05). The interdelivery time interval was significantly longer in the second twin cesarean section group (P < 0.01). There was no significant correlation between the interdelivery time intervals and Apgar scores (P > 0.05).

Conclusion

Although outcome parameters were significantly lower in second twins and twins born via secondary cesarean section, the clinical relevance of this appears to be negligible.

A Systematic Evaluation of Hospital Performance of Childbirth Delivery Modes and Associated Factors in the Friuli Venezia Giulia Region (North-Eastern Italy), 2005-2015

Cesarean sections (CS) have become increasingly common in both developed and developing countries, raising legitimate concerns regarding their appropriateness. Since improvement of obstetric care at the hospital level needs quantitative evidence, using routinely collected health data we contrasted the performance of the 11 maternity centres (coded with an alphabetic letter A to L) of an Italian region, Friuli Venezia Giulia (FVG), during 2005-15, after removing the effect of several factors associated with different delivery modes (DM): spontaneous vaginal delivery (SVD), instrumental vaginal delivery (IVD), overall CS (OCS) and urgent/emergency CS (UCS). A multivariable logistic regression model was fitted for each individual DM, using a dichotomous outcome (1 = each DM; 0 = rest of hospital births) and comparing the stratum specific estimates of every term with their respective reference categories. Results were expressed as odds ratios (OR) with 95% confidence intervals (95%CI). The Benjamini-Hochberg (BH) false discovery rates (FDR) approach was applied to control alpha error due to the large number of statistical tests performed. In the entire FVG region during 2005-2015, SVD were 75,497 (69.1% out of all births), IVD were 7,281 (6.7%), OCS were 26,467 (24.2%) and UCS were 14,106 (12.9% of all births and 53.3% out of all CS). SVD were more likely (in descending order of statistical significance) with: higher number of previous livebirths; clerk/employed occupational status of the mother; gestational age <29 weeks; placentas weighing <500 g; stillbirth; premature rupture of membranes (PROM). IVD were predominantly more likely (in descending order of statistical significance) with: obstructed labour, non-reassuring fetal status, history of CS, labour analgesia, maternal age ≥35 and gestation >40 weeks. The principal factors associated with OCS were (in descending order of statistical significance): CS history, breech presentation, non-reassuring fetal status, obstructed labour, multiple birth, placental weight ≥ 600 g, eclampsia/pre-eclampsia, maternal age ≥ 35 and oligohydramnios. The most important risk factors for UCS were (in descending order of statistical significance): placenta previa/abruptio placenta/ antepartum hemorrage; non-reassuring fetal status, obstructed labour; breech presentation; PROM, eclampsia/pre-eclampsia; gestation 33-36 weeks; gestation 41+ weeks; oligohydramnios; birthweight <2,500 g, maternal age ≥ 35 and cord prolapse. After removing the effects of all other factors, we found great variability of DM rates across hospitals. Adjusting for all risk factors, all hospitals had a OCS risk higher than the referent (hospital G). Out of these 10 hospitals with increased adjusted risk of OCS, 9 (A, B, C, D, E, F, I, J, K) performed less SVD and 5 (A, C, D, I, J) less IVD. In the above 5 centres CS was therefore probably overused. The present study shows that routinely collected administrative data provide useful information for health planning and monitoring. Although the overall CS rate in FVG during 2005-15 was 24.2%, well below the corresponding average Italian national figure (38.1%), the variability of DM rates across FVG maternity centres could be targeted by policy interventions aimed at reducing the recourse to unnecessary CS. In some clinical conditions such as obstructed labor, non-reassuring fetal status, breech presentation, history of CS, higher maternal age and multiple birth, consideration may be given to more conservative DM. The overuse of CS in nulliparas and repeat CS (RCS) should be carefully monitored and subject to audit.

Evaluation of a Quality Improvement Intervention to Increase Vaginal Birth for Twins

OBJECTIVE

To evaluate whether there was an association between the systematic promotion of twin vaginal delivery and an increase in the rates of twin vaginal birth.

METHODS

We conducted a retrospective cohort study. We implemented a quality improvement initiative promoting twin vaginal delivery at an academic tertiary care center in 2013. The program included a needs assessment, simulation of vaginal twin delivery, online educational material, and the expansion of a dedicated twin clinic. We analyzed rates of twin vaginal birth in pregnancies at or beyond 24 weeks of gestation without a contraindication to labor, prior uterine surgery, or a demise or lethal anomaly of either twin. Using linear regression, we calculated annual adjusted rates of twin vaginal birth from 2010 to 2015 and in the 3 years before and after our intervention. We performed an interrupted time-series analysis estimating rates of change before and after the intervention to account for the influence of secular trend.

