Multifetal reduction of triplets to twins improves perinatal outcome

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.

Multifetal pregnancy reduction of triplets to twins compared with non-reduced triplets: a meta-analysis

The current systematic review and meta-analysis evaluate the perinatal outcomes in twin pregnancies following multifetal pregnancy reduction (MPR) compared with non-reduced triplet pregnancies. All studies comparing perinatal outcome of twin pregnancies following MPR to non-reduced triplet pregnancies were considered. MEDLINE, non-indexed MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and Web of Science were searched for relevant published articles up to August 2016. The search yielded 653 publications of which 92 were assessed for eligibility. A total of 24 studies met the inclusion criteria. Overall, the outcomes of pregnancies following MPR were better compared with expectantly managed triplets. The MPR group delivered at a later gestational age and was less likely to be delivered before 32 or 28 weeks' gestation. Newborns in the MPR group had significantly higher birthweight at delivery (mean difference 500 g [95% CI 439.95, 560.04]). Rates of pregnancy loss before 24 weeks' gestation and overall infant survival were comparable between the groups. This meta-analysis suggests that MPR of triplet pregnancies to twins is associated with improved perinatal outcome compared with non-reduced triplets. Should primary prevention of high order multiple pregnancy fail, MPR is an appropriate alternative to minimize the perinatal morbidity and mortality of triplet pregnancies.

The paediatric consequences of Assisted Reproductive Technologies, with special emphasis on multiple pregnancies

Paediatricians will encounter many babies and children who are the result of assisted reproductive technologies. Although in most cases, there are no adverse health consequences, assisted reproductive technologies (ART) are associated with some risks that are reviewed in this article.

CONCLUSION

ART has had a major impact on multiple gestation and the incidence of prematurity in many countries. Among singletons, there are also increases in prematurity, small for gestational age, congenital anomalies and perinatal mortality.

Selective reduction in twins and multiple pregnancies

The number of multiple pregnancies has increased, mainly due to the uncontrolled use of the assisted conception techniques. Multifetal pregnancy reduction (MFPR) has been used to reduce the risks associated with these high-risk pregnancies. It is performed in the first trimester of pregnancy by transabdominal injection of potassium chloride into the fetal heart. The risk of miscarriage seems to be associated with the final number of fetuses. A review of the literature suggests that MFPR results in better pregnancy outcome, regardless of the initial number of fetuses. The reduction to a lower number of fetuses reduces fetal losses, prematurity, infant mortality and morbidity.

Risks of miscarriage and early preterm birth in trichorionic triplet pregnancies with embryo reduction versus expectant management: new data and systematic review

BACKGROUND

Triplet pregnancies are associated with a high risk of miscarriage and early preterm birth. It is uncertain if the outcome is improved by embryo reduction (ER).

METHODS

We examined trichorionic triplet pregnancies with three live fetuses at 10-14 weeks of gestation that were managed expectantly or by ER. The two groups were compared for the rates of miscarriage, defined as pregnancy loss before 24 weeks, and preterm delivery prior to 32 weeks. In addition, systematic searches were performed to identify studies comparing outcomes in expectant management versus ER in triplet pregnancies.

RESULTS

We combined data from 365 pregnancies managed in our centre with those of five previous studies. In total there were 893 pregnancies. In the ER group (n=482) compared to the expectantly managed group (n=411), the rate of miscarriage was higher [8.1 versus 4.4%; relative risk (RR)=1.83, 95% confidence interval (CI)=1.08-3.16, P=0.036] and the rate of early preterm delivery was lower (10.4 versus 26.7%, RR=0.37, 95% CI=0.27-0.51, P<0.0001). It was calculated that seven (95% CI=5-9) reductions needed to be performed to prevent one early preterm delivery, while the number of reductions that would cause one miscarriage was 26 (95% CI=14-193).

CONCLUSIONS

In trichorionic triplets, ER to twins is associated with an increase in the risk of subsequent miscarriage and decrease in risk of early preterm birth.

