Analysis of Multiple Gestation Pregnancies within a Cohort of Mom-Baby Dyads
Posted in SBSM
- Authors: Yuhan Ma, Carol Davis
Introduction:
Many scholars have researched healthcare costs and maternal outcomes associated with singleton and multiple births. The results demonstrate significant variations in prematurity rates, morbidity, mortality, and length of hospital stay (Thekkeveedu et al., 2021), with more adverse outcomes for multiples. On average, combined all-cause healthcare expenses for mothers with twins or higher-order multiple births were approximately 5 and 20 times higher than for singleton deliveries, respectively (Lemos et al., 2013). In our research, when analyzing pregnancy-level costs, we used baby number 1 for all deliveries, regardless of singleton or multiple births, assuming that financial and maternal outcomes among twin siblings are similar. We aim to validate this assumption and methodology, seeking to include these cases without distorting analysis and comparison of subgroups within the total cohort.
Data:
The dataset comprises prenatal patients delivered at MedStar Washington Hospital Center from June 2020 to December 2022, including 7,825 live births, among which there were 122 sets of twins and 4 sets of triplets.
Methods:
To compare singleton and multiple birth groups, we directly analyzed the average financial outcomes and premature birth rates. We used three analytical methods within the twins and triples groups: paired t-test, coefficient of variance, and comparing the first baby’s costs to the total twin expenses.
Results:
From both financial and maternal outcome perspectives, there is a disparity between twins and singletons. The average cost and payments for twins are more than three times that for singletons. The preterm birth rate among twins is also dramatically higher at 62.8% compared to 10.8% for singletons. Additionally, twins’ low birth weight rate stands at 67.9%, in contrast to just 9.7% for singletons.
Based on our analysis, the number of mother-twin pairs where the coefficient of variation (CV) for the cost between the two babies is less than 0.1 is approximately the same as the number of pairs where the cost of the first baby falls between 45% and 55% of the total cost – nearly 62% of twins meet this cost similarity criterion. For payments, this percentage drops slightly to 45%. In addition, differences were not statistically significant between twins.
We observe nearly 20 sets (16%) of twins (Figure 1) where the coefficient of variation (CV) exceeds 0.6 for both cost and payment, indicating significant differences. Upon closer examination, we found that this occurs when one twin stays in the hospital for only a few days or hours while the other remains for more than two weeks.
Recommendations for Practice
We recommend a more nuanced approach for cases involving multiples. Going forward, mother-baby pairs where the coefficient of variance (of cost) for related neonates exceeds 0.6, these cases should be excluded from the study sample as outliers unless the sample size is large enough to withstand and be analyzed separately as with other high-racuity cases.
References
1Kalikkot Thekkeveedu, R., Dankhara, N., Desai, J., & al., e. (2021). Outcomes of multiple gestation births compared to singleton: Analysis of multicenter KID database. Maternal Health, Neonatology and Perinatology, 7(1), 15. https://doi.org/10.1186/s40748-021-00135-5
2Lemos, E. V., Zhang, D., Van Voorhis, B. J., & Hu, X. H. (2013). Healthcare expenses associated with multiple vs singleton pregnancies in the United States. American Journal of Obstetrics & Gynecology, 209(6), 586.e1-586.e11. https://doi.org/10.1016/j.ajog.2013.10.005