RESULTS

Of 1,574 patients delivering twins, 897 (57%) were included, with 479 in the 3 years before and 418 in the 3 years after the intervention. Adjusted rates of vaginal delivery increased from 32.1% (n=153) to 44.2% (n=185) before and after the intervention (P<.01), with a decrease in elective cesarean delivery from 54.6% (n=479) to 44.3% (n=185) (P<.01). Rates of breech extraction increased after the intervention (5.7% vs 9.3%, P=.04). However, there was no difference in the rate of change in twin vaginal birth in the time period before (1.35% annual increase, P=.76) or after (5.8% annual increase, P=.40) the intervention.

CONCLUSIONS

Although we observed an increased rate of twin vaginal birth in the time period after our intervention, because the rates of increase before and after the intervention were not statistically different, the increase is not attributable to our intervention and is more properly attributed to secular trend.

Trial of labor after cesarean delivery in twin gestations: systematic review and meta-analysis

BACKGROUND

Trial of labor after cesarean is offered as a routine option for singleton gestations with previous cesarean delivery. However, adequate data are not available to determine whether the approach is equally valid in women with twin gestation.

OBJECTIVE

This systematic review and meta-analysis aimed to assess maternal morbidities associated with trial of labor after cesarean delivery in twin gestations.

STUDY DESIGN

Electronic databases were searched for cohort studies and randomized controlled trials evaluating the association between trial of labor after cesarean delivery in twin gestations and pregnancy outcomes. Maternal mortality and severe morbidities, such as uterine rupture and hysterectomy, were compared between women who had trial of labor and women who had a planned repeat cesarean delivery. Pooled odds ratios were calculated using a random-effects model. Additional analyses were performed to compare trial of labor after cesarean outcomes in singleton and twin gestations.

RESULTS

Eleven cohort studies including a total of 8209 twin gestations with previous cesarean delivery were included in the present study. Of these gestations, 2484 were intended for planned vaginal birth and 5725 were intended for planned repeat cesarean delivery. The rate of uterine rupture in twin gestations was higher in the trial of labor after cesarean group than the elective cesarean group (odds ratio, 10.09, 95% confidence interval, 4.30-23.69, I² = 68%). However, no statistically significant difference was found in the rate of uterine rupture between twin and single gestations attempting trial of labor after cesarean delivery (odds ratio, 1.34, 95% confidence interval, 0.54-3.31, I² = 0%). Women who attempted a trial of labor after cesarean delivery with twins did not have an increased risk of uterine scar dehiscence, hemorrhage, blood transfusion, or neonatal morbidity and mortality compared with elective repeat cesarean delivery. Patients with twins had similar rates of successful vaginal delivery as patients with singletons (odds ratio, 0.85, 95% confidence interval, 0.61-1.18, I² = 36%).

CONCLUSION

This meta-analysis demonstrates that, although trial of labor with twins after previous cesarean delivery is associated with higher rates of uterine rupture compared with elective cesarean delivery, pregnancy outcomes and success rates are similar to a trial of labor after previous cesarean delivery in singleton gestations. Planned vaginal birth for women with twin gestation and previous cesarean delivery may be a safe alternative to a planned repeat cesarean.

Neonatal morbidity associated with vaginal delivery of noncephalic second twins

BACKGROUND

Management of noncephalic second twin delivery rests on the results of population-based retrospective studies of twin births that have shown higher neonatal mortality and morbidity for second twins with noncephalic, compared with cephalic, presentations after vaginal delivery of the first twin. Because these studies are flawed by data of questionable validity, do not report the obstetrical practices at delivery, and do not allow collection of potential confounding variables, we performed a national prospective study specially designed to evaluate the management of twins' delivery.

OBJECTIVE

We sought to assess neonatal mortality and morbidity according to second twin presentation after vaginal birth of the first twin.

STUDY DESIGN

The Jumeaux Mode d'Accouchement study was a nationwide prospective population-based cohort study of twin deliveries performed in 176 maternity units in France from February 2014 through March 2015. The primary outcome was a composite of intrapartum mortality and neonatal mortality and morbidity. Neonatal outcomes of second twins born ≥32 weeks of gestation after vaginal delivery of the first cephalic or breech twin were compared according to the noncephalic or cephalic second twin presentation. Multivariable logistic regression models controlled for potential confounders. Subgroup analyses were conducted according to the breech or transverse presentation of the noncephalic second twin, and gestational age at delivery, before or after 37 weeks of gestation.