The relative myth of elective single embryo transfer

The option of single embryo transfer (SET) has recently dominated the pages of this and other medical journals. Opinions, in regards to the utility of such an approach, appear to differ between Europe and the US. While US guidelines promote a more individualized approach, European opinions, at times, even advocate mandated practice patterns. The European approach, however, fails to recognize the rather significant differences in supportive arguments between the historical switch from multiple embryo transfers to 2-embryo transfers and the current discussion, favouring a switch from 2-embryo transfer to elective (e)-SET. In the former, a significant risk of (at times, high-order) multiple pregnancies was reduced without loss of pregnancy potential. In the latter, a comparably relatively low twinning risk is reduced at the expense of declining pregnancy rates, a need for more treatment cycles, a potential delay in treatment success and, potentially, higher treatment costs. These consequences of e-SET, together with the preference of some infertility patients to actually conceive twins, raise serious questions about the wide utilization of e-SET, as has been propagated by many authorities. According to US guidelines, e-SET, therefore, appears to represent an appropriate transfer option for only a small minority of IVF patients. Argument in favour of indiscriminate SET appears unrealistic and should be reconsidered.

Cervical length, multifetal pregnancy reduction, and prediction of preterm birth

PURPOSE

To evaluate the application of transvaginal sonography assessment of cervical length before fetal reduction for predicting spontaneous preterm birth in triplet gestations reduced to twins.

METHODS

This retrospective study was conducted at the ultrasound unit of a university-affiliated municipal hospital. The study cohort consisted of 25 women with triplet gestations following ovulation induction or assisted-reproduction techniques who underwent fetal reduction to twins. Cervical length was assessed via transvaginal sonography before fetal reduction, and data on pregnancy outcome were retrieved from maternal records and/or maternal interviews.

RESULTS

Cervical length (mean +/- SD) at reduction was 4.0 +/- 0.85 (range: 1.2-5.5). Five women were excluded from statistical evaluation because pregnancy complications precluded spontaneous delivery. Two of 3 (67%) women with a cervical length of <3.5 cm delivered prior to 33 weeks' gestation compared with 1/17 (6%) women with a cervical length > or = 3.5 cm. This difference was statistically significant (P < 0.05). The sensitivity, specificity, positive predictive value, and negative predictive value of cervical lengths <3.5 cm to predict delivery prior to 33 gestational weeks was 67%, 94%, 67%, and 94%, respectively.

CONCLUSIONS

Measurement of cervical length in triplet pregnancies before fetal reduction provides useful predictive information on the risk for preterm delivery.

Embryonic Loss in Iatrogenic Multiples

Spontaneous reduction of multiple gestational sacs occurs less often in pregnancies conceived as a result of ovulation induction and assisted reproductive technology compared with spontaneously conceived multiple pregnancies. Whereas most spontaneous multiple pregnancies are twin gestations, a higher proportion of multiple pregnancies that result from ovulation induction and assisted reproductive technology are triplet and higher-order gestations. Recent evidence, described in this article, indicates that although twin and higher-order multiple gestations found on initial ultrasound subsequently may undergo spontaneous reduction to singletons or twins, there may be important consequences for the outcome of the surviving fetus or fetuses.

Multifetal pregnancy reduction and selective termination

MPR and ST are important options for patients who have multifetal pregnancies. Both procedures have been shown to be technically safe and result in acceptable pregnancy loss rates and GAs at delivery. An important caveat is that these findings are observed in centers that have vast experience performing this type of procedure and should not be generalized to all centers. The authors believe that the good outcomes reported here and elsewhere are a result of having a relatively limited number of operators adhering to a strict common protocol and that they should not be generalized to all centers. Awareness of the ethical and psychological issues aids counseling of patients and their follow-up, but more information is needed in this area. Finally, it is the authors' hope that advances in ART will decrease the need for MPR procedures in the future.

