Neonatal outcome of very preterm twins: policy of planned vaginal or cesarean delivery

Cesarean delivery is associated with lower neonatal mortality among breech pregnancies: a systematic review and meta-analysis of preterm deliveries ≤32 weeks of gestation

OBJECTIVE

To investigate the association between actual and planned modes of delivery, neonatal mortality, and short-term outcomes among preterm pregnancies ≤32 weeks of gestation.

DATA SOURCES

A systematic literature search was conducted in 3 main databases (PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to November 16, 2022. The protocol was registered in advance in the International Prospective Register of Systematic Reviews (CRD42022377870).

STUDY ELIGIBILITY CRITERIA

Eligible studies examined pregnancies ≤32nd gestational week. All infants received active care, and the outcomes were reported separately by different modes of delivery. Singleton and twin pregnancies at vertex and breech presentations were included. Studies that included pregnancies complicated with preeclampsia and abruptio placentae were excluded. Primary outcomes were neonatal mortality and intraventricular hemorrhage.

STUDY APPRAISAL AND SYNTHESIS METHODS

Articles were selected by title, abstract, and full text, and disagreements were resolved by consensus. Random effects model-based odds ratios with corresponding 95% confidence intervals were calculated for dichotomous outcomes. Risk Of Bias In Non-randomized Studies - of Interventions-I was used to assess the risk of bias.

RESULTS

A total of 19 observational studies were included involving a total of 16,042 preterm infants in this systematic review and meta-analysis. Actual cesarean delivery improves survival (odds ratio, 0.62; 95% confidence interval, 0.42-0.9) and decreases the incidence of intraventricular hemorrhage (odds ratio, 0.70; confidence interval, 0.57-0.85) compared to vaginal delivery. Planned cesarean delivery does not improve the survival of very and extremely preterm infants compared to vaginal delivery (odds ratio, 0.87; 95% confidence interval, 0.53-1.44). Subset analysis found significantly lower odds of death for singleton breech preterm deliveries born by both planned (odds ratio, 0.56; 95% confidence interval, 0.32-0.98) and actual (odds ratio, 0.34; 95% confidence interval, 0.13-0.88) cesarean delivery.

CONCLUSION

Cesarean delivery should be the mode of delivery for preterm ≤32 weeks of gestation breech births due to the higher mortality in preterm infants born via vaginal delivery.

[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.

Mode of delivery and neonatal outcomes in preterm twins less than 32 weeks of gestation or birthweight under 1500 g: a systematic review and meta-analyses

BACKGROUND

The mode of delivery for twins born before 32 weeks of gestation remains controversial. Our purpose is to conduct a meta-analysis of twin pregnancies less than 32 weeks or twin weight less than 1500 g, so as to find a suitable delivery mode.

METHODS

We searched PubMed database, Cochrane Library database, and EMBASE database through December 2022. This protocol was registered with PROSPERO (CRD42023386946) prior to initiation. Studies that compared vaginal delivery to cesarean section for newborns less than 32 weeks of gestation or birthweight under 1500 g were included. The primary result was neonatal mortality rate. Secondary result was neonatal morbidity. The quality of literatures included in the research was evaluated in accordance with Newcastle-Ottawa Scale (NOS) literature quality evaluation scale. We use odds ratio (OR) as the effect index for binary variables. Point estimates and 95% confidence intervals (95% CI) were calculated. P < 0. 05 indicated statistically significant difference.

RESULTS

Our search generated 5310 articles, and a total of 8 articles comprising a total of 14,703 newborns were included in the analysis. The odds ratios of neonatal mortality rate were for twins delivered by vaginal delivery compared to cesarean section were 0.84 (95% CI 0.57-1.24, P = 0.38). The 5-min Apgar score < 7 (95% CI 0.44-1.75, P = 0.72), necrotizing enterocolitis (95% CI 0.81-1.19, P = 0.82), intraventricular hemorrhage (95% CI 0.41-1.86, P = 0.71), periventricular leukomalacia (95% CI 0.16-4.52, P = 0.84), bronchopulmonary dysplasia (95% CI 0.88-1.36, P = 0.42), and respiratory distress syndrome (95% CI 0.23-2.01, P = 0.48) were not statistically significant between the two groups.

