Objective To investigate the effect of high-intensity focused ultrasound (HIFU) ablation for uterine fibroids on pregnancy.Design A retrospective observational study.Setting Department of Gynaecology in a single centre in China.Population Patients with uterine fibroids who wish to become pregnant.Methods Patients with uterine fibroids who wished become pregnant and have children, were treated using HIFU from April 2011 to March 2016 at Chongqing Haifu Hospital. Pregnancy outcomes were analysed.Main outcome measures Pregnancy outcomes after undergoing USgHIFU.Results After the HIFU treatment, the 78 patients had 80 pregnancies, in which 76 cases were natural pregnancies and four were test-tube pregnancies. Of the 78 patients who became pregnant, nine patients had complicated primary or secondary infertility before the HIFU treatment, 13 patients had had at least two miscarriages or missed miscarriages, one patient had had a stillbirth; none had undergone other special treatment. After the HIFU treatment, the average time to pregnancy was 5.6 AE 2.7 months. There were 15 cases of full-term normal delivery and 56 cases of caesarean, including three cases of premature caesarean. After the treatment, three patients had a miscarriage (one patient's progesterone level was lower than the normal value; and the other two miscarriages were for unknown reasons), two patients became pregnant 3 months after complete curettage of uterine cavity and had full-term normal deliveries, one patient planned to use contraception after complete curettage of the uterine cavity; and one patient had her labour induced (after 13-weeks pregnancy). The fetuses of all the patients developed well during both the pregnancy and child-bearing without uterine rapture or perinatal and postpartum complications.Conclusion HIFU treatment can effectively treat patients with uterine fibroids who wish to have children; it could significantly reduce the preparation period for pregnancy after the operation. It can also improve the fertility of patients with a history of infertility and abnormal pregnancy and child-bearing, with no additional obstetric risks.Keywords High-intensity focused ultrasound, pregnancy, uterine fibroid.Tweetable abstract As a noninvasive therapeutic technique, HIFU safely can be used to treat patients with uterine fibroids who wish to become pregnant.