Prospective risk of fetal death in singleton, twin, and triplet gestations: implications for practice

The Contribution of Multiple Pregnancies in Stillbirths in Greece: A Time-Trend Analysis

Introduction Multiple pregnancy is an established risk factor for fetal death. This study aimed to examine the impact of multifetal pregnancies on stillbirth rates (SBRs) in the Greek population. Methods Data on live births and stillbirths by multiplicity were derived from the Hellenic Statistical Authority, covering a 65-year period from 1957 to 2021. The SBR for multiple and single gestations, and the population attributable risk (%) (PAR (%)) stillbirth attributable to multifetal gestations were calculated, and temporal trends were assessed using joinpoint regression analysis, with annual percentage changes (APC) and 95% confidence interval (95% CI). Results In the period 1957-2021, multiple pregnancies accounted for 9.4% of total stillbirths in Greece and the overall relative risk of fetal death among multifetal gestations was 3.34, in comparison with singletons. The SBR in multiple births remained unchanged from 1957 to 1976 and showed downward trends from 1976 to 2021 (APC = -3.0, 95% CI: -3.4 to -2.7, p < 0.001). PAR (%), after two decades of stability, showed an increasing trend over the period 1975-2011 (APC = 3.4, 95% CI: 2.8 to 4.0, p < 0.001), which was reversed in the more recent decade 2011-2021 (APC = -6.1, 95% CI: -9.6 to -2.5, p = 0.001), with PAR (%) decreasing from a historical high of 19.3% in 2012 to 8.6% in 2021. Conclusion The high incidence of multiple births has a considerable impact on stillbirth rates in the Greek population. The recent downward trends of SBR and PAR (%) of multiple gestations are encouraging, however more measures and targeted interventions are needed to improve perinatal outcomes in multifetal gestation.

Risk factors for adverse outcomes in women with high-risk pregnancy and their neonates, Haiti

Objectives.

To determine the prevalence of maternal death, stillbirth and low birthweight in women with (pre-)eclampsia and complicated pregnancies or deliveries in Centre de Références des Urgences Obstétricales, an obstetric emergency hospital in Port-au-Prince, Haiti, and to identify the main risk factors for these adverse pregnancy outcomes.

Methods.

We conducted a retrospective cohort study of pregnant women admitted to Centre de Référence des Urgences Obstétricales between 2013 and 2018 using hospital records. Risk factors investigated were age group, type of pregnancy (singleton, multiple), type of delivery and use of antenatal care services.

Results.

A total of 31 509 women and 24 983 deliveries were included in the analysis. Among these, 204 (0.6%) maternal deaths (648 per 100 000 women giving birth), 1962 (7.9%) stillbirths and 11 008 (44.1%) low birthweight neonates were identified. Of all admissions, 10 991 (34.9%) were women with (pre-)eclampsia. Caesarean section significantly increased the risk of maternal death in the women with a complicated pregnancy and women with (pre-)eclampsia, but reduced the risk of stillbirth in such women. Not attending antenatal care was associated with a significantly higher risk of stillbirth (odds ratio (OR) 4.82; 95% confidence interval (CI) 3.55–6.55) and low birthweight (OR 1.40; 95% CI 1.05–1.86) for women with complicated pregnancies.

Conclusion.

To prevent and treat pregnancy complications as early as possible, antenatal care attendance is crucial. Improving the quality of and access to antenatal care services and providing it free to all pregnant women in Haiti is recommended.

Association of Gestational Age at Birth With Risk of Perinatal Mortality and Special Educational Need Among Twins

IMPORTANCE

Twin pregnancies account for 3% of live births but experience substantially more perinatal morbidity and mortality than singleton pregnancies. Optimizing the timing of birth is a key strategy in improving twin pregnancy outcomes. Current UK and US policies are based on observational studies of perinatal mortality and not on longer-term effects. The association of timing of birth with long-term childhood outcomes among twins is uncertain.

OBJECTIVE

To identify the optimal gestation week for birth of twin infants by calculating the week of birth associated with the lowest risk of short-term and long-term adverse outcomes (perinatal mortality and special educational need [SEN] at school).

DESIGN, SETTING, AND PARTICIPANTS

This population-based, data-linkage cohort study included 43 133 twin infants born at a gestational age of 34 weeks onward between January 1, 1980, and December 31, 2015, in Scotland. The data were analyzed from June 1, 2017, to March 1, 2019.

EXPOSURES

Gestational age (in weeks) at the time of birth.

MAIN OUTCOMES AND MEASURES

The primary outcomes were extended perinatal mortality and a record of SEN (≥1 of intellectual disabilities, dyslexia, physical or motor impairment, language or speech disorder, autistic spectrum disorder, and social, emotional, or behavioral difficulties) at school (children aged 4-18 years). To infer the consequence of the gestational age at birth, clinical outcomes of twin infants born at each week of gestation from 34 weeks onward were compared with those of twin infants remaining in utero thereafter.

RESULTS

Of the total 43 133 twin infants included in the study, 21 696 (50.3%) were females. Although maternity records were available for all infants, 9519 sex-discordant twin children were linked to their educational data, of whom 1069 (13.8%) had a record of SEN. Compared with twins remaining in utero (n = 26 172), birth at any gestational age from 34 to 37 weeks was associated with increased odds of perinatal death (ie, adjusted odds ratio [AOR], 1.99; 95% CI, 1.53-2.69 at 36 weeks [n = 8056]) and increased risk of SEN at school (AOR, 1.39; 95% CI, 1.11-1.74, for birth at 36 weeks compared with 37 weeks). In a competing risk analysis, the risks of stillbirth and neonatal death were balanced at 37 weeks (risk difference, 2.05; 95% CI, 0.8-3.3).

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that, in the absence of a medical complication, twins should not be routinely delivered before 37 completed weeks of gestation. These findings may help optimize shared decision-making around the timing of twin birth.

Changes in the perinatal outcomes of twin pregnancies delivered at a tertiary referral center in Korea during a 24-year period from 1995 to 2018

Objective

To analyze the changes in the clinical characteristics and perinatal outcomes of twin pregnancies delivered at a tertiary referral center in Korea during a 24-year period.

Methods

This was a retrospective cohort study of twin pregnancies delivered at 24–40 weeks of gestation, from 1995 to 2018. The subjects were divided into 4 groups according to the year of delivery: 1995–2000, 2001–2006, 2007–2012, and 2013–2018. The trends in the changes in the twin birth rate, maternal age, assisted reproductive technology (ART) pregnancy rate, chorionicity, obstetric complications, delivery outcomes, and neonatal outcomes over the periods were analyzed.

