Monochorionic high-order multiple pregnancies and multifetal pregnancy reduction

OBJECTIVE: To study the frequency and obstetric outcome of monochorionic multiple pregnancies in a population referred for fetal reduction. METHODS: Data charts of all patients with multifetal (> or =3) pregnancies referred for fetal reduction over the last 10 years were reviewed for the presence of monochorionic twin pairs or triplets. RESULTS: Twenty-nine of 239 high-order multiple pregnancies contained a monochorionic component (12.1%), eight of which were monochorionic triplets. Half of all naturally conceived pregnancies contained a monochorionic component. High-order multiple pregnancies with a monochorionic component resulted significantly more frequently from natural conceptions (7 of 29) than multichorionic pregnancies (7 of 210) (P =.001). Fetal reduction of the monochorionic twin pair in 21 pregnancies resulted in eight twin and 13 singleton pregnancies; mean gestational age at delivery was, respectively, 34.3 +/- 2.9 and 39.2 +/- 1.4 weeks. Pregnancy loss rate was one of 21 (4.8%). In the remaining eight multiple pregnancies with a monochorionic triplet present, three were complicated by a twin reversed arterial perfusion sequence, and two couples requested a first trimester termination of pregnancy. Fetal reduction of the monochorionic triplet in a dichorionic quadruplet pregnancy resulted in a normal pregnancy outcome. In two monochorionic triplet pregnancies, fetal reduction to monochorionic twin pregnancies with bipolar coagulation of the umbilical cord resulted in a favorable pregnancy outcome. CONCLUSION: Monochorionic twins or triplets are frequently part of naturally conceived high-order multiple pregnancies. Reduction of the monochorionic twin pairs improves pregnancy outcome. Monochorionic triplet pregnancies show a high complication rate, but may benefit from fetal reduction by cord coagulation.     

Parto diferido del segundo gemelo

The incidence of multiple pregnancies has increased in the last few years. Patients with multiple pregnancies are at risk of preterm delivery associated with high perinatal mortality and morbidity. Delivery of the first twin in a multiple gestation is usually followed by delivery of the second twin shortly thereafter. A prolonged interval between delivery of the fetuses in a multiple pregnancy is infrequent. We report seven cases of multiple pregnancies with delayed-interval delivery of the second twin. On the basis of our experience and a review of the literature, we conclude that delayed delivery of the second twin in very preterm gestational ages, with careful observation of fetal and maternal status, is recommended to improve survival and decrease morbidity in the second twin.     

Prolonged Induction to Delivery Time in Termination of Pregnancy Using 16,16-dimethyl-PGErmethyl ester (gemeprost) for Fetuses with a Neural Tube Defect or Hydrocephalus

Summary: A retrospective study is reported comparing the induction to delivery interval using gemeprost for termination of pregnancy, in the second trimester, in 3 groups of patients. It was observed that the mean induction to delivery interval was significantly longer in 75 pregnancies where there was a fetus with a neural tube defect and or hydrocephalus (31.7 hours) compared with 88 pregnancies with other fetal abnormalities (19.7 hours) and 84 pregnancies where there was an intrauterine death (113 hours). There was also an increase in the requirements for further intervention to obtain delivery in the group with a neural tube defect or hydrocephalus (n=33) compared with where there was an intrauterine fetal death (n=4) and other abnormality (n=14). We believe these results should be considered when counselling patients who have requested termination of pregnancy for fetal abnormalities.     

The prediction and prevention of intrapartum fetal asphyxia in preterm pregnancies

