A comparison of the outcomes between twin and reduced twin pregnancies produced through assisted reproduction

The clinical outcomes of selective and spontaneous fetal reduction of twins to a singleton pregnancy in the first trimester: a retrospective study of 10 years

BACKGROUND

Singleton pregnancy is encouraged to reduce pregnancy complications. In addition to single embryo transfer (SET), selective and spontaneous fetal reduction (SEFR and SPFR) can also achieve singleton pregnancies. After SEFR or SPFR, an inanimate fetus remains in the uterus. It is unclear whether the inanimate fetus would adversely affect another fetus or the mother. Previous studies have focused on the differences between pre- and post-reduction. However, studies focusing on the influence of SEFR and SPFR on the remaining fetal development and maintenance of pregnancy are rare.

METHODS

Materials from 5922 patients whose embryo transfer dates ranged from March 2011 to January 2021 were collected. Both the SEFR group (n = 390) and SPFR group (n = 865) had double embryos transferred (DET) and got twin pregnancies, but subsequent selective or spontaneous fetal reduction occurred. The SET group (n = 4667) had only one embryo transferred. All were singleton pregnancies on the 65th day after embryo transfer. Clinical outcomes, including pregnancy outcomes, pregnancy complications, and newborn outcomes, were compared among the three groups.

RESULTS

After adjusting for age, infertility duration, types of infertility, states of embryos, body mass index, and factors affecting SET or DET decisions, multivariate regression analysis revealed that SEFR increased the risk of miscarriage (OR 2.368, 95% CI 1.423-3.939) and preterm birth (OR 1.515, 95% CI 1.114-2.060), and reduced the gestational age (βeta -0.342, 95% CI -0.544- -0.140). SPFR increased the risk of gestational diabetes mellitus (GDM) (OR 1.657, 95% CI 1.215-2.261), preterm premature rupture of membranes (PPROM) (OR 1.649, 95% CI 1.057-2.574), and abnormal amniotic fluid volume (OR 1.687, 95% CI 1.075-2.648). Both SEFR and SPFR were associated with reduced live birth rate (OR 0.522, 95% CI 0.330-0.825; OR 0.671, 95% CI 0.459-0.981), newborn birth weight (βeta -177.412, 95% CI -235.115--119.709; βeta -42.165, 95% CI -83.104--1.226) as well as an increased risk of low-birth-weight newborns (OR 2.222, 95% CI 1.490-3.313; OR 1.510, 95% CI 1.092-2.087).

CONCLUSIONS

DET with subsequent fetal reduction was related to poor clinical outcomes. We recommend that DET with subsequent fetal reduction should only be considered as a rescue method for multiple pregnancy patients with potential complications, and SET is more advisable.

The vanishing twin: Diagnosis and implications

Vanishing twin syndrome (VTS), defined by first-trimester spontaneous loss of a twin, is a common phenomenon with a reported prevalence of 15-35% of twin pregnancies. The etiology of VTS is obscure. Still, several risk factors have been identified, including an increased number of embryos transferred in pregnancies conceived by in vitro fertilization, an initial increased number of gestational sacs and advanced maternal age. The effect of VTS on obstetric and perinatal outcomes is controversial. Several studies have reported that pregnancies with VTS were associated with increased risk for preterm birth and small for gestational age neonates compared to singleton pregnancies, while others showed no difference in perinatal outcomes. The prevalence of placental vascular and anatomic abnormalities such as small placentas was higher in VTS. These findings lay an essential foundation for understanding how this phenomenon affects obstetric and perinatal outcomes of the surviving pregnancy.

Fetal Reduction Could Improve but Not Completely Reverse the Pregnancy Outcomes of Multiple Pregnancies: Experience From a Single Center

OBJECTIVE

To investigate the effectiveness and limitations of multifetal pregnancy reduction (MFPR) on the improvement of pregnancy outcomes of triplet or twin pregnancies conceived by in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI).

