Trends in twin pregnancies and mode of delivery during the last 30 years: inconsistency between guidelines and clinical practice

The Strong Correlation Between Multiple Births and Preterm Birth Rates in Greece From 1991 to 2022

Background This study aims to investigate the correlation between the rising preterm birth rate (PBR) in Greece from 1991 to 2022 and the incidence of multiple births. Methodology Official data on live births in Greece from 1991 to 2022 were sourced from the Hellenic Statistical Authority. The PBR, defined as the number of live births occurring at <37 gestational weeks, and the multiple birth rate (MBR), representing live births from multifetal gestations, were calculated per 100 total live births. The relationship between the PBR and the MBR was evaluated using the non-parametric Spearman's rank correlation coefficient (rho). This association was confirmed through linear regression models, with MBR as the independent variable and PBR as the dependent variable, calculating the beta coefficient (β) and the coefficient of determination (R-squared). Results A very strong direct positive correlation was identified between PBR and MBR throughout the study period, with a Spearman's rho of 0.950 (p < 0.001). This conclusion was further supported by the linear regression model, which yielded a β coefficient of 3.32 (95% confidence interval = 2.78 to 3.86, p < 0.001). The R-squared was 0.838, indicating that the change in MBR explained 83.8% of the rise in PBR. The strongest correlations were observed for moderate PBR (32-33 weeks) with a rho of 0.962 (p < 0.001) and late PBR (34-36 weeks) with a rho of 0.940 (p < 0.001). During the period of a steep increase in prematurity rates in the country (1991-2011), an almost perfect correlation between PBR and MBR (rho = 0.987, p < 0.001) was noted. However, in recent years (2011-2022), characterized by a marginal increase in PBR, this association diminished, with a rho of 0.655 (p = 0.021). Conclusions This analysis revealed a strong positive correlation between the PBR and MBR in Greece from 1991 to 2022, underscoring the significant impact of multiple pregnancies on the substantial increase in preterm births within the Greek population.

Mild neonatal morbidity in twins by planned mode of delivery: a secondary analysis of the Twin Birth Study

BACKGROUND

The Twin Birth Study showed no differences in major severe adverse neonatal outcomes between those with planned vaginal delivery and those with planned cesarean delivery.

OBJECTIVE

This was a secondary analysis of the Twin Birth Study in which mild neonatal morbidities, not previously reported, were compared between parturients with planned cesarean deliveries and those with planned vaginal delivery in twin births.

STUDY DESIGN

This was a secondary analysis of the Twin Birth Study. In this study, women with a twin pregnancy at 32+0/7 to 38+6/7 weeks of gestation with the first twin in cephalic presentation and with an estimated weight between 1500 and 4000 g were randomized to either planned cesarean delivery or planned vaginal delivery. The primary outcome of this study was a composite mild neonatal outcome of respiratory and neurologic morbidities and neonatal intensive care unit admission that were not reported in the original Twin Birth Study at 34+0/7 to 38+6/7 weeks of gestation. A multivariable logistic regression analysis was used to identify factors associated with the composite adverse neonatal outcomes. Neonatal outcomes were further stratified by gestational age at delivery and by actual mode of delivery.

RESULTS

A total of 1304 women and 1326 women were randomly assigned to planned cesarean delivery and planned vaginal delivery, respectively. Demographic and obstetrical characteristics were similar between the study groups. The rate of cesarean delivery was 90.1% in the planned cesarean delivery group and 40.1% in the planned vaginal delivery group. There was no significant difference in the primary composite outcome between the groups (10.6% vs 11.3%; P=.45) neither by planned mode of delivery nor by actual mode of delivery. Stratification by gestational age found a lower rate of the primary outcomes at ≥38+0/7 weeks of gestation in the planned cesarean delivery group when compared with the planned vaginal delivery group (4.8% vs 10.8%, respectively; P=.02). Furthermore, a lower risk for some individual outcomes was reported in the planned cesarean delivery group when compared with the planned vaginal delivery group, including intraventricular hemorrhage stage 1 to 2 (0.2% vs 0.6%; P<.05), low Apgar scores (0.8% vs 2.3%; P<.05), pH <7.0 (0.3 vs 1%; P<.05), and assisted ventilation needed at delivery (0.4% vs 0.9%; P<.05).

