Monochorionic diamniotic in vitro fertilization twins have a decreased incidence of twin-to-twin transfusion syndrome

Maternal and perinatal outcomes in twin pregnancies following assisted reproduction: a systematic review and meta-analysis involving 802 462 pregnancies

BACKGROUND

ART is associated with higher rates of twin pregnancies than singleton pregnancies. Whether twin pregnancies conceived following ART have additional maternal and neonatal complications compared with non-ART twin pregnancies is not known.

OBJECTIVE AND RATIONALE

The objective was to quantify the risk of adverse maternal and perinatal outcomes among twin pregnancies conceived following ART compared with non-ART and natural conception. Existing reviews vary in the reported outcomes, with many studies including triplet pregnancies in the study population. Therefore, we aimed to perform an up-to-date review with an in-depth analysis of maternal and perinatal outcomes limited to twin pregnancies.

SEARCH METHODS

We searched electronic databases MEDLINE and EMBASE from January 1990 to May 2023 without language restrictions. All cohort studies reporting maternal and perinatal outcomes following ART compared with non-ART twin pregnancies and natural conception were included. Case-control studies, case reports, case series, animal studies, and in vitro studies were excluded. The Newcastle-Ottawa Scale was used to assess the methodological quality of the studies. Using random-effects meta-analysis, the estimates were pooled and the findings were reported as odds ratios (OR) with 95% CI.

OUTCOMES

We included 111 studies (802 462 pregnancies). Twin pregnancies conceived following ART were at higher risk of preterm birth at <34 weeks (OR 1.33, 95% CI 1.14-1.56, 29 studies, I2 = 73%), <37 weeks (OR 1.26, 95% CI 1.19-1.33, 70 studies, I2 = 76%), hypertensive disorders in pregnancy (OR 1.29, 95% CI 1.14-1.46, 59 studies, I2 = 87%), gestational diabetes mellitus (OR 1.61, 95% CI 1.48-1.75, 51 studies, I2 = 65%), and caesarean delivery (OR 1.80, 95% CI 1.65-1.97, 70 studies, I2 = 89%) compared with non-ART twins. The risks for the above maternal outcomes were also increased in the ART group compared with natural conception. Of the perinatal outcomes, ART twins were at significantly increased risk of congenital malformations (OR 1.17, 95% CI 1.05-1.30, 39 studies, I2 = 59%), birthweight discordance (>25% (OR 1.31, 95% CI 1.05-1.63, 7 studies, I2 = 0%)), respiratory distress syndrome (OR 1.32, 95% CI 1.09-1.60, 16 studies, I2 = 61%), and neonatal intensive care unit admission (OR 1.24, 95% CI 1.14-1.35, 32 studies, I2 = 87%) compared with non-ART twins. When comparing ART with natural conception, the risk of respiratory distress syndrome, intensive care admissions, and birthweight discordance >25% was higher among the ART group. Perinatal complications, such as stillbirth (OR 0.83, 95% CI 0.70-0.99, 33 studies, I2 = 49%), small for gestational age <10th centile (OR 0.90, 95% CI 0.85-0.95, 26 studies, I2 = 36%), and twin-twin transfusion syndrome (OR 0.45, 95% CI 0.25-0.82, 9 studies, I2 = 25%), were reduced in twin pregnancies conceived with ART versus those without ART. The above perinatal complications were also fewer amongst the ART group than natural conception.

WIDER IMPLICATIONS

ART twin pregnancies are associated with higher maternal complications than non-ART pregnancies and natural conception, with varied perinatal outcomes. Women seeking ART should be counselled about the increased risks of ART twin pregnancies and should be closely monitored in pregnancy for complications. We recommend exercising caution when interpreting the study findings owing to the study's limitations.

Retrospective comparison of monochorionic diamniotic twin pregnancies stratified by spontaneous or artificial conception

OBJECTIVES

To compare outcomes of monochorionic diamniotic (MCDA) twin pregnancies by in vitro fertilization (IVF) vs. spontaneously conceived counterparts.

