MORBIDITY AND MORTALITY OF DISCORDANT TWINS UP TO 34 WEEKS OF GESTATIONAL-AGE

The combination of weight discordance and prematurity implies a high p erinatal morbidity and mortality for the affected twins, Several patho mechanisms may be responsible for the weight difference in twins inclu ding a different genetic growth potential in dizygotic twins, placenta insufficiency in one twin, and chronic fete-fetal transfusion (CFFT). Little is known about neonatal morbidity and mortality of discordant twins. Therefore, a retrospective, case-controlled study on preterm di scordant twins up to 34 weeks gestation was carried out. Twenty-seven (27,3%) of 99 twin pairs born in our clinic had a birth weight differe nce of more than 20%. The control group consisted of 27 non-discordant twins matched for gestational age. Discordant twins showed a signific antly higher mortality (19%) than the control twins (2%). Severe intra cranial haemorrhage (ICH) and persistent ductus arteriosus Botalli (PD A) were found more often in discordant twins than in the control group . The increased mortality and morbidity of discordant twins compared w ith concordant twins matched for gestational age indicates that the in creased morbidity and mortality of preterm weight discordant twins is not only due to prematurity, but is also related to the discordance it self, Thirteen (48.1%) of the weight discordant twin pairs fulfilled t he criteria for CFFT. Twins with CFFT differed significantly from cont rols with respect to the incidence of mortality and the rate of severe ICH, PDA, and the necessity of postnatal cardiopulmonary resuscitatio n. By contrast, no significant differences were found between discorda nt twins without CFFT and controls. Thus, CFFT appears to be a major c ontributing factor for increased mortality and morbidity of weight dis cordant twins. Intra-twin pair analysis revealed a higher rate of post natal hypoglycaemia in the smaller twins only, probably caused by insu fficient glycogen storage due to intra-uterine malnutrition. Mortality was the same for both the larger and the smaller twins. It may be con cluded that neonatal outcome of smaller twins who have survived intra- uterine malnutrition is the same as in larger twins. Intra-twin pair a nalysis in twins with CFFT revealed no significant differences except for a higher rate of ICH grade 2-4 in the larger twins which might be explained by hypervolaemia of the recipient. Conclusion Morbidity and mortality of weight discordant twins are increased. CFFT appears to be a major contributing factor for the increased mortality and morbidity . Postnatal mortality was the same in acceptor and donor; however, the acceptor had a higher postnatal morbidity.