CONCLUSION

In twin deliveries, with the first twin in the cephalic presentation, composite mild neonatal morbidity was not affected by the planned mode of delivery. These findings reinforce the original results of the Twin Birth Study. Nevertheless, an increased composite outcome after 38 weeks' gestation and a higher risk for some individual morbidities in the planned vaginal delivery group might be viewed as a concerning signal for the safety of vaginal delivery in twin deliveries and requires further research.

Perinatal outcome of twin pregnancies among mothers who gave birth in Adama Hospital Medical College, Central Ethiopia

Introduction

Twin pregnancy carries a high risk of pregnancy-related complications including adverse perinatal outcomes. Although evidence from international studies indicated an increased risk of adverse perinatal outcomes in twin pregnancies, little is known about the adverse perinatal outcomes in twin pregnancies and associated factors in Ethiopia. The purpose of this study was, therefore, to estimate the incidence of twin pregnancies and related-adverse perinatal outcomes and identify factors associated with adverse perinatal outcomes in twin pregnancies in Ethiopia.

Methods

A hospital-based retrospective cross-sectional study was conducted among 322 mothers who gave twin birth at Adama Hospital Medical College between 08 July 2015 and 07 June 2017. In this study, the adverse perinatal outcome was defined as the presence of any of the following main conditions: low birth weight, preterm birth, stillbirth, low Apgar Scores, mal-presentation, Admission to neonatal Intensive Care Unit (NICU), and early neonatal deaths. The data were analyzed using SPSS version 20.0. Multivariable logistic regression was conducted to identify factors associated with adverse perinatal outcome at 95% CI or P-value of less than 0.05.

Result

Of 10,850 births recorded in the hospital, 354 births were twins and 322 of these paired records had complete perinatal information. One hundred ninety-nine (61.8%) of the 322 paired birth records had at least one adverse perinatal outcome on one or both twins. Low birth weight was the most common perinatal outcome followed by preterm birth. After adjusting for confounding factors, younger maternal age (AOR = 4.1, 95% CI; 1.3, 12.5) and not having ultrasound scan during antenatal care (AOR = 2.0, 95% CI: 1.2, 3.1) were significantly associated with adverse perinatal outcomes.

Conclusion

The incidence of adverse perinatal outcome in twin pregnancies was high, that is, in 61.8% of twin births, there was at least one adverse perinatal outcome on one or both twins. Moreover, younger maternal age at birth and not having an ultrasound scan during antenatal care were found to be strong predictors for the observed high incidence of adverse perinatal outcomes.

Pregnancy outcomes in twin pregnancies over 10 years

OBJECTIVE

The aim of this study was to evaluate the changes in twin pregnancy outcomes between 2007 and 2016 in a Korean population.

METHODS

The data for this nationwide population-based study was obtained from the national birth registry of the Korean National Statistical Office and the Health Insurance Review & Assessment Service of Korea. Women with twin pregnancies who gave birth between 2007 and 2016 were included.

RESULTS

From 2007 to 2016, the rate of twin pregnancies increased (1.37% vs. 1.91%, respectively, P<0.0001). The risk of preterm birth (adjusted odds ratio [aOR], 1.77; 95% confidence interval [CI], 1.66-1.89) also increased; however, the risk of twin growth discordance (aOR, 0.90; 95% CI, 0.82-0.99) decreased. The risks of cesarean section (aOR, 1.16; 95% CI, 1.03-1.29), gestational diabetes mellitus (aOR, 2.10; 95% CI, 1.83-2.39), and postpartum hemorrhage (aOR, 1.27; 95% CI, 1.14-1.41) all increased from 2007 to 2016.

CONCLUSION

Twin pregnancy outcomes have changed significantly in Korea over a recent 10-year period.

