Outcome of triplet pregnancies after assisted reproductive techniques: how frequent are the vanishing embryos?

Anencephaly in a triplet pregnancy: Unprecedented spontaneous reabsorption in-utero and subsequent normal delivery via c-section: A rare case report

Multiple pregnancies are infrequently encountered, with the incidence of spontaneous triplet pregnancies estimated at approximately 1 in 7000 pregnancies. Triplet gestations are recognized for their propensity to bring about a spectrum of pregnancy related complexities, encompassing fetal structural abnormalities, neurological anomalies, disturbances in amniotic fluid levels, preterm labor, and suboptimal neonatal outcomes. Anencephaly is a serious congenital defect where the brain and skull do not fully develop, often leading to a poor prognosis. It's a preventable neural tube defect (NTD) with timely intake of folic acid, is caused by the incomplete closure of the neural tube during fetal development, resulting in the absence of the cerebrum (responsible for thinking and coordination) and the front part of the brain (forebrain) in affected infants. While anencephaly in a triplet is scarcely reported, spontaneous reabsorption of an anencephalic fetus in utero is a rare and unexpected event, with no documented cases in triplet pregnancies until now. We report a case of anencephaly in a triplet pregnancy where the mother presented late during her third trimester, the reabsorption of the anencephalic fetus in utero is an unprecedented event, highlighting the unique nature of this triplet pregnancy.

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.

Prevalence of Gestational Diabetes in Triplet Pregnancies: A Retrospective Cohort Study and Meta-Analysis

Background: Over the last decades, there has been a substantial increase in the incidence of higher-order multiple gestations. Twin pregnancies are associated with an increased risk of gestational diabetes mellitus (GDM). The literature on GDM rates in triplet pregnancies is scarce. Methods: A retrospective cohort study was performed to assess the prevalence of GDM in women with a triplet pregnancy. GDM was defined through an abnormal oral glucose tolerance test (OGTT). A meta-analysis of GDM prevalence was also carried out. Results: A cohort of 60 women was included in the analysis. Of these, 19 (31.7%) were diagnosed with GDM. There were no differences in pregnancy outcomes between women with and without GDM. In the meta-analysis of 12 studies, which used a sound GDM definition, an estimated pooled prevalence of 12.4% (95% confidence interval: 6.9–19.1%) was found. In a leave-one-out sensitivity analysis, the estimated GDM prevalence ranged from 10.7% to 14.1%. Conclusion: The rate of GDM seems increased in women with triplets compared to singleton pregnancies. However, GDM did not impact short-term pregnancy outcomes.

Detection of triploid, molar, and vanishing twin pregnancies by a single-nucleotide polymorphism-based noninvasive prenatal test

OBJECTIVE

We sought to determine the ability of single-nucleotide polymorphism-based noninvasive prenatal testing (NIPT) to identify triploid, unrecognized twin, and vanishing twin pregnancies.

STUDY DESIGN

The study included 30,795 consecutive reported clinical cases received for NIPT for fetal whole-chromosome aneuploidies; known multiple gestations were excluded. Cell-free DNA was isolated from maternal blood samples, amplified via 19,488-plex polymerase chain reaction, and sequenced. Sequencing results were analyzed to determine fetal chromosome copy number and to identify the presence of additional fetal haplotypes.

RESULTS

Additional fetal haplotypes, indicative of fetal triploidy, vanishing twin, or undetected twin pregnancy, were identified in 130 (0.42%) cases. Clinical confirmation (karyotype for singleton pregnancies, ultrasound for multifetal pregnancies) was available for 58.5% (76/130) of cases. Of the 76 cases with confirmation, 42.1% were vanishing twin, 48.7% were viable twin, 5.3% were diandric triploids, and 3.9% were nontriploid pregnancies that lacked evidence of co-twin demise. One pregnancy had other indications suggesting triploidy but lacked karyotype confirmation. Of the 5 vanishing twin cases with a known date of demise, 100% of losses occurred in the first trimester; up to 8 weeks elapsed between loss and detection by NIPT.

