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

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.

High-flow nasal cannula (HFNC) vs continuous positive airway pressure (CPAP) vs nasal intermittent positive pressure ventilation as primary respiratory support in infants of ≥ 32 weeks gestational age (GA): study protocol for a three-arm multi-center randomized controlled trial

BACKGROUND

Health problems in neonates with gestational age (GA) ≥ 32 weeks remain a major medical concern. Respiratory distress (RD) is one of the common reasons for admission of neonates with GA ≥ 32 weeks. Noninvasive ventilation (NIV) represents a crucial approach to treat RD, and currently, the most used NIV modes in neonatal intensive care unit include high-flow nasal cannula (HFNC), continuous positive airway pressure (CPAP), and nasal intermittent positive pressure ventilation. Although extensive evidence supports the use of NIPPV in neonates with a GA < 32 weeks, limited data exist regarding its effectiveness in neonates with GA ≥ 32 weeks. Therefore, the aim of this study is to compare the clinical efficacy of HFNC, CPAP, and NIPPV as primary NIV in neonates with GA ≥ 32 weeks who experience RD.

METHODS

This trial is designed as an assessor-blinded, three-arm, multi-center, parallel, randomized controlled trial, conducted in neonates ≥ 32 weeks' GA requiring primary NIV in the first 24 h of life. The neonates will be randomly assigned to one of three groups: HFNC, CPAP or NIPPV group. The effectiveness, safety and comfort of NIV will be evaluated. The primary outcome is the occurrence of treatment failure within 72 h after enrollment. Secondary outcomes include death before discharge, surfactant treatment within 72 h after randomization, duration of both noninvasive and invasive mechanical ventilation, duration of oxygen therapy, bronchopulmonary dysplasia, time to achieve full enteral nutrition, necrotizing enterocolitis, duration of admission, cost of admission, air leak syndrome, nasal trauma, and comfort score.

DISCUSSION

Currently, there is a paucity of data regarding the utilization of NIPPV in neonates with GA ≥ 32 weeks. This study will provide clinical evidence for the development of respiratory treatment strategies in neonates at GA ≥ 32 weeks with RD, with the aim of minimizing the incidence of tracheal intubation and reducing the complications associated with NIV.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR2300069192. Registered on March 9, 2023, https://www.chictr.org.cn/showproj.html?proj=171491 .

Birth order and morbidity and mortality to hospital discharge among inborn very low-birthweight, very preterm twin infants admitted to neonatal intensive care: a retrospective cohort study

OBJECTIVE

To know the association of birth order with the risk of morbidity and mortality in very low-birthweight (VLBW) twin infants less than 32 weeks' gestational age (GA).

DESIGN

Retrospective cohort study.

SETTING

Infants admitted to the collaborating centres of the Spanish SEN1500 neonatal network.

PATIENTS

Liveborn VLBW twin infants, with GA from 23⁺⁰ weeks to 31⁺⁶ weeks, without congenital anomalies, admitted from 2011 to 2020. Outborn patients were excluded.

MAIN OUTCOME MEASURES

Respiratory distress syndrome (RDS), patent ductus arteriosus, bronchopulmonary dysplasia (BPD), necrotising enterocolitis, major brain damage (MBD), late-onset neonatal sepsis, severe retinopathy of prematurity, survival and survival without morbidity. Crude and adjusted incidence rate ratios were calculated.

RESULTS

Among 2111 twin pairs included, the second twin had higher risk (adjusted risk ratio (aRR) of RDS (aRR 1.08, 95% CI 1.03 to 1.12) and need for surfactant (aRR1.10, 95% CI 1.05 to 1.16). No other significant differences were found, neither in survival (aRR 1.01, 95% CI 0.99 to 1.03) nor in survival without BPD (aRR 1.02, 95% CI 0.99 to 1.05), survival without MBD (aRR 1.02, 95% CI 0.99 to 1.06) nor in survival without major morbidity (aRR 0.97, 95% CI 0.92 to 1.03). However, second twins born by caesarean section (C-section) after a vaginally delivered first twin had less overall survival and survival without MBD.

CONCLUSION

In modern perinatology, second twins are still more unstable immediately after birth and require more resuscitation. After admission to the neonatal intensive care unit, they are at increased risk of RDS, but not other conditions, except for second twins delivered by C-section after a first twin delivered vaginally, who have decreased overall survival and survival without major brain injury.

