Cervical immaturity at 40 weeks, the time of cervical ripening is affected by the position of the fetal head, whether the cervix has been treated or not, and the individual’s physical condition, etc. Fetal malposition, cervical treatment, and excessive toughness of the cervical tissues will slow down cervical ripening, and need to be analyzed specifically. 1. Fetal head position: the fetal position is not correct or the fetal head is not completely in the pelvis, the fetal head can not press the cervix, and can not promote the separation of the cervix and the fetal membranes to promote the dilatation, so it leads to the immaturity of the cervix. 2. The cervix has been treated: after the cervix has been treated, too much fibrous scar tissue is formed during the recovery process, which affects the elasticity of the whole cervix, and the cervix is more hard, so the cervix will be slow to ripen. 3. Individual constitution: If the uterus is excessively tilted back and the cervical tissues are too tough, it will also affect the cervical ripening. Cervical ripening refers to the softening, shortening, disappearing and dilating state of the cervix before the start of labor. 40 weeks of cervical ripening time varies from person to person, and there is no specific number of days. If the cervix is not ripe at 40 weeks, it is recommended to adopt scientific methods to promote cervical ripening under the guidance of the doctor.