Epidemiology of multiple pregnancy and the effect of assisted conception

Pregnancy outcomes of monochorionic diamniotic and dichorionic diamniotic twin pregnancies conceived by assisted reproductive technology and conceived naturally: a study based on chorionic comparison

OBJECTIVE

To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived naturally.

METHODS

We retrospectively analyzed the data on twin pregnancies conceived by ART from January 2015 to January 2022,and compared pregnancy outcomes of MCDA and DCDA twins conceived by ART with those of MCDA and DCDA twins conceived naturally, pregnancy outcomes between MCDA and DCDA twins conceived by ART, and pregnancy outcomes of DCT and TCT pregnancies reduced to DCDA pregnancies with those of DCDA pregnancies conceived naturally.

RESULT

MCDA pregnancies conceived by ART accounted for 4.21% of the total pregnancies conceived by ART and 43.81% of the total MCDA pregnancies. DCDA pregnancies conceived by ART accounted for 95.79% of the total pregnancies conceived by ART and 93.26% of the total DCDA pregnancies. Women with MCDA pregnancies conceived by ART had a higher premature delivery rate, lower neonatal weights, a higher placenta previa rate, and a lower twin survival rate than those with MCDA pregnancies conceived naturally (all p < 0.05). Women with DCDA pregnancies conceived naturally had lower rates of preterm birth, higher neonatal weights, and higher twin survival rates than women with DCDA pregnancies conceived by ART and those with DCT and TCT pregnancies reduced to DCDA pregnancies (all p < 0.05).

CONCLUSION

Our study confirms that the pregnancy outcomes of MCDA pregnancies conceived by ART are worse than those of MCDA pregnancies conceived naturally. Similarly, the pregnancy outcomes of naturally-conceived DCDA pregnancies are better than those of DCDA pregnancies conceived by ART and DCT and TCT pregnancies reduced to DCDA pregnancies.

How does the need for IVF affect pregnancy complications among multiple gestations? The study of a large American population database including almost 100,000 multiple gestations

Objective

This study's aim is to compare pregnancy outcomes in multifetal gestations that were conceived spontaneously compared to in vitro fertilization (IVF). Few population-based studies have addressed this topic.

Study design

This is a retrospective cohort study using the Health Care Cost and Utilization Project-Nationwide Inpatient Sample (HCUP-NIS) database. Our study cohort included 90,552 multifetal gestations conceived spontaneously and 3219 IVF conceptions, from 2008 to 2014, inclusively. Multivariate logistic regression analyses were performed comparing maternal and neonatal outcomes, whilst adjusting for confounding variables. Subject was conducted using ICD-9 codes for multifetal gestation: 651. X and 76.1 and ICD-9 code for IVF: 23.85. Each pregnancy was included once.

Results and conclusion

IVF multifetal gestations had increased risk of pregnancy-induced hypertension (aOR 1.31, 95 % CI 1.20-1.43), gestational hypertension (aOR 1.21, 95 % CI 1.04-1.41), preeclampsia (aOR 1.31, 95 % CI 1.19-1.45), gestational diabetes (aOR 1.26, 95 % CI 1.13-1.41) and placenta previa (aOR 1.7, 95 % CI 1.32-2.19). IVF delivery outcomes were more likely complicated by cesarean section (aOR 1.21, 95 % CI 1.10-1.33), preterm premature rupture of membranes (aOR 1.33, 95 % CI 1.16-1.52), chorioamnionitis (aOR 1.71, 95 % CI 1.37-2.14), postpartum hemorrhage (aOR 1.44, 95 % CI 1.26-1.63) and transfusions (aOR 1.48, 95 %CI 1.26-1.74). IVF neonatal outcomes were more likely complicated by small for gestational age (aOR 1.26, 95 % CI 1.12-1.41) and congenital anomalies (aOR 1.82, 95 % CI 1.29-2.57). IVF was not found to increase risks of eclampsia, preterm delivery, operative vaginal delivery, hysterectomy, or intrauterine fetal demise.IVF increased the risk of pregnancy, delivery, and neonatal outcomes in multifetal pregnancies with risks increased from 20 % to 70 %. The role of infertility versus the need for IVF and the type of IVF protocol used should be further evaluated.

Risk factors for adverse outcomes in twin pregnancies: a narrative review

PURPOSE

Globally, the incidence of twin pregnancies is rising owing to the use of assisted reproductive technologies (ART), emigration and deferment of pregnancy until advanced maternal age (AMA). While twin pregnancies have higher absolute risks of adverse outcomes, including miscarriage, stillbirth, neonatal death and preterm delivery, the impact of specific exposures and risk factors related to these outcomes may differ between twin pregnancies and singleton pregnancies. Regarding modifiable factors, data are sometimes based on evidence extrapolated from singleton or whole obstetric populations. Therefore, targeted evidence is required to provide care tailored to twin pregnancies to prevent adverse outcomes. We aimed to comprehensively review the association between different risk factors and adverse outcomes in twin pregnancies, including data on chorionicity, and to compare these to singletons.

MATERIALS AND METHODS

This review examines the risks associated with chorionicity, AMA, body mass index (BMI), socioeconomic and ethnic inequalities, maternal smoking, use of ART, maternal perception of fetal movement, and maternal comorbidities, including hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM). Adverse outcomes reported were preterm birth, admission to the neonatal intensive care unit (NICU), stillbirth and neonatal mortality. As such, fetal mortality and morbidity will be under-represented, as pregnancy loss before 22-24 weeks is omitted.

RESULTS

Monochorionicity increases the risk of stillbirth, NICU admission, and preterm delivery in twin pregnancy. AMA predisposes twin pregnancies to higher risks of mortality, admission to the NICU, and preterm birth than singleton pregnancies do. Conversely, the impact of BMI, socioeconomic inequalities, smoking, ART, and HDP on adverse outcomes appears to be lower in twin pregnancies than in singleton pregnancies. This attenuation might be explained by the higher baseline risk of adverse outcomes such as preterm birth in twin pregnancies. Some exposures, such as ART use and GDM, appear to be "protective" against perinatal mortality in twin pregnancies, despite being established risk factors for adverse outcomes in singleton pregnancies, potentially related to access to specialist care. There is a paucity of evidence available to counsel mothers of twin pregnancies regarding reduced fetal movement.

CONCLUSIONS

Overall, the risk factors for adverse pregnancy outcomes differ between twin and singleton pregnancies. This highlights the need for further studies to examine the association between risk factors and adverse outcomes in twin pregnancies. The resulting data would facilitate tailored guidance for twin pregnancies, contribute to improved antenatal care, and inform wider public health strategies.

Blastocyst Transplantation Strategies in Women of Different Ages

(1) Background: Single blastocyst transfers (SBT) and double blastocyst transfers (DBT) are widely used in clinical practice. The objective of this study was to investigate the application of these two strategies in women of different ages. (2) Methods: Analysis was carried out on 5477 frozen embryo transfer cycles of women in different ages. All the cycles were divided into three groups according to the age of the included women: <35, 35-39, and >39. The live birth rate (LBR) and multiple birth rate (MBR) between the SBT and DBT among these groups, respectively, were compared. (3) Results: In the women < 35 group, the LBR was similar in SBT and DBT, but the MBR was higher in DBT than SBT. In women 35-39, with >10 oocytes retrieved, the MBR in DBT was significantly higher than SBT, but there was no significant difference in LBR between the two groups; with ≤10 oocytes retrieved, the LBR in DBT were significantly higher than SBT, but the MBT was not significantly different between the two groups. In women > 39, the LBR and MBR were lower in the SBT than DBT, but the differences were not statistically significant. (4) Conclusions: Selective SET is appropriate for most young women, whereas older women are advised to make individualized choices based on the number of oocytes retrieved and blastocyst quality.