CONCLUSION

This single-nucleotide polymorphism-based NIPT successfully identified vanished twin, previously unrecognized twin, and triploid pregnancies. As vanishing twins are more likely to be aneuploid, and undetected residual cell-free DNA could bias NIPT results, the ability of this method to identify additional fetal haplotypes is expected to result in fewer false-positive calls and prevent incorrect fetal sex calls.

Fetal reduction of triplet pregnancy: one or two?

OBJECTIVE

To review outcomes following reductions in trichorionic triplet pregnancies at our institution.

METHOD

Retrospective analysis of the outcome of trichorionic triamniotic triplets reduced to singletons (group I, n = 44) or twins (group II, n = 136) at 10 and 12 weeks of gestation.

RESULTS

Reduction to one or two was based on parent's preference, hence unrelated to any specific obstetrical or maternal issue. Early fetal loss rate (e.g. <24 weeks) was 9.1% in group I versus 5.1% in group II (p = 0.83). In group I, the take-home baby rate was 86.4% versus 91.9% in group II (p = 0.8). In group I, 17.5% of the women gave birth between 33 and 36(+6) weeks of gestation versus 40.6% in group II (p = 0.026). Delivery beyond 37 weeks was 72.5% in group I and 46.9% in group II (p = 0.01). Intrauterine growth restriction rate was 27.0% in group I versus 45.0% in group II (p = 0.049).

CONCLUSION

Reduction to one rather than two fetuses led to significantly higher term delivery rate without significant differences in fetal loss rate or take-home baby rate.

Outcome of early first-trimester pregnancies (< 6.1 weeks) with slow embryonic heart rate

OBJECTIVE

The purpose of this article is to assess prospectively the value of concordant versus discordant gestational age (GA) calculations in predicting subsequent embryonic demise in embryos with a slow heart rate, as determined on early first-trimester ultrasound.

SUBJECTS AND METHODS

Thirty-six consecutive singleton pregnancies with slow embryonic heart rate (< 100 beats/min) measured on a 5.0- to 6.1-week ultrasound were prospectively identified. Pregnancies were defined as "discordant" if there was more than 5 days' difference between GA determined by biometrics compared with GA determined by last menstrual period and were defined as "concordant" if there was less than 5 days' difference between the GA measurements.

RESULTS

Of the 36 embryos with heart rate less than 100 beats/min at 5.0-6.1 weeks' GA, 16 went on to demise and 20 survived. Of the 16 that went on to demise, 14 were discordant (88%) and two were concordant (12%). Of the 20 that survived, 16 were concordant (80%) and four were discordant (20%). The proportion of discordant pregnancies that went on to demise was 14 of 18 (negative predictive value, 78%). The proportion of concordant pregnancies that went on to survival was 16 of 18 (positive predictive value, 89%). The rate of demise in the discordant group was significantly higher than that in the concordant group (p < 0.001, Fisher's exact test).

CONCLUSION

Embryonic heart rate less than 100 beats/min detected at 6.1 weeks or less is not necessarily a poor prognostic indicator. The likelihood of subsequent first-trimester survival is significantly higher if there is concordance between GA as calculated by biometrics and last menstrual period than if there is discordance.

Twin growth discrepancy in early pregnancy

OBJECTIVES

To assess whether early fetal growth restriction in a twin, expressed as the intertwin discrepancy in crown-rump length (CRL) between two viable twins at 7 + 0 to 9 + 6 weeks' gestation, is predictive of subsequent single fetal loss.

METHODS

This was a retrospective analysis of data collected prospectively over 3 years. Women attending an early pregnancy unit underwent a transvaginal ultrasound examination. In women with a viable twin pregnancy between 7 + 0 and 9 + 6 weeks of gestation, the CRL ratio between the two embryos was calculated. Women were followed up and the intertwin discrepancy in CRL at the 7 + 0 to 9 + 6-week scan was compared between cases in which there was spontaneous reduction to a singleton and those in which both twins remained viable at the 11-14-week scan.