Prediction of Neonatal Respiratory Morbidity Assessed by Quantitative Ultrasound Lung Texture Analysis in Twin Pregnancies

The objective of this study was to evaluate the performance of quantitative ultrasound of fetal lung texture analysis in predicting neonatal respiratory morbidity (NRM) in twin pregnancies. This was an ambispective study involving consecutive cases. Eligible cases included twin pregnancies between 27.0 and 38.6 weeks of gestation, for which an ultrasound image of the fetal thorax was obtained within 48 h of delivery. Images were analyzed using quantusFLM^® version 3.0. The primary outcome of this study was neonatal respiratory morbidity, defined as the occurrence of either transient tachypnea of the newborn or respiratory distress syndrome. The performance of quantusFLM^® in predicting NRM was analyzed by matching quantitative ultrasound analysis and clinical outcomes. This study included 166 images. Neonatal respiratory morbidity occurred in 12.7% of cases, and it was predicted by quantusFLM^® analysis with an overall sensitivity of 42.9%, specificity of 95.9%, positive predictive value of 60%, and negative predictive value of 92.1%. The accuracy was 89.2%, with a positive likelihood ratio of 10.4, and a negative likelihood ratio of 0.6. The results of this study demonstrate the good prediction capability of NRM in twin pregnancies using a non-invasive lung texture analysis software. The test showed an overall good performance with high specificity, negative predictive value, and accuracy.

Concordance of the risk of neonatal respiratory morbidity assessed by quantitative ultrasound lung texture analysis in fetuses of twin pregnancies

To evaluate the concordance of the risk of neonatal respiratory morbidity (NRM) assessed by quantitative ultrasound lung texture analysis (QuantusFLM) between twin fetuses of the same pregnancy. Prospective study conducted in twin pregnancies. Fetal ultrasound lung images were obtained at 26.0–38.6 weeks of gestation. Categorical (high or low) and continuous results of the risk of NRM were compared between twins. Fetal ultrasound lung images from 131 pairs (262 images) of twins were included. The images were classified into three gestational age ranges: Group 1 (26.0–29.6 weeks, 78 images, 39 pairs [29.8%]); Group 2 (30.0–33.6 weeks, 98 images, 49 pairs [37.4%]) and Group 3 (34.0–38.6 weeks, 86 images, 43 pairs [32.8%]). Concordance was good in Groups 1 and 3 and moderate in Group 2. In Groups 2 and 3 at least one fetus presented high-risk results in 26.5% and 11.6% of twin pairs, respectively. Only gestational age < 32 weeks, gestational diabetes mellitus, and spontaneous conception were associated with a high risk of NRM in Group 2. There was good concordance of the risk of NRM between twins < 30.0 weeks and > 34.0 weeks. From 30.0 to 33.6 weeks 26.5% of the twin pairs had discordant results, with moderate concordance of the risk of NRM.

Outcomes of ultrasound-indicated cerclage in twin pregnancies with a short cervical length

OBJECTIVE

To investigate the outcomes of ultrasound-indicated cerclage in dichorionic-diamniotic (DCDA) twin pregnancies with a short cervical length.

MATERIALS AND METHODS

This was a retrospective cohort study of DCDA twin pregnancies with a short cervical length (≤25 mm) from January 2000 to July 2017 to compare maternal and neonatal outcomes. Additional sub-analysis was performed by dividing the patients into two subgroups by a cervical length ≤15 mm and between 16 and 25 mm.

RESULTS

One hundred and eight women were initially diagnosed with twin pregnancies and cervical insufficiency. After excluding cases not meeting the study criteria, 46 women were recruited for analysis, of whom 33 underwent ultrasound-indicated cerclage. The delivery age of the cerclage group was significantly later than the non-cerclage group (34.85 ± 3.91 versus 31.08 ± 5.25 weeks, p = 0.011), and the latency was significantly longer in the cerclage group than in the non-cerclage group (86.09 ± 41.32 versus 52.31 ± 33.24 days, p = 0.014). Sub-analysis revealed that these benefits were significant in the subgroup of a cervical length ≤15 mm. Both first twin (twin A) and second twin (twin B) had a significantly decreased rate of neonatal intensive care unit admission in the cerclage group. However, twin A had more promising outcomes with significantly decreased rates of neonatal respiratory distress syndrome (6.7% versus 50.0%, p = 0.004) and sepsis (0% versus 25.0%, p = 0.019).