CONCLUSION

We have observed that vaginal delivery does not confer an increased risk of neonatal morbidity and mortality in twins born before 32 weeks of gestation. However, the current results are affected by substantial heterogeneity and confounding factors. We still need high-quality randomized-controlled studies require to address this important question.

Does structured obstetric management play a role in the delivery mode and neonatal outcome of twin pregnancies?

PURPOSE

While the optimal delivery method of twin pregnancies is debated, the rate of cesarean deliveries is increasing. This retrospective study evaluates delivery methods and neonatal outcome of twin pregnancies during two time periods and aims to identify predictive factors for the delivery outcome.

METHODS

553 twin pregnancies were identified in the institutional database of the University Women's Hospital Freiburg, Germany. 230 and 323 deliveries occurred in period I (2009-2014) and period II (2015-2021), respectively. Cesarean births due to non-vertex position of the first fetus were excluded. In period II, the management of twin pregnancies was reviewed; adjusted and systematic training with standardized procedures was implemented.

RESULTS

Period II showed significantly lower rates of planned cesarean deliveries (44.0% vs. 63.5%, p < 0.0001) and higher rates of vaginal deliveries (68% vs. 52.4%, p = 0.02). Independent risk factors for primary cesarean delivery were period I, maternal age > 40 years, nulliparity, a history with a previous cesarean, gestational age < 37 completed weeks, monochorionicity and increasing birth weight difference (per 100 g or > 20%). Predictive factors for successful vaginal delivery were previous vaginal delivery gestational age between 34 and 36 weeks and vertex/vertex presentation of the fetuses. The neonatal outcomes of period I and II were not significantly different, but planned cesareans in general were associated with increased admission rates to the neonatal intensive care units. Inter-twin interval had no significant impact on neonatal outcome.

CONCLUSION

Structured regular training of obstetrical procedures may significantly reduce high cesarean rates and increase the benefit-risk ratio of vaginal deliveries.

Steroid Metabolome Analysis in Dichorionic Diamniotic Twin Pregnancy

Steroid hormones have diverse roles in pregnancy; some help stabilise pregnancy and influence the stability of pregnancy and the onset of labour. Changes and disorders in steroidogenesis may be involved in several pregnancy pathologies. To date, only a few studies have performed a very limited steroid analysis in multiple pregnancies. Our teams investigated multiple pregnancies regarding the biosynthesis, transport, and effects of steroids. We recruited two groups of patients: pregnant women with multiple pregnancies as the study group, and a control singleton pregnancies group. Blood samples were drawn from the participants and analysed. Information about the mother, foetus, delivery, and newborn was extracted from medical records. The data were then analysed. The gestational age of twin pregnancies during delivery ranged from 35 + 3 to 39 + 3 weeks, while it was 38 + 1 to 41 + 1 weeks for the controls. Our findings provide answers to questions regarding the steroidome in multiple pregnancies. Results demonstrate differences in the steroidome between singleton and twin pregnancies. These were based on the presence of two placentae and two foetal adrenal glands, both with separate enzymatic activity. Since every newborn was delivered by caesarean section, analysis was not negatively influenced by changes in the steroid metabolome associated with the spontaneous onset of labour.

Fetal Outcomes in Preterm Cesarean Sections

Introduction

Neonatal mortality is a major challenge in low-middle-income countries. The current study was conducted to assess the association between preterm cesarean delivery and fetal outcomes.

Methods

A prospective study was conducted at the Combined Military Hospital in Peshawar, Pakistan, from October 1, 2020, to March 31, 2021. All women reporting to the hospital with a cephalic presentation and singleton pregnancies between the 27th and 34th weeks of gestation were included in the study. Pregnancies with an abnormal presentation, those diagnosed with a congenital abnormality, and those with indications for growth restriction or preterm delivery were excluded from the study. We also excluded infants delivered via vacuum or forceps. The outcomes of interest in this study included neonatal death prior to discharge, neonatal respiratory distress, sepsis, intraventricular hemorrhage (IVH), seizure, subdural hemorrhage (SDH), or appearance, pulse, grimace, activity, and respiration (APGAR) test score of less than 7 at five minutes. Maternal features including diabetes, hypertension and gestational age of delivery, parity, previous cesarean sections (CS), and last pregnancy outcomes were documented in a predefined pro forma.