RESULTS

There were 77 women included in the study and nine (12%) of these had a single fetal loss. Pregnancies with subsequent single fetal loss were more likely to have a larger median CRL discrepancy (42.0%; interquartile range (IQR), 23.8-64.3%) than were those which retained two viable fetuses (6.1%; IQR, 2.2-12.5%) (P < 0.0001). The median CRL discrepancy in subsequently viable monochorionic diamniotic twins (10.9%; IQR, 1.9-17.5%) was no different from that in dichorionic diamniotic twin pregnancies (5.9%; IQR, 2.1-12.3%) (P = 0.305). Regardless of chorionicity, there was a relationship between increasing CRL discrepancy and single fetal loss; the likelihood of a subsequently viable twin pregnancy was 97% if the discrepancy was < 20%, while if the discrepancy was > 60% there were no cases of both twins remaining viable (P < 0.0001). Receiver-operating characteristics curve analysis of CRL discrepancy in predicting single fetal loss gave an area under the curve of 0.93, with an optimum cut-off point of 16.9% discrepancy (sensitivity, 88.9%; 95% CI, 51.8-99.7; and specificity, 86.7%; 95% CI, 76.3-93.8).

CONCLUSION

There is a significant relationship between CRL discrepancy at 7 + 0 to 9 + 6 weeks and the likelihood of subsequent single intrauterine fetal loss. This suggests that spontaneous fetal demise of one twin may be preceded by growth restriction in the first trimester.

Spontaneous embryonic loss following in vitro fertilization: incidence and effect on outcomes

OBJECTIVES

The purpose of this study was to determine the early spontaneous loss rate in multiple pregnancies following assisted reproductive technology (ART).

STUDY DESIGN

Analysis of pregnancies following ART as related to the initial number of embryos and maternal age was performed.

RESULTS

At least one spontaneous loss was observed in 47.0% (95% CI 29.8-64.9) of quadruplets, 59.3% (95% CI 48.2-69.8) of triplets, and 35.2% (95% CI 29.6-41.2) of twins. The increased loss rates in mothers > or =35 years was related to early twin pregnancies, but not to early triplet and quadruplet gestations. We could not find an effect of the starting number of embryos on either gestational age or birth weight characteristics.

CONCLUSION

Our observations did not identify a clear relation between early spontaneous loss of multiple gestations and either initial number of embryos or maternal age. Other factors might be involved in the outcome of ART multiple pregnancies.

Multiple gestation as a marker of reproductive efficacy: learning from assisted reproductive technologies

This study postulates that apart from the number of embryos transferred, women with multiple gestation represent a subgroup of highly fertile individuals, whose embryos implant with higher efficiency than women with single gestation. Furthermore, each embryo generated from these women has a higher chance of reaching full term. The objective of this study was to compare implantation rate with the outcome of pregnancy (up to week 20) in multiple gestations following assisted reproductive techniques. The study group comprised 162 women with multiple gestation after assisted reproduction, followed prospectively with at least three ultrasound examinations performed between weeks 5 and 20 after the last menstrual period. Control group A comprised 344 fertile women with spontaneous single pregnancy followed with transvaginal ultrasound. Control group B consisted of 317 infertile women conceiving with single gestation after assisted reproduction and followed prospectively as in the study group. Embryo implantation rate and spontaneous embryo/fetal reduction, either partial or total (abortion), were registered in each case. Overall implantation in women with multiple gestation was higher (54.6%) than in the corresponding controls (25.6%). Furthermore, spontaneous embryo/fetus reduction was similar in the study cases and in fertile women (12.6 and 10.8% respectively) and significantly smaller than in the control group B (20.8%). Women with high reproductive efficacy exposed to assisted reproductive techniques generate cohorts of good quality embryos, with a high chance of implantation and of reaching birth.

