Effects of selective reduction in triplet gestation: a comparative study of 80 cases managed with or without this procedure

Perinatal outcomes of monochorionic diamniotic triplet pregnancies: a case series

Background

Triplet pregnancies are associated with higher fetal morbidity and mortality rates as well as life-threatening maternal complications. Monochorionic diamniotic (MCDA) triplet pregnancies are very rare compared to other types of triplet pregnancies.

Case presentation

We report three cases of MCDA triplet pregnancies between January 2012 and December 2017. Two of these MCDA triplet pregnancies received regular and intensive prenatal care, were diagnosed by ultrasonography during the first trimester or early second trimester, and had good perinatal outcomes. The case with irregular perinatal care had poor outcomes, and the MCDA triplet pregnancy was diagnosed intrapartum.

Conclusions

The possibility of continuing an MCDA triplet pregnancy should be recognized. Early diagnosis, regular antenatal care, close prenatal monitoring, and sufficient communication are recommended to obtain better perinatal outcomes in MCDA triplet pregnancies.

Variable outcome in quintuplets pregnancy based on obstetric care

The incidence of multiple pregnancies has increased dramatically over the last few years in developed countries, largely attributed to delayed childbearing and the increasing use of assisted reproduction technologies and ovulation inducing hormones. Relatively few countries have population-based statistics covering birth statistics. Of those that do, the numbers of quintuplet pregnancies rose sharply in the nineties while, at the same time, their delivery rates decreased greatly because of the use of fetal reduction. Fetal reduction is not possible or legal in some countries, Poland being one of them, and therefore obstetricians are faced with the challenges of quintuplet deliveries. Conservative treatment and management is difficult, and outcomes often vary greatly. Despite this, expert care provided at tertiary care centers can positively influence outcomes. The objective of this article is to present different care options and their consequences in two illustrative cases, as well as to establish a set of obstetric care and management goals that would allow prolongation of the gestation time. Quintuplet pregnancy is rare but poses relevant clinical problems to both the obstetrician and the neonatologist. It should be managed with close cooperation between all concerned. Due to the extreme and invariable risk of premature delivery associated with quintuplet pregnancies, we recommend early diagnosis, adequate prenatal care at one tertiary medical center, routine hospitalization and bed rest, repeated ante partum ultrasound surveillance with tests of fetal well-being, tocolytic therapy at first signs of the risk of premature labor, and specialized neonatology care after delivery.

Perinatal and Early Childhood Outcomes of Twins Versus Triplets

The purpose of this prospective cohort study of twins and triplets was to evaluate perinatal and early childhood outcomes through 18 months of age. The study population included 141 twin pregnancies (282 twin children) and 8 triplet pregnancies (24 triplet children) recruited between May, 1996 and June, 2001. Mothers of triplets versus twins were significantly more likely to have infertility treatments, to be overweight or obese before conception, to be admitted antenatally, and to deliver by cesarean section. Length of gestation for triplets was significantly shorter (–2.31 weeks, p < .0001), and more likely to be less than 35 weeks (Adjusted Odds Ratio [AOR] 9.38, 95% confidence interval [CI] 3.22–27.29). Average birthweight for triplets was significantly lighter (–495 grams, p < .0001), and more likely to be low birthweight (AOR 11.38, 95% CI 3.11–41.61). Triplets were also more likely to be admitted to neonatal intensive care (AOR 7.97, 95% CI 2.13–29.77), to require mechanical ventilation (AOR 5.67, 95% CI 2.05–15.65), to develop respiratory distress syndrome (AOR 12.50, 95% CI 3.89–40.20), or a major morbidity (retinopathy of prematurity, necrotizing enterocolitis, ventilator support, or grade III or IV intraventricular hemorrhage, AOR 5.67, 95% CI 2.05–15.65). Weight, length, and head circumference was significantly smaller at birth for triplets compared to twins, and these differences remained through 18 months of age, along with lower mental developmental scores at the oldest age. Compared to twins, triplets have greater neonatal morbidity, and through 18 months of age lower mental and motor scores, slower postnatal growth and more residual stunting, particularly of length and head circumference.

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.

Bias in reported neurodevelopmental outcomes among extremely low birth weight survivors

OBJECTIVES

The purpose of this study was to investigate possible bias in the evaluation of neurodevelopment and somatic growth at 18 to 22 months' postmenstrual age among extremely low birth weight (ELBW) survivors (401-1000 g at birth).