CONCLUSION

Ultrasound-indicated cerclage in DCDA twin pregnancies can decrease preterm birth and prolong the latency. It also decreases neonatal morbidity, and is especially beneficial for twin A.

Respiratory distress in newborn infants in Western Switzerland

AIM

To assess epidemiological data about respiratory distress (RD) in newborn infants hospitalized in Western Switzerland.

METHODS

During 1 year, two questionnaires were sent out to the seven neonatal and pediatric units of a well-defined geographic region in Switzerland. Data about their obstetrical activity and details about all newborn infants hospitalized with RD were collected, asking for pre-, peri-, and postnatal clinical data in association with RD.

RESULTS

Almost 6% of all newborn infants born in the Canton of Vaud had to be hospitalized for RD. All newborn infants below 32 weeks of gestational age (GA) had developed RD, accounting for 14.6% of all neonates, hospitalized with RD, whereas the moderate to late preterm infants contributed with 36.8% much more to the RD hospitalizations. Associated factors to hospitalizations with RD were prematurity, cesarean delivery, and multiple births.

CONCLUSIONS

Efforts should be made to reduce avoidable RD by reconsidering the management of pregnancies with premature rupture of the membranes around 34 weeks of GA and by delaying elective cesarean sections after 39 completed weeks of gestation.

Outcomes of extremely premature infants with twin-twin transfusion syndrome treated by laser therapy

OBJECTIVE

To compare short-term and long-term outcomes of preterm infants born at <29 weeks of gestational age (GA) with twin-twin transfusion syndrome (TTTS) treated with laser therapy to preterm twin infants without TTTS.

DESIGN

Retrospective case-control study comparing 33 preterm TTTS twins to 101 preterm diamniotic-dichorionic (di-di) twins born at our institution between 2006 and 2015.

RESULTS

GA at birth were 26.4 ± 1.4 weeks (TTTS) and 26.9 ± 1.6 weeks (di-di) (p = 0.07). TTTS premature newborns were less exposed to antenatal steroids (p = 0.01), more frequently born by C-section (p = 0.005), received more surfactant therapy (p = 0.004, and were smaller for GA (p < 0.001). When adjusted for antenatal steroids and birth weight, TTTS status was not associated with increased mortality (HR 1.66, 95% CI 0.77-3.56, p = 0.20). No differences were found on neurodevelopmental outcomes at 18 months of corrected GA.

CONCLUSION

Premature TTTS newborns treated with fetal laser therapy had similar survival and neurodevelopmental outcomes compared to preterm di-di twins without TTTS.

Risk of intra-amniotic infection/inflammation and respiratory distress syndrome according to the birth order in twin preterm neonates

Objective: Prior studies have suggested that nonpresenting twins are more likely to develop respiratory distress syndrome (RDS) than presenting twins. While the underlying mechanism is not known, exposure to intra-amniotic infection/inflammation (IAI) has been associated with a reduced risk of RDS in singleton gestations. In the current study, we compared the risk of RDS in preterm twin neonates according to birth order with adjustment for the presence or absence of IAI.Methods: The study population consisted of consecutive twin neonates who delivered ≤35 weeks and underwent amniocentesis within 7 days of delivery. The frequency of RDS and IAI was compared between presenting and nonpresenting twin pairs. Amniotic fluid (AF) was cultured for aerobic/anaerobic bacteria and genital mycoplasma. IAI was defined as a positive AF culture or an AF white cell count ≥19/mm³.Results: A total of 120 twin pairs were enrolled. Compared with presenting twins, nonpresenting twins had a lower risk of IAI (36 vs. 26%, respectively, p < .05), but a higher risk of RDS (18 vs. 25%, respectively, p < .05). In multivariate analysis, only IAI remained significantly associated with RDS (OR 0.18, 95% CI 0.05-0.65), whereas birth order was not.Conclusions: In preterm twin neonates, the increased risk of RDS in nonpresenting twins is likely due to lower exposure to IAI and not birth order.

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.