RESULTS

Among 3903 second twins enrolled in the study, 2384 (61.1%) were in cephalic and 1519 (38.9%) in noncephalic presentations, of whom 999 (25.6%) were in breech and 520 (13.3%) in transverse presentation. Composite neonatal mortality and morbidity did not differ between the noncephalic and cephalic group (47/1519 [3.1%] vs 59/2384 [2.5%]; adjusted odds ratio, 1.23; 95% confidence interval, 0.81-1.85). No significant difference between groups was shown for the primary outcome in subgroup analyses according to type of noncephalic second twin presentation or gestational age at delivery. Cesarean delivery rates for the second twin were lower in the breech than in the cephalic group (14/999 [1.4%] vs 75/2384 [3.1%], P = .003) and lower in the cephalic than in the transverse group (75/2384 [3.1%] vs 35/520 [6.7%], P < .001).

CONCLUSION

Noncephalic and cephalic second twin presentations after vaginal delivery of the first twin ≥32 weeks of gestation are associated with similar low composite neonatal mortality and morbidity. Vaginal delivery of noncephalic second twin is a reasonable option.

Mode of birth in twins: data and reflections

Our primary objective was to compare neonatal and maternal outcomes in women with twin pregnancies, beyond 32 weeks, having a planned vaginal birth or a planned caesarean section (CS). This was a retrospective cohort study from a single tertiary centre over nine years. 534 sets of twins ≥32 + 0 weeks of gestation were included. 401 sets were planned vaginally and 133 sets were planned by CS. We compared a composite adverse perinatal outcome (perinatal mortality or serious neonatal morbidity; five minute APGAR score ≤4, neurological abnormality and need for intubation) and a composite maternal adverse outcome (major haemorrhage, trauma or infection) between the groups. There were no significant differences. Given the similarity of these results with several other larger studies of twin birth, we sought to look at reasons why there is still a rising rate of CS for twin births. We further make suggestions for keeping this rate to a sensible minimum. Impact statement What is already known on this subject? The largest randomised controlled study comparing planned vaginal birth with planned CSs for lower risk twins between 32 and 39 weeks of gestation, showed no added safety from planned CS. However, in most of the Western countries this conclusion has failed to increase the number of planned vaginal births for lower risk twins. What do the results of this study add? This observational study from a single tertiary centre provides external validation of the twin trial results in a practical day-to-day setting. It also provides insights as to how planned vaginal birth can be developed and maintained, with a key focus on safety and maternal participation in decision making. It does focus on consent and providing accurate data. What are the implications of these findings for clinical practice and/or further research? There are good grounds to encourage vaginal birth for low-risk twin pregnancies. The trend of rising caesarean rates in low-risk twin pregnancies worldwide will erode important skills for the conduct of vaginal births without any clear benefit for mothers or babies. The current situation demands careful thought about implementing innovative training opportunities for younger obstetricians. Finally, we need intelligent responses to many non-evidence-based factors which can drive clinical practice.

Twin vaginal delivery: innovate or abdicate

Neonatal safety data along with national guidelines have prompted renewed interest in vaginal delivery of twins, particularly in the case of the noncephalic second twin. Yet, the rising rate of twin cesarean deliveries, coupled with the national decline in operative obstetrics, raises concerns about the availability of providers who are skilled in twin vaginal birth. Providers are key stakeholders for increasing rates of twin vaginal delivery. We surveyed a group of practicing obstetricians to explore potential barriers to the vaginal birth of twins with a focus on delivery of the noncephalic second twin. Among 107 responding providers, only 57% would deliver a noncephalic second twin by breech extraction. Providers who preferred breech extraction had a higher rate of maternal-fetal medicine subspecialty training (26.2% vs 4.3%; P<.01) and were more likely to be in an academic practice environment (36.1% vs 10.9%; P<.01) and to practice in high-volume centers that deliver >30 sets of twins annually (57.4% vs 34.8%; P=.02). Most providers (54.2%) were familiar with the findings from the recent randomized trial that demonstrated the safety of twin vaginal birth. However, knowledge of the trial was not associated statistically with a preference for breech extraction (62.3% vs 43.5%; P=.05). Providers who preferred breech extraction were more likely to agree with recent society guidelines that encourage the vaginal birth of twins (86.9% vs 63.0%; P<.01). In an adjusted analysis, the 46% of providers with a perceived need for more training were far less likely to prefer breech extraction for delivery of a noncephalic second twin (adjusted odds ratio, 0.38; 95% confidence interval, 0.16-0.95). Furthermore, 57% of providers who would not offer their patient breech extraction would be willing to consult a colleague for support with a noncephalic twin delivery. These results suggest that scientific evidence and society opinion are likely insufficient to reverse the national trends that favor cesarean delivery for twins. Instead, implementation of provider training and support programs is critical for increasing the rates of twin vaginal birth. Changing our national landscape of vaginal twin delivery may require innovation. Without novel provider-focused strategies, we may relinquish passively the requisite skills for not only our patients but also for future generations of obstetricians.