OBJECTIVE: This study was undertaken to examine the contribution of electronic fetal heart rate monitoring in the prediction and prevention of intrapartum fetal asphyxia in the preterm pregnancy. STUDY DESIGN: The outcome of 40 pregnancies with biochemically confirmed intrapartum fetal asphyxia (ie, an umbilical artery base deficit >12 mmol/L) was examined. This included 20 pregnancies that were delivered abdominally matched with 20 pregnancies that were delivered vaginally. Antepartum and intrapartum clinical risk factors and newborn complications were documented. The interpretation of the fetal heart rate record as determined by the responsible clinicians was recorded. Fetal asphyxia was classified as mild, moderate, or severe on the basis of an umbilical artery base deficit of >12 mmol/L and newborn encephalopathy and other organ system complications. RESULTS: Fetal asphyxia was classified as mild in 21 pregnancies and as moderate or severe in 19 pregnancies. The fetal heart rate record was predictive of fetal asphyxia in 27 pregnancies and nonpredictive in 11 pregnancies. The predictive fetal heart rate record was the primary indication for intervention in 21 of the 24 pregnancies that were delivered by cesarean delivery in the first stage or operative vaginal delivery in the second stage of labor. Newborn outcome may have been influenced by intervention and delivery because of a predictive fetal heart rate record in 10 pregnancies with mild fetal asphyxia and in 9 pregnancies with moderate or severe fetal asphyxia. CONCLUSION: Electronic fetal monitoring is a useful screening test for the prediction of intrapartum fetal asphyxia in the preterm pregnancy. A predictive fetal heart rate record was the principle indication that led to intervention and delivery. A prediction of fetal asphyxia that leads to intervention and delivery may prevent or modify moderate or severe newborn morbidity as the result of fetal asphyxia.     

Interstitial laser therapy for fetal reduction in monochorionic multiple pregnancy: loss rate and association with aplasia cutis congenita

OBJECTIVE: To evaluate experience with interstitial laser therapy for intrafetal vascular ablation in monochorionic (MC) multiple pregnancy. METHODS: MC pregnancies that underwent fetal reduction between 1998 and 2007 by interstitial laser therapy were reviewed. Indications were twin reversed arterial perfusion sequence (TRAP) (n = 10), twin-to-twin transfusion (6), discordant abnormality (7) or growth (1) and high-order multiples (6). RESULTS: Thirty pregnancies treated at 15 weeks (median, range: 11 weeks-20 weeks, 5 days) had no technical failures but four manifested procedure-related amniorrhexis. Four of 38 remaining fetuses suffered intrauterine death (IUFD) within 24 h, giving an early procedure-related fetal loss rate of 10% per pregnancy and 11% per fetus. A further five IUFDs occurred within 2 weeks, giving a maximum procedure-related loss rate of 27% per pregnancy and 24% per fetus. Median gestation at delivery was 37 weeks (18 weeks, 1 day-41 weeks, 3 days) for pregnancies continuing > 2 weeks. Perinatal survival was 26 of 38 (68%) in nonreduced fetuses. Two of 26 neonates (8%) were diagnosed with aplasia cutis congenita (ACC). CONCLUSION: Interstitial laser therapy in complicated MC pregnancies carries significant risks of unintended fetal loss and may be associated with ACC.     

Intrapartum management of multifetal pregnancies

Over the past several decades advances in assisted-reproductive technologies have resulted in a dramatic increase in the number of multifetal gestations. Concomitant with this increase there has been a gradual rise in the overall preterm birth rate, as well as other pregnancy complications related to these pregnancies. Twin, triplet, and other high-order multifetal gestation pregnancies pose a number of important issues related to antepartum and intrapartum management. Antepartum issues include ultrasound determination of zygosity, management and prevention of preterm labor, maternal/fetal surveillance for complications, and specific interventions focused on prevention of adverse maternal and/or fetal outcomes. Intrapartum issues include those related to timing of delivery, labor management, anesthesia options, and determination of an optimal delivery modality. Clearly, these issues related to the management of multifetal pregnancies are of paramount importance to optimize pregnancy outcome. As many of the issues related to antepartum care for women with multifetal gestations have been reviewed elsewhere, we have restricted the focus of this article to intrapartum management. Thus, this article reviews salient issues related to the intrapartum management of multifetal gestations, including twins, triplets, and other high-order pregnancies.     

Aggressive perinatal care for high-order multiple gestations: Does good perinatal outcome justify aggressive assisted reproductive techniques?

