What are the prognostic factors in the delivery of the second twin?

Objective To evaluate the prognosis of the second twin according to different criteria (presentation, mode of delivery , term, weight, weight difference between twins ,twin to twin delivery time interval, studying the Apgar scores at birth and neonatal morbidity and mortality. Materials and Methods This is a retrospective study of 183 parturients carrying twin pregnancies collected at the department of Obstetrics-Gynecology in Mahmoud Matri Hospital (Ariana) over a period of 9 years ( 1st January 2001 to 31st December, 2009 ) . Results We recorded 357 live births ( 181 J1 and J2 176 ) and 9 stillbirths . The relationship between the order of the twin and the modality of delivery on the one hand, and between the order of twin and type of presentation was considered significant (p < 0.001). We found no significant difference in Apgar score at 1 minute and 5 minutes between the 1st and the 2nd twins. A term ≤ 34 weeks was a poor prognostic factor for the Apgar score at the first and the fifth minute for the 2 twins but no significant difference between the 1st and 2nd twins (  1st min p=0.4623 ; 5th min p = 0.2899 ). Low birth weight ≤ 1500g were significantly more at risk of foetal suffering (p < 0.001). A birth weight discordance of 25% or more was observed 36 cases (19.7 %). The Apgar score was significantly influenced by the birth weight difference only in the first minute (p = 0.043 ). Thereafter, this difference disappears in the 5th minute. The type of presentation and methods of delivery did not influence significantly the second twin morbidity. A time interval between the birth of the first and second twin greater than 15 minutes was a bad prognostic factor for the Apgar score in the 1st min ( p = 0.001) and 5th min ( p = 0.019) . Transfer rate in neonatology and neonatal distress was 31.2 %.The term of birth ( before 34 weeks ), low birth weight ( ≤ 1500 g ) , and twin-to-twin delivery time interval (≥ 15 min) are parameters that influenced significantly the rate of neonatal distress and transfer to pediatric health care unit (p <0.001 , p<0.001, p = 0.004) . We found a significant increase in the transfer to pediatrics when the birth weight difference was larger than 25% ( p = 0.005). However, no significant difference was found concerning the neonatal respiratory distress (p = 0.22). The different modes of delivery and the type of presentation of the second twin did not significantly alter the rate of neonatal respiratory distress (p = 0.28 , p = 0.53) and transfer Pediatrics (p = 0,63, p = 0.38 ). Among the live births, 5 twins had died in labor room : 1st twin in two cases and in 2nd twin in 3 cases and there was no significant correlation between neonatal mortality and the twin's order (p = 0.629 ) . Conclusion A term ≤ 34 weeks, a low birth weight ≤ 1500g and a delay of more than 15 mn were factors that influenced significantly the Apgar score at 1st and 5th minute, and were responsible for more neonatal distress and transfer in pediatrics. A birth weight difference larger than 25% between the two twins influenced the Apgar score at the first minute and was responsible for an increase in the transfer rate.