Results

Our sample size consisted of 288 women, who were classified into two groups. Group A comprised 144 women who gave birth vaginally and group B consisted of 144 women who underwent CS. It was observed that women who underwent cesareans had a higher likelihood of a history of hypertension and related pathologies. It was also observed that these women had a greater likelihood of being of higher age compared to women who underwent vaginal deliveries. Neonates of women who had CS were at a greater risk of presenting with respiratory distress than those who had spontaneous vaginal deliveries.

Conclusion

Based on our findings, respiratory distress was significantly more common in babies of women who delivered via CS. However, there was no difference in neonatal outcomes in terms of IVH, seizures, SDH, and APGAR score of <7.

Guideline No. 428: Management of Dichorionic Twin Pregnancies

OBJECTIVE

To review evidence-based recommendations for the management of dichorionic twin pregnancies.

TARGET POPULATION

Pregnant women with a dichorionic twin pregnancy.

BENEFITS, HARMS, AND COSTS

Implementation of the recommendations in this guideline may improve the management of twin pregnancies and reduce neonatal and maternal morbidity and mortality.

EVIDENCE

Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate controlled vocabulary (e.g., twin, preterm birth). Results were restricted to systematic reviews, randomized controlled trials, controlled clinical trials, and observational studies. There were no date limits, but results were limited to English- or French-language materials.

VALIDATION METHODS

The content and recommendations were drafted and agreed upon by the principal authors. The Board of the SOGC approved the final draft for publication. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED AUDIENCE

Obstetricians, family physicians, nurses, midwives, maternal-fetal medicine specialists, radiologists, and other health care providers who care for women with twin pregnancies.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Favipiravir exposure and pregnancy outcome of COVID-19 patients

Objective

COVID-19 is a rapidly spreading disease and many people have been infected in a short time. Favipiravir is under investigation for the treatment of COVID-19 and given to patients in many countries following emergency use approval. Based on data from animal studies, favipiravir use is contraindicated during pregnancy. Currently, there is no human data except for a single case report on use of favipiravir in pregnancy.

Study design

This article includes the outcomes of 29 pregnancies reported to the Clinical Pharmacology and Toxicology Unit regarding favipiravir use in pregnancy. For drug risk assessment, maternal characteristics were obtained at first contact. After the expected day of delivery, follow-up is conducted by phone call and all relevant data regarding pregnancy and newborn outcome were documented.

Results

Of the 29 pregnancies exposed to favipiravir, 5 were electively terminated and 24 resulted in live birth. There were no miscarriages or no stillbirths. There were 25 live births including one pair of twins. Three children were born premature, and one infant had patent foramen ovale. Birth weights, lengths and head circumferences of all infants were within normal range.

Conclusion

The results of the study indicate that favipiravir is unlikely to be a major human teratogen, but experience is still limited for a well-grounded risk assessment. Although these findings may be useful for the physicians and patients, larger studies are needed due to small number of cases.

Risk Factors for Periventricular Leukomalacia in Preterm Infants: A Systematic Review, Meta-analysis, and GRADE-Based Assessment of Certainty of Evidence

BACKGROUND

We analyzed the certainty of evidence (CoE) for risk factors of periventricular leukomalacia (PVL) in preterm neonates, a common morbidity of prematurity.

METHODS

Medline, CENTRAL, Embase, and CINAHL were searched. Cohort and case-control studies and randomised randomized controlled trials were included. Data extraction was performed in duplicate. A random random-effects meta-analysis was utilizedused. CoE was evaluated as per Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines.