Results

A total of 2,133 twin pregnancies were included in the study. The twin birth rate increased from 16.7/1,000 in 1995–2000 to 42.2/1,000 in 2001–2006, 49.5/1,000 in 2007–2012, and 61.8/1,000 in 2013–2018. The maternal age and ART pregnancy and dichorionic twin rates increased, while the monochorionic twin rate decreased over the periods. The incidence of fetal congenital anomalies, cervical incompetence, gestational diabetes mellitus, preeclampsia, and placental abruption increased over the periods. The preterm birth (PTB) rate significantly decreased owing to the decreasing elective late-PTB rate; however, the early-PTB rate significantly increased.

Conclusion

This study found that twin pregnancies increased steadily over the last 24 years and that the increase was related to increased maternal age and ART pregnancy rate. The incidence of obstetric complications increased over the periods; however, the neonatal intensive care unit admission rate decreased, along with decreases in the elective late-PTB rate.

Risk of Stillbirth after Infertility Treatment in the United States: 2014-2017

To estimate the risk of stillbirth following infertility treatment in the United States (US), we analyzed data from the US Natality and Fetal Death files from 2014 to 2017. We built Cox proportional regression models to generate adjusted hazard ratios (HR) for the risk of stillbirth among women who utilized various modalities of infertility treatment within the study period. Women who used any infertility treatment and, specifically, assisted reproductive technology (ART), had an elevated risk of stillbirth (HR: 1.21, 95% CI:1.09 -1.33) compared to women who did not use ART. We concluded that in this population, the risk of stillbirth was elevated among women using infertility treatment.

Dizygotic Dichorionic Triamniotic Triplet Pregnancy Delivered at Full Term: An Out of Box Presentation of Triplet-A Case Report from Ethiopia

The incidence of triplet is raising several hundred percent due to wide availability of fertility therapies. It is associated with different perinatal and maternal complications. The average duration of gestation and birth weight for triplet are 32.5 weeks and 1735 grams (total weight of triplet set being about 5.2kg), respectively. However, it is not uncommon to find the rarest situations in obstetrics. Here we present a case of triplet set born from gravida 5 para 4 mother at full term (GA of 39 weeks and 3 days), dated from reliable last normal menstrual period (LNMP). Each triplet has weight comparable to average weight of singleton at term. Triplets A, B, and C weigh 2.8 kg, 3 kg, and 3.2 kg, respectively. The triplet set weigh 9 kg in aggregate. Surprisingly the neonates have no perinatal complication, but the mother developed postpartum hemorrhage secondary to uterine atony. All individual triplets are large for gestational age on adjusted fetal weight standard of triplet from singleton's growth curve. Such type of triplet outcome is unique in its presentation and has never been reported in scientific literature as to the knowledge of the authors. Thus, we can consider it as “an out of box presentation of triplet”. This initiates us to report the case.

Optimal Timing of Delivery Based on the Risk of Stillbirth and Infant Death Associated with Each Additional Week of Expectant Management in Multiple Pregnancies: a National Cohort Study of Koreans

BACKGROUND

The purpose of this study was to compare the fetal/infant mortality risk associated with each additional week of expectant management to that associated with immediate delivery in women with multiple gestations.

METHODS

This was a retrospective national cohort study of 94,170 multiple deliveries, 92,619 (98.4%) twin and 1,352 (1.44%) triplet pregnancies, between 32 0/7 and 42 6/7 weeks of gestation recorded in the Korean vital statistics database. We investigated the risks of stillbirth and infant death after birth in Korea according to the week of gestation in twin and triplet pregnancies.

RESULTS

The risk of stillbirth significantly increased between 34 and 35 weeks of gestation and between 37 and 38 weeks of gestation in twin pregnancies and between 34 and 37 weeks of gestation in triplet pregnancies. The risk of infant death following delivery gradually decreased as pregnancies approached full term. Week-by-week differences were statistically significant between 33 and 34 weeks, with decreasing risks of infant death at advancing gestational ages in twin pregnancies. At 37 weeks of gestation, the relative risk of mortality was significantly higher with expectant management compared with immediate delivery (relative risk, 3.00; 95% confidence interval, 1.41-6.38).

CONCLUSION

In twin pregnancies, delivery at 37 weeks of gestation can minimize the risks of stillbirth and infant death in uncomplicated cases, although individual maternal and fetal characteristics must be considered when determining the optimal timing of delivery. In multiple pregnancies, close fetal surveillance is needed after 34 weeks of gestation.

Prospective risk of stillbirth and neonatal complications in twin pregnancies: systematic review and meta-analysis

OBJECTIVE

To determine the risks of stillbirth and neonatal complications by gestational age in uncomplicated monochorionic and dichorionic twin pregnancies.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, and Cochrane databases (until December 2015).

REVIEW METHODS

Databases were searched without language restrictions for studies of women with uncomplicated twin pregnancies that reported rates of stillbirth and neonatal outcomes at various gestational ages. Pregnancies with unclear chorionicity, monoamnionicity, and twin to twin transfusion syndrome were excluded. Meta-analyses of observational studies and cohorts nested within randomised studies were undertaken. Prospective risk of stillbirth was computed for each study at a given week of gestation and compared with the risk of neonatal death among deliveries in the same week. Gestational age specific differences in risk were estimated for stillbirths and neonatal deaths in monochorionic and dichorionic twin pregnancies after 34 weeks' gestation.

RESULTS

32 studies (29 685 dichorionic, 5486 monochorionic pregnancies) were included. In dichorionic twin pregnancies beyond 34 weeks (15 studies, 17 830 pregnancies), the prospective weekly risk of stillbirths from expectant management and the risk of neonatal death from delivery were balanced at 37 weeks' gestation (risk difference 1.2/1000, 95% confidence interval -1.3 to 3.6; I(2)=0%). Delay in delivery by a week (to 38 weeks) led to an additional 8.8 perinatal deaths per 1000 pregnancies (95% confidence interval 3.6 to 14.0/1000; I(2)=0%) compared with the previous week. In monochorionic pregnancies beyond 34 weeks (13 studies, 2149 pregnancies), there was a trend towards an increase in stillbirths compared with neonatal deaths after 36 weeks, with an additional 2.5 per 1000 perinatal deaths, which was not significant (-12.4 to 17.4/1000; I(2)=0%). The rates of neonatal morbidity showed a consistent reduction with increasing gestational age in monochorionic and dichorionic pregnancies, and admission to the neonatal intensive care unit was the commonest neonatal complication. The actual risk of stillbirth near term might be higher than reported estimates because of the policy of planned delivery in twin pregnancies.

CONCLUSIONS

To minimise perinatal deaths, in uncomplicated dichorionic twin pregnancies delivery should be considered at 37 weeks' gestation; in monochorionic pregnancies delivery should be considered at 36 weeks.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42014007538.