METHODS

Retrospective comparison. Data about MCDA twin pregnancies, conceived spontaneously or by IVF, attending the Twin Pregnancy Care Unit of Sant'Anna Hospital in Turin (Italy) between January 1st 2010 and March 31st 2022, were collected retrospectively. Obstetric, fetal, and neonatal outcomes of MCDA twin pregnancies by IVF were compared to those of spontaneously conceived counterparts. Data were described by univariate and multivariate analysis.

RESULTS

541 MCDA twin pregnancies were included in the study, among which 45 conceived by IVF and 496 spontaneously conceived. Women with IVF twins were older than those who conceived spontaneously (36.7 ± 5.7 vs. 32.1 ± 5.2 years; p<0.001). No significant difference in the prevalence of pregnancy complications between the two groups was found, except for an increased incidence of hypertensive disorders among IVF pregnancies (17.8 vs. 8.5 %; p=0.039), which resulted nonsignificant after adjusting for maternal age and parity (aOR 1.9, 95 % CI 0.8-4.6). Data about 1,046 live born babies (90 conceived by IVF and 956 spontaneously) were also collected: perinatal outcomes did not differ between the two groups.

CONCLUSIONS

Our results suggest that MCDA twin pregnancies following IVF are not at increased risk of adverse outcomes compared to spontaneous MCDA twin pregnancies.

Are there differences between monochorionic twin placentas after spontaneous and assisted conception?

INTRODUCTION

No data are available on the placental characteristics of monochorionic twin pregnancies conceived by in vitro fertilization (IVF). This study investigates the differences between placentas from monochorionic diamniotic (MCDA) twin pregnancies conceived spontaneously and those conceived after IVF.

METHODS

This is a retrospective analysis of placental data from a consecutive series of MCDA twin pregnancies followed from the first trimester. The following placental characteristics were compared between IVF versus spontaneous MCDA pregnancies: placental sharing and birth weight discordance relative to placental sharing, the placental angioarchitecture (number, type, and size of anastomoses), and the umbilical cord insertion types.

RESULTS

Of the 256 MCDA placentas included in this analysis, 32 (12%) were conceived through IVF and 224 (88%) spontaneously. MCDA twin placentas after IVF did not differ significantly from MCDA twin placentas after spontaneous conception regarding placental sharing, birthweight discordance relative to sharing discordance, and angioarchitecture. There was a trend toward more discordant cord insertions (combination eccentric and velamentous) in IVF (25%) than in spontaneously conceived placentas (12%) (P = 0.05).

DISCUSSION

No differences could be demonstrated between MCDA placentation after spontaneous conception and IVF. Any differences in pregnancy outcome between spontaneous and IVF conceived MCDA twins may not be related to differences in placental sharing, angioarchitecture and cord insertion type.

Comparison of outcomes of monochorionic twin pregnancies conceived by assisted reproductive technology vs. spontaneous conceptions: A systematic review and meta-analysis

BACKGROUND

This review aimed to assess if monochorionic twin pregnancies conceived by assisted conception have worse maternal and neonatal outcomes as compared to those conceived naturally.

METHODS

Datasets of PubMed, ScienceDirect, CENTRAL, Embase, and Google Scholar were searched for studies comparing maternal and neonatal outcomes of monochorionic twin pregnancies conceived by assisted vs. spontaneous methods.

RESULTS

Eight studies comparing 337 assisted with 2,711 spontaneously conceived monochorionic twin pregnancies were included. Meta-analysis revealed that the mode of conception of monochorionic twin pregnancies had no impact on the risk of hypertensive disorders of pregnancy (HDP) (OR: 1.36 95% CI, 0.73, 2.54 I ² = 9% p = 0.03), twin-twin transfusion syndrome (TTTS) (OR: 0.83 95% CI, 0.52, 1.31 I ² = 0% p = 0.42), and very preterm delivery (OR: 1.18 95% CI, 0.74, 1.88 I ² = 41% p = 0.49). We noted no statistically significant difference in the mean birth weights (MD: -17.66 95% CI, -157.23, 121.91 I ² = 82% p = 0.80), risk of intra-uterine death (OR: 0.90 95% CI, 0.51, 1.60 I ² = 36% p = 0.73) and small for gestational age between the two groups (OR: 0.92 95% CI, 0.67, 1.26 I ² = 0% p = 0.59). There was an increased risk of caesarean sections (OR: 1.34 95% CI, 1.00, 1.80 I ² = 0% p = 0.05) and neonatal death with assisted conceptions as compared to spontaneous conceptions (OR: 2.35 95% CI, 1.11, 5.01 I ² = 37% p = 0.03).