METHODS

We performed a cohort study of women undergoing IVF or ICSI from 2002-2016 in reproductive center, women's hospital, Zhejiang University School of Medicine. The cohort included 502 women who underwent MFPR and 9641 non-reduced women. Pregnancy outcomes were gestational age (GA) at delivery, pregnancy loss, preterm delivery, low birth weight (LBW), very low birth weight (VLBW), and small for gestational age (SGA). Multiple linear regression and logistic regression models were used to compare pregnancy outcomes between groups.

RESULTS

Triplets reduced to singletons had a longer median GA (39.07 vs 37.00, P<0.001), and lower rates of LBW (8.9% vs 53.2%, P<0.001) and SGA (17.8% vs 44.7%, P=0.001) than triplets reduced to twins, with a similar pregnancy loss rate (6.7% vs 6.6%, P=0.701). Twins reduced to singletons had a comparable pregnancy loss rate (4.8% vs. 6.5%, P=0.40), a longer median GA (38.79 vs. 37.00, P<0.001), and lower rates of LBW (13.5% vs. 47.0%, P<0.001) and SGA (13.5% vs. 39.6%, P<0.001) than primary twins. Triplets reduced to twins had higher rates of LBW (53.2% vs. 47.0%, P=0.028) and SGA (44.7% vs. 39.6%, P=0.040) than primary twins, with a similar pregnancy loss rate (6.6% vs. 6.5%, P=0.877). Singletons reduced from triplets/twins had higher rates of preterm delivery (15.8% vs. 7.3%, P<0.001), LBW (12.3% vs. 4.32%, P<0.001), VLBW (2.3% vs. 0.4%, P=0.002), and SGA (14.6% vs.6.6%, P<0.001) than primary singletons, with a comparable pregnancy loss rate (5.3% vs. 5.4%, P=0.671).

CONCLUSIONS

This study suggests that the pregnancy loss rate is similar between reduction and non-reduction groups. MFPR improves pregnancy outcomes, including the risk of preterm delivery, LBW, and SGA, but still could not completely reverse the adverse pregnancy outcomes of multiple pregnancies.

[Delivery of twin pregnancy and materno-fetal prognosis in a level 3 Tunisian University Center: a retrospective study about 399 cases]

En dépit des progrès obstétricaux et pédiatriques, les grossesses gémellaires représentent une situation à haut risque aussi bien pour le déroulement de la grossesse que pour l´accouchement et reste encore une situation angoissante pour l´équipe obstétricale. Le but de cette étude était de décrire la pratique des accouchements des grossesses gémellaires au service de gynécologie obstétrique de Sousse, de décrire le pronostic maternel et fœtal et d´analyser les facteurs pouvant l´influencer. Nous avons réalisé une étude descriptive, rétrospective portant sur les accouchements des grossesses gémellaires sur une période de deux ans. Ont été incluses dans l´étude les grossesses gémellaires ayant atteint au moins 28 semaines d´aménorrhée (SA) et les femmes ayants une grossesse gémellaire compliquée d'une mort fœtale in utéro. Ont été exclues les femmes ayant une grossesse gémellaire et ayant accouchés avant 28 SA. Les grossesses bi-choriales bi-amniotiques représentaient 67% des cas, contre seulement 11,5% de grossesses mono-choriales bi-amniotiques et 3% de grossesses mono-choriale mono-amniotique. Nous avons recensé 52 césariennes programmées. Le travail a été spontané dans 304 cas. Il a été déclenché dans 43 cas. Au total 178 parturientes ont accouché par voie basse (44,6%), contre 215 par voie haute (53,9%). Le taux de césarienne pour le deuxième jumeau était de 1,5%. Quand l'accouchement était par voie basse, 19 cas de complications ont été observés (10,7%). Nous avons analysé le score d'Apgar du premier jumeau et du deuxième jumeau en fonction du mode d'accouchement. Il n'y a pas eu de différence statistiquement significative du score d'Apgar entre les deux voies d'accouchement. La morbi-mortalité périnatale est plus importante pour le deuxième jumeau que pour le premier jumeau. La morbidité maternelle en cas d´accouchement par voie basse était supérieur à la morbidité en cas d´accouchement par césarienne. Il n´y a pas de différences significatives dans le score d´Apgar selon que les enfants sont nés par voie basse ou par césarienne.

