The outcome of reduced and non-reduced triplet pregnancies managed in a tertiary hospital during a 15-year-period - a retrospective cohort study.

OBJECTIVES: Triplet pregnancies involve several complications, the most important being prematurity as virtually all triplets are born preterm. We conducted this study to compare the outcomes of reduced vs. non-reduced triplet pregnancies managed in the largest tertiary hospital in Finland. METHODS: This was a retrospective cohort study in the Helsinki University Hospital during 2006-2020. Data on the pregnancies, parturients and newborns were collected from patient records. The fetal number, chorionicity and amnionicity were defined in first-trimester ultrasound screening. The main outcome measures were perinatal and neonatal mortality of non-reduced triplets, compared to twins and singletons selectively reduced of triplet pregnancies. RESULTS: There were 57 initially triplet pregnancies and 35 of these continued as non-reduced triplets and resulted in the delivery of 104 liveborn children. The remaining 22 cases were spontaneously or medically reduced to twins (9) or singletons (13). Most (54.4 %) triplet pregnancies were spontaneous. There were no significant differences in gestational age at delivery between triplets (mean 33+0, median 34+0) and those reduced to twins (mean 32+5, median 36+0). The survival at one week of age was higher for triplets compared to twins (p<0.00001). CONCLUSIONS: Most pregnancies continued as non-reduced triplets, which were born at a similar gestational age but with a significantly higher liveborn rate compared to those reduced to twins. There were no early neonatal deaths among cases reduced to singletons. Prematurity was the greatest concern for multiples in this cohort, whereas the small numbers may explain the lack of difference in gestational age between these groups.

Correction to: Perinatal outcomes in Finnish twins: a retrospective study.

An amendment to this paper has been published and can be accessed via the original article.

Perinatal outcomes in Finnish twins: a retrospective study.

BACKGROUND: To establish the changes in perinatal morbidity and mortality in twin pregnancies in Finland, a retrospective register research was conducted. Our extensive data from a 28-year study period provide important information on the outcome of twin pregnancies in Finland that has previously not been reported to this extent. METHODS: All 23,498 twin pregnancies with 46,996 children born in Finland during 1987-2014 were included in the study. Data were gathered from the Medical Birth Register and the Hospital Discharge Register (Finnish Institute for Health and Welfare, Finland) regarding perinatal mortality (PNM) and morbidity. For statistical analysis, binomial regression analysis and crosstabs were performed. The results are expressed in means, percentages and ranges with comparison to singletons when appropriate. Odds ratios from binomial regression analysis are reported. A p-value <0.05 was considered statistically significant. RESULTS: There were 46,363 liveborn and 633 stillborn twins in Finland during 1987-2014. Perinatal mortality decreased markedly, from 45.1 to 6.5 per 1000 for twin A and from 54.1 to 11.9 per 1000 for twin B during the study period. Yet, the PNM difference between twin A and B remained. Early neonatal mortality did not differ between twins, but has decreased in both. Asphyxia, respiratory distress syndrome, need for antibiotics and Neonatal Intensive Care Unit (NICU) stay were markedly more common in twin B. CONCLUSIONS: In Finland, PNM and early neonatal mortality in twins decreased significantly during 1987-2014 and are nowadays very low. However, twin B still faces more complications. The outline provided may be used to further improve the monitoring and thus perinatal outcome of twins, especially twin B.