CONCLUSION

Monochorionic twin pregnancies conceived via assisted reproductive technology have a heightened risk of cesarean section and neonatal deaths. However, there is a need for further studies to supplement current evidence.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=325133, identifier: CRD42022325133.

The mystery of monozygotic twinning II: What can monozygotic twinning tell us about Amyoplasia from a review of the various mechanisms and types of monozygotic twinning?

Monozygotic (MZ) twins ("identical twins") are essentially unique to human beings. Why and how they arise is not known. This article reviews the possible different types of MZ twinning recognized in the previous article on twins and arthrogryposis. There appear to be at least three subgroups of MZ twinning: spontaneous, familial, and those related to artificial reproductive technologies. Each is likely to have different etiologies and different secondary findings. Spontaneous MZ twinning may relate to "overripe ova." Amyoplasia, a specific nongenetic form of arthrogryposis, appears to occur in spontaneous MZ twinning and may be related to twin-twin transfusion.

Monochorionic twins after in-vitro fertilization: do they have poorer outcomes?

OBJECTIVE

To compare the outcome of monochorionic diamniotic (MCDA) twin pregnancies conceived by in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) with that of spontaneously conceived MCDA twins.

METHODS

This was a retrospective cohort study of MCDA twin pregnancies conceived after IVF/ICSI or spontaneously, followed from the first trimester onwards at a single center between January 2002 and September 2018. The primary outcome was survival per fetus from the first trimester until 28 days after birth. Secondary outcome measures were number of survivors, miscarriage, termination of pregnancy, intrauterine and neonatal death, major congenital anomalies, twin-twin transfusion syndrome, selective fetal growth restriction, gestational age at birth, delivery before 32 weeks' gestation, mode of delivery, admission to the neonatal intensive care unit, birth weight and birth-weight discordance.

RESULTS

Of the 654 MCDA pregnancies included in the analysis, 80 were conceived by IVF/ICSI and 574 spontaneously. Overall fetal and neonatal survival was significantly lower in the IVF/ICSI group than in the spontaneous-conception group (79% vs 90%; P = 0.001). In the IVF/ICSI group, compared with the spontaneous-conception group, loss of one or both twins occurred twice as often (29% vs 14%; P = 0.001) and there was a higher risk of second-trimester miscarriage (8% vs 1%; P = 0.002).

CONCLUSIONS

MCDA twins conceived after IVF/ICSI have lower overall survival rates and higher rates of second-trimester miscarriage than do spontaneously conceived MCDA twins. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Early prognostic factors of outcomes in monochorionic twin pregnancy: systematic review and meta-analysis

BACKGROUND

Monochorionic twin pregnancies are high-risk, however at present, no screening test is available to predict which monochorionic twin pregnancy will develop complications.

OBJECTIVE

We sought to assess ability of first-trimester pregnancy-related factors (ultrasound measurements, maternal characteristics, biomarkers) to predict complications in monochorionic twin pregnancies.

DATA SOURCES

Data sources were MEDLINE, Embase, ISI Web of Science, CINAHL, the Cochrane Central Registration of Controlled Trials and Research Registers, and Google Scholar, from inception to May 12, 2017. Gray literature and bibliographies of articles were checked.

STUDY ELIGIBILITY CRITERIA

Studies that reported ultrasound measurements, maternal characteristics, or potential biomarkers, measured in the first trimester in monochorionic-diamniotic twin pregnancies, where the potential prognostic ability between the variable and twin-twin transfusion syndrome, growth restriction, or intrauterine fetal death could be assessed, were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Quality assessment was evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology checklist by 2 reviewers independently. For meta-analysis, odds ratios using a random effects model, or standardized mean difference were calculated. If a moderate association was found, the prognostic ability was evaluated by calculating the sensitivity and specificity. Risk of heterogeneity was reported as I² and publication bias was visually assessed by funnel plots and quantitatively by Egger test.

