['To assess the fertility of patients treated conservatively for a Stage II or III borderline ovarian tumour.', 'A retrospective study.', 'Gynaecological oncology department in a French anti-cancer centre.', 'Seventeen patients treated with conservative management for a Stage II (n = 6) or III (n = 11) borderline ovarian tumour were followed up. Fifteen patients underwent a unilateral salpingo-oophorectomy (with contralateral cystectomy in six patients), one had unilateral cystectomy and one a bilateral cystectomy. Fourteen patients had non-invasive implants and three had invasive implants.', 'Pregnancy rates and outcome.', 'Eight pregnancies were observed in seven patients in a median delay of eight months following the surgical procedure. Six pregnancies were observed spontaneously, one occurred after an ovarian stimulation and one after an IVF procedure. None of these patients recurred under the form of invasive ovarian carcinoma on the spared ovary. Two patients (one with a non-invasive disease and one with an invasive one) had recurrence in the form of evolutive invasive implants, but neither woman died.'] Does fertility result after conservative treatment of advanced stage serous borderline tumour of the ovary?