APPEARANCE OF NEURODEVELOPMENTAL DISORDERS IN CHILDREN DELIVERED POST-TERM: A CROSS-SECTION STUDY

GOAL

To analyze the appearance of neurodevelopmental disorders in children delivered post-term and to find out whether prolonged pregnancy may be a cause of such disorders in a selected group participants.

PATIENTS AND METHODS

This study included a cohort of 34 children born post-term suffering from neurodevelopmental disorders who were treated at the Service for psycho-physiological and speaking disorders in Mostar, Bosnia and Herzegovina during an 18-year period.

RESULTS

There were 59.4% of male and 40.6% female patients (P=0.002). The most common neurodevelopmental disorder in the sample was intellectual disability (38.2%), followed by epilepsy (26.4%), delayed psychomotor development (14.7%), and cerebral palsy (11.7%) (P<0.001). The correlation between mothers' parity and post-term delivery was found (P=0.016).

CONCLUSION

Post-term delivery may be the cause of neurodevelopmental disorders. The most common disorder among them were intellectual difficulties.

Towards reducing variations in infant mortality and morbidity: a population-based approach

Background

Our aims were (1) to improve understanding of regional variation in early-life mortality rates and the UK’s poor performance in international comparisons; and (2) to identify the extent to which late and moderately preterm (LMPT) birth contributes to early childhood mortality and morbidity.

Objective

To undertake a programme of linked population-based research studies to work towards reducing variations in infant mortality and morbidity rates.

Design

Two interlinked streams: (1) a detailed analysis of national and regional data sets and (2) establishment of cohorts of LMPT babies and term-born control babies.

Setting

Cohorts were drawn from the geographically defined areas of Leicestershire and Nottinghamshire, and analyses were carried out at the University of Leicester.

Data sources

For stream 1, national data were obtained from four sources: the Office for National Statistics, NHS Numbers for Babies, Centre for Maternal and Child Enquiries and East Midlands and South Yorkshire Congenital Anomalies Register. For stream 2, prospective data were collected for 1130 LMPT babies and 1255 term-born control babies.

Main outcome measures

Detailed analysis of stillbirth and early childhood mortality rates with a particular focus on factors leading to biased or unfair comparison; review of clinical, health economic and developmental outcomes over the first 2 years of life for LMPT and term-born babies.

Results

The deprivation gap in neonatal mortality has widened over time, despite government efforts to reduce it. Stillbirth rates are twice as high in the most deprived as in the least deprived decile. Approximately 70% of all infant deaths are the result of either preterm birth or a major congenital abnormality, and these are heavily influenced by mothers’ exposure to deprivation. Births at < 24 weeks’ gestation constitute only 1% of all births, but account for 20% of infant mortality. Classification of birth status for these babies varies widely across England. Risk of LMPT birth is greatest in the most deprived groups within society. Compared with term-born peers, LMPT babies are at an increased risk of neonatal morbidity, neonatal unit admission and poorer long-term health and developmental outcomes. Cognitive and socioemotional development problems confer the greatest long-term burden, with the risk being amplified by socioeconomic factors. During the first 24 months of life each child born LMPT generates approximately £3500 of additional health and societal costs.

Conclusions

Health professionals should be cautious in reviewing unadjusted early-life mortality rates, particularly when these relate to individual trusts. When more sophisticated analysis is not possible, babies of < 24 weeks’ gestation should be excluded. Neonatal services should review the care they offer to babies born LMPT to ensure that it is appropriate to their needs. The risk of adverse outcome is low in LMPT children. However, the risk appears higher for some types of antenatal problems and when the mother is from a deprived background.

Future work

Future work could include studies to improve our understanding of how deprivation increases the risk of mortality and morbidity in early life and investigation of longer-term outcomes and interventions in at-risk LMPT infants to improve future attainment.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

Gestational age at delivery and neonatal outcome in uncomplicated twin pregnancies: what is the optimal gestational age for delivery according to chorionicity?

Objective

To investigate the neonatal outcome according to the gestational age at delivery and to determine the optimal timing for delivery in uncomplicated monochorionic and dichorionic twin pregnancies.

Methods

This is a retrospective cohort study of women with uncomplicated twin pregnancies delivered at or beyond 35 weeks of gestation from 1995 to 2013. The primary outcome was neonatal composite morbidity, which was defined as when either one or both twins have one or more of the followings: fetal death after 35 weeks gestation, admission to neonatal intensive care unit, mechanical ventilator requirement, respiratory distress syndrome and neonatal death. To determine the optimal gestational age for delivery according to chorionicity, we compared the neonatal composite morbidity rate between women who delivered and women who remained undelivered at each gestational week in both monochorionic and dichorionic twin pregnancies.

Results

A total of 697 twin pregnancies were included (171 monochorionic and 526 dichorionic twins). The neonatal composite morbidity rate significantly decreased with advancing gestational age at delivery and its nadir was observed at 38 and ≥39 weeks of gestation in monochorionic and dichorionic twins, respectively. However, the composite morbidity rate did not differ between women who delivered and women who remained undelivered ≥36 and ≥37 weeks in monochorionic and dichorionic twins, respectively.

Conclusion

Our data suggest that the optimal gestational age for delivery was at ≥36 and ≥37 weeks in uncomplicated monochorionic and dichorionic twin pregnancies, respectively.

Incidences of Feto-Fetal Transfusion Syndrome and Perinatal Outcomes in Triplet Gestations with Monochorionic Placentation

INTRODUCTION

This study aimed to determine the incidences of feto-fetal transfusion syndrome (FFTS) and perinatal outcomes in triplet gestations with monochorionic placentation.

MATERIALS AND METHODS

In this retrospective cohort study, we evaluated the incidences of FFTS and perinatal outcomes at 28 days of age in cases of triplet gestations with monochorionic placentation who visited our centers before 16 weeks of gestation and delivered over a period of 11 years.

RESULTS

In 41 triplet gestations (17 monochorionic triamniotic, 22 dichorionic triamniotic, 1 dichorionic diamniotic, and 1 monochorionic monoamniotic), the incidence of FFTS was 17.1%, and the median gestational age at FFTS diagnosis was 19 weeks. In 123 triplets, the incidences of fetal death and neonatal death at 28 days of age were 8.1 and 0.9%, respectively. None of the surviving infants had grade 3 or 4 intraventricular hemorrhage, while cystic periventricular leukomalacia occurred in 6 of 113 infants (5.3%). The incidence of poor outcomes (death or any major neurological complication at 28 days of age) was 13.8%.

DISCUSSION

Seventeen percent of triplet pregnancies with monochorionic placentation developed FFTS, and 14% had a poor outcome. Therefore, triplet gestations with monochorionic placentation should be followed carefully.

Induction of labor in twin pregnancies with oral misoprostol versus vaginal dinoprostone--is it effective and safe?

