SummaryobjectIve. This study aimed to evaluate the perinatal outcome of twin pregnancies delivered in a tertiary teaching hospital according to chorionicity. Methods. A retrospective study involving 289 twin pregnancies delivered from January 2003 to December 2006 was carried out. Maternal and perinatal data were obtained from hospital charts and delivery logs. Chorionicity was determined by ultrasonography or histopathological study. results. Incidence of twin gestations was 3.4% and 96.4% were spontaneously conceived. 60.5% were dichorionic (DC), 30.8% of monochorionic diamniotic (MCDA), 6.6% monochorionic monoamniotic (MCMA) and for 2.1% chorionicity was unknown. The mean gestation age at delivery was respectively 35.4, 33.6, 32.9 for DC, MCDA and MCMA. The mean birth weight was 2.171, 1.832 and 1.760 g respectively for DC, MC and MCMA. The proportion of fetuses delivered with less than 34 weeks in DC was of 21.7%, while in MCDA it was of 39.3% and in MCMA of 42.1%. Birth weight below the 10 th centile occurred in 15.7% for DC, 22.5% for MCDA and 26.3% in MCMA. Congenital anomalies were observed in 21.3% in monochorionic and in 7.4% in the dichorionic. Lenght of hospital stay was shorter for DC when compared to MCDA and MCMA twins (13.1, 17.3 and 23.3 days, respectively). The proportion of twin pregnancies with both babies discharged alive were 85.7% in DC and 61.1% in MC. conclusIon. The rate of preterm deliveries and low birth weight is higher in monochorionic pregnancies when compared to dichorionic twins. However, when adjusted for complications such as fetal abnormalities and twin-twin transfusion syndrome, double survival rates were similar in the two groups.

OBJECTIVE:The purpose of this study was to establish longitudinal reference ranges for fetal ultrasound biometry measurements and growth parameters in twin pregnancies.METHOD:A total of 200 uncomplicated twin pregnancies before 21 weeks of gestation were recruited for this prospective, longitudinal study. Women who abandoned follow-up, pregnancies with unknown outcomes or pregnancies with complications were excluded. Ultrasound scans were performed every three weeks, and biparietal and occipitofrontal diameters, head and abdominal circumferences, and femur diaphysis length measurements were obtained for each fetus at each visit. Estimated fetal weight, biparietal/occipitofrontal diameter, head circumference/abdominal circumference, and femur diaphysis length/abdominal circumference ratios were also calculated. Multilevel regression analysis was performed on normalized data.RESULTS:A total of 807 ultrasound examinations were performed in 125 twin pregnancies between 14 and 38 weeks of gestation (6.5±1.4 scans/pregnancy). Regression analysis demonstrated significant correlations for all variables with gestational age, namely log of the biparietal diameter (r = 0.98), log of the occipitofrontal diameter (r = 0.98), log of the head circumference (r = 0.99), log of the abdominal circumference (r = 0.98), square root of the femur length (r = 0.99), log of the estimated fetal weight (r = 0.99), biparietal/occipitofrontal ratio (r = -0.11), head/abdomen circumference ratio (r = -0.56), and log of the femur length/abdominal circumference ratio (r = 0.61). Values corresponding to the 10th, 50th, and 90th percentiles for estimated fetal weight at 28, 32, and 36 weeks, respectively, were as follows: 937, 1,096, 1,284 g; 1,462, 1,720, 2,025 g; and 2,020, 2,399, 2,849 g.CONCLUSION:In twin pregnancies, fetal ultrasound biometry measurements and growth parameters show a significant correlation with gestational age.

The rate of decline in fetal hemoglobin levels between first and second transfusions in alloimmune disease can be predicted by a combination of hemoglobin levels after the first transfusion, interval between both procedures, and middle cerebral artery systolic velocity before the second transfusion.

LV myocardial performance not only remains preserved but also is actually enhanced in cases of moderate/severe fetal anemia.

Left ventricle MPI increases significantly after intrauterine blood transfusion and greater changes are associated with procedures at an earlier gestational age, lower pre-transfusion MPI z-scores and smaller feto-placental volume expansion.