Effects of antenatal corticosteroids on neonatal outcomes in twin and singleton pregnancies: a Korean national cohort study

OBJECTIVE

To investigate whether effects of antenatal corticosteroids on neonatal outcomes in preterm infants with very low birth weight were different by plurality.

DESIGN

Nationwide prospective cohort study.

PATIENTS

Twins and singletons with very low birth weight (<1500 g) who were born between 23+0 and 33+6 weeks of gestation and registered in the Korean Neonatal Network from January 2014 to December 2019.

MAIN OUTCOME MEASURES

Morbidity and mortality before discharge from neonatal intensive care unit.

RESULTS

Among a total of 9531 preterm infants with very low birth weight, there were 2364 (24.8%) twins and 7167 (75.2%) singletons. While 83.9% of singletons were exposed to at least one dose of antenatal corticosteroids, so were 87.9% of twins.Interaction analysis demonstrated that there was no significant difference in the effect of antenatal corticosteroids on morbidities or mortality between twins and singletons in either gestational age group (23-28 weeks or 29-33 weeks).Antenatal corticosteroids significantly decreased the risk of surfactant use (adjusted relative risk (aRR): 0.972 (95% CI: 0.961 to 0.984)), high-grade intraventricular haemorrhage (aRR: 0.621 (95% CI: 0.487 to 0.794)), periventricular leucomalacia (aRR: 0.728 (95% CI: 0.556 to 0.954)) and mortality (aRR: 0.758 (95% CI: 0.679 to 0.846)) in the gestational age group of 23-28 weeks. In the gestational age group of 29-33 weeks, antenatal corticosteroids significantly decreased the risk of surfactant use (aRR: 0.914 (95% CI: 0.862 to 0.970)) and mortality (aRR: 0.409 (95% CI: 0.269 to 0.624)) but increased the risk of sepsis (aRR: 1.416 (95% CI: 1.018 to 1.969)).

CONCLUSION

This study demonstrates that effect of antenatal corticosteroids on neonatal outcomes of preterm infants with very low birth weight does not differ significantly by plurality (twin or singleton pregnancy).

Mode of birth in monochorionic versus dichorionic twin pregnancies: a retrospective study from a large tertiary centre in Germany

Background

Optimal mode of birth for twins, in particular monochorionic twins, has been the subject of much debate. This retrospective study compared maternal and newborn outcomes after vaginal birth in monochorionic and dichorionic twins, utilizing a large institutional database.

Methods

Retrospective analysis focusing on 98 monochorionic-diamniotic (MC-DA) and 540 dichorionic-diamniotic (DC-DA) twin births extracted from the perinatal database of a large German hospital. Pregnancies ≥36 weeks of gestation with two viable foetuses born between 2004 and 2014 divided into planned vaginal and planned caesarean delivery were included. Descriptive analysis was performed for maternal characteristics. Odds ratios (OR) with 95% confidences intervals (CI) tested the predictive effect of vaginal birth on neonatal and maternal outcomes.

Results

51.0% MC-DA and 46.7% DC-DA twin pregnancies were planned vaginal births and 44.0% MC-DA mothers and 43.7% DC-DA mothers actually gave birth vaginally. The overall rate of caesarean section (CS) during the years under observation was 79.6% for MC-DA and 77.0% for DC-DA pregnancies. There were no significant differences in neonatal outcome between the subsamples, although acidosis was observed more often in the second DC-DA twin and Apgar scores < 7 were observed more often in MC-DA twins.

Conclusion

Vaginal birth may be recommended as an option to women with monochorionic twins as no significant differences in outcomes were found between MC-DA and DC-DA twins. However, over half of planned vaginal twin births resulted in CS.

Follicular fluid steroid and gonadotropic hormone levels and mitochondrial function from exosomes predict embryonic development

PURPOSE

Human follicular fluid (FF) is a complex biological fluid that contributes to the micro-environment of oocyte development. The aim of this study was to evaluate the role of steroid and gonadotropic hormones levels and mitochondrial function in embryo development during in vitro fertilization cycles.

METHODS

This was a cohort study of 138 women receiving IVF/ICSI, including 136 FF samples from 109 infertile women. FF steroid and gonadotropic hormones levels were tested by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and immunoassays. The mRNA expression levels of mitochondrial electron transport chain (ETC) complex genes from FF exosomes were detected by qPCR.

RESULTS

Analysis of these individual FF concentrations revealed that LH and FSH concentrations were higher in follicles in which the oocyte developed into a top quality (TQ) blastocyst (LH: 9.44 ± 2.32mIU/ml, FSH: 9.32 ± 1.01mIU/ml) than those in which there was a failure of fertilization (LH: 5.30 ± 0.84mIU/ml, FSH: 6.91 ± 0.62mIU/ml). In contrast, follicular cortisone concentrations were lower for oocytes that resulted in a TQ blastocyst (12.20 ± 0.82mIU/ml). The receiver operating characteristic analysis showed that FF LH and FSH levels predicted TQ blastocyst with excellent AUC value of 0.711 and 0.747. Mitochondrial ETC complex I and III mRNA levels were increased in the FF exosomes of TQ blastocyst. Correlation analysis showed that mRNA levels of ETC complex I was positively correlated with LH and FSH levels in FF.

CONCLUSION

The levels of FF steroid and gonadotropic hormones from single follicle can predetermine subsequent embryo development to some extent. Furthermore, impaired exosome mitochondrial dysfunction is a potiential event that causes hormone change in embryo development.

Dispensing of clomiphene citrate to treat infertility: medication supplied and population prevalence of assisted pregnancies and multiple births

OBJECTIVE

To determine the proportion of pregnancies resulting in birth that were conceived with the use of clomiphene citrate (CC) and the frequency of multiple pregnancy.

DESIGN

Whole-of-population cohort study, constructed through data linkage. Comprehensive Australian Government records of dispensed medications were linked to state Perinatal Registry records for all births of at least 20 weeks' gestation.

SETTING

The state of South Australia.

PATIENT(S)

Women who maintained pregnancy for at least 20 weeks and gave birth between July 2003 and December 2015, a total of 150,713 women with 241,561 pregnancies.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy occurring in proximity to CC, defined as dispensing from 90 days before to the end of a conception window derived from newborn date of birth and gestational age.

RESULT(S)

Linkage to dispensed prescription records was achieved for 97.9% of women. Women who conceived with CC tended to be older and socioeconomically advantaged and more likely than other women to have a history of miscarriage. Ongoing pregnancies associated with CC comprised 1.6% of the total; 5.7% were multiple births (mostly twins, 94.6%) compared with 1.5% in the remainder (98.5% twins).

CONCLUSION(S)

In South Australia, 1.6% of pregnancies (1 in 60) of at least 20 weeks' gestation were conceived proximal to CC dispensing. Of these, 5.7% were multiple pregnancies. This takes the proportion of women who achieved an ongoing pregnancy with medical assistance from 4.4%, based on reports from assisted reproductive technology clinics, to 6% in total.

