Cervical incompetence occurs when the cervix fails to maintain its normal morphology and function during second-trimester, leading to recurrent second-trimester miscarriages or preterm births. To standardize and guide the clinical diagnosis and treatment of cervical insufficiency in China, the Perinatal Medicine Branch of the Chinese Medical Association and the Obstetrics Group of the Chinese Society of Obstetrics and Gynecology developed this consensus by referencing related research evidence and so on. This consensus provides evidence-based analysis and recommendations on key clinical issues including the diagnosis of cervical incompetence, indications for cervical cerclage, surgical techniques, timing of intervention, perioperative management, and adjunctive therapies, offering evidence-based guidance for obstetric clinical practice.Practice guideline registration:International Practice Guidelines Registry and Transparency Platform (PREPARE-2024CN1155)

Abstract. Objective:. To investigate gestational age–specific variations in cervical length (CL) and evaluate the predictive ability of CL for preterm delivery (PTD) across different trimesters. Methods:. This retrospective longitudinal study included a total of 8659 women who delivered singleton live births between June 1, 2022, and December 31, 2024, at Peking University First Hospital. Associations between CL measured at ≤ 19+6, 20–24+6, and 28–33+6 gestational weeks and PTD were evaluated using receiver operating characteristic curve analysis and log-rank tests. Results:. CL showed substantial variability across gestational ages, with pronounced shortening observed during 28–33+6 weeks. Significant differences in CL distribution between women with PTD and those with term delivery emerged as early as 20–24+6 weeks. The predictive value of CL for PTD increased with advancing gestational age. Optimal CL thresholds for predicting PTD ≤ 34+6 weeks were 28 mm, 15 mm, and 10 mm at ≤ 19+6, 20–24+6, and 28–33+6 weeks, respectively, while corresponding thresholds for PTD < 37 weeks were 28 mm, 26 mm, and 10 mm. Women with CL below these cut-offs had significantly lower probabilities of term delivery. The 26-mm threshold at mid-gestation (20–24+6 weeks) closely aligned with the conventional 25-mm definition of short cervix, supporting the validity of the minimum P approach. The consistent 10-mm threshold in late gestation suggests that lower diagnostic cut-offs after 28 weeks may be required to guide clinical management. Conclusion:. CL progressively decreases with increasing gestational age and has emerged as a more potent predictor of PTD after 20 weeks of gestation. A short cervix in late pregnancy may be more appropriately defined as < 10 mm at 28–33+6 gestational weeks.

Background/Objectives: Amnioreduction prior to emergency cervical cerclage (ECC) has been proposed as a method to relieve the tension of the protruding amniotic membrane, thereby facilitating its intact retraction back into the uterine cavity. However, the effect of this procedure on pregnancy outcomes remains unclear. This study aims to evaluate the effect of amnioreduction on pregnancy outcomes in patients who received ECC during the second trimester. Methods: We conducted a retrospective analysis of the characteristics and pregnancy outcomes of patients who underwent ECC across four institutions between 1 July 2021 and 31 December 2024. Pregnancies were classified into the amnioreduction group and the non-amnioreduction group based on whether amnioreduction was performed prior to the ECC. The gestational age (GA) at delivery was the primary outcome measure. A multivariate linear regression model was employed to identify factors associated with GA at delivery. Additionally, a propensity score matching model was constructed for sensitivity analysis. A subgroup analysis was also conducted for pregnancies with cervical dilation ≥ 4 cm to evaluate the effect of amnioreduction in this specific subpopulation. Results: A total of 406 pregnancies were analyzed, and the results indicated no significant differences between the amnioreduction group and the non-amnioreduction group regarding GA at delivery (30.4 (25.7, 35.9) vs. 31.2 (26.0, 37.0) weeks, p = 0.655) or pregnancy latency (days from cerclage to delivery: 49.0 (15.0, 87.5) vs. 57.0 (18.0, 92.3) days, p = 0.397). The rates of preterm birth at <28 weeks (37.0% vs. 37.2%, p = 0.969), <32 weeks (54.6% vs. 52.3%, p = 0.684), <34 weeks (64.8% vs. 60.7%, p = 0.455), and <37 weeks (77.8% vs. 73.8%, p = 0.417) of gestation, as well as the rate of preterm premature rupture of membranes (26.9% vs. 22.5%, p = 0.360), were comparable between the two groups. No differences were observed in the neonatal birth weight or 5 min Apgar score between the groups. After balancing baseline characteristics using propensity score matching, all outcome measures remained similar between the two groups. Subgroup analysis of pregnancies with painless cervical dilation ≥ 4 cm also revealed no significant differences in any outcome measures between those who received amnioreduction and those who did not prior to ECC. Conclusions: Amnioreduction performed prior to ECC was not associated with adverse pregnancy outcomes based on the endpoints assessed in this cohort. Because procedure-specific complications were not systematically recorded, prospective studies collecting procedure-related safety data are required before amnioreduction can be definitively recommended.