OBJECTIVE

To compare the effectiveness and safety of oral misoprostol versus vaginal dinoprostone for the induction of labor in twin pregnancies.

METHODS

All twin pregnancies ≥ 34 weeks 0 days that were induced with either misoprostol or dinoprostone in St. Hedwig Hospital between 2002 and 2013 were included in this retrospective study. Length of induction, mode of delivery, maternal and neonatal outcomes were compared between the two groups.

RESULTS

After identifying 186 twin mothers matching the inclusion criteria, 154 women were induced with misoprostol (group A) and 32 with dinoprostone (group B). There were no differences in demographic data between the groups. Rates of successful vaginal delivery (53.9% versus 56.3%) and length of induction to delivery (30.2 h versus 26.9 h) were also similar. There were slightly higher rates of postpartum hemorrhage in group B (16.6% versus 10.8%), but without reaching statistical significance. Neonatal outcomes regarding umbilical artery pH <7.20 and one minute Apgar also were without significant differences.

CONCLUSIONS

Study data indicate that oral misoprostol and vaginal dinoprostone are similarly effective and safe for the induction of labor in twin gestations. Further trials with larger series are needed to confirm these results.

[Induction of labor in twin pregnancies compared to singleton pregnancies; risk factors for failure]

OBJECTIVES

The aim of this study was to evaluate the modalities of induction of labour in twin pregnancies compared with singleton pregnancies and to identify risk factors for failure.

MATERIALS ET METHODS

A retrospective population-based study was conducted at the Toulouse University Hospital to compare a cohort of diamniotic twin gestations (Twin A in vertex presentation), with induction of labour ≥36 weeks of gestation, between January 2007 and December 2012, to a singleton's cohort that were induced ≥36 weeks of gestation during the 2007 year. One singleton pregnancy was matched for each twin pregnancy with parity and gestational age.

RESULTS

One hundred and fifty-six twins pregnancies met the inclusion criteria for an induction of labor and were compared to 156 single pregnancies. The same and standard protocol of induction of labor was used for the two cohorts (intrauterine balloon catheter±dinoprostone/ocytocine). The cesarean section rate for failed labor induction (cesarean in latent phase) was similar in the 2 populations (14.7% for twin vs 13.5% for single; P=0.66). The factors associated to failed induction of labor in the total population were nulliparity (OR=1.49) and Bishop score<6 at the beginning of the induction (OR=2.83).

CONCLUSION

Twin did not appear as risk of failed induction. The protocol for induction of labor in singletons may be safely proposed to twin gestations.

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.

Unconscious dynamics in twin pregnancy emerging from the Lüscher color test

OBJECTIVE

To investigate unconscious dynamics in women pregnant with twins, using Lüscher's color test to objectively measure subjective color preferences, and compare them with women with singleton pregnancies.

METHODS

The color test was administered to 50 Italian women with twin pregnancies and 100 women with singleton pregnancies.

RESULTS

Both the twin and singleton pregnancy groups said that violet was their favorite color (50 versus 49%) and brown was their least favorite color (52 versus 44%), indicating that they idealized being pregnant, but also found it physically stressful. The twin pregnancy group chose yellow as their second favorite (28 versus 17%) and were most likely to combine it with their first choice of violet (44 versus 19%, p=0.0006), indicating that they were worried about their relationships with their new babies and wanted to give birth soon. In addition, both groups preferred form 6, the sine curve on a dark background, but rejected the associated brown color 6, revealing that the women felt the need to look after themselves.

CONCLUSIONS

Both groups idealized being pregnant, but also found it physically stressful. However, the twin pregnancy group was afraid of building relationships with their babies and wanted to give birth soon.

Optimal risk assessment of small-for-gestational-age fetuses using 31-34-week biometry in a low-risk population

OBJECTIVE

To compare the performance of traditional growth charts for estimated fetal weight (EFW) and a validated pragmatic probabilistic approach using biometry at 31-34 weeks' gestation to screen for late pregnancy small-for-gestational age (SGA) fetuses in a low-risk population.

METHODS

Records of ultrasound biometry at 31-34 weeks were reviewed in 7755 consecutive low-risk women between 2002 and 2011. Fetal malformations, Doppler anomalies and preterm delivery before 37 weeks were excluded. SGA was defined by various percentile cut-offs of birth weight. The probability of SGA was modeled as a function of Z-scores of femur length, abdominal circumference and head circumference. The model was validated on a second independent dataset of 1725 pregnancies from a different screening unit. The screening performance of this probabilistic approach was compared with those of traditional EFW growth charts. The additional value of factoring in maternal characteristics was also ascertained.

RESULTS

Using national birth-weight charts, the proportions of newborns at 37-42 weeks with birth weight<3(rd) , <5(th) and<10(th) centiles were 3%, 6% and 12%, respectively, and there was a 2% rate of birth weight<2500 g. For a 10% false-positive rate, a direct probabilistic approach yielded a 51% detection rate of neonates with birth weight<10(th) centile, compared to the 32% and 48% detection rates given by the 10(th) centile cut-off of two reference charts for EFW. Adding maternal characteristics significantly improved detection rate by 2% to 53%.

CONCLUSIONS

The suggested validated approach to screening for late SGA fetuses outperforms traditional approaches using growth charts. By adding maternal characteristics, this screening method offers a favorable alternative to customized charts.

Does multiple gestation impact birthweight deficit from smoking?

OBJECTIVE

To test the hypothesis that the combined birthweight deficit from smoking in twin gestation is significantly greater than previously described for singletons.

STUDY DESIGN

Retrospective cohort study of White/Black live-born twins, 32 to 40 weeks of gestation, 1990 to 2005, Kansas City, MO. Data were analyzed by t-test, χ(2), linear and linear regression analyses.

RESULT

The cohort comprised 1190 twin pairs, 58% Whites and 55% ≥37 weeks. Smoking rate was 14.5% and similar by race (14.2% White vs 14.8%, P=0.772). The aggregate birthweight of twins of nonsmokers was greater, 5116 g ± 25 g vs 4870 g ± 59 g, P<0.001 (mean±s.d.) and the difference was 264 g (95% confidence interval, 156 to 372 g) after adjusting for other variables in linear regression analyses.

CONCLUSION

Smoking-associated growth restriction in twins is quantitatively similar to that of singletons. This finding is suggestive of dissipation or a ceiling effect to the growth-restricting effect of cigarette smoking.

Stillbirth reduction efforts and impact on early births

A major justification for the intentional delivery of a pregnancy before 39 weeks' gestation is a reduction in stillbirth. However, there is a considerable downside to late preterm or early term deliveries. Infants born before 39 weeks' gestation are at increased risk for numerous complications and even death. Thus, it is critical to identify which medical problems and circumstances place the fetus at high enough risk for stillbirth so as to justify late preterm or early term birth. This article highlights information pertinent to the pros and cons of iatrogenic preterm birth in pregnancies at risk for stillbirth.