METHODS

Data from a cohort of 1483 ELBW infant survivors who were born January 1993 through December 1994 and cared for at centers in the Neonatal Research Network of the National Institute of Child Health and Human Development were examined retrospectively. Children who were compliant with an 18- to 22-month follow-up visit, who visited but were not measured, or who made no visit were compared regarding 4 outcomes: 1) Bayley Scales of Infant Development, 2nd edition, Mental Developmental Index (MDI) <70 and 2) Psychomotor Developmental Index (PDI) <70, 3) presence or absence of cerebral palsy, and 4) weight <10th percentile for age. Logistic regression models were used to predict likelihood of these outcomes for children with no follow-up evaluation, and predicted probability distributions were compared across the groups.

RESULTS

Compared with children who were lost to follow-up, those who were compliant with follow-up were more likely to have been 1 of a multiple birth, to have received postnatal glucocorticoids, and to have had chronic lung disease. These factors were significantly associated with MDI and PDI <70 in the compliant group. Chronic lung disease was associated with increased risk of cerebral palsy (CP). MDI and PDI scores <70 were found in 37% and 29% of children who were evaluated at follow-up, respectively. Prediction models revealed that 34% and 26% of infants in the no-visit group would have had MDI and PDI scores <70. Compliant children tended to have greater incidence of MDI <70 compared with those predicted in the no-visit group but not PDI <70. CP was identified in 17% of the compliant group and predicted for 18% of the no-visit group. Predicted probabilities of having CP were marginally higher among the no-visit infants compared with those who were compliant with follow-up. There were no statistically significant somatic growth differences among the compliant, visit but not measured, and no-visit groups.

CONCLUSION

ELBW infant survivors who weighed 401 to 1000 g at birth and who are compliant with follow-up evaluations may have worse Bayley Scales of Infant Development, 2nd edition, MDI scores than infants with no visit. Thus, follow-up studies based on infants who are compliant with follow-up care may lead to an overestimation of adverse outcomes in ELBW survivors.

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.

Clinical dilemma in triplet pregnancy: when is it appropriate to intervene for a jeopardized fetus?

OBJECTIVE

To determine gestational age-specific risks of intervening to "rescue" a compromised fetus in triplet pregnancies.

STUDY DESIGN

We analyzed retrospectively triplet pregnancies managed at New England Medical Center (July 1992-May 2000; n=97 pregnancies). For each week in gestation, we compared the chance of at least one of three infants developing complications of prematurity in Scenario A (delivery at that gestation to rescue the jeopardized fetus) with the chance of at least one of two infants from Scenario B (allowing the jeopardized fetus to die in utero to prolong pregnancy) developing that complication later in gestation.

RESULTS

We observed a decreased risk of at least one infant developing a specific complication in Scenario B than in Scenario A for all complications studied.

CONCLUSIONS

Comparison of triplet outcomes with the two surviving older newborns identifies important changes in risk between 25 and 32 weeks. These data enable physicians and parents to weigh acceptable risks with benefits.

Trichorionic triplet pregnancies at 10-14 weeks: outcome after embryo reduction compared to expectant management

OBJECTIVE

To compare the outcome of trichorionic triplet pregnancies managed expectantly with those reduced to twins or singletons.

METHODS

This was a retrospective study of trichorionic triplet pregnancies with three live fetuses at 10-14 (median 12) weeks' gestation referred to our unit for consideration of embryo reduction. Women were counselled as to the available options of either expectant management or embryo reduction. In those choosing reduction, a needle was inserted into the uterus transabdominally and potassium chloride was injected into the fetal heart. Using data derived from this study and from a review of studies reporting on survival and handicap by gestational age in singletons, the effects of embryo reduction on survival and handicap rates were estimated. Main outcome measures were miscarriage before 24 weeks of gestation, preterm delivery before 32 weeks, perinatal death and handicap rates.