RESULTS

One hundred eighty-six studies evaluating 95 risk factors for PVL were included. Of the 2,509,507 neonates assessed, 16,569 were diagnosed with PVL. Intraventricular hemorrhage [adjusted odds ratio: 3.22 (2.52-4.12)] had moderate CoE for its association with PVL. Other factors such as hypocarbia, chorioamnionitis, PPROM >48 hour, multifetal pregnancy reduction, antenatal indomethacin, lack of antenatal steroids, perinatal asphyxia, ventilation, shock/hypotension, patent ductus arteriosus requiring surgical ligation, late-onset circulatory collapse, sepsis, necrotizing enterocolitis, and neonatal surgery showed significant association with PVL after adjustment for confounders (CoE: very low to low). Amongst the risk factors associated with mother placental fetal (MPF) triad, there was paucity of literature related to genetic predisposition and defective placentation. Sensitivity analysis revealed that the strength of association between invasive ventilation and PVL decreased over time (P < 0.01), suggesting progress in ventilation strategies. Limited studies had evaluated diffuse PVL.

CONCLUSION

Despite decades of research, our findings indicate that the CoE is low to very low for most of the commonly attributed risk factors of PVL. Future studies should evaluate genetic predisposition and defective placentation in the MPF triad contributing to PVL. Studies evaluating exclusively diffuse PVL are warranted.

Mode of delivery in multiple pregnancies

The mode of delivery in multiple pregnancies has been subject to vigorous debates during the last few decades. Although observational and retrospective data were accumulated, it was not until the publication of the Twin Birth Study that evidence-based recommendations could emerge. However, although some of the most pressing questions were answered by the Twin Birth Study, other questions were left outside the scope of the study. The questions were of great interest and included the following topics: the impact of gestational age, the influence of chorionicity, and the generalizability of the results for women with a previous uterine scar. The current evidence supported a trial of labor in dichorionic-diamniotic or monochorionic-diamniotic twin pregnancies in which the first twin is in cephalic presentation at ≥32 weeks' gestation. Dichorionic-diamniotic, monochorionic-diamniotic, and monochorionic-monoamniotic twins should be delivered at 37 0/7 to 38 0/7, 36 0/7 to 37 0/7, and 32 0/7 to 34 0/7 weeks' gestation, respectively. Breech extraction done by a competent healthcare provider seemed to offer a higher chance of successful vaginal delivery of the second twin than the external cephalic version. The current data did not allow for a clear recommendation regarding the mode of delivery in very preterm birth of low birthweight twins, but most studies did not demonstrate a clear benefit of cesarean delivery vs trial of labor. Furthermore, a trial of labor seemed safe in women with a previous cesarean delivery. Cesarean delivery is likely beneficial for twin pregnancies with the first twin in breech presentation, monochorionic-monoamniotic twins, and higher-order multiple pregnancies. In all multiple pregnancies, delivery should be performed by an experienced practitioner competent in multiple pregnancy deliveries.

Screening, Management and Delivery in Twin Pregnancy

The following AWMF guideline (DGGG/AGG & DEGUM responsible) deals with the diagnosis, screening and management of twins as well as the timing and mode of birth.Twin pregnancies can be classified as dichorionic diamniotic (DC DA), monochorionic diamniotic (MC DA) and monochorionic monoamniotic (MC MA) which are always monochorionic.Twin pregnancies can be concordant (both twins are affected) or discordant (only one twin is affected) for chromosomal defects, malformations, growth restriction and hemodynamic disorders.Chorionicity is the prognostically most significant parameter. Monochorial twins have significantly higher risks of intrauterine morbidity and mortality compared to dichorial twins.In particular, general aspects of twin pregnancies such as dating, determination of chorionicity and amnionicity, the labeling of twin fetuses and the perinatal switch phenomenon are discussed.Routine monitoring of MC and DC twin pregnancies with ultrasound at 11-13^+ 6 weeks of gestation for chromosomal defects, invasive prenatal diagnosis, first-trimester NT or CRL discrepancies, early diagnosis of fetal anatomical defects, and management of twins with abnormalities, including selective fetocide, is described.Second trimester screening and management for preterm birth, intrauterine selective growth restriction (sFGR), classification of monochorial twins with sFGR, and management of the surviving twin after the death of the co-twin are described.Complications exclusively affecting MC twins include Twin to Twin Transfusion Syndrome (TTTS) with the important topics screening, prognosis, complications of laser therapy, timing of delivery, risks for brain abnormalities and delayed neurological development, Twin Anemia-Polycythemia Sequence (TAPS) and Twin Reversed Arterial Perfusion (TRAP) Sequence. This also includes MC MA twins as well as conjoined twins.Finally, the birth mode and time for DC and MC twin pregnancies are described.The information is summarized in 62 recommendations for action, 4 tables and 8 illustrations with comprehensive background texts.The guideline is an international guideline adaptation (ISUOG, NICE) as well as a systematic literature search and is up-to-date.