Triplet morbidity and mortality in a large case series

OBJECTIVE

A significant increase in the triplet birth rate has occurred recently. This rise is of concern, as these infants are historically reported to be at risk of adverse outcome. Thus, we examined the outcome of triplet births in a large contemporary case series.

STUDY DESIGN

Since 1993, detailed clinical data have been collected on all patients admitted to our Neonatal Intensive Care Unit. We retrospectively analyzed this database to examine triplet outcome.

RESULTS

A total of 51 consecutive sets of triplets were born over a 9-year period. The mean birth weight for triplets was 1789+/-505 g, mean gestational age was 32.6+/-2.7 weeks, with discordancy present in 17.6% of neonates. Complications of prematurity were infrequent. Triplet survival to discharge was 96%.

CONCLUSIONS

This large contemporary case series of triplets demonstrates excellent survival with low associated morbidity. These data suggest that there may no longer be medical justification for offering selective fetal reduction to parents with triplet pregnancies.

Invasive procedures in multiple gestations

PURPOSE OF REVIEW

The incidence of multiple gestations has increased significantly with advances in assisted reproductive techniques resulting in a concomitant increase in invasive procedures in these pregnancies. Commonly performed invasive procedures include amniocentesis, chorionic villus sampling, multifetal pregnancy reduction, and selective termination. Amniocentesis and chorionic villus sampling are also performed in singleton pregnancies, while multifetal pregnancy reduction and selective termination are procedures that are unique to multiple gestations.

RECENT FINDINGS

With increased operator experience, pregnancy loss rates after chorionic villus sampling, multifetal pregnancy reduction, and selective termination have decreased to acceptably low levels. Amniocentesis and chorionic villus sampling continue to have similar loss rates in experienced hands. A recent study suggests that amniocentesis in twins may have a higher post-procedural loss rate than in singletons; this may be due to the higher background loss rate of twins. There has been a recent increase in multifetal pregnancy reduction to a singleton with a trend towards improved outcomes over reduction to twins; future studies should focus on whether this confers a definitive advantage. Newer data suggests that selective termination after 20 weeks gestation in experienced hands does not increase loss rates over those procedures performed before 20 weeks. Newer techniques, such as cord coagulation, continue to be developed for selective termination in monochorionic pregnancies, though still with considerable morbidity and mortality.

SUMMARY

In summary, invasive procedures in multiple gestations are now commonly performed with. It is our hope that primary prevention of high order multiple pregnancies by optimization of assisted reproductive techniques will decrease the need for these procedures.

Spontaneous reduction of multiple pregnancy: incidence and effect on outcome

OBJECTIVE

Our objective was to determine the incidence of spontaneous reduction in multiple pregnancies during the first 12 gestational weeks and determine the outcome of the surviving fetuses.

STUDY DESIGN

Analysis of prospectively collected ultrasound and birth information on 709 multiple and 5962 singleton pregnancies conceived at a private infertility clinic.

RESULTS

Spontaneous reduction of one or more gestational sacs and or embryos occurred before the 12th week of gestation in 36% of twin (95% CI, 32%-40%), 53% of triplet (95% CI, 44%-61%), and 65% of quadruplet (95% CI, 46%-85%) pregnancies. Reduction was less frequent after ovulation induction than after spontaneous ovulation. In general, pregnancy duration and birth weight were inversely related to the initial gestational sac number irrespective of the final birth number.

CONCLUSIONS

More than 50% of patients with 3 or more gestational sacs had spontaneous reduction before 12 weeks. The surviving fetuses weighed less and were born earlier than unreduced pregnancies with the same initial number of fetuses.

Triplets: outcomes of expectant management versus multifetal reduction for 127 pregnancies

OBJECTIVE

Our purpose was to compare outcomes of women with triplet gestations conceived via assisted reproductive technology who chose expectant management or multifetal pregnancy reduction.