Perinatal death of triplet pregnancies by chorionicity

OBJECTIVE

The purpose of this study was to evaluate the perinatal risk of death by chorionicity at >22 weeks of gestation of triplet pregnancies.

STUDY DESIGN

In a retrospective cohort study, the perinatal data were collected from triplet pregnancies in Japanese perinatal care centers between 1999 and 2009. We included maternal characteristics and examined the following factors: prenatal interventions, pregnancy outcome, and neonatal outcome. The association between fetal or neonatal death of triplets and chorionicity was evaluated by logistic regression analysis.

RESULTS

After the exclusion of 253 cases, the study group comprised 701 cases: 507 trichorionic triamniotic (TT) triplet pregnancies, 144 diamniotic triamniotic (DT) triplet pregnancies, and 50 monochorionic triamniotic (MT) triplet pregnancies. The mortality rate (fetal death at >22 weeks of gestation; neonatal death) in triplets was 2.6% and included 2.1% of TT triplet pregnancies, 3.2% of DT triplet pregnancies, and 5.3% of MT triplet pregnancies. No significant risk of death was identified in DT triplet pregnancies; however, MT triplet pregnancies had a 2.6-fold greater risk (adjusted odds ratio, 2.60; 95% confidence interval, 1.17-5.76; P = .019) compared with TT triplet pregnancies. Prophylactic cervical cerclage did not reduce the perinatal mortality rate at >22 weeks of gestation in triplets.

CONCLUSION

The risk of death for MT triplet pregnancies is significantly higher than that of TT triplet pregnancies; however, the risk of death for DT triplet pregnancies is not.

Developmental scores at 1 year with increasing gestational age, 37-41 weeks

OBJECTIVE

To examine the relationship between gestational age and mental and psychomotor development scores in healthy infants born between 37 and 41 weeks.

METHODS

The cohort included 1562 participants enrolled during infancy in an iron deficiency anemia preventive trial in Santiago, Chile. All participants were healthy, full-term (37-41 weeks) infants who weighed 3 kg or more at birth. Development at 12 months was assessed using the Bayley Scales of Infant Development. Using generalized linear modeling, we analyzed the association between gestational age and 1-year-old developmental status, taking into account potential confounders including birth weight percentile, gender, socioeconomic status, the home environment, iron status, and iron supplementation.

RESULTS

For each additional week of gestation, the Mental Development Index increased by 0.8 points (95% confidence interval = 0.2-1.4), and the Psychomotor Development Index increased by 1.4 points (95% confidence interval = 0.6-2.1) controlling for birth weight percentile, gender, socioeconomic status, and home environment.

CONCLUSIONS

In a large sample of healthy full-term infants, developmental scores obtained using the Bayley Scales of Infant Development at 12 months increased with gestational age (37-41 weeks). There is increasing evidence that birth at 39 to 41 weeks provides developmental advantages compared with birth at 37 to 38 weeks. Because cesarean deliveries and early-term inductions have increased to 40% of all births, consideration of ongoing brain development during the full-term period is an important medical and policy issue.

Gestational age at delivery and perinatal outcomes of twin gestations

OBJECTIVE

The optimal gestational duration for twin gestations is unknown. Epidemiologic studies show that the lowest perinatal mortality rate for twins is at 37-38 weeks, but these studies lack information on pregnancy complications and neonatal morbidities. This study evaluates pregnancy characteristics and perinatal outcomes of twins in order to assess the optimal gestational age for delivery.

STUDY DESIGN

This is a retrospective study of twins delivered at ≥36 weeks at our institution from 1991-2009. The composite rate of perinatal morbidity and mortality (including perinatal death, respiratory distress, suspected sepsis, and need for neonatal intensive care) was determined for weekly intervals from 36-39(+) weeks.

RESULTS

There were 377 twin gestations included. Of those 83% were dichorionic. Fifty-three percent had spontaneous labor and 48% were delivered by cesarean section. Perinatal outcomes improved as gestational age advanced to 38 weeks.

CONCLUSION

Perinatal morbidity and mortality rates suggest that the optimal time for delivery of twins is at 38 weeks or greater.

Delivery of twins

The aim of this article is to review current information regarding the management of twin gestations and discuss optimal pregnancy length and considerations regarding route of delivery. Limited data are available on the timing and mode of delivery for twins. For apparently uncomplicated twin pregnancies, current recommendations suggest the optimal length of gestation is 38 weeks for dichorionic diamniotic twins, 34-36 weeks for monochorionic diamniotic twins, and 32-34 weeks for monoamniotic twins. In general, vaginal trial of labor may be considered for cephalic-cephalic twins and in cases of cephalic-noncephalic twins where the provider's skills and experience allow. Cesarean is recommended in twin gestations with monoamnionicity, noncephalic presenting fetus, and those at high risk for combined vaginal-abdominal delivery. The optimal management of twin deliveries is controversial, with timing and mode of delivery dependent on multiple factors, including chorionicity, amnionicity, provider experience, and fetal presentation.

Impact of multiple births on late and moderate prematurity

Multiple gestations have an increased risk of pregnancy complications compared with singletons. Delay in childbearing and assisted reproductive techniques have remained common reasons for the increase in multiple gestations over the last few decades. Higher rates of both spontaneous and indicated preterm birth in twins and triplets lead to a significant proportion of the moderate preterm birth and late preterm birth rates. The article is a review of the causes of preterm birth and morbidities associated with these pregnancies.

Prospective risk of fetal death in uncomplicated monochorionic twins

A retrospective cohort study was carried out in a university teaching hospital to determine the prospective risk of unexpected fetal death in uncomplicated monochorionic diamniotic (MCDA) twin pregnancies after viability. All MCDA twins delivered at or after 24 weeks' gestation from July 1999 to July 2007 were included. Pregnancies with twin-twin transfusion syndrome, growth restriction, structural abnormalities, or twin reversed arterial perfusion sequence were excluded. Of the 144 MCDA twin pregnancies included in our analysis, the risk of intrauterine death was 4.9%. The prospective risk of unexpected intrauterine death was 1 in 43 after 32 weeks' gestation and 1 in 37 after 34 weeks' gestation. Our results demonstrate that despite close surveillance, the unexpected intrauterine death rate in uncomplicated MCDA twin pregnancies is high. This rate seems to increase after 34 weeks' gestation, suggesting that a policy of elective preterm delivery warrants evaluation.

