Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:The clinical data of prenatal stillbirth were analyzed in order to increase the understand-ing of the causes of stillbirth.Methods:Prenatal stillbirth cases that terminated pregnancy in Nanjing Drum Tower Hospital,Affiliated Hospital of Medical School,Nanjing University from January 2018 to December 2022 were col-lected,and the distribution characteristics of clinical data and the stillbirth causes were analyzed.The causes of death were classified according to the standards developed by the Stillbirth Collaborative Research Network(SCRN)in the United States,and they were divided into clear cause-of-death group and unknown cause-of-death group.The different characteristics of the two groups were compared and analyzed.Results:There were 210 ca-ses of prenatal stillbirth during the study period,and 104 cases met the inclusion criteria.Among them,33 cases(31.7%)had autopsy results,39 cases(37.5%)had genetic results,and 75 cases(72.1%)had placental pathol-ogy.According to the classification of SCRN standard,55 cases(52.9%)were probably related to the cause of death,33 cases(31.7%)were classified as possible,13 cases(12.5%)were probably unrelated,and 3 cases(2.9%)could not be attributed to the cause of death,that is,84.6%(88 cases)in the clear cause of death group and 15.4%(16 cases)in the unknown cause of death group.The rate of placental pathological examination in the clear cause of death group was significantly higher than that in the unknown cause of death group(78.4%).In the classification of causes of death,placental pathological changes accounted for the largest proportion,account-ing for 26.9%(28 cases),followed by pregnancy complications accounting for 25.0%(26 cases),and 15.4%of the cases were still unexplained.Conclusions:Placental pathology is of great significance for clarifying the cause of stillbirth.It is feasible to use SCRN to classify the etiology of stillbirth.Pathological placental conditions account for a relatively high proportion in the classification of stillbirth causes.It is recommended that each case of stillbirth placenta should undergo pathological examination.

Objective:To analyze the effectiveness and interobserver agreement of the Parer five-tier, the National Institute of Child Health and Human Development (NICHD) three-tier, and the International Federation of Gynecology and Obstetrics (FIGO) three-tier electronic fetal monitoring (EFM) systems in identification of neonatal acidosis during labor.Methods:This retrospective study was conducted on full-term singleton cephalic deliveries with neonatal acidosis (umbilical artery blood gas pH≤7.1) and normal newborns (umbilical artery blood gas pH≥7.2) in the Nanjing Drum Tower Hospital, Nanjing University Medical School from January to December 2020. EFM tracings during the last 30-60 min before delivery were collected. Four obstetricians independently described the features of randomly sorted and coded EFM tracings. Another obstetrician categorized these tracings using the NICHD three-tier, FIGO three-tier, and Parer five-tier evaluation systems based on the features. All researchers were masked to the clinical characteristics and maternal and neonatal outcomes. The sensitivity and specificity for identifying neonatal acidosis, as well as the interobserver agreement, were analyzed for all three systems. Independent sample t-test, Chi-square (or Fisher's exact test) and Mann-Whitney U tests were used for statistical analysis. Inter-group comparisons of sensitivity and specificity between the three evaluation systems were assessed using McNemar's test. The Kappa statistic was used to analyze interobserver agreement. Results:This study included a total of 3 558 cases. After propensity score matching, there were 44 cases of neonatal acidosis and 78 control cases. There were no significant differences in parity, gestational weeks, modes of delivery, placental abruption, or analgesia rates between the two groups. The rates of instrumental vaginal delivery and neonatal intensive care unit (NICU) admission in the acidosis group were significantly higher than those in the control group [15.8% (7/44) vs. 2.6% (2/78), χ2=8.45, P=0.003; 31.8% (14/44) vs. 12.8% (10/78), χ2=8.45, P=0.004], while the umbilical artery blood pH and mean base excess were lower in the acidosis group than in the control group [7.04±0.07 vs. 7.30±0.05, t=4.98; (－12.40±3.32) vs. (－5.64±1.95) mmol/L, t=13.61; both P<0.001]. (2) Using the NICHD three-tier system, 95.5% (42/44) of the acidosis cases and 89.7% (70/78) of the control cases were classified as having category Ⅱ EFM tracings, indicating potential fetal acid-base imbalance; category Ⅲ EFM tracings were only observed in 4.5% (2/44) of the cases in the acidosis group. With the FIGO three-tier system, 81.8% (36/44) of the acidosis cases were categorized as having "pathological" tracings, and with the Parer five-tier system, 86.4% (38/44) of the acidosis cases were correctly classified into the "orange or red" risk zones that indicated acid-base imbalance. Among the control cases, there were 28.2% (22/78) with EFM tracings of "normal patterns" categorized