If you think of an embryo as a baby, the uterine cavity is the room in which the baby lives. The embryo is very “picky” and must be warm, comfortable and the right size to live in. Therefore, before the embryo is implanted, the doctor will go through your room very “hard” to make sure it is ready. Not only must the inside of the room be dry and clean, but also the walls (i.e., the myometrium) must not have any oversized debris in the middle that could affect the shape and design of the room, and the outside of the room must not have any standing water (e.g., fluid in the fallopian tubes). Uterine fibroids are masses that occur in the uterus and are common benign tumors in women of childbearing age. Infertility due to fibroids alone accounts for about 3% of cases. The impact of different types of fibroids on fertility varies. The presence of fibroids is like a stone. The fibroids in the “room” (i.e. submucosal fibroids) must be removed before embryo transfer. A stone between the walls (i.e., intermural myxoma) does not usually affect the design of the room, but a stone between the walls that is too large can affect the size and shape of the space in the room. Stones outside the room (submural fibroids) have no effect on the room and can be ignored for the time being. Professionally, stones outside the room (subplasmic fibroids) have no significant effect on conception and pregnancy outcomes; stones in the next room, i.e., interstitial fibroids growing in the myometrium, >4 cm in diameter, have been studied to decrease pregnancy rates and increase miscarriage rates. Fibroids growing under the uterine mucosa are the stones in the room and have an undoubted impact on embryo implantation because they change the volume and shape of the uterine cavity. In addition, the location and size of fibroid growth are associated with infertility. If fibroids cause changes in the morphology of the cervical uterine cavity and fallopian tube opening, resulting in blockage of the uterine cavity and fallopian tubes, they directly affect the transport of sperm and fertilized eggs and embryo implantation. Larger interstitial myomas can lead to normal alignment of uterine muscle fibers and alter the polarity of uterine contraction waves, thus affecting sperm transport and embryo implantation. In addition, the endometrium surrounding the myoma exhibits glandular hyperplasia and polyp formation, and its accompanying hyperestrogenic environment can interfere with conception. Most leiomyomas are easier to detect with associated sonographic changes on routine ancillary examinations such as ultrasound. For suspected submucosal fibroids found during treatment, doctors often arrange hysteroscopy to further confirm the intrauterine environment. If submucosal fibroids are found at hysteroscopy, further hysteroscopic electrosurgery is required. Larger fibroids that compress the endometrium need to be treated by laparoscopic or open myomectomy, otherwise they may affect the rate of embryonic implantation and increase the risk of miscarriage in the future. After myomectomy, due to scar healing, it is usually necessary to rest for about 1 year before pregnancy can be arranged, otherwise there is a higher risk of uterine rupture. For fibroids that do not require surgical treatment and can be temporarily observed, annual ultrasound examinations can be performed to monitor the size of the fibroids. If the size increases rapidly in a short period of time, an outpatient visit is required. Short-term use of ovulation-promoting drugs generally has little effect on the growth of fibroids, and frequent ultrasound monitoring during the ovulation-promoting process can also reduce concerns about the growth of fibroids. This shows that the “stay” or “no stay” of fibroids requires a comprehensive assessment by an “environmental expert” (doctor). As the “head of the house” of the uterus, women should listen carefully to the advice and work together to clean the house and prepare for the joy of a new life. Good pregnancy, let’s go.