Multiple gestations: timing of indicated late preterm and early-term births in uncomplicated dichorionic, monochorionic, and monoamniotic twins

In this work we review the indications for late preterm and early-term birth in uncomplicated dichorionic, monochorionic, and monoamniotic twin gestations. Uncomplicated dichorionic twins have optimal outcomes when delivered at 38 weeks' gestation. Monochorionic twins, however, are at greater risk for unexpected stillbirth, and a management plan of late preterm delivery (34-37 weeks) after informed consent is reasonable. Monoamniotic twins are at even greater risk for sudden intrauterine fetal demise, and it is recommended that these expectant mothers be managed by inpatient hospitalization with fetal testing 1-3 times per day and delivery between 32 and 34 weeks' gestation. Recommendations are also provided for the circumstance of single intrauterine fetal demise in a twin gestation.

Timing delivery of the growth-restricted fetus

Intrauterine growth restriction (IUGR) is commonly defined as an estimated fetal weight of less than the 10th percentile. While 70% of these are small for normal reasons and not at risk, 30% are pathologically small at risk for numerous complications including fetal death. In the late preterm IUGR fetus (>34 weeks), prematurity risks less and the risk of fetal demise becomes the primary concern. Pulsed-wave Doppler interrogation of the umbilical and middle cerebral artery is useful in reducing perinatal mortality, however, Doppler changes in these vessels of the IUGR fetus may not occur after 34 weeks gestation. There are no randomized trials addressing the timing of delivery of the IUGR fetus in the late preterm or early-term period. However, retrospective reports show an increase risk of fetal demise. While timing the delivery of the late preterm/early-term IUGR fetus requires consideration of multiple factors (e.g. degree of growth restriction, etiology, amniotic fluid volume, and biophysical and Doppler testing), available data suggests that delivery should occur by 37 to 38 weeks for singleton IUGR fetuses. In twin pregnancies with a co-twin IUGR fetus, chorionicity also impacts timing of delivery, but delivery should occur by 34-36 weeks.

Stillbirth and neonatal mortality in monochorionic and dichorionic twins: a population-based study

BACKGROUND

Chorionicity is one of the main predictors of higher perinatal mortality in twins. The aim of this large population-based study was to analyse stillbirth and neonatal mortality by cause of death and chorionicity and to quantify the risk of stillbirth by gestational age in dichorionic (DC) and monochorionic (MC) twins.

METHODS

We used data on twin maternities delivered in the North of England from 1998 to 2007 and notified to the Northern Survey of Twin and Multiple Pregnancy. Prospective risk of stillbirth by gestational age at death was calculated using number of stillborn fetuses at or beyond a given gestational period per 1000 fetuses in ongoing pregnancies.

RESULTS

There were 4565 twin maternities (9130 twins) with an overall twinning rate of 14.9 per 1000 maternities. The overall stillbirth and neonatal mortality rates in twins during 1998-2007 were 18.0/1000 births and 23.0/1000 live births, respectively. Stillbirth and neonatal mortality rates were significantly higher in MC than DC twins: 44.4 versus 12.2 per 1000 births [relative risk (RR): 3.6; 95% CI: 2.6-5.1], and 32.4 versus 21.4 per 1000 live births (RR: 1.5; 95% CI: 1.04-2.2), respectively. There was no significant improvement over time in either stillbirth or neonatal mortality rates in either group. The prospective risk of antepartum stillbirth was higher for MC than DC twins at all preterm gestations and the highest risk was before 28 weeks' gestation.

CONCLUSIONS

MC twins have higher rates of stillbirth and neonatal mortality than DC twins, and rates did not improve over 1998-2007. The prospective risk of antepartum stillbirth is much higher for MC twins at all gestational ages.

Uncomplicated monochorionic diamniotic twin pregnancy

There have been significant advances in our understanding of the aetiology and management of disorders specific to Monochorionic Diamniotic (MCDA) twin pregnancies like Twin-Twin Transfusion Syndrome (TTTS) and Twin Reversed Arterial Perfusion (TRAP) but there is paucity of data about the management of uncomplicated MCDA twins pregnancies. It is accepted that even in the absence of specific complications, these pregnancies are associated with increased perinatal morbidity & mortality. The aim of this review is to gather evidence regarding the management of seemingly uncomplicated monochorionic diamniotic pregnancies.

Fetal growth restriction

Normal fetal growth is determined by the genetically predetermined growth potential and further modulated by maternal, fetal, placental, and external factors. Fetal growth restriction (FGR) is a failure to reach this potential and is clinically suspected if sonographic estimates of fetal weight, size, or symmetry are abnormal. Integration of fetal anatomy assessment, amniotic fluid dynamics, uterine, umbilical, and fetal middle cerebral artery Doppler is the most effective approach to differentiate potentially manageable placenta-based FGR from aneuploidy, nonaneuploid syndromes, and viral infection. Although placental dysfunction results in a multisystem fetal syndrome with impacts on short- and long-term outcome, only cardiovascular and behavioral responses are helpful to guide surveillance and intervention. Early-onset FGR before 34 weeks gestation is readily recognized but challenging to manage as questions about optimal delivery timing remain unanswered. In contrast, near-term FGR provides less of a management challenge but is often missed as clinical findings are more subtle. Once placenta-based FGR is diagnosed, integrating multivessel Doppler and biophysical profile score provides information on longitudinal progression of placental dysfunction and degree of fetal acidemia, respectively. Choosing appropriate monitoring intervals based on anticipated disease acceleration and intervention when fetal risks exceed neonatal risks are the prevailing current management approaches.

Antenatal fetal assessment: multifetal gestation--an overview

As prevalence of multifetal gestation has increased in the United States, antenatal surveillance of these pregnancies has gained importance. This article focuses on the assessment of twin pregnancy, since critical data are lacking for the surveillance of higher order multiple gestations. Twin pregnancies encounter risks that differ in nature, frequency, and intensity from those seen in singleton pregnancies. Most of these risks stem from subnormal or discordant fetal growth or abnormalities of placentation. Sonographic modalities play key roles in antepartum surveillance. These include fetal biometry, serial growth studies, amniotic fluid volume assessment, Doppler velocimetry of fetal-placental circulation, and biophysical profile testing. Fetal heart rate testing, specifically nonstress testing, has also been used extensively in twin surveillance. This article examines the specific application of these modalities to twin gestation and reviews the best evidence available for their support. Assessment of unique risk conditions of twin-twin transfusion, monoamniotic twinning, and intrauterine death of one twin is addressed. Based on current data, a strategic outline for assessment of twin pregnancy is presented.

Integrated testing and management in fetal growth restriction

Growth-restricted fetuses are at higher risk for poor perinatal and long-term outcome than those who are appropriately grown. Multiple antenatal testing modalities can help document the sequence of fetal deterioration. The full extent of this compromise is best identified by a combination of fetal biometry, biophysical profile scoring, and arterial and venous Doppler. In the preterm growth-restricted fetus, timing of delivery is critically determined by the balance of fetal versus neonatal risks. In the near-term fetus, accurate diagnosis continues to be a challenge as unrecognized growth restriction contributes to a significant proportion of unexplained stillbirths. In this review, we present an integrated diagnostic and surveillance approach that accounts for these factors.

