By retrieving records from Taiwan's National Health Insurance (NHI) system's database, the current study aimed to investigate the impacts of hysterosalpingography (HSG) to patients after ectopic pregnancy (EP) operations in Taiwan.In this retrospective cohort study, insurance claims data from 1997 to 2013, derived from a cohort of 1 million people randomly sampled to represent all NHI beneficiaries, were analyzed. Patients after ectopic pregnancy (EP) operations were identified via the inclusion of the corresponding NHI procedure codes. We further divided the patients into 2 groups by whether received subsequent HSG, EP-HSG, and EP-no-HSG. Patients with history of previous pregnancies (PP) and subsequent HSG were grouped as PP-HSG. We sought to evaluate the following pregnancies (FP) rate, interval to FP in EP-HSG compared with that in EP-no-HSG, and PP-HSG.EP-HSG had significantly higher FP rate odds ratio than EP-no-HSG (OR, 1.64; 95% CI, 1.24-2.16, P < .001). EP-HSG had lower FP rate odds ratio than that in PP-HSG, but no significant difference (33.1% vs 34.6%, P = .654). The INTERVAL(HSG-FP) in EP-HSG was no significantly different from that in PP-HSG (843.34 ± 82 days vs 644.72 ± 24.30 days, P = .077). There was significant positive correlation between FP after EP and number of HSG (r = 0.070, P < .001). There were significant negative correlation between FP and EP age (r = -0.270, P < .001), FP and INTERVAL(EP-HSG) (r = -0.212, P = .001). The multivariate analysis showed that INTERVAL(EP-HSG) less than 1 year is the predictor factor of INTERVAL(EP-FP) (hazard ratio: 1.422; 95% CI: 1.130-1.788; P = .003). It was evident that the longer the INTERVAL(EP-HSG), the lower the FP rate odds ratio; and the older the EP age, the lower the FP rate odds ratio. (OR, 95% CI; >1 year: 0.59, 0.41-0.86; >2 year: 0.42, 0.32-0.55; >25 years old: 0.47, 0.38-0.57; >30 years old: 0.29, 0.24-0.35; >35 years old: 0.12, 0.08-0.18, all P < .001).Receiving HSG after EP, short INTERVAL(EP-HSG), EP age less than 30 years old, had significant positive impacts on the FP. We encourage shortening the INTERVAL(EP-HSG), and the counseling of women on the most appropriate way to conceive thereafter.