Intrauterine growth restriction in monochorionic-diamniotic twins / Restrição de crescimento intrauterino em gêmeos monocoriônicos diamnióticos.

Objective: to evaluate neonatal morbidity and mortality in monochorionic- -diamniotic (MCDA) twin pregnancies complicated by selective intrauterine growth restriction (sIUGR) and non-selective intrauterine growth resctriction (nsIUGR). Methods: neonatal morbidity parameters and mortality were analyzed in 34 twins with IUGR (< 10th percentile on twins’ growth charts): 18 with sIUGR and 16 with nsIUGR. The sIUGR group was made up of 18 pregnancies in which growth was restricted in only one fetus (n = 18). The nsIUGR group was composed of 8 pregnancies in which both fetuses presented restricted growth (n = 16). Cases of twin-to-twin transfusion syndrome and fetal malformation were not included in the study. Results: the MCDA twin pregnancies with sIUGR had a higher rate of orotracheal intubation (p = 0.001) and mechanical ventilation (p = 0.0006), as well as longer than average fasting time (p = 0.014) compared to those in which the fetuses had nsIUGR. A higher incidence was also observed of types II and III umbilical artery Doppler velocimetry patterns in the sIUGR cases (p = 0.002). There was no significant difference between the two groups as to mortality during pregnancy and the neonatal period (p = 0.09). Conclusion: in MCDA twin pregnancies, sIUGR presents more severe umbilical artery Doppler velocimetry abnormalities and worse morbidity than nsIUGR. .

Objetivo: avaliar a morbidade e mortalidade neonatal em gestações monocoriônicas e diamnióticas (MCDA) acometidas pela restrição de crescimento fetal seletiva (RCFS) e não seletiva (RCFNS). Métodos: os parâmetros de morbidade e mortalidade neonatais foram avaliados em 34 gêmeos com RCF (abaixo do percentil 10 de uma curva de crescimento para gêgêmeos): 18 com RCFS e 16 com RCFNS. O grupo com RCFS teve origem em 18 gestações, em que somente um feto apresentava RCF. O grupo com RCFNS teve origem em 8 gestações em que ambos os fetos apresentavam RCF. Foram excluídos deste estudo casos da síndrome da transfusão feto-fetal e malformações fetais. Resultados: os gêmeos de gestações MCDA com RCFS apresentaram maior frequência de entubação orotraqueal (p=0,001), ventilação mecânica (p=0,0006) e maior tempo em jejum durante internação (p=0,014), quando comparados aos gêmeos de gestações MCDA com RCFNS. No grupo com RCFS, também foram observados maior frequência de tipos II e III de dopplervelocimetria de artéria umbilical (p=0,002). Não houve diferença significativa entre os grupos quanto à mortalidade neonatal (p=0,09). Conclusão: em gestações gemelares MCDA, a RCFS representa maior frequência de alterações severas na velocimetria Doppler da artéria umbilical e piores resultados na morbidade neonatal. .

Malformaciones congénitas en gemelos / Congenital malformations in twins

Background: A higher prevalence of congenital malformations among twins than among single has been reported in the literature. Aim: To study the incidence of congenital malformations in twins in the maternity hospital of the University of Chile in the period 1983-1997. Material and methods: As part of the Latin American Collaborative Study of Congenital Malformations, every newborn in the maternity hospital was examined by a neonatologist and congenital malformations were recorded in a special file. Results: In the study period there were 48.663 deliveries of single pregnancies and 448 deliveries of twin pregnancies, giving birth to 886 twins borns alive and 17 stillbirths (1.9 percent mortality). Of these, there were 423 twins, 17 triplets, a sextuple delivery and two siamese. Seven point one percent of twins born alive and 6.5 percent of single newborns had a congenital malformation. The prevalence of malformations in twins and single stillbirths was 35.2 and 17.2 percent respectively (p <0.04). In four pairs and siamese newborns, malformations typical of monozygotic twins were present, such as an acardiac fetus with Trap sequence, a papyraceous fetus and two with hydroanencephaly. Twelve twins had malformations attributable to uterine compression. Conclusions: This study did not find a higher frequency of malformations comparing twins with single babies born alive, but in stillbirths there was a significant difference between single and twin stillbirths (7.1 percent versus 35.2 percent, respectively, p <0.05)