Twin pregnancy and risk of postpartum hemorrhage

Objective: To identify maternal and peripartum characteristics in twin gestations that are associated with postpartum hemorrhage (PPH) in which one or more units of packed red blood cells (PRBCs) were either administered or recommended but declined (PPH + PRBC).Methods: This retrospective cohort study evaluated all women with twin gestations who delivered at greater than 23 weeks of gestational age at a single, tertiary medical center from 2011 to 2016. Patients were included if they had documentation of estimated blood loss (EBL) at delivery and complete inpatient medical records available for review. Patients with incomplete records or an intrauterine fetal demise of one or both twins were excluded. The primary outcome was PPH + PRBC. Secondary outcomes included PPH with delivery EBL ≥1500 ml, PPH with atony and uterotonic administration, PPH with maternal hemorrhagic morbidity (MHM), and PPH with severe maternal morbidity (SMM). MHM was a composite outcome defined as PPH associated with any of the following: atony requiring uterotonics, any PRBC transfusion (≥1 unit), uterine or hypogastric artery ligation, hysterectomy, compression sutures, intrauterine balloon tamponade, uterine artery embolization, and/or exploratory laparotomy. SMM was a composite outcome defined as PPH associated with any of the following: administration of ≥4 units of PRBC, administration of ≥2 units of PRBC, and ≥2 units of fresh frozen plasma (FFP), return to operating room for any major procedure (excludes dilation and curettage), any peripartum hysterectomy, uterine artery embolization, intrauterine balloon tamponade or compression suture placed and administration of ≥2 units of PRBC, and/or intensive care unit (ICU) admission for invasive monitoring/treatment. A multivariable logistic regression analysis was performed.Results: A total of 1081 women with twin gestations were included. PPH + PRBC occurred in 4.4% (n = 48), delivery EBL ≥1500 ml occurred in 3.9% (n = 42), and atony with uterotonic administration occurred in 12.1% (n = 131) of the study population. The rate of MHM and SMM were 13.9% (n = 150) and 1.9% (n = 20), respectively. Although the rate of cesarean delivery was high overall (83.2%), it was nearly universal in the PPH + PRBC group (97.9%; p < .02). PPH + PRBC occurred at a rate of 0.5% (n = 1/182) among vaginally delivered twins compared to 5.2% (n = 47/899) among those delivered by cesarean (p < .03). The final multivariable logistic regression model to predict PPH + PRBC identified six significant maternal and peripartum factors: nulliparity, either pregestational or gestational diabetes, intrapartum magnesium sulfate, admission hematocrit <30%, admission platelets <100 000/µL and administration of general anesthesia.Conclusions: A number of maternal and peripartum factors are associated with PPH in twin gestations. Optimization of maternal hematologic parameters and chronic medical conditions, and reduction in the rate of cesarean delivery in twin pregnancies may decrease the risk of postpartum hemorrhage.

Breastfeeding Twins: Factors Related to Weaning

BACKGROUND

Many factors may influence a woman's decision to start and maintain breastfeeding. Research aim: This study aimed to investigate the factors associated with breastfeeding cessation in twin infants during the first 6 months after birth and to describe the main reasons for weaning cited by mothers of twins.

METHODS

This is a secondary data analysis of a prospective randomized trial conducted in Brazil. Data were obtained through longitudinal quantitative and qualitative self-reported interviews. One hundred twenty-eight women pregnant with twins and their 256 infants were followed for up to approximately 6 months, during which time breastfeeding data were obtained through face-to-face interviews at three different points after birth: 30 to 40 days (Time 1), 90 days (Time 2), and 180 days (Time 3). The association between weaning and the investigated factors was examined using survival analysis methodologies.

RESULTS

Nonexclusive breastfeeding ( p = .004, Cox proportional hazards regression model), a lack of support during the lactation period ( p = .001), difficulty breastfeeding ( p = .003), a breastfeeding duration shorter than 12 months in a previous pregnancy ( p = .001), and infants' birth weight less than 2,300 g ( p < .001) were the factors associated with breastfeeding cessation. The main reasons for weaning cited by mothers of twins were insufficient human milk supply, infants' behavior, and returning to work.

CONCLUSION

We have identified the factors associated with weaning in twin infants during the first 180 days of life. This knowledge can help improve strategies to increase breastfeeding rates in twins.

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.

Breastfeeding education and support for women with twins or higher order multiples

BACKGROUND

There are rising rates of multiple births worldwide with associated higher rates of complications and more hospital care, often due to prematurity. While there is strong evidence about the risks of not breastfeeding, rates of breastfeeding in women who have given birth to more than one infant are lower than with singleton births. Breastfeeding more than one infant can be more challenging because of difficulties associated with the birth or prematurity. The extra demands on the mother of frequent suckling, coordinating the needs of more than one infant or admission to the neonatal intensive care unit can lead to delayed initiation or early cessation. Additional options such as breast milk expression, the use of donor milk or different methods of supplementary feeding may be considered. Support and education about breastfeeding has been found to improve the duration of any breastfeeding for healthy term infants and their mothers, however evidence is lacking about interventions that are effective to support women with twins or higher order multiples.