During pregnancy, hyperfiltration and other factors are hypothesized to contribute to the progression of kidney disease in women with Alport syndrome. To evaluate the status of kidney disease, clinical data from mothers with Alport syndrome in China and Europe over the pregnancy were analyzed. This retrospective observational study collected data to evaluate proteinuria, kidney function and Alport stage prior to, during, and after pregnancy, respectively. A total of 74 women were enrolled, 82

Short cervix is a risk factor for preterm birth. Currently, both international and domestic studies about progesterone's effectiveness are limited to pregnant women at 18-24 weeks gestation. However, multiple studies indicated that cervical length was associated with preterm birth even before 32 weeks of gestation. Therefore, this study expanded the gestational week range to investigate whether progesterone can reduce the rate of preterm birth in singleton pregnant women with a short cervix at 18-32 weeks gestation. Pregnant women who underwent prenatal examination at Peking University First Hospital from January 2016 to August 2020 were prospectively followed. A total of 132 asymptomatic singleton pregnant women at 18-32 weeks gestation with a cervical length <25 mm were ultimately enrolled. According to the method of treatment, the participants were divided into progesterone group (80 patients) and control group (52 patients). The rate of preterm birth (PTB) at different stages was compared between two groups. (1) There was no significant difference in the total preterm birth rate (18.8% vs. 21.2%, RR 0.886[0.442-1.777], p = 0.734). (2) Stratified analysis found that, for pregnant women at <24 weeks gestation, there was a significant difference in the rate of PTB at <32 weeks (2.8% vs. 33.3%, p = 0.021). For women at 24-28weeks gestation, significant difference was not found in the rate of PTB at <37 weeks gestation (25% vs. 42.9%, RR = 0.583[0.186-1.831], p = 0.682), neither for women at after 28 weeks(12.5% vs. 11.1%,1.12[0.27-4.59], p = 1). (3) Vaginal progesterone was not associated with low birth weight (13.8% vs. 19.2%, p = 0.4), or preterm birth-related complications such as respiratory distress syndrome (3.8% vs. 7.7%, p = 0.555), aspiration pneumonia (22.5% vs. 19.2%, p = 0.653) and sepsis (2.5% vs. 7.7%, p = 0.331). For pregnant women with a short cervix at 18-24 weeks gestation, the rate of preterm birth before 32 weeks could be significantly reduced. For women with a short cervix at 24-28 weeks gestation, the rate of preterm birth could be reduced, while there was no significant effect for pregnant women. Further studies with a larger sample size and randomized controlled researches are needed.

In January 2023, the Society of Obstetricians and Gynaecologists of Canada (SOGC) released the guidelines "Cervical Ripening and Induction of Labour" based on the latest research results and evidence-based evidence, which are divided into three parts: General, Cervical Ripening and Induction of Labour, detailing the indications and methods of cervical ripening and induction of labor. This article highlights the main update points in the guideline. The SOGC Induction Guideline emphasizes the individualization of induction and the importance of respecting patients' choices and providing humane care. The guideline also recommends to confirm gestational age according to the ultrasound examination at 8-12 weeks and inducing labor for pregnant women aged 40 and above at or after 39 weeks. In terms of cervical ripening, both balloon catheters and prostaglandin preparations are effective, with balloon catheters being suitable for women with scarred uterus who require vaginal delivery. Balloon catheters and prostaglandin E 2 suppositories can be used for outpatient cervical ripening. Misoprostol and prostaglandin E 2 preparations can be used for both cervical ripening and labor induction. Low-dose oral misoprostol is safe and effective, while misoprostol solution is easier to administer accurately.If cervical ripening is prolonged, the process of cervical ripening can be interrupted if the mother and fetus are safe.

