Strengths and Limitations
Our research has several strengths. It’s an observational cohort study across two centers and has a longitudinal follow-up for each participant. As a twin pregnant cohort, we have a large number of subjects and owned the whole information of each mother from registration to delivery. We applied PSM and sensitivity analysis to deal with unmatched baseline characteristics, so the conclusions were reliable. To our knowledge, this is the first cohort trial to demonstrate that early pregnancy-initiated LDA could improve the adverse outcomes in twin pregnancies.
As a cohort study based on real-world data, there were some inherent defects. No random was applied in this study, and the baseline characteristics in primary data were not matched, although PSM was applied, we regrettably abandoned a lot of patients for final analysis. Secondary, it is a purely observational study, and usage of aspirin was uncontrolled but uniformed in one medical center. Another shortage of our study was that we just gathered the medical details of patients while other baseline information such as educational background, annual income, and so on were not collected.
Combining with these defects, further multi-center RCTs from multiple centers should be taken into considerations.