Association between pregravid liver enzyme levels and gestational diabetes in twin pregnancies: a secondary analysis of national cohort study

Multiple pregnancies are prone to gestational diabetes mellitus (GDM). This study investigated the association between pregravid liver enzyme levels and the development of GDM in a twin pregnancy. Women who had the National Health Screening Examination and delivered their twin babies within one year were enrolled. Pregravid liver enzyme levels were divided into high and low level. Risks for developing GDM by high levels of liver enzymes were analyzed, in subgroups by pregravid obesity or metabolic syndrome. Among the 4348 twin pregnancies, 369 women (8.5%) developed GDM not requiring insulin treatment (GDM - IT), and 119 women (2.7%) developed GDM requiring insulin treatment(GDM + IT). High levels of pregravid GGT and ALT were related to risks of GDM + IT not only in women with obesity or metabolic syndrome (odds ratio[OR] 6.348, 95% confidence interval [CI] 2.579-15.624 and OR 6.879, 95% CI 2.232-21.204, respectively), but also in women without obesity (OR 3.05, 95% CI 1.565-5.946) or without metabolic syndrome (OR 3.338, 95% CI 1.86-5.992), compared to in women with low levels of those. However, there were no significant associations in the pregravid ALT and GGT levels and risks for development of GDM - IT, unrelated to pregravid obesity or metabolic syndrome. Therefore, this study suggests that women with high levels of pregravid GGT and ALT need to recognize their increased risk of GDM + IT, regardless of pregravid obesity or MetS, when they get pregnant twin.

Advanced trophectoderm quality increases the risk of a large for gestational age baby in single frozen-thawed blastocyst transfer cycles

STUDY QUESTION

Does trophectoderm (TE) quality affect birthweight after single frozen-thawed blastocyst transfer?

SUMMARY ANSWER

Transfer of single blastocyst with advanced TE quality was associated with higher birthweight and increased risk of a large for gestational age (LGA) baby.

WHAT IS KNOWN ALREADY

Transfer of blastocysts with advanced TE quality results in higher ongoing pregnancy rates and a lower miscarriage risk. However, data on the relationship between TE quality and birthweight are still lacking.

STUDY DESIGN, SIZE, DURATION

This retrospective cohort study at a tertiary-care academic medical center included 1548 singleton babies born from single frozen-thawed blastocyst transfer from January 2011 to June 2019.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Babies were grouped into four groups according to embryo expansion (Stages 3, 4, 5 and 6), three groups according to inner cell mass (ICM) quality (A, B and C), and three groups according to TE quality (A, B and C). Main outcomes included absolute birthweight, Z-scores adjusted for gestational age and gender, and adverse neonatal outcomes. Multivariable linear and logistic regression analyses were performed to investigate the association of neonatal outcomes with expansion stage, ICM quality and TE quality.

MAIN RESULTS AND THE ROLE OF CHANCE

As TE quality decreased, birthweight (3468.10 ± 471.52, 3357.69 ± 522.06, and 3288.79 ± 501.90 for A, B and C, respectively, P = 0.002), Z-scores (0.59 ± 1.07, 0.42 ± 1.04, and 0.27 ± 1.06 for A, B and C, respectively, P = 0.002) and incidence of LGA (28.9%, 19.7% and 17.4% for A, B and C, respectively, P = 0.027) decreased correspondingly. After adjusting for confounders, compared with the Grade A group, blastocysts with TE Grade B (standardized coefficients (β): -127.97 g, 95% CI: -234.46 to -21.47, P = 0.019) and blastocysts with TE grade C (β: -200.27 g, 95% CI: -320.69 to -79.86, P = 0.001) resulted in offspring with lower birthweight. Blastocysts with TE grade C brought babies with lower Z-scores than TE Grade A (β: -0.35, 95% CI: -0.59 to -0.10, P = 0.005). Also, embryos with TE Grade B (adjusted odds ratio (aOR):0.91, 95% CI: 0.84 to 0.99, P = 0.033) and embryos with TE Grade C (aOR : 0.89, 95% CI: 0.81 to 0.98, P = 0.016) had lower chance of leading to a LGA baby than those with TE Grade A. No association between neonatal outcomes with embryo expansion stage and ICM was observed (all P > 0.05).

LIMITATIONS, REASONS FOR CAUTION

The retrospective design, lack of controlling for several unknown confounders, and inter-observer variation limited this study.

WIDER IMPLICATIONS OF THE FINDINGS

The study extends our knowledge of the down-stream effect of TE quality on newborn birthweight and the risk of LGA.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by National Key R&D Program of China (2018YFC1003000), National Natural Science Foundation of China (81771533 to Y.P.K. and 31200825 to L.S.) and Innovative Research Team of High-level Local Universities in Shanghai (SSMU-ZLCX20180401), Shanghai Sailing Program(21YF1423200) and the Fundamental research program funding of Ninth People's Hospital affiliated to Shanghai Jiao Tong university School of Medicine (JYZZ117). The authors declare no conflict of interest in this present study.

TRIAL REGISTRATION NUMBER

N/A.

Cerebral palsy in children born after assisted reproductive technology: a meta-analysis

BACKGROUND

Several studies have assessed the association between cerebral palsy (CP) and assisted reproductive technology (ART), but the results remain controversial. We conducted a meta-analysis to evaluate the risk of CP after ART compared with natural conceptions and to examine CP risk separately in ART singletons, multiples and preterm births.

METHODS

Web-based databases (PubMed, Embase, the Cochrane Library, and Web of Science) were searched until November 22, 2020. Studies which compare CP rates after ART with natural conceptions were included. The Newcastle-Ottawa Scale was used to assess the quality of the included studies. Effect estimates were extracted and combined using the fixed-effects or random-effects model depending on the heterogeneity test.

RESULTS

There were nine studies included in the meta-analysis. The included studies were of moderate or high quality. A significantly higher risk of CP [odds ratio (OR) = 2.17, 95% confidence interval (CI) 1.72-2.74] was found in ART children (n = 89,214) compared with naturally conceived children (n = 4,160,745). The significantly higher risk decreased when data were restricted to singletons (OR = 1.36, 95% CI 1.16-1.59) and disappeared when data were restricted to multiples (OR = 1.05, 95% CI 0.86-1.29) or preterm births (OR = 1.53, 95% CI 0.66-3.56). Subgroup and sensitivity analyses indicated that the overall results were robust.

CONCLUSIONS

The risk of CP is increased more than two-fold after ART. This increased risk is largely due to increased rates of multiple birth and preterm delivery in ART children.

Assessments of Birth Outcome of Twin Delivery and Associated Factors among Newborns in Dessie Referral Hospital, Dessie, Ethiopia, 2019

Background

There was a fast improvement of twin's birth outcomes in the past decade, but it was average in developing countries. Stillbirth, preterm birth, low birth weight, and birth asphyxia are the major contributors to poor twin birth outcomes. This study was crucial to address the gaps and clarify the outcome of twin delivery.

Objectives

To assess the birth outcome of twin delivery and associated factors among newborns who were delivered in Dessie Referral Hospital, Ethiopia, 2019.

Methods

Institutional-based retrospective cross-sectional study was employed among 385 maternal records from Nov 10/2013 to Dec 10/2019. Data were selected by using a random sampling technique. Frequencies, proportion, and summary statics were used to describe the study population. The data were entered into Epi Info and exported in the SPSS version 20 for analysis. All variables with p value < 0.20 in bivariable logistic regression analysis were considered for multivariable logistic regression analysis; adjusted odds ratio with 95% confidence interval was used to measure the association variable with p value < 0.05 which was statistically significant.

Results

This finding showed that the prevalence of twin birth outcome accounts 23.4% (95 % CI, 19.2–27.5). Low birth weight 9.1%, stillbirth 4.2%, Apgar score < 7 9.1%, and neonatal death 1 % were accounted. Hypertension disorder (95% CI, 6.01(2.43–14.87)), rural residence (95% CI 2.46(1.39–4.37)), PROM (95% CI 6.39(2.52–16.16)), and no ANC follow-up (95% CI, 13.47(2.49–72.85)) were significantly associated with adverse twin birth. Conclusions and Recommendations. Magnitude of twins' adverse birth outcome was 23.4%. Hypertension disorder, rural residence, PROM, and no ANC follow-up were significant variables for twins' adverse birth outcome. Therefore, all healthcare providers should give sustainable educations and instructions about the importance of sticking with the recommended ANC follow-up.