STUDY DESIGN

We performed a retrospective review of all women who initiated assisted reproductive technology cycles from August 1995 through July 1997 with ultrasonographic documentation of triplets exhibiting fetal heart tones at 9 weeks of gestation (N = 127). Patients were then uniformly referred to a maternal-fetal medicine specialist and to 3 centers offering multifetal pregnancy reduction.

RESULTS

Thirty-six percent of patients (46/127) chose multifetal pregnancy reduction with 95% undergoing reduction to twins. In the expectant management group, 13.6% of pregnancies were reduced spontaneously after 9 weeks of gestation. The "take home" infant per delivery rates for the multifetal pregnancy reduction and expectant management groups were 87% and 90.1%, respectively (P =.66). The mean gestational ages at delivery (+/-SE) for the multifetal pregnancy reduction and expectant management groups were 33.25 +/- 1. 03 weeks and 32.04 +/- 0.58 weeks (P =.23), and the mean birth weights of infants delivered at >24 weeks of gestation were 2226 +/- 79 and 1796 +/- 44, respectively (P <.0001). There were no significant differences in perinatal mortality, gestational age at delivery, or "take home" infant per delivery rates between these groups.

CONCLUSIONS

These data suggest that multifetal pregnancy reduction does not have a significant impact on the probability of live birth or on gestational age at delivery for women with triplets conceived with assisted reproductive technology.

Multifetal reduction of triplets to twins: a prospective comparison of pregnancy outcome

The aim of this study was to compare the outcome of triplets managed expectantly or by multifetal reduction to twins to assess the potential benefit of fetal reduction. The study design was prospective, comparative and monocentric and the study was conducted in a teaching hospital. Out of 148 women with triplets mostly obtained after infertility treatment, 83 were expectantly managed while 65 chose reduction to obtain twins. Main outcome measures were fetal loss before 24 weeks, premature deliveries before 28, 32 and 34 weeks, rate of low birthweight infants and neonatal and perinatal mortality rates. The fetal loss rate before 24 weeks did not differ between the ongoing group and the reduced group (6 versus 5.4%). Reducing triplets was associated with a significantly lower incidence of the following: prematurity before 28, 32 and 34 weeks (P < 0.001), low birthweight infants whose weights were under the third centile (P < 0.002) and infants whose weights were less than 1000, 1500 and 2000 g (P < 0.001). Neonatal (although apparently lower in the reduced group) and perinatal mortality did not significantly differ. Our results indicate that reduction of triplets to twins is effective to improve preterm birth and fetal growth.

Multifetal pregnancy reduction: perinatal and fiscal outcomes

OBJECTIVE

This study was undertaken to compare the birth outcomes of a multifetal pregnancy reduction population with those of other patients delivered at Hutzel Hospital, Detroit, and to determine the fiscal impact of the multifetal pregnancy reduction program.

STUDY DESIGN

In a retrospective review patients who were delivered after multifetal pregnancy reduction were compared with a general obstetric population who were delivered at Hutzel Hospital from January 1, 1986, through June 30, 1998. Outcome data were determined through a comprehensive perinatal database. The chi(2) analysis was used to examine the relationship between gestational age and delivery group. Financial data were estimated from published reports of neonatal intensive care unit admissions, cost estimates for neonatal intensive care unit care, and charges for multifetal pregnancy reduction.

RESULTS

Pregnancies reduced to triplets, twins, and singletons had outcomes at least comparable to unreduced pregnancies starting at these numbers and substantially better than unreduced pregnancies with the same starting number. Financial estimates of hospitalization costs averted in the multifetal pregnancy reduction population exceeded $28 million.

CONCLUSION

Use of multifetal pregnancy reduction improved obstetric outcomes for pregnancies with multiple gestations and also was associated with significant fiscal savings.

Maternal neonatal outcome in quadruplet and quintuplet versus triplet gestations

OBJECTIVE

Examination and comparison of the natural histories of triplet versus quadruplet and quintuplet gestations.