BackgroundThe most common disorder of the intracellular cobalamin metabolism pathway is the combined methylmalonic acidemia and homocysteinemia, cblC type (cblC). There is a variation in its clinical spectrum ranging from severe neonatal-onset forms that are highly fatal to later-onset forms which are milder. In this study, the first case of an asymptomatic Chinese woman with a defect in congenital cobalamin (cblC type) metabolism at prenatal diagnosis due to elevated homocysteine level is identified.Case presentationThe proband, a male child born to a 29-year-old G1P0 mother, admitted to local hospital with feeding disorder, intellectual disability, seizures, microcephaly, as well as heterophthalmos. The level of the urine methylmalonic was elevated. Equally found were increased blood propionylcarnitine (C3) and propionylcarnitine/free carnitine ratio (C3/C0) and decreased methionine levels. The plasma total homocysteine level was elevated at 101.04 μmol/L (normal < 15 μmol/L). The clinical diagnosis of combined methylmalonic acidemia and homocysteinemia was supported. Four years later, the mother of the boy married again and came to us for prenatal diagnosis exactly 15 weeks after her last menstrual period. Subsequently, there is an increase in the amniotic fluid methylmalonate. The level of the amniotic fluid total homocysteine was marginally high. A considerably elevated amniotic fluid C3 was equally observed. In addition, there is a respective significant increase in the plasma and urine total homocysteine at 31.96 and 39.35 μmol/L. After the sequencing of MMACHC genes, it is found that the boy, a proband carried a homozygous mutation of the MMACHC at c.658_660delAAG. While the boy's mother, she carries two mutations in MMACHC: c.658_660delAAG and c.617G>A. The fetus is a carrier of the MMACHC gene. Following the administration of routine treatment, the mother remained symptom-free in the course of pregnancy, and she gave birth to a healthy boy.ConclusionVariable and nonspecific symptoms characterized the cblC type of methylmalonic acidemia combined with homocysteinemia. Both biochemical assays and mutation analysis are recommended as crucial complementary techniques.

With the advances in fetal medicine, there will be more cases of congenital hypothyroidism (CH) diagnosed in the fetal period. However, there is no consensus on the management protocol. We present a successful case of conservatively managed fetal goitrous hypothyroidism due to compound heterozygous TG mutations. Goiter was observed in a fetus at 23 weeks of gestation. Because there was no evidence of transplacental passage of antithyroid antibody and drugs, iodine overload, and iodine deficiency, the fetus was highly suspected to have CH. Considering the potential risks of amniocentesis/cordocentesis, and lack of available parenteral levothyroxine in China, the fetus was closely monitored thereafter. A male neonate was delivered vaginally without complications at 39 weeks of gestation. We verified severe hypothyroidism in the infant and immediately initiated levothyroxine therapy. His growth and mental development were normal at the age of 8 month. Whole-exome sequencing showed that the neonate had two compound heterozygous mutations in the TG gene. We also performed a literature review of the prognosis of postnatal treatment of CH due to TG mutations and the result showed that postnatal treatment of CH due to TG mutations has a favorable prognosis. However, further prospective studies are warranted to verify this conclusion.

目的:探讨双胎妊娠紧急子宫颈环扎术(CC)的临床疗效.方法:收集2004 年1 月至2021年12 月于北京大学第一医院就诊并分娩的双胎妊娠孕16～27 +6周宫口开大1～4cm行紧急CC的30 例孕妇的临床资料,依据CC的孕周分为<24 周组(19 例)和≥24 周组(11 例).比较两组的CC疗效,以是否获得活产儿分为成功组(23 例)和失败组(7 例),分析影响CC分娩结局的相关因素.结果:①30 例双胎妊娠紧急CC后的分娩孕周29.5±5.2 周,围产儿死亡率25.0%,延长孕周6.8±4.4 周.②孕周≥24 周组孕妇的CC孕周(24.7±0.8 周 vs.21.7±1.6 周)、分娩孕周(31.6±2.8周vs.28.3±6.0 周)及活产率(100.0%vs.63.2%)明显高于<24 周组,差异有统计学意义(P<0.05).③多因素Logistics回归分析示,术前超声检查宫腔内絮状回声、术后白细胞计数(WBC)≥10×109/L是双胎妊娠紧急CC失败的独立危险因素(OR>1,P<0.05),CC孕周≥24 周是保护性因素(OR<1,P<0.05).结论:双胎妊娠孕周≥24 周后行紧急CC仍有临床价值,必要时双胎妊娠行紧急CC可以在孕24～27 +周进行.CC孕周<24 周、术前超声检查提示宫腔内絮状回声、术后WBC≥10×109/L者双胎妊娠紧急CC失败的风险升高.