OBJECTIVES

To assess effectiveness of breastfeeding education and support for women with twins or higher order multiples.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 June 2016), ClinicalTrials.gov (30 June 2016), the WHO International Clinical Trials Registry Platform (ICTRP) (1 July 2016), the excluded studies list from the equivalent Cochrane review of singletons, and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised or quasi-randomised trials comparing extra education or support for women with twins or higher order multiples were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. We planned to assess the quality of evidence using the GRADE approach, but were unable to analyse any data.

MAIN RESULTS

We found 10 trials (23 reports) of education and support for breastfeeding that included women with twins or higher order multiples. The quality of evidence was mixed, and the risk of bias was mostly high or unclear. It is difficult to blind women or staff to group allocation for this intervention, so in all studies there was high risk of performance and high or unclear risk of detection bias. Trials recruited 5787 women (this included 512 women interviewed as part of a cluster randomised trial); of these, data were available from two studies for 42 women with twins or higher order multiples. None of the interventions were specifically designed for women with more than one infant, and the outcomes for multiples were not reported separately for each infant. Due to the scarcity of evidence and the format in which data were reported, a narrative description of the data is presented, no analyses are presented in this review, and we were unable to GRADE the evidence.The two trials with data for women with multiple births compared home nurse visits versus usual care (15 women), and telephone peer counselling versus usual care (27 women). The number of women who initiated breastfeeding was reported (all 15 women in one study, 25 out of 27 women in one study). Stopping any breastfeeding before four to six weeks postpartum, stopping exclusive breastfeeding before four to six weeks postpartum, stopping any breastfeeding before six months postpartum andstopping exclusive breastfeeding before six months postpartum were not explicitly reported, and there were insufficient data to draw any meaningful conclusions from survival data. Stopping breast milk expression before four to six weeks postpartum, andstopping breast milk expression before six months postpartum were not reported. Measures ofmaternal satisfaction were reported in one study of 15 women, but there were insufficient data to draw any conclusions; no other secondary outcomes were reported for women with multiple births in either study. No adverse events were reported.

AUTHORS' CONCLUSIONS

We found no evidence from randomised controlled trials about the effectiveness of breastfeeding education and support for women with twins or higher order multiples, or the most effective way to provide education and support . There was no evidence about the best way to deliver the intervention, the timing of care, or the best person to deliver the care. There is a need for well-designed, adequately powered studies of interventions designed for women with twins or higher order multiples to find out what types of education and support are effective in helping these mothers to breastfeed their babies.

Mode and timing of twin delivery and perinatal outcomes in low- and middle-income countries: a secondary analysis of the WHO Multicountry Survey on Maternal and Newborn Health

OBJECTIVE

To describe the mode and timing of delivery of twin pregnancies at ≥34 weeks of gestation and their association with perinatal outcomes.

DESIGN

Secondary analysis of a cross-sectional study.

POPULATION

Twin deliveries at ≥34 weeks of gestation from 21 low- and middle-income countries participating in the WHO Multicountry Survey on Maternal and Newborn Health.

METHODS

Descriptive analysis and effect estimates using multilevel logistic regression.

MAIN OUTCOME MEASURES

Stillbirth, perinatal mortality, and neonatal near miss (use of selected life saving interventions at birth).

RESULTS

The average length of gestation at delivery was 37.6 weeks. Of all twin deliveries, 16.8 and 17.6% were delivered by caesarean section before and after the onset of labour, respectively. Prelabour caesarean delivery was associated with older maternal age, higher institutional capacity and wealth of the country. Compared with spontaneous vaginal delivery, lower risks of neonatal near miss (adjusted odds ratio, aOR, 0.63; 95% confidence interval, 95% CI, 0.44-0.94) were found among prelabour caesarean deliveries. A lower risk of early neonatal mortality (aOR 0.12; 95% CI 0.02-0.56) was also observed among prelabour caesarean deliveries with nonvertex presentation of the first twin. The week of gestation with the lowest rate of prospective fetal death varied by fetal presentation: 37 weeks for vertex-vertex; 39 weeks for vertex-nonvertex; and 38 weeks for a nonvertex first twin.

CONCLUSIONS

The prelabour caesarean delivery rate among twins varied largely between countries, probably as a result of overuse of caesarean delivery in wealthier countries and limited access to caesarean delivery in low-income countries. Prelabour delivery may be beneficial when the first twin is nonvertex. International guidelines for optimal twin delivery methods are needed.