STUDY DESIGN

A retrospective study of sixty-four multifetal pregnancies (fifty-two sets of triplets, nine sets of quadruplets and three sets of quintuplets) cared for during past 12 years in our department. Quintuplets and quadruplets were compared with triplet pregnancies according to gestational age, birthweight, pregnancy complications and perinatal outcome. Student's t-test, Fisher exact test and chi2 test were used for statistical analysis, considering P value of <0.05 as statistically significant.

RESULTS

Although mean gestational age at delivery between triplets and higher order gestations was not significantly different, birthweight of quadruplets and quintuplets was significantly lower. Pregnancy complications, including intrauterine growth retardation, were equally distributed between the groups. Early neonatal and perinatal mortality were significantly higher in quadruplets and quintuplets than in triplets. Surprisingly, survival of growth retarded fetuses was better than survival of their eutrophic counterparts. The spontaneous loss rate was 11.5% for entire triplet gestation and 16.7% for quadru- and quintuplet pregnancies.

CONCLUSIONS

As the spontaneous loss rate of triplets and higher order pregnancies observed in our study is quite similar to pregnancy loss rate caused by multifetal pregnancy reduction, conservative management of multifetal pregnancies in specialised tertiary centers seems to be a prudent solution.

Obstetric outcome and psychological follow-up of pregnancies after embryo reduction

The obstetric outcome and psychological follow-up of the parents after embryo reduction performed at Sahlgrenska University Hospital between 1993 and 1997 in 13 women treated for infertility is described. A comparison is made with non-reduced multiple pregnancies, both spontaneous and multiple pregnancies after assisted reproduction technology. Altogether 10 triplets, two quadruplets and one quintuplet pregnancy underwent embryo reduction. The surgical procedure was performed in gestation week 7-8 by transvaginal, ultrasound-guided aspiration of embryonic tissue. The psychological follow-up included personal interviews and psychological evaluations by a Psychological General Well-being Scale (PGWB) and Beck's Depression Inventory (BDI). In 11 cases reduction was performed to twin pregnancies. In two cases of triplets after in-vitro fertilization and transfer of two embryos, reduction was performed on the monozygotic, monochorionic twins. No complete miscarriages occurred. Ten women delivered twins and three women delivered singletons. The mean gestation length was 40.4 weeks for singletons and 35.9 weeks for twins. The mean birthweight was 3411 g for singletons and 2392 g for twins. No complications related to the reduction were detected in the children.The psychological follow-up showed that the psychological well-being of the parents was good. However, the events around the reduction were experienced as chaotic and emotionally disturbing. One woman regretted the reduction. All couples emphasized that avoidance of high order pregnancies should be of primary importance. In conclusion, embryo reduction appears to improve the perinatal outcome of multiple pregnancies obtained after assisted reproduction technology. It is important that the surgical procedure is performed at a centre with experience of this type of intervention, by a limited number of surgeons and in a regulated manner. Psychologically, however, the intervention is traumatic and psychological management is essential for good final outcome.

Multifetal pregnancy reductions of triplets to twins: comparison with nonreduced triplets and twins

OBJECTIVE

Multifetal pregnancy reduction has been shown to improve survival rates in high-order multifetal pregnancies (>/=4). There is, however, some controversy as to whether multifetal pregnancy reduction improves pregnancy outcomes of triplets reduced to twins. The purpose of this study was to evaluate this issue by comparing outcomes of triplet gestations undergoing reduction to twins with outcomes of nonreduced twin gestations and expectantly managed triplet gestations.

STUDY DESIGN

The study included 143 triplet pregnancies that underwent reduction to twins over a 10-year period at a single center. These were compared with 12 nonreduced triplet pregnancies from the Wayne State University Perinatal Database and with 2 groups of twin pregnancies: 605 from the Wayne State University Perinatal Database and 207 from the Quest Diagnostics Database.

