With the implementation of the two-child policy and the wide application of hysteroscopy and laparoscopy,pregnancy of scarred uterus women is increasing year by year,and most patients still choose cesarean section.Complications of cesarean section has also increased.It is an important task for obstetricians to master the timing and mode of termination of pregnancy and reduce complications.The authors make a comprehensive analysis of the timing and complications of cesarean section for the second pregnancy of scarred uterus.

Not only should a series of special physiological changes that occur in pregnant women be considerated,but the effects of anesthesia drugs on the fetus should also be considered,in order to conduct a simple,safe,and effective anesthesia in cesarean section surgery.This review will summarize the current selection of anesthesia approachs for cesarean section and the prevention and control of common anesthesia accidents and complications,aiming at guiding the clinical practice,reducing the risk of cesarean section anesthesia,ensuring the maternal and fetal safety and achieving comfort in diagnostic and therapeutic procedure.

The breech presentation is a common occurrence in the obstetrical practice,accounting for about 3-5% of singleton fetuses at delivery.The Term Breech Trial demonstrated the planned cesarean section to be associated with a significant reduction in perinatal mortality and short term morbidity.Although the safety of cesarean section is widely reported,there is still a certain proportion of neonatal injuries,especially fracture.This paper focuses on the neonatal birth injury by cesarean section of breech presentation and the corresponding preventive measures and treatment,in order to reduce the newborn injury as much as possible.

The ureteral injury is one of the significant complication of cesarean section.High risk factors include emergency caesarean section,history of caesarean section,hysterectomy during cesarean section,history of hypogastric zone operation,pelvic infection,etc.The lower uterine segment,especially1.5-3cm from UVJ,is the most common injury level,and more injuries occur on the left side than on the right.It is difficult to recognize the ureteral injuries intraoperatively.Postoperative diagnosis can be made by ultrasound,CTU or retrograde pyelography.Early recognition and repair of the ureteral injury are essential to the patient outcome and preventing late complications and reducing the cost.If the injuries are diagnosed postoperatively,the delayed operation can be performed between 6 weeks and 3months after cesarean section if conditions permitted.The key to avoiding ureteral injury during cesarean section is prevention.This requires us to observe the course of labor closely and handle abnormal labor process in time to avoid emergency caesarean section after long trial.The incidence of ureteral injuries can be reduced by careful operation.

Hemorrhage often occurs during caesarean section,which can lead to severe postpartum hemorrhage if not treated in time.Effective treatment can avoid serious bleeding and following complications.This paper discussed the advantages and disadvantages of various hemostasis schemes,which included uterotonics,uterine cavity tamponade,uterine compression suture,and vascular occlusion.Any hemostasis selected should be used as early as possible to achieve sufficient effect and reduce the morbidity of complications after massive hemorrhage.

As the rate of cesarean section increases,the incidence of pernicious placenta previa increases,and risk of complications also increases.At present,interventional therapy in obstetrics,especially postpartum hemorrhage,has a wide range of application,which may lead to corresponding complications such as puncture site damage,vascular injury,thrombosis,etc.This article focuses on the complications of prophylactic balloon occlusions.

With the opening of the second-child policy and the increase of cesarean section rate,the incidence of surgical site infection after cesarean section also increases,which seriously affects the physical recovery after delivery.In this paper,the types of infection bacteria,high risk factors,prevention,diagnosis and treatment measures are comprehensively expounded.It is emphasized that early identification of risk factors and establishment of effective prevention and treatment measures are essential to reducing the incidence and mortality of incision infection in cesarean section.

As a long-term complication of cesarean section,previous cesarean scar diverticulum(PCSD)has attracted more and more attention in recent 10 years.PCSD increases the risk of two major obstetrical complications:uterine rupture and placenta accreta.Moreover,long-term adverse outcomes include pain,abnormal uterine bleeding,intraperitoneal adhesions and infertility.This article discusses the preventive measures of PCSD from the following aspects:the choice of uterine incision,the technique of uterine suture,the choice of suture materials and the management of postoperative short-term complications.

Amniotic fluid embolism(AFE)is rare and the most catastrophic complication of pregnancy,and it is often life-threatening to pregnant women and fetus.AFE is not only a major cause of direct maternal mortality in developed countries,but also one of the top three main factors contributing to maternal mortality in China.Since caesarean section is one of the risk factors for AFE,we retrospectively reviewed articles and documents about AFE related to caesarean section in recent 10 years,and shared the opinions and experience in regard to diagnosis and prevention of AFE in caesarean section,especially the experience of multidisciplinary team work in the management of women with AFE,including the obsterics and anesthesia departments.

Uterine fistula after cesarean section mainly occurs in developing countries.With the development of social economy,the incidence of uterine fistula in China is gradually decreasing.However,in recent years,the incidence of placenta previa–accreta is increasing and the intraoperative injury is increasing.We describe the most common uterine fistula after cesarean section to provide reference and basis for its diagnosis and treatment.