OBJECTIVE: The purpose of this study was to determine the factors that must be considered for appropriate counseling of patients with high-order multiple gestations.Study Design: A retrospective chart review was carried out from all high-order multiple gestations that were managed by a single perinatology group from February 1993-June 1998. Twin pregnancies that did not result from fetal reduction procedures were used as a control group. RESULTS: Clinical outcome data were analyzed from 9 quadruplet, 25 triplet, 19 reduced twin, and 24 nonreduced twin pregnancies. Women with quadruplet pregnancies were admitted more frequently at an early gestational age, the infants were delivered earlier, and the maternal and neonatal hospital days were longer than for triplet and reduced and nonreduced twin gestations. Triplet pregnancies had an earlier gestational age at delivery (32.3 vs 34.2 weeks), a higher incidence of preterm labor (87% vs 68%), and a higher percentage of neonatal intensive care unit admissions (94% vs 59%) than reduced twin gestations. Reduced twins were hospitalized longer (16.4 vs 9.8 days), were delivered earlier (34.2 vs 36.2 weeks), had a higher incidence of preterm labor (68% vs 29%), and had a greater percentage of neonatal intensive care unit admissions (59% vs 21%), a greater percentage of birth weight <1500 g, and a greater frequency of respiratory distress syndrome (16% vs 2%) than nonreduced twins. There was no difference in neonatal survival and neurologic morbidity when all groups were compared. CONCLUSION: Although early delivery and prolonged (maternal and neonatal) hospitalization were common with quadruplets and triplets, maternal and neonatal outcomes were excellent. The decision for reduction from triplets to twins may not necessarily change pregnancy outcome but should still be discussed as an option for the parents. Continued efforts need to be made to reduce the overall number of iatrogenic high-order multiple gestations.     

Delayed interval delivery in multiple pregnancies. Is optimism justified?

OBJECTIVE: Evaluation of the success of delayed interval delivery in multiple pregnancies. METHOD: Retrospective analyses of all multiple pregnancies with the birth of one child at a gestational age of 16-31 weeks (n=80). Three groups were defined: group I, unsuccessful attempt to temporize delivery, group II, interval between the first child and the other child or children 3 hours or more, with delivery of the remaining children before 28 weeks and group III, prolongation of pregnancy beyond 28 weeks. RESULTS: In 15 multiple pregnancies (ten sets of twins, five sets of triplets), the aim was to postpone the delivery of the second (and third) child. The mean gestational age at admittance was 25 weeks. Delay of the delivery of the second child was achieved in ten cases, five in group II and five in group III. In groups II and III, the mean interval of delivery was 12 days; the gestational age at the delivery of the remaining children in these ten patients was 27 5/7 weeks. No relation could be found between the reason for admittance and the interval in delivery between the first and the other children. The only severe maternal complication was blood loss exceeding 2 liters. In the neonatal outcome of first and second children (with a gestational age of 28 weeks or more) no striking differences were observed. CONCLUSION: Delayed delivery in multiple pregnancies after the birth of the first child is only successful in a minority of patients and should be considered prior to the birth of the first child.     

Betamethasone associated changes in umbilical artery flow velocity waveforms in multiple pregnancies with umbilical artery absent end diastolic flow

OBJECTIVES: It has been previously shown that glucocorticoids alter umbilical artery flow velocity waveforms in singleton pregnancies complicated by umbilical artery absent end diastolic flow. Whether similar effects are evident in multiple pregnancies where one fetus has umbilical artery absent end diastolic flow is not known. METHODS: Women with a twin or triplet pregnancy complicated by umbilical artery absent end diastolic flow in one fetus were admitted to hospital for intensive fetal surveillance including daily umbilical artery flow velocity waveform studies, as per hospital protocol. All women received prophylactic betamethasone (11.4 mg x 2, 24 h apart) in anticipation of preterm delivery. RESULTS: Between October 1996 and February 2002, 24 women with a multiple pregnancy complicated by umbilical artery absent end diastolic flow were cared for. Of these, six had a pregnancy with feto-fetal transfusion and excluded from further analysis. Of the remaining 18 women, eight had monochorionic diamniotic twins, eight had dichorionic twins, and two had trichorionic, triamniotic triplets. The median (range) gestation at diagnosis of umbilical artery absent end diastolic flow was 210.5 days (173-241). In nine (50%) of the 18 pregnancies the administration of betamethasone was associated with return of umbilical artery end diastolic flow for a median of 5 days. There was no association between this effect and chorionicity. The median (range) interval from diagnosis of umbilical artery absent end diastolic flow to delivery was 11 days (1-46). CONCLUSIONS: As previously reported in singleton pregnancies, the maternal administration of betamethasone in multiple pregnancies with umbilical artery absent end diastolic flow is associated with a transient return of end diastolic flow.     