RESULTS

In total, there were 280 trichorionic triplet pregnancies and 125 of these were managed expectantly, 133 were reduced to two fetuses and 22 were reduced to one fetus. The rates of miscarriage were 3.2% for those managed expectantly, 8.3% for those reduced to twins and 13.6% for those reduced to singletons. The rates of early preterm delivery in those pregnancies that did not miscarry were 23.1%, 9.8% and 5.3%, respectively. The percentages for pregnancies with at least one survivor were 95.2%, 91.0% and 81.8%, respectively, and the median gestation at delivery was 34 weeks for the non-reduced, 36 weeks for those reduced to twins and 38 weeks for those reduced to singletons. From the published series on early preterm delivery, it was estimated that survival increases from about 27% at 24 weeks to about 98% at 32 weeks, and handicap decreases from 28% at 24 weeks to less than 5% at 32 weeks. From these estimates and the data on triplet pregnancies, it was calculated that, in triplets reduced to twins, compared to those managed expectantly, the chance of survival is similar (90.3% compared to 93.3%), but the risk of handicap may be lower (0.6% compared to 1.5% per fetus).

CONCLUSIONS

In trichorionic triplet pregnancies, embryo reduction to twins does not improve the chance of survival but may reduce the rate of handicap. Reduction from triplets to singletons may reduce both the survival rate and the handicap rate among survivors.

Morbidity and mortality of preterm twins and higher-order multiple births

OBJECTIVE

To determine if preterm infants of higher-order multiple (HOM) gestations have a significantly worse outcome during hospital stay when compared with preterm twins.

STUDY DESIGN

Retrospective cohort analysis.

METHODS

Perinatal outcome variables including gestational age (GA), birthweight, prenatal steroid use, cesarean section delivery rate, Apgar scores, and growth retardation were analyzed for 106 preterm HOM births (triplets and quadruplets) versus 328 preterm twins admitted to a single tertiary level neonatal intensive care unit. A comparison of the mortality and major neonatal morbidities such as respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, and retinopathy of prematurity was made for these two groups. In addition, the duration of respiratory support including surfactant therapy, nasal continuous positive airway pressure, and mechanical ventilation, as well as the length of hospitalization, was analyzed.

RESULTS

There were no significant differences in major morbidities between the infants of HOM and twin births of similar GA. There was no statistically significant difference in mortality, but the data showed a trend for lesser mortality in HOM. There was a highly significant increase in antenatal steroid use as well as the use of cesarean section for delivery in the HOM when compared with twin gestations. The infants of HOM gestations were of significantly lower birthweight than the twins and had a longer hospitalization.

CONCLUSION

Although premature infants of HOM had lower birthweight and needed a longer hospital stay, their mortality and morbidity at hospital discharge were not worse than that for preterm twins.

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.

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.

Multifetal pregnancy reduction in cases of threatened abortion of triplets

OBJECTIVE

To investigate the course of pregnancy and fetal outcome after first-trimester multifetal pregnancy reduction (MFPR) in patients with triplet pregnancies and uterine bleeding.

DESIGN

Case series of patients with threatened triplet pregnancies considered for MFPR.

SETTING

Department of Obstetrics and Gynecology, Rabin Medical Center, Petah-Tiqva, Israel.

PATIENT(S)

Forty-two patients with triplet pregnancies and first-trimester uterine bleeding.

INTERVENTION(S)

At 10-15 weeks' gestation, MFPR with intracardiac injection of potassium chloride was performed. The procedures were performed 7-10 days after cessation of bleeding (9-13 weeks) or in the presence of minimal uterine bleeding (14-15 weeks). In patients with heavy uterine bleeding, MFPR was postponed.

MAIN OUTCOME MEASURE(S)

Early- and late-pregnancy complications related to the procedure, pregnancy outcome, and fetal survival.

RESULT(S)

Performance of MFPR at 14-15 weeks was associated with a higher abortion rate (38.5%), lower mean gestational age at delivery (30.6 weeks), and lower mean twin birth weight (1,376+/-218 g and 1,014+/-202 g) than was performance of MFPR at 10-13 weeks (18.8%, 33.2 weeks, and 1,720+/-245 g and 1,596+/-170 g, respectively). Abortion occurred in four of the five patients with moderate to heavy uterine bleeding who did not undergo MFPR; the fifth patient gave birth prematurely at 28 weeks, and two of the newborns died.

CONCLUSION(S)

Pregnancy outcome and fetal mortality and morbidity in triplet pregnancy after MFPR are directly correlated with duration and amount of first-trimester bleeding.