by the FIGO three-tier system, and 41.0% (32/78) classified into the "green or blue" risk zones by the Parer five-tier system, which indicated good fetal conditions. None of the acidosis cases were misdiagnosed as being normal by the Parer five-tier system. (3) Compared with the NICHD three-tier system, both the FIGO three-tier and the Parer five-tier systems showed increased diagnostic sensitivity [4.5% (1.2%- 14.5%) vs. 81.8% (66.8%-89.4%) and 86.4% (71.8%-92.4%)], but decreased specificity [100.0% (95.3%- 100.0%) vs. 87.2% (78.0%-92.9%) and 84.6% (75.0%-91.0%)]. There was no statistically significant difference in the sensitivity or specificity between the FIGO three-tier and Parer five-tier systems for identifying neonatal acidosis ( P=0.727 and 0.791). (4) When reading the tracings of control cases, the total agreement rate for the NICHD three-tier system by different observers was as high as 94.2%, while the total agreement rates for the FIGO three-tier and Parer five-tier systems were 69.7% and 67.7%, respectively. In the interpretation of EFHR tracings for acidosis cases, the interobserver agreement for the Parer five-tier system was excellent [Kappa (95% CI): 0.87 (0.79-0.95)], while both the NICHD three-tier and FIGO three-tier systems showed good agreement [Kappa (95% CI): 0.77 (0.66-0.88) and 0.72 (0.60-0.84)]. Conclusions:The Parer five-tier and the FIGO three-tier systems have higher sensitivity in identifying neonatal acidosis than the NICHD three-tier system, and the Parer five-tier system achieves a higher negative predictive value and a greater agreement in the interpretation of pathological EFM patterns.

Objective:To evaluate the role of improved management procedures in placenta accreta spectrum disorders (PAS) and its impact on maternal and infant outcomes.Methods:This retrospective study involved 164 pregnant women who were diagnosed with PAS complicated with placenta previa and delivered at Nanjing Drum Tower Hospital, Nanjing University Medical School from January 2019 to December 2022. All subjects were allocated to pre-improvement group (January 2019 to December 2020, n=96) and post-improvement group (January 2021 to December 2022, n=68). The management was improved in the following five aspects: (1) The time for scheduled delivery was postponed to 37 weeks from 34-36 weeks;(2) Intraoperative cell salvage was encouraged despite autologous blood donation during pregnancy;(3) Original surgical incision was utilized instead of mid-longitudinal incision in the lower abdomen to reduce operative trauma; (4) A lower segment incision of the uterus was not prohibited based on pre-operative PAS classification and intra-operative situation to enter the uterine cavity, even through the placenta instead of pass-by;(5) The interface between lower uterine segment and bladder was dissected before instead of after the baby was born and uterine blood supply was stopped by tourniquet or Scharr forceps. Statistical methods such as t-test, Chi-square test or Fisher exact probability method were used to compare the difference in maternal and infant outcomes between the two groups. Results:After the improvement, the delivery rate beyond 37 weeks decreased significantly [83.3% (80/96) vs 69.1% (47/68), χ 2=4.60, P=0.038]. There was no significant difference in the distribution of elective, subemergency and emergency surgeries before and after the improvement ( χ 2=0.36, P=0.834). Compared to the pre-improvement group, the proportion of women who underwent cesarean section through previous abdominal incisions increased significantly [74.0% (71/96) vs 91.1% (64/68), χ 2=11.11, P=0.001] in the post-improvement group, while the proportion of application of abdominal longitudinal incision and classical cesarean section decreased significantly [84.3% (81/96) vs 57.3% (39/68), χ 2=14.81, P<0.001; 83.3% (80/96) vs 61.8% (42/68), χ 2=9.72, P=0.003]. No significant difference was found between the two groups in terms of the transfusion rate of allogeneic red blood cell, platelet and other blood components, pre-discharge hemoglobin level, subtotal hysterectomy rate, bladder injury, thrombus event, the admission rate of intensive care unit and unplanned reoperation rate (all P>0.05). The incidence of admission in neonatal intensive care unit (NICU) and necrotizing enterocolitis decreased significantly after improvement [24.7% (24/97) vs 11.8% (8/68), χ 2=4.31, P=0.038; 4.1% (4/97) vs 0.0% (0/68), χ 2=58.06, P<0.001]. The incidence of respiratory distress syndrome, mechanical ventilation, and neonatal septicemia also decreased, but without statistical difference. Conclusions:After adopting a series of improvement measures, such as delaying planned delivery to 37 weeks of gestation, individualized cesarean section plan, and changing the method of obtaining autoblood, the number of premature infants and the NICU admission rate decreased significantly without increasing the risk of maternal complications and emergency operation. Furthermore, the incidence of adverse events such as maternal organ injury, unplanned reoperation, and re-admission remains at a low level. Therefore, this improved management is feasible.