应激性心肌病(SCM),又称Tako-Tsubo综合征,其发病机制尚不明确,容易漏诊、误诊.本文报告了 2例双胎妊娠剖宫产术后并发应激性心肌病病例.两例患者分别因"胎儿窘迫"、"妊娠期重度胆汁淤积症"于孕34～35周行剖宫产术,术后1～4 h因血压升高检测心肌酶,发现心肌酶升高,后完善相关检查,诊断为急性SCM.经无创呼吸机辅助通气、白蛋白输注、降压、维持出入量负平衡、抗感染、抗凝、改善心肌重构等治疗,分别于手术7 d和15 d后出院.孕期及产后并发SCM的病例少见,剖宫产及双胎妊娠期可能是其危险因素.本文分享两例SCM的治疗过程以及预后情况,为临床类似病例的诊治提供经验.

Objective:To investigate the changes in cervical length (CL) after history- indicated cerclage through serial ultrasound measurements and the predictive value of short cervix (CL≤2.5 cm) before 24 gestational weeks after cerclage in preterm delivery before 34 weeks.Methods:In this retrospective study, clinical data of 145 singleton pregnancies with history-indicated McDonald cerclage at Peking University First Hospital from January 2010 to June 2021 were collected. CL was measured through transvaginal ultrasound and recorded during the perioperative period and at ≥20-24, ≥24-28, and ≥28-32 weeks of gestation. The participants were divided into ≥34 weeks group ( n=118) and <34 weeks group ( n=27) based on the gestational age at delivery. Chi-square or independent sample t test was applied for comparison between the two groups. The relationship between CL after cerclage and preterm birth before 34 week in the two groups was analyzed using multivariate logistic regression analysis. The risk of preterm birth in women with short cervix at 20-24 weeks of gestation after cerclage was estimated. The receiver operator characteristic curve was adopted for predicting the diagnostic value of postoperative CL on pregnancy outcomes. Results:(1) Among the 145 cases, 106 cases (73.1%) had term delivery, 27 cases (18.6%) had premature delivery before 34 weeks, among which seven cases (4.8%) had late miscarriage before 28 weeks (including two cases with survived viable infants). The overall live birth rate was 96.6% (140/145). (2) In the ≥34 weeks group, CL at ≥20-24, ≥24-28, and ≥28-32 weeks of gestation were significantly longer than those in the <34 weeks group [(3.35±0.73) vs (2.39±1.03) cm, t=5.69, P=0.008; (3.14±0.75) vs (2.14±1.10) cm, t=5.65, P=0.007; (2.91±0.85) vs (1.79±1.09) cm, t=5.84, P=0.005]. (3) Multivariate logistic regression analysis showed that CL at ≥20-24, ≥24-28, and ≥28-32 weeks after cerclage were the influencing factors of preterm birth before 34 weeks [ OR (95% CI)=0.885 (0.837-0.935), 0.886 (0.837-0.937), 0.890 (0.842-0.940), respectively, all P<0.001]. (4) The area under the curve of CL at ≥20-24, ≥24-28, and ≥28-32 weeks were 0.747, 0.734, and 0.799 for predicting delivery before 34 weeks, with the sensitivity of 60.0%, 60.0%, and 80.0%, and the specificity of 87.5%, 91.3%, and 76.9%, respectively. (5) At ≥20-24 weeks after cervical cerclage, women with a short cervix accounted for 17.2% (25/145), who were 12.7 times more likely to have premature birth before 34 weeks than those with a CL over 2.5 cm ( OR=12.7, 95% CI: 4.58-35.40, P<0.001). Conclusions:Among pregnant women with history-indicated cervical cerclage, CL after cerclage at ≥20-24, ≥24-28, and ≥28-32 weeks of gestation have predictive values for pregnancy outcomes. A short cervix at ≥20-24 weeks of pregnancy after cerclage could predict premature birth before 34 weeks.