Obstetric outcome after fetal reduction to singleton pregnancies

OBJECTIVE

To study the outcome after fetal reduction or selective termination to singleton pregnancies for various indications.

METHODS

Fetal reduction or selective feticide to singleton pregnancies was performed in 80 multiple gestations (congenital malformations, 17 cases; high-risk obstetric conditions, 25 cases; or social/psychological indications, 38 cases).

RESULTS

The overall pregnancy loss rate was 10%; however, pregnancy failure was significantly higher in selective reductions performed for preterm prelabor rupture of membranes (PPROM) (4/8) compared with monochorionic twin and bad obstetric history. Fetal reduction to singletons for psychological reasons resulted in a pregnancy wastage of 5.3% (2/38). Procedures performed at < or =14 weeks showed a significantly lower fetal loss rate (2/61; 3.3%), a higher mean gestational age at delivery (38.3+/-2.2 weeks), and a decreased prematurity rate (p< or =0.001). The number of reduced fetuses, prenatal diagnosis by chorionic villus sampling before the reduction and maternal age did not interfere with pregnancy outcome.

CONCLUSION

Fetal reduction to singleton pregnancies has a favorable outcome, especially when performed before 14 weeks of gestation.

Embryo fragmentation in vitro and its impact on treatment and pregnancy outcome

OBJECTIVE

To determine the impact of embryo fragmentation on pregnancy, obstetric, and perinatal outcome.

DESIGN

Retrospective analysis of embryo transfers that were homogeneous in regard to the degree of fragmentation.

SETTING

Fertility center.

PATIENT(S)

A cohort of 460 fresh embryo transfers.

INTERVENTION(S)

A total of 164 pregnancies were analyzed for the incidence of antepartum complications during gestation, obstetric (multiple pregnancy, preterm delivery, cesarean section), and perinatal outcome (sex, birth weight, admission to neonatal intensive care unit, malformations).

MAIN OUTCOME MEASURE(S)

Implantation and clinical pregnancy rate, obstetric and perinatal outcome.

RESULT(S)

Embryo fragmentation and number of embryos per transfer showed a significant influence on clinical pregnancy and implantation rate. No such relation was found concerning complications, multiple pregnancy rate, incidence of cesarean section, gestation week, birth weight, and average time at the neonatology. On the other hand, pregnancies derived from bad-quality embryos had a significantly higher rate of malformations.

CONCLUSION(S)

The higher percentage of malformations found in bad-quality embryos may be due to a higher percentage of apoptotic features and chromosomal disorders. For ethical reasons, the transfer of embryos with >50% fragmentation should be considered only after consultation with the patient.

Termination of pregnancy after conception with donor oocytes and donor spermatozoa: case report

Two couples, each suffering from longstanding primary subfertility due to severe oligoasthenoteratozoospermia in the male partner and perimenopause in the female, were referred to Bourn Hall Clinic for assisted conception treatment. Both couples received independent counselling prior to being accepted onto our programme. Both women conceived following embryo transfer. The embryos were created from (separate) donor oocytes and donor spermatozoa, and three and two embryos were transferred respectively. The first recipient conceived a triplet pregnancy, while the second conceived a twin pregnancy. Both felt unable to cope with their multiple pregnancies and declined further counselling. Both were offered elective fetal reduction; however, both declined and both decided to terminate their pregnancies. Both patients underwent termination of pregnancy, despite being advised against it. The reasons couples may opt for termination of their much-wanted pregnancies, after a protracted period of infertility, intensive and expensive infertility treatment and despite the counselling they receive before, during and after their treatment, are discussed.