Does late second-trimester cervical length predict unscheduled preterm birth in asymptomatic triplet pregnancies?

OBJECTIVE

Multiple gestation increases the risk of unscheduled preterm birth (PTB), both spontaneous and indicated, leading to increased neonatal morbidity and additional healthcare costs. The purpose of this study was to determine whether cervical length (CL) assessment by 28 weeks could predict unscheduled PTB <34 weeks in triplet pregnancies. Secondary outcomes included prediction of PTB <30 weeks, prediction of PTB based on degree of cervical change and effect of ART-use on PTB.

METHODS

This was a retrospective cohort of women with triplet pregnancies. The exposure variable of interest was short cervix < 25 and <20 millimeters (mm) by 28 weeks. Maternal characteristics were described. The distribution of CLs was analyzed by the primary outcome of unscheduled PTB < 34 weeks, and by PTB <30 weeks (secondary outcome). Gestational age at delivery was compared between women with and without a short cervix. Changes in CL were compared between the groups with unscheduled PTB and those delivering ≥34 and ≥30 weeks. Statistical analyses were performed using appropriate tests.

RESULTS

Of 92 triplet pregnancies, 51 met the criteria, with 1233 total (411 shortest) CL measurements from 16 to 34 weeks' gestation. The overall rate of PTB <34 weeks was 31.4% and <30 weeks was 9.8%. The median gestational age at delivery was 32.7 (IQR 2.3) weeks. There were no statistically significant differences in rates of unscheduled PTB in women who had a short cervix and those that did not: PTB <34 weeks with CL <25 mm (p = .53) and CL <20 mm (p = .70); PTB <30 weeks with CL <25 mm (p = .38) and CL <20 mm (p = .26). The degree of cervical change from 18 to 28 weeks was not statistically significant for predicting unscheduled PTB <34 and <30 weeks. Of 70.6% of triplet pregnancies conceived by ARTs, 13.9% had unscheduled PTB <30 weeks, whereas no spontaneously-conceived pregnancies delivered <30 weeks (p = .14).

CONCLUSION

Short cervix did not predict unscheduled spontaneous PTB <34 weeks nor <30 weeks in our triplet cohort, nor did the degree of cervical change by 28 weeks predict PTB. Triplets conceived by ARTs may have an increased risk of unscheduled PTB.

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.

The maternal and perinatal implications of hypertensive disorders of pregnancy in a multiple pregnancy cohort

INTRODUCTION

Hypertensive disorders of pregnancy are common and may result in increased maternal and neonatal morbidity and mortality. Multiple pregnancies confer an increased risk of development of a hypertensive disorder of pregnancy. The purpose of this study was to examine a large cohort of women delivering a multiple pregnancy in a single large tertiary unit, and to evaluate the implications of hypertensive disorders of pregnancy on both maternal and perinatal outcomes.

MATERIAL AND METHODS

Retrospective study of all twin pregnancies delivered at Cork University Maternity Hospital, Ireland over a 9-year period (2009-2017). The twin pregnancies were divided according to the presence or absence of hypertensive disorder of pregnancy and the two groups were compared.

RESULTS

Maternal age >40 years, nulliparity, conception through use of a donor oocyte, and presence of obstetric cholestasis are all risk factors for the development of hypertensive disorders of pregnancy in women with a multiple pregnancy. When a hypertensive disorder complicates a twin pregnancy, it increases the incidence of iatrogenic late prematurity and neonatal hypoglycemia.

CONCLUSIONS

This study is informative for clinicians caring for women with a multiple pregnancy with its relevant data on perinatal outcomes following a diagnosis of hypertensive disorder in pregnancy.

Anti-Müllerian hormone and progesterone levels in human follicular fluid are predictors of embryonic development

BACKGROUND

Human follicular fluid is an intricate biological fluid contributing to the developing oocyte microenvironment. Accumulating evidence suggests that sex hormones present in follicular fluid (FF) may play an important role in regulating oocyte developmental potential. The aim of this study was to determine if anti-Müllerian hormone (AMH) and progesterone (P4) levels in FF are correlated with oocyte quality as defined by subsequent embryonic development.

METHODS

This was a prospective cohort study of 88 women undergoing IVF/ICSI at a university associated fertility clinic. Follicular fluid was collected from the first follicle aspirated at the time of oocyte retrieval. The corresponding oocyte was individually cultured in order to track its developmental outcome. FF-AMH and P4 concentrations from follicles where the oocyte fertilised normally and developed into a blastocyst on day 5 (Group 1: BLAST, n = 23) were compared with FF from follicles where the oocyte fertilised normally but failed to reach blastocyst stage by day 5 (Group 2: FERT, n = 19). No significant differences were observed between the two groups in terms of maternal age, body mass index, previous live births, previous pregnancy loss, number of antral follicles, number of oocytes recovered, IVF:ICSI ratio or percentage of recovered oocytes that fertilised.

RESULTS

FF-AMH and P4 levels were significantly increased in Group 1: BLAST compared to Group 2: FERT (P = 0.007 and P = 0.013 respectively). Twenty-one FF samples had an AMH level > 15 pmol/L, of which 17 related to oocytes that progressed to blastocyst stage, providing a positive prediction value (PPV) of 76.96%. Eleven FF samples had a P4 level > 60 mg/ml, of which 10 progressed to blastocyst stage, providing a PPV of 90.99%. Six samples had an AMH level > 15 pmol/L and a P4 level > 60 mg/ml, of which 100% progressed to blastocyst stage, providing a PPV of 96.83%.

CONCLUSIONS

FF-AMH and P4 levels from individual follicles can accurately predetermine subsequent embryonic development. Combining follicular fluid analysis with routine morphological assessment, could allow for a more accurate and sensitive method of determining embryonic developmental competence.

How much have the perinatal outcomes of triplet pregnancies improved over the last two decades?

Objective

This study was conducted to demonstrate the temporal trends in perinatal outcomes of triplet pregnancies over the last two decades.

Methods

The medical records of patients with triplet pregnancies at two Korean tertiary-care hospitals from 1992 to 2012 were retrospectively reviewed in regard to maternal and neonatal outcomes. The study was divided into two periods for analysis: period I (1992-2001) and period II (2003-2012).

Results

Over a 21-year period, 65 women with triplet pregnancies and 185 neonates were analyzed. Period II, when compared with period I, was associated with improved maternal outcomes, characterized by a decreased incidence of preeclampsia (31.8% vs. 2.3%, P=0.002) and anemia (68.2% vs. 30.2%, P=0.003) during pregnancy. Regarding neonatal aspects, the composite morbidity of period II was significantly decreased compared with that of period I, as assessed with a generalized estimating equation for logistic regression (26.2% vs. 8.1%, P=0.03). Multivariable analysis revealed that the gestational age at delivery and the period were significantly associated with the composite neonatal morbidity (P<0.001 and 0.007, respectively).

Conclusion

Improved neonatal morbidity was associated with a higher gestational age at delivery and with the more recent decade.

Perinatal outcome of twin pregnancies according to maternal age

Objective

To investigate the perinatal outcomes of twin pregnancies according to maternal age.