Obstetrical outcomes of embryo reduction and fetal reduction compared to non-reduced twin pregnancies

PURPOSE

To prevent perinatal morbidity and mortality of high-order multiple pregnancy (HOMP), multifetal pregnancy reduction (MPR) is offered to some patients. In this study, we investigated whether twin pregnancies derived from MPRs carry a higher adverse obstetrical outcome compared to non-reduced control group of twins.

METHODS

We retrospectively analyzed the data from HOMPs on which transvaginal ER (n = 153) at a mean gestational age of 7.6 weeks or transabdominal FR (n = 59) at a mean gestational age of 12.4 weeks was performed between December 2006 and January 2018. The risk of each procedure was evaluated by comparing obstetrical outcome with that of a control population of 157 non-reduced twins conceived by infertility treatment.

RESULTS

The mean gestational ages at delivery were 35.2 weeks in the ER group, 35.7 weeks in the FR group, and 34.1 weeks in the control group (P = NS). Compared with those in the control group, the ER group had higher miscarriage (1.3% vs. 6.5%; P = 0.047; OR 0.21; 95% CI 0.45-0.898) and higher overall fetal loss (3.8% vs. 14.4%; P = 0.003; OR 0.24; 95% CI 0.09-0.60) rates. Differently compared with those in the control group, the FR group had no statistical difference in miscarriage (2.5% vs. 1.7%; P=NS) and overall fetal loss (3.8% vs. 6.8%; P=NS) rates.

CONCLUSIONS

Compared with the control group, ER in twins had a higher miscarriage and fetal loss rate, whereas FR in twins was similar to the control group. So, the FR procedure is overall a better and safer approach of MPR in reducing morbidity and mortality in HOMPs.

Perinatal Outcome in Assisted Reproductive Pregnancies: Comparative Analysis of Reduced versus Unreduced Gestation

Objectives. This study aims to evaluate perinatal outcomes such as gestational age at delivery and live birth rate in singleton and twin gestation with or without fetal reduction. Method. A retrospective analysis was done on patients which were divided into reduced and unreduced groups on the basis of order of reduction of one or more fetuses between 6 and 13 weeks of gestation. Patients records were studied to note gestational age at delivery/abortion, birth weight, and neonatal outcome. Result. The cohort included a total of 292 patients: 102 singletons and 190 twins. 52 pregnancies were reduced in singleton cohort and 68 were reduced in twin cohort. No statistical difference was observed in live birth rate, gestational age at delivery, and birth weight and significant higher incidence of IUGR was observed in reduced and unreduced twin gestation. In singleton pregnancies however preterm delivery rate increased with fetal reduction. Conclusion. Although reduction does not reduce the live birth rate, it does reduce gestation age of delivery and birth weight of newborn. This effect is more apparent when multiple gestation is reduced to singleton.

Obstetric outcomes in reduced and non-reduced twin pregnancies. A single hospital experience

Objectives:

To compare pregnancy outcomes between high-order multiple pregnancies resulting from assisted reproductive technology (ART) reduced to twins and non-reduced pregnancies, and to evaluate indications for using ART.

Methods:

This is a descriptive retrospective review of women with high-order multiple pregnancies reduced to twin carried out at the Department of Obstetrics & Gynecology, King Faisal Specialist Hospital & Research Center, Riyadh, Saudi Arabia between December 2010 and December 2013. The control group consisted of subjects with twin pregnancies who received their fertility treatment at the same hospital during the same period.

Results:

One hundred and twelve women were included in this study. Of women reaching fetal viability, significantly more women delivered before the thirtieth week in the study group (50% versus 12%, p<0.004). Miscarriage/delivery prior to fetal viability, chorioamnionitis, and preterm premature rupture of membranes were statistically higher in the study group. A total of 83% of the miscarriages in the study group were in women carrying 4 or more fetuses initially, and 50% of women in the study group were multiparous with no clear indication for fertility treatment.

Conclusion:

Although fetal reduction is a safe procedure, it is associated with complications. Primary prevention of high-order multiple pregnancy is recommended.

