OBJECTIVE: To assess the frequency of cervical pregnancy (CP) in women undergoing assisted reproductive techniques (ART) and to ascertain its risk factors DESIGN: Case-control study. Two control groups were established: tubal ectopic pregnancies and intrauterine pregnancies. SETTING: 25 private assisted reproduction clinics run by the same group in Spain PATIENT(S): Women undergoing ART (artificial insemination, or IVF with own or donor oocytes). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Frequency of CP. Ascertainment of demographic and clinical risk factors. Assessment of the influence of IVF parameters on CP risk. RESULT(S): There were 32 CPs out of 91,067 ongoing pregnancies, yielding a rate of 3.5/10,000. CPs represented 2.02% of all ectopic pregnancies (32/1582). The main risk factors were: ≥ 2 previous pregnancies (OR= 2.68; CI=1.18-6.07), ≥2 previous miscarriages (OR= 4.21, CI=1.7- 10.43), ≥ 2 previous curettages (OR=4.71; CI= (1.19-18.66) and smoking (OR= 2.82 (1.14-6.94). History of cesarean sections and tubal pregnancy were not associated with an elevated CP risk. Infertility conditions and endometrial thickness were similar across the three groups. The proportion of women from whom < 10 oocytes were retrieved was higher in the CP group than in either of the control groups. CONCLUSION(S): In ART, the main risk factors for ectopic pregnancy are a history of at least 2 pregnancies/miscarriages/curettages, and smoking. IVF parameters do not seem to influence the development of CP. CP is less common in ART than previously reported, likely attributable to improvements in ART, although a publication bias cannot be ruled out in early IVF reports.