The influence of obstetric practices on late prematurity

In this article, the authors review the standard management of several maternal and fetal complications of pregnancy and examine the effect these practices may have on the late preterm birth rate. Given the increasing rate of late preterm birth and the increased recognition of the morbidity and mortality associated with delivery between 34 and 37 weeks, standard obstetric practices and practice patterns leading to late preterm birth should be critically evaluated. The possibility of expectant management of some pregnancy complications in the late preterm period should be investigated. Furthermore, prospective research is warranted to investigate the role of antenatal corticosteroids beyond 34 weeks.

The ultrasound estimation of amniotic fluid volume in diamniotic twin pregnancies and prediction of peripartum outcomes

OBJECTIVE

To determine ultrasonic estimations of amniotic fluid in diamniotic twins across gestation using the single deepest pocket (SDP) technique and correlate volumes to intrapartum and neonatal outcomes.

STUDY DESIGN

Prospective observational study using diamniotic dichorionic and diamniotic monochorionic pregnancies. Intrapartum and neonatal outcomes were evaluated.

RESULTS

Between April 2004 and April 2006, 299 women were recruited. There was no significant relationship between SDP and gestational age. Statistically significant differences by SDP groups (for low, normal, and high volumes) include preterm delivery (P = .043; 56, 62, and 86%), abnormal labor tracing (P = .013; 5, 8, and 27%), fetal labor intolerance (P = .026; 6, 9, and 27%), Apgar scores at 5 minutes (P = .028; 17, 10, and 27%) and any neonatal complications (P = .002; 28, 21, and 55%).

CONCLUSION

The SDP is constant between 17 and 37 weeks. Fetal labor intolerance and adverse neonatal outcomes are greater in a twin with hydramnios.

Theory of obstetrics: an epidemiologic framework for justifying medically indicated early delivery

BACKGROUND

Modern obstetrics is faced with a serious paradox. Obstetric practice is becoming increasingly interventionist based on empirical evidence but without a theoretical basis for such intervention. Whereas obstetric models of perinatal death show that mortality declines exponentially with increasing gestational duration, temporal increases in medically indicated labour induction and cesarean delivery have resulted in rising rates of preterm birth and declining rates of postterm birth. Other problems include a disconnection between patterns of gestational age-specific growth restriction (constant across gestation) and gestational age-specific perinatal mortality (exponential decline with increasing duration) and the paradox of intersecting perinatal mortality curves (low birth weight infants of smokers have lower neonatal mortality rates than the low birth weight infants of non-smokers).

DISCUSSION

The fetuses at risk approach is a causal model that brings coherence to the various perinatal phenomena. Under this formulation, pregnancy complications (such as preeclampsia), labour induction/cesarean delivery, birth, revealed small-for-gestational age and death show coherent patterns of incidence. The fetuses at risk formulation also provides a theoretical justification for medically indicated early delivery, the cornerstone of modern obstetrics. It permits a conceptualization of the number needed to treat (e.g., as low as 2 for emergency cesarean delivery in preventing perinatal death given placental abruption and fetal bradycardia) and a calculation of the marginal number needed to treat (i.e., the number of additional medically indicated labour inductions/cesarean deliveries required to prevent one perinatal death). Data from the United States showed that between 1995-96 and 1999-2000 rates of labour induction/cesarean delivery increased by 45.1 per 1,000 and perinatal mortality decreased by 0.31 per 1,000 total births among singleton pregnancies at > or = 28 weeks of gestation. The marginal number needed to treat was 145 (45.1/0.31), showing that 145 excess labour inductions/cesarean deliveries in 1999-2000 (relative to 1995-96) were responsible for preventing 1 perinatal death among singleton pregnancies at > or = 28 weeks gestation.

SUMMARY

The fetuses at risk approach, with its focus on incidence measures, provides a coherent view of perinatal phenomena. It also provides a theoretical justification for medically indicated early delivery and reconciles the contemporary divide between obstetric theory and obstetric practice.

Perinatal loss among twins

OBJECTIVE

We evaluated prenatal factors related to perinatal loss in twins, using medical records and death certificates, to determine the main perinatal event that contributed to babies' deaths.

DESIGN

This was a retrospective cohort study of 550 monochorionic diamniotic or diamniotic dichorionic twins who were delivered at Kaiser Permanente Colorado between 1994 and 2001.

MAIN OUTCOME

The main outcome of the study was perinatal loss (stillbirth or neonatal death).

OUTCOMES MEASURES

Select maternal risk factors (maternal age, race, marital status, assisted conception, past history of preterm birth, cigarette smoking, and placentation) were included in the univariable and multivariable logistic regression analysis. Data on these risk factors came from review of records from our multiple-birth perinatal database. A comprehensive review of clinical events recorded in the medical records and on the death certificate was conducted to assess the main event that contributed to the loss.

RESULTS

In the cohort of 1100 babies, there were 12 stillbirths and 34 neonatal deaths, with an overall frequency of perinatal loss of 4.2%. We found a strong association between a monochorionic diamniotic placentation and perinatal loss (adjusted odds ratio, 3.9; 95% confidence interval, 2, 7.7). At delivery, placental pathology and spontaneous preterm birth accounted for 36% and 41%, respectively, of the clinical events contributing to the demises. Compared with the medical record, review of death certificate information did not contribute significantly to the understanding of the sequence of perinatal events leading to the demise.

CONCLUSIONS

We conclude that loss in twins is most strongly associated with monochorionic diamniotic placentation. Although this condition is not preventable, early identification (by ultrasound) and referral to subspecialists may decrease the chances of perinatal loss. Prevention of spontaneous preterm birth in all women remains an important initiative in obstetric care to reduce perinatal mortality and neonatal morbidity. We believe that improvements in the reporting on death certificates will allow future research on large data sets and may provide further insight into perinatal loss in twins. We emphasize the importance of a comprehensive clinical review of each case of perinatal loss to fully understand the sequence of clinical events leading to this adverse pregnancy outcome.

Late preterm gestation: physiology of labor and implications for delivery

The late preterm infant represents a significant portion of preterm deliveries. Historically, this cohort has been referred to as near-term, which may not address adequately the increased perinatal morbidity these neonates experience. The changing demographics of pregnant women also are increasing the number of inductions in this gestational age group. More women with chronic hypertension, diabetes, and other chronic medical problems are getting pregnant, and often these pregnancies may require induction during this gestational age. The increasing numbers of multi-fetal gestations also have an average gestational age at delivery in this range of 34 to 36.6 weeks. Preeclampsia is another factor that can lead to delivery and induction during this gestational age. This article discusses some of the physiologic causes behind late preterm deliveries.