Methods

This is a retrospective cohort study of twin pregnancies delivered ≥24 weeks' gestation at a tertiary academic hospital from 1995 to 2016. Subjects were categorized into 5 groups according to maternal age: <25, 25–29, 30–34, 35–39, and ≥40 years. Maternal and neonatal outcomes of each maternal age group were analyzed using the Jonckheere-Terpstra test and the linear-by-linear association test.

Results

A total of 1,936 twin pregnant women were included, of which 47 (2.4%), 470 (24.3%), 948 (49.0%), 417 (21.5%), and 54 (2.7%) women were aged <25, 25–29, 30–34, 35–39, and ≥40 years, respectively. Higher maternal age was significantly associated with a higher rate of dichorionic twins and a higher risk of gestational diabetes and placenta previa. However, rates of preterm labor, preterm premature rupture of membranes, cervical incompetence, preterm delivery, preeclampsia, placenta abruption, and cesarean section were not associated with maternal age. Birth weight increased and the rate of admission to the neonatal intensive care unit (NICU) decreased with older maternal age, but other neonatal outcomes did not change with age. Maternal age was significantly associated with a lower rate of NICU admission after controlling for potential confounding factors in multivariable analysis.

Conclusion

Advanced maternal age in twin pregnancies was associated with increased risk of gestational diabetes, placenta previa, and higher birth weight but a lower rate of NICU admission. However, other outcomes were not significantly associated with maternal age.

Prevalence, antenatal management and perinatal outcome of monochorionic monoamniotic twin pregnancy: a collaborative multicenter study in England, 2000-2013

OBJECTIVES

To determine the prevalence of monochorionic monoamniotic (MCMA) twin pregnancy and to describe perinatal outcome and clinical management of these pregnancies.

METHODS

In this multicenter cohort study, the prevalence of MCMA twinning was estimated using population-based data on MCMA twin pregnancies, collected between 2000 and 2013 from 11 Northern Survey of Twin and Multiple Pregnancy (NorSTAMP) maternity units. Pregnancy outcome at < 24 weeks' gestation, antenatal parameters and perinatal outcome (from ≥ 24 weeks to the first 28 days of age) were analyzed using combined data on pregnancies confirmed to be MCMA from NorSTAMP and the Southwest Thames Region of London Obstetric Research Collaborative (STORK) multiple pregnancy cohort for 2000-2013.

RESULTS

The estimated total prevalence of MCMA twin pregnancies in the North of England region was 8.2 per 1000 twin pregnancies (59/7170), and the birth prevalence was 0.08 per 1000 pregnancies overall (singleton and multiple). Using combined data from NorSTAMP and STORK, the rate of fetal death (at < 24 weeks' gestation), including terminations of pregnancy and selective feticide, was 31.8% (54/170); the overall perinatal mortality rate was 14.7% (17/116), ranging from 69.2% at < 30 weeks to 4.5% at ≥ 33 weeks' gestation. MCMA twins that survived in utero beyond 24 weeks were delivered, usually by Cesarean section, at a median of 33 (interquartile range, 32-34) weeks of gestation.

CONCLUSIONS

In MCMA twins surviving beyond 24 weeks of gestation, there was a higher survival rate compared with in previous decades, presumably due to early diagnosis, close surveillance and elective birth around 32-34 weeks of gestation. High perinatal mortality at early gestations was attributed mainly to extreme prematurity due to preterm spontaneous labor. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Advanced maternal age and perinatal outcome in twin pregnancies: a meta-analysis

Objective: The current meta-analysis evaluates the perinatal outcomes of twin pregnancies in pregnant women 35 years or older (advanced maternal age) compared with less than 35 years at the time of delivery.Study design: A search was conducted up to March 2018. Electronic databases that were used in our research included; Embase (NO Medline), Ovid Medline, Cochrane Central Register of Controlled Trials, and Web of Science. Inclusion criteria were twin pregnancies; a comparison between pregnant women aged ≥35 years versus <35 years at the time of delivery and reported perinatal outcomes. Review articles, case reports, and case series were excluded. Data analysis was performed using the Cochrane's Review Manager 5.3 software. Pooled odds ratio for dichotomous outcomes or mean difference for continuous outcomes were calculated using a random effects model. I² test was performed to assess heterogeneity. The quality of each accepted article was assessed using the Newcastle-Ottawa Scale.Results: Our search yielded 1622 publications, of which 25 were assessed for eligibility. A total of 13 studies met our final inclusion criteria. In twin pregnancies, advanced maternal age was associated with a lower incidence of preterm birth prior to 37 weeks' gestation (OR 0.89 [95% CI 0.83-0.95]) compared with women under 35 years at the time of delivery. Gestational diabetes (OR 1.57 [95% CI 1.24-1.98]) and cesarean deliveries (OR 1.69 [95% CI 1.52-1.87]) were significantly higher among women in the advanced maternal age group. All other measured outcomes, such as preterm delivery before 32 weeks' gestation, hypertension disorders, small for gestational age, birth weight under 2500 or 1500 g, need for neonatal intensive care admission and perinatal death were comparable between the groups.Conclusions: This meta-analysis implies that advanced maternal age mothers in the setting of twin pregnancy is associated with comparable outcomes to nonadvanced maternal age mothers. The only outstanding differences were higher rates of GDM and cesarean deliveries in the advanced maternal age (AMA) group.

Reproductive ageing-turning back the clock?

BACKGROUND

Unintended childlessness is a distressing, and often unintended, consequence of delayed childbearing and reproductive ageing. The average maternal age at first birth has risen steadily in many industrialised countries since the 1980s. There are many societal factors involved in the decision to postpone motherhood. As a result, many women are postponing having children until it is too late. In this review, we aim to summarise the reasons behind delayed childbearing, the impact of delayed childbearing and the scientific advances that seek to reverse reproductive ageing and ensure reproductive autonomy for women.

METHODS

An extensive literature search of PubMed was conducted to include all published articles on delayed childbearing and the consequences of reproductive ageing. Secondary articles were identified from key paper reference listings.

CONCLUSION

If the current reproductive trends continue, many women will find themselves in the harrowing position of being unintentionally childless. In addition, many will inevitably turn to assisted reproductive technologies in an effort to protect and preserve their reproductive autonomy. However, it is not always possible to reverse the effects of reproductive ageing.

Fetal cardiac remodeling in twin pregnancy conceived by assisted reproductive technology

OBJECTIVE

Recent data suggest that singleton fetuses conceived by assisted reproductive technology (ART) present cardiovascular remodeling that may persist postnatally. Twin pregnancies are more frequent in the ART population and are associated with increased adverse perinatal outcomes, such as hypertensive disorders, gestational diabetes and preterm birth. However, it is unknown whether cardiac remodeling is also present in twin pregnancies conceived by ART. Our aim was to assess the presence of fetal cardiac remodeling and dysfunction in twin pregnancies conceived by ART as compared with those conceived spontaneously (SC).

METHODS

This was a prospective cohort study including 50 dichorionic twin fetuses conceived by ART and 50 SC twin fetuses. The study protocol included collection of baseline/perinatal data and a fetal ultrasound examination at 28-30 weeks' gestation, including assessment of estimated fetal weight, fetoplacental Doppler and fetal echocardiography. Measurements of atrial area, atrial/heart ratio, ventricular sphericity index, free wall thickness, mitral and tricuspid annular plane systolic excursions, and systolic and early diastolic peak velocities were assessed. Multilevel analyses were used to compare perinatal and ultrasonographic parameters. Comparisons of echocardiographic variables were adjusted for parental age, paternal body mass index and incidence of pre-eclampsia.