Strategies to prevent multiple pregnancies in assisted conception programmes

All assisted conception techniques are associated with an increase in the multiple pregnancy rate. Iatrogenic multiple births are increasing as the use of these technologies expands. The cornerstone of safe ovulation induction is careful ultrasound monitoring, with cancellation of cycles if excessive ovulation is expected. In in vitro fertilization (IVF) cycles, the main determinant of multiple pregnancy risk is the number of embryos replaced. The current move in IVF clinics is to reduce the risk of multiple pregnancy by reducing the number of embryos transferred. We would suggest a maximum of two embryos transferred to women under, for example, 39 years of age. Women of 39 years or over have a reduced chance of embryo implantation; they should be allowed the transfer of up to three embryos (the UK legal maximum).

A triplet pregnancy after in vitro fertilization is a procedure-related complication that should be prevented by replacement of two embryos only

OBJECTIVE

To investigate whether the incidence and obstetric outcome of triplet pregnancies after IVF treatment justify strict limitation of the number of embryos to be replaced to two.

DESIGN

Retrospective analysis.

SETTING

A transport IVF program.

PATIENT(S)

All patients who had more than one embryo replaced.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Obstetric outcome, pregnancy.

RESULT(S)

High-order pregnancies occurred in 24 cases (23 triplets and 1 quadruplet). Three patients opted for selective embryo reduction (12.5%). Three triplet pregnancies spontaneously reduced to twins. Comparison of 18 triplets, reaching at least 20 weeks' gestation, with 54 twin pregnancies shows a higher perinatal mortality in the triplet group, causing 6 out of 18 patients to be confronted with at least one perinatal death. Triplets were born at a lower gestational age, had a lower birth weight, and a higher hospital admission rate of longer duration. Replacement of two, three, or four embryos did not lead to differences in pregnancy rates in the population studied. When a pregnancy occurred after replacement of three embryos, the risk of having a triplet pregnancy was 7.5%.

CONCLUSION(S)

The obstetric outcome of triplet pregnancies in our population indicates that triplet pregnancies after IVF treatment have to be prevented. Selective embryo reduction is acceptable for few patients only and can therefore not be seen as a solution. Replacement of three embryos results in triplet pregnancy in an unacceptably high percentage. Replacement of two embryos only gives acceptable IVF results and is the method chosen in the IVF program in Rotterdam to prevent triplet pregnancies.

Factors responsible for multiple pregnancies after ovarian stimulation and intrauterine insemination with gonadotropins

PURPOSE

The present study was undertaken in order to analyze possible factors that could be responsible for multiple pregnancies in normoovulatory women undergoing superovulation with gonadotropins and intrauterine artificial insemination.

METHODS

We retrospectively analyzed several clinical parameters in patients that achieved gestation with this treatment. Patients were divided into two groups depending on sperm origin (husband and donor sperm). Furthermore, they were subclassified as follows: (a) cycles resulting in single pregnancies (n = 366), (b) cycles ending in multiple pregnancies (n = 126), and (c) a control group composed of unsuccessful cycles (n = 366).

RESULTS

In cycles employing husband's sperm, the age, number of cycles necessary to reach pregnancy, serum estradiol (E2) levels, and number of follicles were significantly (P < 0.05) different in multiple pregnancies compared to single or nonpregnant cycles. In donor insemination, women with multiple pregnancies were significantly younger than nonpregnant patients. There was a significant increase in the number of follicles developed (P < 0.00001) and serum E2 levels on the day of hCG (P < 0.05) in multiple compared to single pregnancies and unsuccessful cycles. The number of motile sperm in the insemination specimen was not different among the established groups. When both types of treatments were grouped, pregnant patients were significantly (P < 0.00001) younger than women with failed cycles. In addition, multifetal pregnancies were significantly (P < 0.05) more frequent in women < 30 years old. E2 production was significantly (P < 0.00008) higher in twin and multifetal pregnancies than in single or nonpregnant cycles. Follicular development was also significantly (P < 0.00001) higher in twin and multifetal pregnancies compared to failed cycles.

CONCLUSIONS

The results suggest that young women (< 30 years) who develop more than six follicles with E2 > 1000 pg/ml when stimulated with gonadotropins are at higher risk of multiple gestation. These data may be helpful in preventing this undesired complication of assisted reproduction techniques.