Multiple pregnancies with gamete intrafallopian transfer (GIFT): Complications of a new technique

A complication related to the gamete intrafallopian transfer (GIFT) procedure involving a sextuplet pregnancy is described. Selective reduction of the fetuses to two, with normal delivery at term, was able to be performed. Problems with regard to multiple pregnancy with this procedure are discussed as well as ways to decrease the probability of this occurring.     

First-trimester fetal reduction to a singleton infant or twins: outcome in relation to the final number and karyotyping before reduction by transabdominal chorionic villus sampling

OBJECTIVE: The purpose of this study was to evaluate fetal outcome and maternal complications of multifetal pregnancy reduction to a single fetus or twins. To evaluate safety and efficacy of transabdominal chorionic villus sampling for karyotyping before fetal reduction. STUDY DESIGN: Four hundred twenty-four consecutive multiple pregnancies were reduced to twins (255 pregnancies) or a single fetus (169 pregnancies) at 8 to 13 weeks of gestation after transabdominal chorionic villus sampling for fetal karyotyping. Fetal and maternal outcome were observed prospectively and compared with control series of twin (147) and singleton (885) pregnancies in which reduction procedures were not performed. RESULTS: Transabdominal chorionic villus sampling was performed successfully in 100% of the cases. The accuracy of karyotyping was 99.2%. The overall pregnancy loss rate after reduction was 3.3%. No differences were observed between study and control series for severe prematurity, low birth weight, and neonatal deaths. Mean gestational age at delivery (35.2% vs 38.1%) and mean birth weight (2180 g vs 2873 g) were significantly lower; preterm delivery (64% vs 11%), neonatal death (3.4% vs 0.6%), and maternal complications (42.8% vs 9.5%) were significantly higher when the reduction was to twins rather than in reduction to a single fetus. Pregnancy loss rate did not differ between study series. The overall rate of chromosomal abnormalities in the study series was higher (relative risk, 2.0) than in singleton control series. CONCLUSION: The outcome of multiple pregnancies that were reduced to a single fetus or twins was similar to that of nonreduced pregnancies; fetal and maternal complications were significantly lower in the series of pregnancies that were reduced to a single fetus. The safety and efficacy of transabdominal chorionic villus sampling and the higher pregnancy rate of chromosomal abnormalities in multiple pregnancies imply that fetal karyotyping should be advised before fetal reduction.     

Biophysical profile with amniotic fluid volume assessments

OBJECTIVE: To compare the amniotic fluid index (AFI) with the single deepest pocket technique along with the other components of the biophysical profile (BPP) in predicting an adverse pregnancy outcome. METHODS: Prospective, randomized trial of amniotic fluid assessment by AFI or single deepest pocket during a BPP. Cesarean delivery for fetal distress was the primary outcome evaluated. RESULTS: The AFI was used in 273 pregnancies and the single deepest pocket in 264. The AFI significantly increased the number of pregnancies labeled as oligohydramnios, 102 women (38%) compared with 46 women (17%; P <.001), odds ratio (OR) = 2.84, 95% confidence interval 1.90-4.25 in the single deepest pocket group. There was no difference in the number of women with oligohydramnios in the AFI group, 16 of 102 (16%), undergoing a cesarean delivery for fetal intolerance of labor compared with the single deepest pocket group, 6 of 46 (13%; P =.676). More women with normal fluid by the AFI method (AFI > 5), 20 of 170 (12%), underwent a cesarean delivery for fetal distress than the women with normal fluid by the single deepest pocket technique (2 cm x 1 cm pocket present) group, 12 of 218 (6%; P =.037, OR = 2.22, 95% confidence interval 1.05-4.70). CONCLUSION: The AFI offers no advantage in detecting adverse outcomes compared with the single deepest pocket when performed with the BPP. The AFI may cause more interventions by labeling twice as many at-risk pregnancies as having oligohydramnios than with the single deepest pocket technique.     

