Objective: To investigate the subsequent fertility in women with a history of caesarean scar pregnancy Design: Observational study Setting: Tertiary hospital in China Sample: 149 women treated for caesarean scar pregnancy were followed up for five years. Methods: 53 women had unprotected sexual intercourse attempting to become pregnant again, while most women did not even attempt to conceive. Data including clinical parameters and treatment options at the time of diagnosis, and the outcomes in subsequent pregnancy were collected. In addition, a questionnaire about the menstrual cycle after treatment was voluntarily completed by these women. Main Outcome Measures: The outcomes of subsequent fertility from 53 women were analyzed. Results: Of the 53 women, 46 (84%) women had a subsequent pregnancy, while 7 (14%) women did not. There was no difference in clinical parameters in previous caesarean scar pregnancy or treatment options between the two groups. From the questionnaire, there was no difference seen in the length of the menstrual cycle and menses between the two groups. However, a higher number of women with light menstrual bleeding was seen in women without a subsequent pregnancy (67%), compared with women who did (27%). Furthermore, 6 women (13%) who had a subsequent pregnancy experienced missed miscarriage in the first trimester. Conclusion: We reported that 14% of women treated for cesarean scar pregnancy did not have a subsequent pregnancy, after unprotected sexual intercourse. Light menstrual bleeding after treatment may be one of the reasons for this adverse effect. Our findings need to be further investigated.