Prospective risk of intrauterine death of monochorionic-diamniotic twins

Abstract

Objective: The purpose of this study was to calculate the prospective risk of fetal death in monochorionic-diamniotic twins. Study design: We evaluated 193 monochorionic diamniotic twin pregnancies that were followed and delivered after 24 weeks. Surveillance included cardiotocography and sonography performed at least once weekly. The prospective risk of fetal death was calculated as the total number of deaths at the beginning of the gestational period divided by the number of continuing pregnancies at or beyond that period. Results: The fetal death rate was 5 of 193 pregnancies (2.6%; 95% CI, 1.1, 5.9); the prospective risk of stillbirth per pregnancy after 32 weeks of gestation was 1.2% (95% CI, 0.3% -4.2%). Conclusion: Under intensive surveillance, the prospective risk of fetal death in monochorionicdiamniotic pregnancies after 32 weeks of gestation is much lower than reported and does not support a policy of elective preterm delivery. Ó 2006 Mosby, Inc. All rights reserved.Monochorionic twins, comprising approximately 20% of all spontaneous twins and nearly 5% of iatrogenic twins, 1 are at a substantial higher risk of perinatal morbidity and death than their bichorionic counterparts.2-4 This risk is attributed to the inherent pathologic condition that is associated with delayed zygotic splitting that leads to the increased prevalence of fetal and placental malformations. However, in monochorionicdiamniotic pregnancies, the precise cause of the high rate of adverse perinatal outcomes in pregnancies that are not complicated by congenital anomalies, twin-twin transfusion syndrome (TTTS), and/or growth restriction is not clear.Evidently, not all monochorionic twin pregnancies are complicated a priori. A recent analysis of a large cohort of 455 monochorionic twins showed that 181 (39.8%) twin pairs were considered ''uncomplicated'' (ie, without signs of TTTS and exhibiting appropriate and concordant growth in each of the structurally normal twins). 5 This subset of ''uncomplicated'' monochorionic twins, however, was found to be at a considerable excess

Perinatal mortality and mode of delivery in monochorionic diamniotic twin pregnancies ≥32 weeks of gestation: a multicentre retrospective cohort study

“…Fetal death in MC twins might be prevented by intensive monitoring, as was described by Simões et al 8 However, despite their intensive follow-up, the incidence of IUFD is similar to that of this study in which pregnancies were monitored fortnightly. To date, it is unknown how frequently MC twin pregnancies should be monitored to prevent fetal death.…”

“…Intrauterine fetal death (IUFD) rates from 32 weeks of gestation vary, leading to diverse recommendations on the optimal timing of delivery. 1,5,[7][8][9][10][11][12] The same holds as to the mode of delivery in relation to perinatal mortality. [13][14][15][16][17][18] However, previous studies on the subject have a small sample size, ranging from 50 to 160 continuing pregnancies ‡32 weeks of gestation, hampering reliable clinical recommendations.…”

“…These studies have reported varying IUFD rates from 32 weeks of gestation with subsequent diverse recommendations on this issue. 1,5,[7][8][9][10]33 However, retrospective analysis of mortality rates may have introduced a study bias in those small cohorts. In this study, the prospective risk of fetal demise at 32, 35 and 37 weeks is 0.5%, 0.3% and 0.5%, respectively.…”

MFM/geneticist view on prenatal management of twins

“…Close observation of MC/DA is warranted. Some authors electively deliver MC/DA twins between 34 and 36 weeks (in some cases after administration of steroid or confirmation of fetal lung maturity) due to the increased risk of stillbirth in this type of twin gestation [Barigye et al, 2005;Simoes et al, 2006;Lee et al, 2008]. Based on these studies, pregnancies should not go beyond 38 weeks without very close monitoring.…”

Monochorialität: Risiken und intrauterine Therapie

“…SSW war 1,2%, wobei in beiden Fällen (3 Feten) ausgeprägte Wachstumsretardierungen vorlagen. Dieses Ergebnis stimmt überein mit dem einer früheren Untersuchung [24]. Insgesamt zeigte un- …”