Evaluation of the risk of umbilical cord prolapse in the second twin during vaginal delivery: a retrospective cohort study

OBJECTIVE

This study aimed to evaluate the success rate of vaginal delivery, the reasons for unplanned caesarean delivery, the rate of umbilical cord prolapse and the risk of umbilical cord prolapse in twin deliveries.

DESIGN

Retrospective cohort study.

SETTING

Single institution.

PARTICIPANTS

This study included 455 women pregnant with twins (307 dichorionic and 148 monochorionic) who attempted vaginal delivery from January 2009 to August 2018. The following criteria were considered for vaginal delivery: diamniotic twins, cephalic presentation of the first twin, no history of uterine scar, no other indications for caesarean delivery, no major structural abnormality in either twin and no fetal aneuploidy.

RESULTS

The rate of vaginal delivery of both twins was 89.5% (407 of 455), caesarean delivery of both twins was 7.7% (35 of 455) and caesarean delivery of only the second twin was 2.9% (13 of 455). The major reasons for unplanned caesarean delivery were arrest of labour and non-reassuring fetal heart rate pattern. The rate of umbilical cord prolapse in the second twin was 1.8% (8 of 455). Multivariate analysis revealed that abnormal umbilical cord insertion in the second twin (velamentous or marginal) was the only significant factor for umbilical cord prolapse in the second twin (OR, 5.05, 95% CI 1.139 to 22.472, p=0.033).

CONCLUSIONS

Abnormal umbilical cord insertion in the second twin (velamentous or marginal) was a significant factor for umbilical cord prolapse during delivery. Antenatal assessment of the second twin's umbilical cord insertion using ultrasonography would be beneficial.

Planned Mode of Delivery of Preterm Twins and Neonatal and 2-Year Outcomes

OBJECTIVE

To assess neonatal and 2-year outcomes for preterm twins born after planned vaginal delivery compared with planned cesarean delivery.

METHODS

Women with preterm cephalic first twins delivered after preterm labor or preterm prelabor rupture of membranes from 24 0/7 to 34 6/7 weeks of gestation, with both fetuses alive at the beginning of labor, were identified from the national prospective population-based Etude Epidémiologique sur les Petits Ages Gestationnels 2 cohort study. Planned vaginal delivery was defined as vaginal delivery or cesarean delivery performed during labor. Planned cesarean delivery was considered if performed during labor for the indication of preterm twins or before labor whatever the indication. A propensity score analysis was used to compare planned vaginal delivery and planned cesarean delivery. Outcomes analyzed separately for the first and second twins were survival at discharge, survival at discharge without severe morbidity, and survival at 2 years of corrected age without neurosensory impairment.

RESULTS

Among the 932 women with a twin pregnancy, 549 were excluded mainly as a result of the first twin in noncephalic presentation, cause of delivery other than preterm labor or preterm prelabor rupture of membranes, at least one twin died before labor, and gestational age at delivery less than 24 weeks of gestation. The planned vaginal delivery group included 276 women and the planned cesarean delivery group 107. For first and second twins, survival at discharge (97.7% vs 98.3% and 95.6% vs 97.1%, respectively), survival at discharge without severe morbidity (91.6% vs 88.8% and 90.3% vs 84.5%, respectively), and survival at 2 years of corrected age without neurosensory impairment (96.0% vs 95.4% and 92.9% vs 90.8%, respectively) did not differ significantly between the planned vaginal delivery and planned cesarean delivery groups. Propensity score analysis showed that planned cesarean delivery was not associated with improved outcomes with the caveat that the infrequency of death and disability limited the statistical power of the study to detect potentially clinically meaningful differences between planned modes of delivery.

CONCLUSION

Planned cesarean delivery for women in preterm labor or with preterm prelabor rupture of membranes was not associated with improved neonatal outcomes or 2-year outcomes.