RESULTS

The miscarriage rate for expectantly managed triplets was 25%, compared with 6.2% for triplets reduced to twins. This rate was similar to the rates for both groups of nonreduced twins: 5.8% (Quest) and 6.3% (Wayne State University). Severe prematurity occurred in 25% of nonreduced triplets compared with 4. 9% of twins after reduction. This rate was also similar to that of nonreduced twins: 7.7% (Quest) and 8.4% (Wayne State University). The mean gestational age at delivery for expectantly managed triplets (32.9 +/- 4.7 weeks) was significantly shorter than for triplets reduced to twins (35.6 +/- 3.1 weeks). By comparison, nonreduced twins had a mean gestational age at delivery of 35.8 +/- 3.9 weeks for Quest and 34.4 +/- 3.6 weeks for Wayne State University. Mean birth weights were significantly lower in expectantly managed triplets as compared with triplets undergoing reduction to twins (1636 +/- 645 g vs 2381 +/- 602 g, respectively). Nonreduced twins had a mean birth weight of 2254 +/- 653 g for Quest and 2123 +/- 634 g for Wayne State University. Pregnancy loss rates, mean length of gestation, and mean birth weight did not vary significantly between triplets who underwent reduction to twins and nonreduced twins.

CONCLUSIONS

Reduction of triplets to twins significantly reduces the risk for prematurity and low birth weight and may also be associated with a reduction in overall pregnancy loss. This suggests that multifetal pregnancy reduction of triplets to twins is a medically justifiable procedure not only from an actuarial viewpoint but also from the ethical perspective of supporting patients' autonomy and respect for patients' individual circumstances.

Selective reduction of multifetal pregnancies to twins improves outcome over nonreduced triplet gestations

OBJECTIVE

Our purpose was to evaluate effects of multifetal pregnancy reduction on pregnancy complications and birth weights of remaining twin fetuses compared with expectantly managed triplets and nonreduced twins.

STUDY DESIGN

Medical records of 54 triplet pregnancies, 59 twin pregnancies resulting from multifetal pregnancy reduction, and 88 sets of twins conceived with assisted reproductive techniques and delivered at New York Hospital after 24 weeks were retrospectively reviewed. Birth weights were corrected for gestational age at delivery by use of a formula derived from composite standardized growth curves. Statistical analysis was performed with chi(2) analysis and Student t test.

RESULTS

Twins remaining after reduction and nonreduced twins were less likely to have preeclampsia than were triplets (14% and 23% vs 30%) and to be delivered before 36 weeks (39% and 27% vs 72%). They had birth weights that were > 100 gm larger than those of triplets even when corrected for gestational age. Reduced twins were similar to nonreduced twins in all parameters studied.

CONCLUSIONS

Multifetal pregnancy reduction results in pregnancy complications, gestational age, and birth weights closer to those of nonreduced twins than to expectantly managed triplets.

The current status of multifetal pregnancy reduction

The number of women conceiving three or more fetuses has increased dramatically as a result of successful infertility therapy with ovulation-inducing agents and assisted reproductive technology. Higher-order multiple gestations have an increased risk of premature delivery and its attendant sequelae of increased neonatal mortality or irreversible morbidity. Multifetal pregnancy reduction is a procedure designed to decrease the increased propensity to deliver very prematurely in these patients by reducing the number of live fetuses they are carrying. The procedure has proved to be both safe and effective, and pregnancies reduced to twins proceed as if that were the number of fetuses originally conceived. Nevertheless, this invasive procedure does have the potential to result in loss of the entire pregnancy and causes considerable emotional distress for some couples who view it as their "least bad" alternative. The medical benefits of performing multifetal pregnancy reduction in women with four or more fetuses seem fairly well established, but this is less true for triplets. Serious attention should be paid to reducing the number of higher-order multiple pregnancies resulting from infertility therapy. In the meantime, when three or more fetuses have been conceived, multifetal pregnancy reduction offers a reasonable option to patients whose only choices in the past were either to accept the risk of delivering extremely prematurely or to terminate the entire pregnancy.