RESULTS

In all, 48 studies were eligible for inclusion. Twenty meta-analyses could be performed. A moderate association was demonstrated in 3 meta-analyses, between: nuchal translucency >95th centile in one/both fetuses and twin-twin transfusion syndrome (odds ratio, 2.29 [95% confidence interval, 1.05-4.96], I² = 6.6%, 4 studies, 615 pregnancies); crown-rump length discordance ≥10% and twin-twin transfusion syndrome (odds ratio, 2.43 [95% confidence interval, 1.13-5.21], I² = 14.1%, 3 studies, 708 pregnancies); and maternal ethnicity and twin-twin transfusion syndrome (odds ratio, 2.12 [95% confidence interval, 1.17-3.83], I² = 0.0%, 5 studies, 467 pregnancies), but none demonstrated a prognostic ability for any outcome under investigation.

CONCLUSION

It is not currently possible to predict adverse outcomes in monochorionic twin pregnancies. We have revealed a lack of research investigating first-trimester biomarkers in monochorionic twin pregnancies. Different assessment methods and definitions of each variable and outcome were an issue and this highlights the need for a large cohort study to evaluate these factors.

Severe gyration and migration disorder in fetofetal transfusion syndrome: two case reports and a review of the literature on the neurological outcome of children with lesions on neuroimaging

INTRODUCTION

Fetofetal transfusion syndrome is a dreaded cause of morbidity and mortality in monochorionic pregnancies.

CASE REPORTS

We present two pairs of twins one of which we have followed for more than 6 years. The donors suffer from cerebral palsy, orofacial, and motor problems, and both are significantly smaller than their recipient twins. Interestingly, cranial MRI revealed medial frontal lobe polymicrogyria, ventriculomegaly, and decreased thickness in both parietal lobes in both donors. We suggest this as a possible feature of fetofetal transfusion syndrome.

REVIEW

A minireview of the literature on neuroimaging and neurodevelopmental outcome in fetofetal transfusion syndrome is presented.

CONCLUSION

While the close resemblance of the imaging features of both cases is likely incidental further study of a connection between migration and gyration disorders and fetofetal transfusion syndrome is warranted.

Musical Interests and Talent: Twin Jazz Musicians and Twin Studies/Twin Research: Loss of a Preterm Multiple; Conjoined Twin Conception; Depression in Fathers of Twins; Twin-to-Twin Transfusion Syndrome/Twin News: High-Achieving Twins; Twin Children of a Tennis Star; Conjoined Twin Separation; Twin Delivery to a Giant Panda

Findings from twin studies of musical interests and talent are reviewed as a backdrop to the lives and careers of twin jazz musicians, Peter and Will Anderson. The Anderson twins exemplify many aspects of twin research, namely their matched musical abilities, shared musical interests, and common career. This overview is followed by reviews of studies and case reports of bereavement in families who have lost a preterm multiple birth infant, the conception of conjoined twins following in vitro fertilization (IVF), depression in fathers of twins, and twin-to-twin transfusion incidence in monochorionic-diamniotic IVF twin pairs. Twins highlighted in the media include high-achieving identical female twins with nearly identical academic standing, tennis star Roger Federer's two sets of identical twin children, surgical separation of craniopagus conjoined twins, and the rare delivery of twins to a 23-year-old giant panda.

Future Directions in the Management of Twin-to-Twin Transfusion Syndrome

Twin-to-twin transfusion syndrome (TTTS) is the major complication of monochorionic (MC) pregnancy. The outcomes of this condition have been significantly improved after the introduction and widespread uptake of fetoscopic laser ablation over the last decade. However, there is still a significant fetal loss rate and morbidity associated with this condition. Improvements in the management of TTTS will require improvements in many areas. They are likely to involve refinements in the prediction of the disease and clarification of the optimum frequency of surveillance and monitoring. Improvements in training for fetoscopic surgery as well as in the technique of fetoscopic laser ablation may lead to better outcomes. New technologies as well as a better understanding of the pathophysiology of TTTS may lead to adjuvant medical therapies that may also improve short- and long-term results.