We studied the possible relationship among parity, female sterilization, hysterectomy and the risk of primary fallopian tube carcinoma (PFTC) in a case-control study in Finland in cases occurring between 1975 and 2004. A total of 573 PFTC cases were identified from the Finnish Cancer Registry, and 10 age-matched controls per case were randomly selected from the Finnish Central Population Registry. In multivariate analysis (including 189 PFTC cases and 1764 controls) parity was protective: the odds ratio (OR) for 1-2 deliveries was 0.63 (95% CI 0.44-0.91) and for > or =3 deliveries, 0.32 (95% CI 0.19-0.52). The OR for sterilization was 0.74 (95% CI 0.42-1.30) and for hysterectomy 1.27 (95% CI 0.73-2.21). Our findings suggest a possible hormonal background as regards the development of PFTC.