Conclusion
In conclusion, women with one unLM or ceLM have a poor prognosis, including a higher risk of miscarriage and a lower live birth rate. This finding stressed the adverse prognostic effect of previous LMs, and would impact the reproductive counselling practice in clinics that women with even only one LM should be informed of the risk and given more intense surveillance during the subsequent pregnancy. Additionally, further prospective cohort studies are still needed to verify our finding and ascertain the mechanisms underlying the reported associations.