First trimester ultrasonography of multiple gestations: a review

The objective was to review current literature pertaining to first trimester ultrasonography of multiple gestations. To this goal, all manuscripts published in the English language regarding this topic were selected and reviewed in a MEDLINE search from 1966 through May 1998. Additional sources were identified through cross-referencing. Current widespread application of first trimester ultrasonography and especially transvaginal sonography has introduced a new dimension in both diagnostic and management aspects of multiple gestations. Application of first trimester ultrasonography in multiple gestations enables an earlier and more precise depiction of important anatomical details regarding fetal viability, chorionicity, pregnancy outcome, structural abnormalities, pathophysiology of developmental disorders (such as twin reverse arterial perfusion [TRAP] sequence), early sonographic signs associated with fetal aneuploidy (nuchal translucency and abnormal crown-rump length), and potential fetal growth discordancy. First trimester ultrasonography also assists in guiding operative procedures including: amniocentesis, chorionic villus sampling, and selective fetal reduction. Enhanced information obtained with high-resolution, first trimester transvaginal ultrasonography is rapidly becoming a standard for establishing critical information that will assist clinicians to stratify management of multiple gestations. Given the increasing incidence of multiple gestations because of various assisted reproductive technology modalities, it is important that obstetricians become aware of the potential advantages of first trimester ultrasonography in clinical management of multiple gestations.

Management and outcome of triplet pregnancy

The parameters involved in obstetrical follow-up of triplet pregnancies were evaluated in a retrospective study between 1975-1993 of the follow-up of 91 triplet pregnancies. During this long interval of time, many changes in management of triplets occurred. Considering these differences, two periods in the present study were compared: 1975-1986, which consists of a previously published retrospective analysis of 21 triplet pregnancies; and 1987-1993, during which the modalities of the 7-year follow-up described previously were applied to 70 triplet pregnancies. No improvement was observed between the two periods. Nineteen pregnancies were spontaneous. Thirty-seven allowed treatment with ovulation induction agents and 35 were due to in vitro Fertilization. Early diagnosis of multiple pregnancies allows installation measures for the prevention of prematurity. Management, initiated upon diagnosis, included home rest and a weekly follow-up at home by a midwife every week. Monthly consultations and ultrasounds were performed at the hospital. Hospitalization was not systematic but was done in cases of maternal complications. The mean term for the diagnosis of triplet pregnancy was 13.9 +/- 5.3 weeks. The mean gestational age was 33.4 weeks; 90% of the deliveries were by cesarean section. The mean weight of the neonates was 1716 g. The mean Apgar score at 1 and 5 m was 7.7 and 9.3, respectively. The perinatal mortality was 80 per 1000. The main neonatal complications resulted from prematurity. Authors compared rates of Hyaline Membrane Disease in infants of patients treated with corticosteroids and of patients who were not. Hyaline Membrane Disease occurred in 13% of the corticotherapy group and in 31% of the untreated group. The present study supports systematic corticotherapy between 28 and 34 weeks for triplet pregnancies.

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.

The incidence of multiple gestations after in vitro fertilization is dependent on the number of embryos transferred and maternal age

OBJECTIVE

To determine if the incidence of multiple gestations after IVF differs significantly depending on the number of embryos transferred and maternal age.

DESIGN

Retrospective analysis of IVF database.

SETTING

Tertiary care academic center.

PATIENTS

One thousand eight hundred sixty-seven patients undergoing IVF with up to four embryos transferred during 1986 through 1993.

MAIN OUTCOME MEASURES

The rate of singleton and multiple gestations > 20 weeks estimated gestational age (EGA).

RESULTS

The incidence of triplet gestations > 20 weeks EGA among patients < or = 34 years of age with three versus four embryos transferred was 0.3% (1/335) versus 2.4% (15/662), respectively. The incidence of twin gestations > 20 weeks EGA among patients < or = 34 years of age with two versus four embryos transferred was 1.3% (3/234) versus 7.4% (46/622), respectively. Also among patients < or = 34 years of age, the incidence of singleton gestations > 20 weeks EGA with two versus three embryos transferred was 12.8% (30/234) versus 15.8% (53/335); with two versus four embryos was 12.8% (30/234) versus 17.2% (107/622); and with three versus four embryos was 15.8% (53/335) versus 17.2% (107/622), respectively.

CONCLUSIONS

In women < or = 34 years of age undergoing IVF-ET, the transfer of four versus three and four versus two embryos significantly increased the incidence of triplet and twin gestations, respectively, without significantly improving the chance of singleton conception. This implies that a policy of transferring only three embryos should be considered in this age group (realizing that such a policy may merit modulation if pretransfer embryo selection is used.).

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.