Multifetal pregnancy reduction: evaluation of fetal growth in the remaining twins

OBJECTIVE

Our purpose was to study fetal growth after reduction of high-order multiple gestations to twins.

STUDY DESIGN

Birth weight and gestational age data were collected for 236 triplet and greater multiple pregnancies reduced to twins (113 triplets, 89 quadruplets, and 34 quintuplets or above) and was compared with those of a control group of unreduced twins.

RESULTS

Rates of intrauterine growth restriction per pregnancy were significantly different between the nonreduced and all categories of reduced multifetal pregnancies. The incidence of intrauterine growth restriction was 19.4% in the nonreduced twins, 36.3% in pregnancies reduced from triplets, 41.6% in pregnancies reduced from quadruplets, and 50% from higher-order multiple gestations. There was a statistically significant trend toward increasing frequency of intrauterine growth restriction with increasing starting fetal number (p = 0.04). The increase in intrauterine growth restriction was primarily accounted for by twin pairs with only one growth-restricted newborn.

CONCLUSION

Multifetal pregnancy reduction does not reduce the incidence of intrauterine growth restriction in the remaining fetuses to that of nonreduced twins.

Multifetal pregnancy reduction and selective termination

The incidence of multifetal pregnancies has increased dramatically since the advent of assisted reproductive technologies. Preterm delivery accounts for most of the mortality associated with multifetal pregnancies. Multifetal pregnancy reduction is a safe and effective procedure designed to decrease the adverse outcomes associated with very preterm deliveries. The increased incidence of multifetal pregnancies combined with reliable techniques for prenatal diagnosis of genetic and structural fetal anomalies have led to an increase in the diagnosis of abnormal fetal conditions in parents carrying multiple gestations. The development of the procedure of selective termination has provided prospective couples the option of selective termination of the abnormal fetus and continuation of the pregnancy.

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

OBJECTIVE

To assess the incidence of spontaneous embryo reduction as well as the obstetric and neonatal outcome of triplet gestations after assisted reproductive techniques (ART).

METHODS

We analyzed the spontaneous outcome of 38 pregnancies in which three gestational sacs were identified with vaginal ultrasound between 21 and 28 days after ART. Weekly follow-up visits were scheduled during the first trimester until referral to a high-risk obstetrician. After delivery, each patient was interviewed individually and, if necessary, the obstetrician was contacted.

RESULTS

The triplets delivery rate was 47.4%, whereas 31.6% delivered twins, 18.4% delivered singletons, and only one patient miscarried all three cases (2.6%). Finding three fetal heart beats was associated with a triplet delivery rate of 69.2%, a twin incidence of 19.2%, and a singleton birth rate of 11.6%. Embryo resorptions were observed mainly during the first 7 weeks of gestation and did not occur beyond the 14th week. The mean gestational age at delivery and neonatal birth weight were significantly lower among triplets (32.8 weeks and 1,740 g versus 35.3 weeks and 2,352 g in twins and 39.1 weeks and 3,122 g for singletons). Triplets had a 100% prematurity and cesarean section rate compared with 67% and 75% in twins and 0% and 43% in singletons, respectively. Hospitalization at the Neonatal Intensive Care Unit was required in 83% of newborn triplets, 29% of twins, and 0% of singletons, with a mean stay of 34 and 21 days for triplets and twins, respectively. One stillbirth and no neonatal deaths were reported, with an overall perinatal mortality rate of 11.9 per 1,000.

CONCLUSIONS

Spontaneously, approximately 50% of triplet pregnancies will experience at least one embryo resorption. The ongoing triplets demand a complex and more expensive perinatal management, a strong argument to consider limiting the number of oocytes-embryos transferred in ART.