The impact of mode of delivery on the outcome in very preterm twins

Objective: Studies on the optimal mode of delivery in women with a twin pregnancy <32 weeks are scarce. We studied the effects of the mode of delivery on perinatal and maternal outcomes in very preterm twin pregnancy.Study Design: Population-based cohort study including all women with twin pregnancy who delivered very preterm (26-32 weeks of gestation) in the Netherlands between January 2000 and December 2010. We compared perinatal mortality and neonatal and maternal morbidity according to the intended mode of delivery as well as to the actual mode of delivery. Perinatal outcomes were paired taking into account the dependency between the children of the same twin pregnancy and were also analysed for each child separately. We used logistic regression to correct for possible confounding factors.Results: We studied 1,655 women with a very preterm delivery of a twin pregnancy. A planned caesarean section (n = 212) was associated with a significantly higher perinatal mortality compared to a planned vaginal delivery (n = 1.443) (10% compared to 6.5%; adjusted odds ratio (OR) 2.5, 95% confidence interval (CI) 1.5-4.2). The same applied for perinatal morbidity (66% compared to 63%; adjusted OR 1.5, 95% CI 1.1-2.0), maternal morbidity (17% compared to 4.9%; adjusted OR 4.0, 95% CI 2.6-6.3) and for perinatal mortality for the second twin (7.1% compared to 3.5% adjusted OR 2.9, 95% CI 1.7-5.2).Conclusion: In very preterm delivery of twins a vaginal delivery is the preferred mode of delivery.

In which groups of pregnant women can the caesarean delivery rate likely be reduced safely in the USA? A multicentre cross-sectional study

OBJECTIVES

To identify obstetrical subgroups in which (1) the caesarean delivery (CD) rate may be reduced without compromising safety and (2) CD may be associated with better perinatal outcomes.

DESIGN

A multicentre cross-sectional study.

SETTING

19 hospitals in the USA that participated in the Consortium on Safe Labor.

PARTICIPANTS

228 562 pregnant women in 2002-2008.

MAIN OUTCOME MEASURES

Maternal and neonatal safety was measured using the individual Weighted Adverse Outcome Score.

METHODS

Women were divided into 10 subgroups according to a modified Robson classification system. Generalised estimated equation model was used to examine the relationships between mode of delivery and Weighted Adverse Outcome Score in each subgroup.

RESULTS

The overall caesarean rate was 31.2%. Repeat CD contributed 29.5% of all CD, followed by nulliparas with labour induction (15.3%) and non-cephalic presentation (14.3%). The caesarean rates in induced nulliparas with a term singleton cephalic pregnancy and women with previous CD were 31.6% and 82.0%, respectively. CD had no clinically meaningful association with perinatal outcomes in most subgroups. However, in singleton preterm breech presentation and preterm twin gestation with the first twin in non-cephalic presentation, CD was associated with substantially improved maternal and perinatal outcomes.

CONCLUSIONS

Women with repeat CD, term non-cephalic presentation, term twins or other multiple gestation and preterm births may be the potential targets for safely reducing prelabour CD rate, while nulliparas or multiparas with spontaneous or induced labour, women with repeat CD, term non-cephalic presentation, term twins or other multiple gestation and preterm births are potential targets for reducing intrapartum CD rate without compromising maternal and neonatal safety in the USA. On the other hand, CD may still be associated with better perinatal outcomes in women with singleton preterm breech presentation or preterm twins with the first twin in non-cephalic presentation.

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.

What is the safest mode of delivery for extremely preterm cephalic/non-cephalic twin pairs? A systematic review and meta-analyses

Background

Given the controversy around mode of delivery, our objective was to assess the evidence regarding the safest mode of delivery for actively resuscitated extremely preterm cephalic/non-cephalic twin pairs before 28 weeks of gestation.

Methods

We searched Cochrane CENTRAL, MEDLINE, EMBASE and http://clinicaltrials.gov from January 1994 to January 2017. Two reviewers independently screened titles, abstracts and full text articles, extracted data and assessed risk of bias. We included randomized controlled trials and observational studies. Our primary outcome was a composite of neonatal death (<28 days of life) and severe brain injury in survivors (intraventricular hemorrhage grade ≥ 3 or periventricular leukomalacia). We performed random-effects meta-analyses, generating odds ratios with 95% confidence intervals for the first and second twin separately, and for both twins together. We assessed the risk of bias using a modified Newcastle Ottawa Scale (NOS) for observational studies and used Grading of Recommendations Assessment, Development and Evaluation approach (GRADE).