Pregnancy outcome after multifetal pregnancy reduction.

OBJECTIVE: To study the effects of multifetal pregnancy reduction (MFPR) as a means to reduce the adverse outcome of multiple gestations. METHODS: This was a retrospective study evaluating the outcome of 334 multiple pregnancies after embryo reduction. RESULTS: In 313 multiple pregnancies in which MFPR was performed before 15 weeks, the rates of miscarriage, preterm delivery <33 weeks, preterm delivery <36 weeks and total fetal loss were 9.12%, 13.33%, 38.60% and 16.25%, respectively, and median gestational age at delivery was 35 weeks. There was a significant correlation between miscarriage and the finishing number of fetuses. In 185 triplets reduced to twins, miscarriage, preterm delivery <33 weeks, preterm delivery <36 weeks and total fetal loss occurred in 8.25%, 11.18%, 40.59% and 15.41% of cases, respectively, and median gestational age at delivery was 36 weeks. In the subgroup of 32 reduced triplet pregnancies that also had second-trimester amniocentesis, the risk of miscarriage (3.13%) was not significantly different from that in the rest of the group. Among 21 twin pregnancies that had selective termination at or after 15 weeks, the risk of preterm delivery <33 weeks was three times higher than in the group of 22 twin pregnancies with first-trimester procedures. CONCLUSION: MFPR resulted in at least one live neonate in 83.75% of cases and was effective in reducing the risks of pregnancy loss and severe prematurity in quadruplets and higher-order pregnancies. The risk of miscarriage increased with increasing finishing number of fetuses. In reduced triplets gestation was prolonged in comparison with average figures reported in the literature. In twin pregnancies selective termination in the first trimester carries a lower risk of severe preterm delivery and this emphasizes the need for first-trimester diagnosis.     

Delayed delivery of second twin: a multicentre study of 35 cases

OBJECTIVE: The aim of this study was to conduct a statistical analysis to determine the outcome of conservative treatment after delivery of a first fetus in multiple pregnancy and thus define new prognostic factors. STUDY DESIGN: Multicentre retrospective study involving 12 centers over a 10-year period. RESULTS: Twenty-eight twin pregnancies and seven triplet pregnancies which were managed conservatively. In twin pregnancies, 79% of the delayed-delivery fetuses survived; only 7% of the first delivered fetuses survived. The mean interval between deliveries was 47 days. No statistical difference was found concerning cerclage, antibiotic therapy, tocolysis and hospitalization. Earlier delivery of the first twin and premature rupture of membranes for the second twin were significantly related to a longer interval between deliveries. CONCLUSION: Delayed delivery in multifetal pregnancies can be successful if there are no contraindications and these pregnancies are managed in a tertiary perinatal center. Publications limited to successful cases have undoubtedly introduced some bias in assessment.     

减胎术联合宫颈环扎术治疗多胎妊娠并宫颈机能不全2例临床分析

多胎妊娠、宫颈机能不全等均是流产或早产的高危因素,若多胎妊娠患者合并宫颈机能不全则流产或早产的风险更高。现报道2例多胎妊娠合并宫颈机能不全患者,分别在孕11+5周和20+5周行减胎术,随后分别在13+4周和21+6周行宫颈环扎术,定期产检阴道超声监测宫颈长度并及时预防早产治疗,分别在孕36周和孕33+4周成功顺产活婴,认为减胎术是多胎妊娠改善妊娠结局的补救措施,减胎术后行宫颈环扎术可修复宫颈的机能,而定期随访对防治早产、指导临床用药及适时拆除宫颈环扎线并改善母儿预后至关重要。当多胎妊娠合并宫颈机能不全时,采用减胎术联合宫颈环扎术进行治疗是一个可供临床借鉴的选择方案。     

