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.