RESULTS

Compared with SC twins, ART twin fetuses showed significant cardiac changes, predominantly affecting the right heart, such as dilated atria (right atrial/heart area: 15.7 ± 3.1 vs 18.4 ± 3.2, P < 0.001), more globular ventricles (right ventricular sphericity index: 1.57 ± 0.25 vs 1.41 ± 0.23, P = 0.001) and thicker myocardial walls (septal wall thickness: 2.57 ± 0.45 mm vs 2.84 ± 0.41 mm, P = 0.034) together with reduced longitudinal motion (tricuspid annular plane systolic excursion: 6.36 ± 0.89 mm vs 5.18 ± 0.93 mm, P < 0.001).

CONCLUSIONS

ART twin fetuses present signs of cardiac remodeling and dysfunction. These changes are similar to those observed in ART singletons and reinforce the concept of fetal cardiac programing in ART. These results open opportunities for early detection and intervention in infants conceived by ART. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Tehran Survey of Potential Risk Factors for Multiple Births

Background

The multiple pregnancy incidence is increasing worldwide. This increased incidence is concerning to the health care system. This study aims to determine the frequency of multiple pregnancy and identify factors that affect this frequency in Tehran, Iran.

MATERIALS AND METHODS

This cross-sectional study included 5170 mothers in labor between July 6-21, 2015 from 103 hospitals with Obstetrics and Gynecology Wards. The questionnaire used in this study consisted of five parts: demographic characteristics; information related to pregnancy; information related to the infant; information regarding the multiple pregnancy; and information associated with infertility. We recruited 103 trained midwives to collect data related to the questionnaire from eligible participants through an interview and medical records review. Frequencies and odds ratios (OR) for the association between multiple pregnancy and the selected characteristics (maternal age, economic status, history of multiple pregnancy in first-degree relatives, and reproductive history) were computed by multiple logistic regression. Stata software, version 13 (Stata Corp, College Station, TX, USA) was used for all statistical analyses.

RESULTS

Multiple pregnancy had a prevalence of 1.48% [95% confidence interval (CI): 1.19-1.85]. After controlling for confounding variables, we observed a significant association between frequency of multiple pregnancy and mother's age (OR=1.04, 95% CI: 1.001-1.09, P=0.044), assisted reproductive technique (ART, OR=6.11, 95% CI: 1.7- 21.97, P=0.006), and history of multiple pregnancy in the mother's family (OR=5.49, 95% CI: 3.55-9.93, P=0.001).

CONCLUSION

The frequency of multiple pregnancy approximated results reported in previous studies in Iran. Based on the results, we observed significantly greater frequency of multiple pregnancy in older women, those with a history of ART, and a history of multiple pregnancy in the mother's family compared to the other variables.

Bed rest with and without hospitalisation in multiple pregnancy for improving perinatal outcomes

BACKGROUND

Strict or partial bed rest in hospital or at home is commonly recommended for women with multiple pregnancy to improve pregnancy outcomes. In order to advise women to rest in bed for any length of time, a policy for clinical practice needs to be supported by reliable evidence and weighed against possible adverse effects resulting from prolonged activity restriction.

OBJECTIVES

The objective of this review is to assess the effectiveness of bed rest in hospital or at home to improve perinatal outcomes in women with a multiple pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 May 2016), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (30 May 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

We selected all individual and cluster-randomised controlled trials evaluating the effect of strict or partial bed rest at home or in hospital compared with no activity restriction during multiple pregnancy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, extracted data and methodological quality. We evaluated the quality of the evidence using the GRADE approach and summarised it in 'Summary of findings' tables.

MAIN RESULTS

We included six trials, involving a total of 636 women with a twin or triplet pregnancy (total of 1298 babies). We assessed all of the included trials as having a low risk of bias for random sequence generation. Apart from one trial with an unclear risk of bias, we judged all remaining trials to be of low risk of bias for allocation concealment.Five trials (495 women and 1016 babies) compared strict bed rest in hospital with no activity restriction at home. There was no difference in the risk of very preterm birth (risk ratio (RR) 1.02, 95% confidence interval (CI) 0.66 to 1.58, five trials, 495 women, assuming complete correlation between twins/triplets, low-quality evidence), perinatal mortality (RR 0.65, 95% CI 0.35 to 1.21, five trials, 1016 neonates, assuming independence between twins/triplets, low-quality evidence) and low birthweight (RR 0.95, 95% CI 0.75 to 1.21, three trials, 502 neonates, assuming independence between twins/triplets, low-quality evidence). We observed no differences for the risk of small-for-gestational age (SGA) (RR 0.75, 95% CI 0.56 to 1.01, two trials, 293 women, assuming independence between twins/triplets, low-quality evidence) and prelabour preterm rupture of the membrane (PPROM) (RR 1.30, 95% CI 0.71 to 2.38, three trials, 276 women, low-quality evidence). However, strict bed rest in hospital was associated with increased spontaneous onset of labour (RR 1.05, 95% CI 1.02 to 1.09, P = 0.004, four trials, 488 women) and a higher mean birthweight (mean difference (MD) 136.99 g, 95% CI 39.92 to 234.06, P = 0.006, three trials, 314 women) compared with no activity restriction at home.Only one trial (141 women and 282 babies) compared partial bed rest in hospital with no activity restriction at home. There was no evidence of a difference in the incidence of very preterm birth (RR 2.30, 95% CI 0.84 to 6.27, 141 women, assuming complete correlation between twins, low-quality evidence) and perinatal mortality (RR 4.17, 95% CI 0.90 to 19.31, 282 neonates, assuming complete independence twins, low-quality evidence) between the intervention and control group. Low birthweight was not reported in this trial. We found no differences in the risk of PPROM and SGA between women receiving partial bed rest and the control group (low-quality evidence). Women on partial bed rest in hospital were less likely to develop gestational hypertension compared with women without activity restriction at home (RR 0.30, 95% CI 0.16 to 0.59, P = 0.0004, 141 women).Strict or partial bed rest in hospital was found to have no impact on other secondary outcomes. None of the trials reported on costs of the intervention or adverse effects such as the development of venous thromboembolism or psychosocial effects.

AUTHORS' CONCLUSIONS

The evidence to date is insufficient to inform a policy of routine bed rest in hospital or at home for women with a multiple pregnancy. There is a need for large-scale, multicenter randomised controlled trials to evaluate the benefits, adverse effects and costs of bed rest before definitive conclusions can be drawn.

Maternal psychosocial consequences of twins and multiple births following assisted and natural conception: a meta-analysis

The aim of this meta-analysis is to provide new evidence on the effects on maternal health of multiple births due to assisted reproductive technology (ART). A bibliographic search was undertaken using PubMed, PsycINFO, CINAHL and Science Direct. Data extraction was completed using Cochrane Review recommendations, and the review was performed following PRISMA and MOOSE guidelines. Meta-analytic data were analysed using random effects models. Eight papers (2993 mothers) were included. Mothers of ART multiple births were significantly more likely to experience depression (standardized mean difference [SMD] d = 0.198, 95% CI 0.050 - 0.345, z = 2.623, P = 0.009; heterogeneity I(2) = 36.47%), and stress (SMD d = 0.177, 95% CI 0.049 - 0.305, P = 0.007; heterogeneity I(2) = 0.01%) than mothers of ART singletons. No difference in psychosocial distress (combined stress and depression) (SMD d = 0.371, 95% CI -0.153 - 0.895; I(2) = 86.962%, P = 0.001) or depression (d = 0.152, 95% CI -0.179 - 0.483: z = 0.901; I(2) = 36.918%) were found between mothers of ART and naturally conceived multiple births. In conclusion, mothers of ART multiple births were significantly more likely to have depression and stress than mothers of ART singletons, but were no different from mothers of naturally conceived multiples.