双胎之一胎死宫内的诊治

随着促排卵技术和辅助生殖技术的发展，多胎妊娠发生率逐年增多。与单胎妊娠相比，多胎妊娠围产儿病死率更高。双胎之一胎死宫内属于双胎妊娠的严重并发症，一胎死亡后会对存活胎儿有潜在、长期的影响，可引起存活胎儿死亡、神经系统损伤、早产及相关后遗症等，因此，孕期应加强母儿监护。及时诊断和处理是改善围产儿结局的关键。     

Factors affecting fetal presentation in twin pregnancies across gestation

Abstract

Objective: To describe pregnancy characteristics associated with the occurrence of spontaneous version in twin pregnancies from 20 weeks until delivery.

Study design: Review of ultrasound and pregnancy data for all twin pregnancies delivered >24 weeks by one Maternal–Fetal Medicine practice from June 2005–May 2012. For each 4-week gestational age window, fetal presentations were recorded, as well as the likelihood of the final presentation being vertex for Twin A and vertex for both twins. Case–control analysis was performed to estimate associations between pregnancy characteristics and spontaneous version of Twin A.

Results: A total of 491 twin pregnancies were included. The distribution of fetal presentations changed significantly from 20 weeks to delivery, but the presentation at each gestational age interval was significantly associated with the final position of Twin A and the likelihood of vertex–vertex presentation at delivery. The likelihood of spontaneous version of Twin A decreased from 27.9% after 24–27 6/7 weeks, to 18.8% after 28–31 6/7 weeks, to 8.2% after 32–35 6/7 weeks. Pregnancy characteristics associated with spontaneous version of Twin A were a prior vaginal delivery and increased fetal size of either twin.

Conclusions: The likelihood of spontaneous version of Twin A decreases as pregnancy advances. Parity and increased fetal size are associated with spontaneous version.     

What prenatal diagnosis should be offered in multiple pregnancy?

The issues surrounding prenatal diagnosis in multiple pregnancy are complex. Accurate determination of chorionicity is vital and an inability to determine this should trigger consideration for referral to a specialist. The choice of screening method for detection of chromosomal abnormality is limited, and existing data demonstrates the advantages of nuchal translucency screening. The possibility of obtaining discordant results and options for management should be discussed in advance. Invasive tests are technically more difficult and associated with a higher risk of procedure-related pregnancy loss than less invasive methods. Repeat invasive testing is required more often in multiple pregnancies than in singleton pregnancies. Selective termination is technically feasible in both mono- and dichorionic pregnancies, although the risks are higher with the former. It is likely to be more acceptable than high-order multifetal reduction performed in the absence of fetal abnormality.     

Fetal sinus bradycardia and the long QT syndrome

OBJECTIVE: Recent evidence in literature shows that the long QT syndrome accounts for a fraction of the sudden infant death syndrome. Newborn infants with prolongation of the Q-T interval often show sinus bradycardia, which led us to test whether children who were diagnosed with long QT syndrome also show sinus bradycardia in the cardiotocogram before birth. STUDY DESIGN: We identified 18 children who were born from singleton pregnancies at or near term in whom long QT syndrome (corrected QT interval, >0.440 second) was diagnosed after birth or in childhood. Cardiograms during pregnancy and delivery were available from 17 of the 18 children. RESULTS: The cardiotocogram showed persistent fetal sinus bradycardia (baseline heart rate permanently below 120 beats/min) in 12 of 17 fetuses (71%) with long QT syndrome. Two fetuses had additional intermittent tachyarrhythmias. CONCLUSION: Sinus bradycardia in the cardiotocogram during delivery or in pregnancy may indicate long QT syndrome in the fetus. Postnatal electrocardiography should be performed in these children to rule out or confirm a prolongation of the Q-T interval.