Use of the CryoPredict algorithm to predict live birth from cryopreserved embryos

BACKGROUND

Currently, the viability of cryostored blastocysts that are subsequently re-warmed is determined via the percentage of cell survival. However, the large number of cells that forms the blastocyst can make this estimate difficult and unreliable. Studies have shown that fast re-expanding blastocysts have superior pregnancy rates.

AIM

To determine whether the degree and speed of blastocoele re-expansion following cryopreservation and warming correlate with rates of live birth.

MATERIALS AND METHODS

A retrospective cohort study of 757 frozen embryo transfer cycles over a 4-year period at Royal Prince Alfred Hospital, Sydney. Clinical and embryology notes were retrieved. Details regarding patient demographics, stimulation cycle from which embryos were derived, frozen embryo transfer cycles, embryology and pregnancy outcomes were recorded.

RESULTS

Female (P = 0.01) and male age (P = 0.02) at the time of embryo creation were inversely associated with live birth. Fertilisation method (P = 0.03), embryo type at cryopreservation (P = 0.009), embryo grade at cryopreservation (P < 0.0001), percentage of cell survival post-thaw (P < 0.0001) and the degree of re-expansion (P = 0.003) were the IVF and embryology factors significantly associated with live birth. A predictive model (CryoPredict) was created in order to individualise the probability that the transfer of a given embryo would result in live birth.

CONCLUSIONS

The degree and speed of blastocoele re-expansion postcryopreservation and subsequent warming can be used in conjunction with other parameters to predict live birth.

Double trouble: should double embryo transfer be banned?

What role should legislation or policy play in avoiding the complications of in-vitro fertilization? In this article, we focus on single versus double embryo transfer, and assess three arguments in favour of mandatory single embryo transfer: risks to the mother, risks to resultant children, and costs to society. We highlight significant ethical concerns about each of these. Reproductive autonomy and non-paternalism are strong enough to outweigh the health concerns for the woman. Complications due to non-identity cast doubt on the extent to which children are harmed. Twinning may offer an overall benefit rather than burden to society. Finally, including the future health costs for children (not yet born) in reproductive policy is inconsistent with other decisions. We conclude that mandatory single embryo transfer is not justified and that a number of countries should reconsider their current embryo transfer policy.

Low birth weight: is it related to assisted reproductive technology or underlying infertility?

Since 1978, we have witnessed a successful evolution of assisted reproductive technology (ART), with improvement of the pregnancy rates and a growing demand. However, in recent years, there has been increasing concern regarding its safety due to the potential health impact on its infants. The raise of the developmental origins of adult disease has positioned low birth weight (LBW) as a significant health issue. Although multiple studies have associated ART with LBW, the etiology of this association remains largely unknown. We review the potential association between different components of ART and infertility with LBW, while acknowledging the limitations of interpretation of the existing literature.

Trichorionic quadruplet delivered beyond 36 weeks of gestation: a case report and literature review

Following one year of secondary fertility, a couple conceived with a quadruplet after transfer of three embryos through IVF-ICSI. At 36 weeks and 2 days of gestation, the mother developed gestational induced hypertension and delivered the next day by caesarean section. Pathology confirmed the zygosity to be trichorionic quadramniotic and all four babies were discharged home with their mother on postoperative day 3. Herein, we describe a successfully managed high-risk pregnancy case. A review of the literature was conducted and to our knowledge no other cases with similar criteria ever reached such advanced gestational age.

Selective reduction and termination of multiple pregnancies

The substantial increase in high order multiple pregnancies in the last two decades as a result of assisted reproductive techniques has necessitated the development of multifetal pregnancy reduction as a management tool to decrease fetal number and improve perinatal survival. The evidence in favour of reduction in pregnancies with more than four fetuses to twins is undisputed. Despite the recent improvements in expectant management of triplets with reasonable perinatal outcomes, the evidence suggests that reduction to twins significantly reduces the risk of preterm delivery without an increase in miscarriage rates. Recent advances in vascular-occlusive techniques have allowed the possibility of selective termination in monochorionic pregnancies in the presence of discordant anomalies or indeed multifetal reduction in non-trichorionic triplets, with radiofrequency ablation and cord occlusion appearing to be the most successful. However, the techniques vary in complexity and complication rates, which increase with gestation. Hence the need to refer these pregnancies early to specialist centres.