Dizygotic twin pregnancies after medically assisted reproduction and after natural conception: maternal and perinatal outcomes

OBJECTIVE

To compare maternal and perinatal outcomes in dizygotic twin pregnancies conceived after medically assisted reproduction (MAR) with outcomes after natural conception (NC).

DESIGN

Nationwide registry based study.

SETTING

Academic medical center.

PATIENT(S)

Primiparous women who delivered opposite sex twins between January 2000 and December 2012 in the Netherlands, comprising dizygotic twin pregnancies: 6,694 women, 470 after ovulation induction (OI), 511 after intrauterine insemination with controlled ovarian hyperstimulation (IUI-COH), 2,437 after in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI), and 3,276 after NC.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Multivariable logistic regression and generalized linear mixed models to evaluate differences in outcomes: maternal outcomes of hypertension, preeclampsia, preterm delivery, hemorrhage, and delivery mode, perinatal outcomes including small for gestational age (SGA) with birth weight <10th percentile, birth weight <1,500 g, 5-minute Apgar score <7, admission to neonatal intensive care unit, congenital anomalies, and perinatal mortality.

RESULT(S)

We found no statistically significant differences in maternal or perinatal outcomes after OI compared with NC. Women pregnant after IVF-ICSI had a lower risk for hypertension (adjusted odds ratio [aOR] 0.74; 95% confidence interval [CI], 0.66-0.83) compared with women pregnant after NC. After IUI-COH more children had Apgar scores <7 (adjusted odds ratio (aOR) 1.38; 95% confidence interval (CI) 1.05-1.81) and perinatal mortality rates were higher (aOR 1.56; 95% CI, 1.04-2.33) compared with NC. We found no differences in perinatal outcomes after IVF-ICSI compared with NC.

CONCLUSION(S)

Overall, maternal and perinatal risks other than those due to multiplicity are similar for twin pregnancies conceived after MAR and after NC.

Variations in Multiple Birth Rates and Impact on Perinatal Outcomes in Europe

OBJECTIVE

Infants from multiple pregnancies have higher rates of preterm birth, stillbirth and neonatal death and differences in multiple birth rates (MBR) exist between countries. We aimed to describe differences in MBR in Europe and to investigate the impact of these differences on adverse perinatal outcomes at a population level.

METHODS

We used national aggregate birth data on multiple pregnancies, maternal age, gestational age (GA), stillbirth and neonatal death collected in the Euro-Peristat project (29 countries in 2010, N = 5 074 643 births). We also used European Society of Human Reproduction and Embryology (ESHRE) data on assisted conception and single embryo transfer (SET). The impact of MBR on outcomes was studied using meta-analysis techniques with random-effects models to derive pooled risk ratios (pRR) overall and for four groups of country defined by their MBR. We computed population attributable risks (PAR) for these groups.

RESULTS

In 2010, the average MBR was 16.8 per 1000 women giving birth, ranging from 9.1 (Romania) to 26.5 (Cyprus). Compared to singletons, multiples had a nine-fold increased risk (pRR 9.4, 95% Cl 9.1-9.8) of preterm birth (<37 weeks GA), an almost 12-fold increased risk (pRR 11.7, 95% CI 11.0-12.4) of very preterm birth (<32 weeks GA). Pooled RR were 2.4 (95% Cl 1.5-3.6) for fetal mortality at or after 28 weeks GA and 7.0 (95% Cl 6.1-8.0) for neonatal mortality. PAR of neonatal death and very preterm birth were higher in countries with high MBR compared to low MBR (17.1% (95% CI 13.8-20.2) versus 9.8% (95% Cl 9.6-11.0) for neonatal death and 29.6% (96% CI 28.5-30.6) versus 17.5% (95% CI 15.7-18.3) for very preterm births, respectively).

CONCLUSIONS

Wide variations in MBR and their impact on population outcomes imply that efforts by countries to reduce MBR could improve perinatal outcomes, enabling better long-term child health.

Impact of Conception Method on Twin Pregnancy Course and Outcome

Objective: The aim of the study was to investigate the course and outcomes of twin pregnancies conceived by different methods of assisted reproduction (ART) compared to those conceived spontaneously. Methods: The study involved patients with twin pregnancies who delivered at the Ob/Gyn Clinic of the Clinical Center of Serbia over a period of three years. Patients were differentiated according to method of conception and type of ART. Age, parity, etiology of infertility, pregnancy complications, time of membrane rupture and type of delivery was recorded for each patient. Gestational week at delivery, presentation, birth weight, Apgar score, chorionicity and accompanying disorders were separately recorded for each twin. The data were analyzed statistically. Results: A total of 431 patients were included in the study. Although more twins were conceived by ART, the difference was not statistically significant (p = 0.092). The most common ART procedure was IVF/ICSI (p = 0.001). ART procedures, particularly IVF/ICSI, were significantly correlated with more advanced maternal age, fewer previous pregnancies and delivery by cesarean sections, usually planned (p = 0.001). Preterm membrane rupture was more common after ICSI, but preterm delivery and pregnancy complications were infrequent, irrespective of the method of conception (p = 0.001). ART twins were mostly dichorionic (p = 0.036). Monochorionic twins were conceived either spontaneously or with ICSI. Conception by ART was not correlated with twins' outcome (weight, Apgar score, disorders). Conclusions: ART procedures do not have a negative impact on twin pregnancy course and outcome. Twin pregnancies conceived spontaneously or by ART have similar outcomes.

Prevalence and risk of Down syndrome in monozygotic and dizygotic multiple pregnancies in Europe: implications for prenatal screening

OBJECTIVE

To determine risk of Down syndrome (DS) in multiple relative to singleton pregnancies, and compare prenatal diagnosis rates and pregnancy outcome.

DESIGN

Population-based prevalence study based on EUROCAT congenital anomaly registries.

SETTING

Eight European countries.

POPULATION

14.8 million births 1990-2009; 2.89% multiple births.

METHODS

DS cases included livebirths, fetal deaths from 20 weeks, and terminations of pregnancy for fetal anomaly (TOPFA). Zygosity is inferred from like/unlike sex for birth denominators, and from concordance for DS cases.

MAIN OUTCOME MEASURES

Relative risk (RR) of DS per fetus/baby from multiple versus singleton pregnancies and per pregnancy in monozygotic/dizygotic versus singleton pregnancies. Proportion of prenatally diagnosed and pregnancy outcome.

STATISTICAL ANALYSIS

Poisson and logistic regression stratified for maternal age, country and time.

RESULTS

Overall, the adjusted (adj) RR of DS for fetus/babies from multiple versus singleton pregnancies was 0.58 (95% CI 0.53-0.62), similar for all maternal ages except for mothers over 44, for whom it was considerably lower. In 8.7% of twin pairs affected by DS, both co-twins were diagnosed with the condition. The adjRR of DS for monozygotic versus singleton pregnancies was 0.34 (95% CI 0.25-0.44) and for dizygotic versus singleton pregnancies 1.34 (95% CI 1.23-1.46). DS fetuses from multiple births were less likely to be prenatally diagnosed than singletons (adjOR 0.62 [95% CI 0.50-0.78]) and following diagnosis less likely to be TOPFA (adjOR 0.40 [95% CI 0.27-0.59]).

CONCLUSIONS

The risk of DS per fetus/baby is lower in multiple than singleton pregnancies. These estimates can be used for genetic counselling and prenatal screening.