The impact of multiple gestations on late preterm (near-term) births

Multiple pregnancies currently account for 3% of all births in the United States but are disproportionately responsible for larger rates of prematurity and significant neonatal morbidity. The mean birth age for most multi-fetal pregnancies occurs during the late preterm period when both spontaneous preterm labor and iatrogenic premature birth because of obstetrical or maternal complications are common. Multiples pose numerous unique challenges, emphasizing the significant impact of plurality on late preterm births.

Étude des 178 morts fœtales in utero dans le sud de l’île de la Réunion en 2001-2004

INTRODUCTION

The perinatal mortality rate is 18.5 in the southern part of the Reunion Island (Indian Ocean), of which 2/3 are due to antepartum fetal deaths (APFD).

METHODS

During a 4-year period (2001-2004) all APFD from 22 weeks gestation were recorded and analyzed with placental histology, bacteriological samples and autopsies in 27% of cases. The Australasian and New-Zealand classification PSANZ-PDC (2000) was used. Risk factors of fetal death with monofetal pregnancies are determined in comparison with live births.

RESULTS

Out of 21.495 total births, 178 APFD were recorded. The main obstetrical risk factors were primiparity (OR 1.6, p = 0.002), maternal age over 34 years (OR 1.6, p = 0.01), hypertensive disorders of pregnancy (OR 3.0, p < .001) and multiple births (OR 2.5, p < 0.001). The great majority of APFD (76%) involved preterm fetuses, of which 61% of very preterm (<33 weeks), and 25% of fetuses were growth retarded (OR 3.9, p < 0.001). Only 8% of cases were considered unexplained. The main etiologies were infectious causes in 26% of cases, vascular fetal growth restriction (18%), specific perinatal conditions (14%) of which one-third were due to cord anomalies, preeclampsia (10%), maternal conditions (8%), congenital anomalies (8%) and ante-partum hemorrhage (7%). We discuss the interests and the limitations of using the Australian and New-Zealand classification PSANZ 2000. Intra-uterine growth retardation is one of the principal risk factors of fetal death.

CONCLUSION

Besides well-known obstetrical risk factors such as diabetes, hypertension, multiple pregnancies, all screening of intra-uterine growth retardation in the second trimester of pregnancy should include a special survey in order to minimize the incidence of APFDs.

Factors influencing adverse perinatal outcomes in pregnancies achieved through use of in vitro fertilization

OBJECTIVE

To determine the associations of specific components of IVF treatment with abnormal perinatal outcomes.

DESIGN

Case-control study.

SETTING

University-based and community-based infertility centers.

PATIENT(S)

All viable pregnancies achieved through IVF procedures performed between January 1999 and March 2004.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Infertility etiology, gonadotropin exposure, embryo manipulation, and quality.

RESULT(S)

Of 455 viable pregnancies identified during the study period, 435 met inclusion criteria. While adjusting for maternal age, race, parity, body mass index, infertility center, and year of IVF procedure, multiple gestations were associated with a 12-fold increased risk of poor perinatal outcome compared to singletons. Ovarian hyperstimulation syndrome significantly increased the risk more than 3-fold (odds ratio = 3.14; 95% confidence interval, 1.08-9.14), while endometrial thickness was found to have a significant protective effect (odds ratio = 0.89; 95% confidence interval, 0.80-0.99). We found no effect of etiology of infertility, dose or type of medication used for stimulation, use of embryo-manipulation techniques, or quality on perinatal outcome.

CONCLUSION(S)

These data confirm and quantify the risk of perinatal morbidity associated with multiple births. After adjusting for multiple births, ovarian hyperstimulation syndrome and suboptimal endometrial development are associated with adverse outcomes in pregnancies achieved through IVF. Our findings suggest that it may be the endometrium rather than the embryo that influences fetal growth and perinatal outcomes after IVF.

Neonatal mortality and morbidity rates in term twins with advancing gestational age

OBJECTIVE

The purpose of this study was to identify the gestational age with the lowest morbidity and mortality rates for twin pregnancies that reach term.

STUDY DESIGN

A retrospective cohort study carried out with 60,443 twin pairs from the United States (1995-1997). Analysis was restricted to pregnancies that had reached at least 37 weeks of gestation; groups were created on the basis of the gestational ages of 37, 38, 39, and > or = 40 weeks. The incidence of death and morbidity were calculated; multiple logistic regression models were used to estimate the independent effect of gestational age for twin A and B.

RESULTS

The neonatal mortality rate increased significantly after 40 weeks of gestation (twin A: odds ratio, 3.47 [95% CI, 2.29, 5.38]; twin B, odds ratio, 2.52 [95% CI, 1.75, 3.67]). There was also an increased risk of neonatal morbidity in the > or = 40 weeks of gestation group for twin A and B (Apgar score, < or = 3; odds ratio, 1.88 [95% CI, 1.18, 3.02], 1.74 [95% CI, 1.21, 2.52], respectively). There was a decreased risk of assisted ventilation in the 38 and 39 weeks of gestation group for twin A (odds ratio, 0.86 [95% CI, 0.77, 0.97], odds ratio, 0.83 [95% CI, 0.72, 0.95], respectively) and a decreased risk in the 39 and > or = 40 weeks of gestation groups for twin B (assisted ventilation: odds ratio, 0.83 [95% CI, 0.73, 0.93], odds ratio, 0.81 [95% CI, 0.72, 0.92], respectively).

CONCLUSION

This study suggests that the optimal date of delivery for twins should be <40 weeks of gestation; there was no compelling evidence for delivering at <38 weeks of gestation.

Progesterone for the prevention of preterm birth among women at increased risk: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study was undertaken to determine whether progestational agents, initiated in the second trimester of pregnancy, reduce the risk of delivery less than 37 weeks, among women at increased risk of spontaneous preterm birth.

STUDY DESIGN

Medline, pre-Medline, EMBASE, and Cochrane Central Register of Controlled Trials were searched. Randomized controlled trials with less than 20% lost to follow-up were included.

RESULTS

Three trials were eligible for inclusion. There was a significant reduction in risk of delivery less than 37 weeks with progestational agents (relative risk [95% CI] = 0.57 [0.36-0.90]). There was no significant effect on perinatal mortality or serious neonatal morbidity.

CONCLUSION

Progestational agents, initiated in the second trimester of pregnancy, may reduce the risk of delivery less than 37 weeks' gestation, among women at increased risk of spontaneous preterm birth, but the effect on neonatal outcome is uncertain. Larger randomized controlled trials are required to determine whether this treatment reduces perinatal mortality or serious neonatal morbidity.