Results

Our search generated 2695 articles, and after duplicate removal, we screened 2051 titles and abstracts, selecting 113 articles for full-text review. We contacted 36 authors, and ultimately, three observational studies met our inclusion criteria. In cephalic/non-cephalic twin pairs delivered by caesarean section compared to vaginal birth at 24⁺⁰–27⁺⁶ weeks the odds ratio for our composite outcome of neonatal death and severe brain injury for the cephalic first twin was 0.35 (95% CI 0.00–92.61, two studies, I² = 76%), 1.69 for the non-cephalic second twin (95% CI 0.04–72.81, two studies, I² = 55%) and 0.83 for both twins (95% CI 0.05–13.43, two studies, I² = 56%). According to the modified Newcastle Ottawa Scale we assessed individual study quality as being at high risk of bias and according to GRADE the overall evidence for our primary outcomes was very low.

Conclusion

Our systematic review on the safest mode of delivery for extremely preterm cephalic/non-cephalic twin pairs found very limited existing evidence, without significant differences in neonatal death and severe brain injury by mode of delivery.

Electronic supplementary material

The online version of this article (10.1186/s12884-017-1554-7) contains supplementary material, which is available to authorized users.

Respiratory morbidity in twins by birth order, gestational age and mode of delivery

OBJECTIVE

To evaluate the relationship between respiratory morbidity in twins by gestational age, birth order and mode of delivery.

METHODS

All twin deliveries at <37 weeks, registered in a national database, in the period 2003-2012 were classified into four gestational age groups: 33-36, 30-32, 28-29, and <28 weeks. Outcome variables included transient tachypnea of the newborn (TTN), respiratory distress syndrome (RDS) and need for assisted ventilation.

RESULTS

A total of 1836 twins were born vaginally, and 2142 twins were born by cesarean delivery, for a grand total of 3978 twins. TTN did not appear to be related to birth order and to the mode of delivery. In contrast, RDS was more frequent among the second born twins in the vaginal birth groups born at 30-36 weeks [odds ratio (OR) 2.5, 95% confidence interval (CI) 1.2-5.1 and OR 2.0, 95% CI 1.2-3.5 for 33-36 weeks and 30-32 weeks, respectively], whereas this trend was seen in the cesarean birth groups born earlier (OR 3.8, 95% CI 1.1-13.0 for 28-29 weeks). Cesarean delivery significantly increased the frequency of RDS in twin A as well as in twin B compared with vaginal birth, but only at gestational ages <30 weeks.

CONCLUSION

Mode of delivery and birth order have a gestational age dependent effect on the incidence of RDS.

Preterm birth in twin pregnancies: Clinical outcomes and predictive parameters

Objective:

To document the neonatal outcomes of preterm birth in twin pregnancies and to investigate whether perinatal and obstetric parameters are associated with clinical outcomes.

Methods:

This retrospective trial was conducted on data gathered from 176 preterm twins delivered in the obstetrics and gynecology department of our tertiary care center. Data extracted from medical files of 88 pregnant women who gave preterm birth (at 26^0/7 to 36^6/7 gestational weeks) to twins were analyzed. Maternal/fetal descriptive and obstetric parameters, sonographic data, route of delivery, indication for cesarean section, birth weight, Apgar scores, head circumference, umbilical cord length and placental weight were noted.

Results:

The average age of the pregnant women was 28.8±6.4 years and ultrasonographic gestational age was 31.9±2.6 weeks. Apgar scores at 1^st minute were affected significantly by fetal body weight (p=0.001), gestational age (p=0.001), height (p=0.004) and head circumference (p=0.011). None of these variables exhibited a noteworthy effect on Apgar scores at 5^th minute.

Conclusion:

Efforts must be made to achieve advancement of gestational age until delivery in the follow-up preterm of twins. A well-established algorithm with special emphasis to risk factors is necessary to standardize and popularize the appropriate management strategy.