Effect of advanced maternal age on perinatal outcomes in twins: the impact of chorionicity

PURPOSE

In contrast to singletons, twins born to older mothers have lower rates of perinatal mortality than twins born to younger mothers. We examined whether differences in chorionicity could explain this unexpected maternal age effect.

METHODS

We used population-based data on twins born to mothers aged 20-29 (n = 3702) and ≥35 years (n = 1880) in the North of England, UK, 1998-2007. We calculated rate ratios (RR) and 95% confidence intervals (CIs) to estimate the effect of maternal age; adjusted RRs (ARRs) were estimated by the use of generalized estimating equations for Poisson regression controlling for chorionicity and other confounders.

RESULTS

Older mothers had a lower proportion of monochorionic twins (17.6% vs. 24.3%, P < .01); lower neonatal (RR, 0.57; 95% CI, 0.34-0.95) and perinatal mortality (RR, 0.74; 95% CI, 0.53-1.04). Adjustment for chorionicity attenuated these associations (ARR, 0.59; 95% CI, 0.35-0.98 and ARR, 0.80; 95% CI, 0.57-1.12, respectively) and after further adjustment for additional factors, both associations became nonsignificant. Older mothers had greater rates of small-for-gestational-age infants (ARR, 1.59; 95% CI, 1.24-2.05), and cesarean delivery (ARR, 1.31; 95% CI, 1.16-1.48).

CONCLUSIONS

Perinatal death rates were lower but not statistically different for twins born to older versus younger mothers. This association was attenuated by adjustment for chorionicity.

The effect of IVF pregnancies on mortality and morbidity in tertiary unit

BACKGROUND

There are several studies that have shown an increased risk of premature birth and developmental abnormalities with in vitro fertilization (IVF); however, the data on preterm mortality and morbidity are limited.

AIM

Our aim is to investigate whether IVF had an effect on the mortality and morbidity in neonates admitted to the neonatal intensive care unit.

METHODS

A total of 940 term and preterm babies who were admitted to the intensive care unit over a period of 2 years were enrolled. Of these, 121 babies were born after IVF and 810 were born after a natural conception and 9 were born after ovulation induction. Of these, 112 preterm babies were born after IVF and 405 preterm babies were born after a natural conception.

RESULTS

In the IVF group, the gestational age and birth weight were significantly lower than in the non-IVF group. Additionally, in the IVF group, multiple births were significantly higher than in the non-IVF group. IVF pregnancies increase preterm delivery but did not increase preterm mortality, and preterm morbidity did not differ among groups, except for intraventricular hemorrhage (IVH). Gestational age was shown to be the primary risk factor for IVH using a logistic regression analysis. Also when newborns at gestational age <32 weeks were compared using regression analysis, gestational age was the major risk factor for IVH.

CONCLUSION

IVF appears to be associated with premature delivery and the known risks associated with prematurity.

Does antenatal ultrasound labeling predict birth order in twin pregnancies?

OBJECTIVE

It is often assumed by obstetricians, neonatologists and parents that the prenatal nomenclature used to identify twins on ultrasound is consistent with twin labeling after their birth. The aim of this study was to use a large regional database of twin ultrasound scans to validate the effectiveness of a scan before delivery in predicting twin birth-order.

METHODS

A large regional database of twin ultrasound scans with data from nine hospitals over a 10-year period was used to identify all ultrasound examinations carried out just before birth. The discordance in twin order between the last scan and birth was evaluated by observing discrepancies in fetal sex and weight.

RESULTS

In total, 2103 twin pregnancies with ultrasound estimated fetal weights (EFWs) and birth weights were assessed. Of these, fetal sex was recorded in 149 different-sex pregnancies. Discrepancy between antenatal labeling and the anticipated birth order was noted in 37.6% (56/149) of cases when judged by sex discordance and in 36% (757/2103) of cases when judged by weight discordance. Multiple logistic regression analyses demonstrated that weight discordance, but not chorionicity, scan-to-delivery interval, gestation at scan or gestation at delivery, significantly influenced the change in birth order (P < 0.001).

CONCLUSION

Antenatal ultrasound labeling does not predict twin birth-order in a significant proportion of twin deliveries. This finding should be borne in mind not only by parents, but also by physicians when delivering twins discordant for anomalies that are not evident on external examination.

Trends in the prevalence, risk and pregnancy outcome of multiple births with congenital anomaly: a registry-based study in 14 European countries 1984-2007

OBJECTIVE

To assess the public health consequences of the rise in multiple births with respect to congenital anomalies.

DESIGN

Descriptive epidemiological analysis of data from population-based congenital anomaly registries.

SETTING

Fourteen European countries.

POPULATION

A total of 5.4 million births 1984-2007, of which 3% were multiple births.

METHODS

Cases of congenital anomaly included live births, fetal deaths from 20 weeks of gestation and terminations of pregnancy for fetal anomaly.

MAIN OUTCOME MEASURES

Prevalence rates per 10,000 births and relative risk of congenital anomaly in multiple versus singleton births (1984-2007); proportion prenatally diagnosed, proportion by pregnancy outcome (2000-07). Proportion of pairs where both co-twins were cases.

RESULTS

Prevalence of congenital anomalies from multiple births increased from 5.9 (1984-87) to 10.7 per 10,000 births (2004-07). Relative risk of nonchromosomal anomaly in multiple births was 1.35 (95% CI 1.31-1.39), increasing over time, and of chromosomal anomalies was 0.72 (95% CI 0.65-0.80), decreasing over time. In 11.4% of affected twin pairs both babies had congenital anomalies (2000-07). The prenatal diagnosis rate was similar for multiple and singleton pregnancies. Cases from multiple pregnancies were less likely to be terminations of pregnancy for fetal anomaly, odds ratio 0.41 (95% CI 0.35-0.48) and more likely to be stillbirths and neonatal deaths.

CONCLUSIONS

The increase in babies who are both from a multiple pregnancy and affected by a congenital anomaly has implications for prenatal and postnatal service provision. The contribution of assisted reproductive technologies to the increase in risk needs further research. The deficit of chromosomal anomalies among multiple births has relevance for prenatal risk counselling.

The North of England Survey of Twin and Multiple Pregnancy

The population-based Northern Survey of Twin and Multiple Pregnancy (NorSTAMP, formerly the Multiple Pregnancy Register) has collected data since 1998 on all multiple pregnancies in North of England (UK) from the earliest point of ascertainment in pregnancy. This paper updates recent developments to the NorSTAMP and presents some early mortality data from the first 10 years of data collection (1998-2007). Since 2005, mothers have been asked to give explicit consent for their identifiable data to be held by the survey, in line with changing guidance and legal frameworks for identifiable data. In 2009, regional standards of care for multiple pregnancies were developed, agreed, and disseminated. During 1998-2007, 4,865 twin maternities (pregnancies with at least one live birth or stillbirth) were registered, with an average twinning rate of 14.9 per 1,000 maternities. The overall stillbirth and neonatal mortality rates in twins were 18.0/1,000 births and 23.0/1,000 live births respectively. Stillbirth and neonatal mortality rates were significantly higher in monochorionic than dichorionic twins: 44.4 versus 12.2 per 1,000 births (relative risk [RR] 3.6, 95% Confidence Intervals [CI] 2.6-5.1), and 32.4 versus 21.4 per 1,000 live births (RR 1.5, 95% CI 1.04-2.2) respectively. There was no significant improvement during this period in either stillbirth or neonatal mortality rates in either chorionicity group. This population-based survey is an important source of data on multiple pregnancies, which allows monitoring of trends in multiple birth rates and pregnancy losses, providing essential information to support improvements in clinical care and for epidemiological research.