妊娠中期超声检查所提示的羊膜腔絮状物（AFS）是一种高回声物质，是宫内感染发生炎性反应后，由于重力作用沉积于子宫颈内口处的聚集性现象。AFS往往提示羊膜腔内感染，与晚期流产、早产关系密切。一旦出现AFS合并子宫颈管缩短，应行羊膜腔穿刺术明确感染性质，同时可积极行抗炎治疗，定期超声监测子宫颈长度以及AFS的变化情况。本文综述AFS的性质、在晚期流产和早产中的意义、抗生素治疗的有效性，从而为妊娠中期超声检查提示AFS孕妇的治疗以及管理提供新的临床思路。

子宫颈机能不全(cervical insufficiency,CI)主要由于子宫颈的先天性发育异常或后天损伤性的功能缺陷所致,临床特点为孕中期无痛性子宫颈扩张,羊膜囊膨出和(或)胎膜破裂,最终导致晚期流产和早产.CI占所有孕妇的0.5％～1％[1].子宫颈环扎术(cervical cerclage,CC)是治疗CI的主要方法,研究证实有明确的疗效[1].本文主要阐述CI的诊断和孕期经阴道环扎的时机.

目的 通过对未足月胎膜早破(preterm premature rupture of membrane,PPROM)病例进行临床资料分析,研究能否通过患者的临床指标进行组织学绒毛膜羊膜炎(histologic chorioamnionitis,HCA)的预测.方法 回顾性分析2010年1月至2016年12月在北京大学第一医院分娩并获得产后胎盘病理结果的单胎PPROM孕妇388例,根据产后胎盘病理结果分为HCA组和非HCA组,其中HCA组168例,非HCA组220例,统计其临床资料;记录孕妇入院及分娩前的白细胞(white blood cell,WBC)计数、中性粒细胞(neutrophil,NE)计数、中性粒细胞百分比(neutrophil％,NE％)、淋巴细胞计数、C反应蛋白(C-reactive protein,CRP)结果,计算中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR),通过ROC曲线的绘制进一步探讨不同指标对HCA的预测价值,并结合临床指标的评分系统对PPROM孕周＜34周发生HCA进行预测.结果 ①HCA组所占比例43.3％(168/388),HCA组平均PPROM孕周(33+4周)、分娩孕周(33+6周)低于非HCA组(35+1周,35+2周)(P＜0.05);②病史资料的研究显示HCA组体外受精胚胎移植术+宫腔操作术史(11.9％)高于非HCA组(5.5％);③HCA组产前孕妇发热(17.3％)、产褥感染(6.0％)高于非HCA组(9.1％,0)(P＜0.05);④ HCA 组与非 HCA 组相比,孕妇分娩前血 CRP(11mg/Lvs 5 mg/L)、WBC(13.1×109/L vs 10.6×109/L)、NE(10.7×109/L vs 8.4 x 109/L)、NE％(80.9％vs 78.4％)、NLR(6.9 vs 5.3)比较,有统计学差异(P＜0.05);⑤PPROM＜34周分娩前血CRP的ROC曲线下面积为0.806,其对预测HCA的敏感性为65.6％;⑥PPROM＜34周临床评分≥3分对预测HCA的敏感性为87.0％,特异性为93.8％,阳性预测值为95.2％,阴性预测值为83.3％.结论 母体分娩前血CRP是预测＜34周胎膜早破发生HCA的最佳血清学因子,结合临床指标的评分系统对于预测＜34周PPROM孕妇中发生HCA具有较高的敏感性和特异性.

Background Methylmalonic aciduria (MMA), a rare inherited disorder, is the most common organic aciduria in China, and prenatal diagnosis has contributed to its prevention. However, the prenatal diagnosis of MMA using cultured amniocytes or chorionic villi to detect gene mutations is exclusively applicable to families with a definite genetic diagnosis. To evaluate the reliability of mass spectrometry assays for the prenatal diagnosis of MMA, we conducted a retrospective study of our 10 years' experience. Materials and methods This retrospective compare study reviewed the medical records for maternal and fetuses data for 287 mothers with a family history of MMA from June 2010 to December 2020. Methylmalonate and propionylcarnitine in cell-free amniotic fluid were measured using a stable isotope dilution method (GC/MS) and MS/MS-based method (LC/MS/MS). Total homocysteine (tHcy) was measured by fluorescence polarization immunoassay. Depending on the presence of disease-causing gene mutations in probands, gene studies on amniocytes from 222 pregnant women were performed. Results For 222 fetuses of the families with definite genetic diagnosis, gene analyses were performed using cultured amniocytes. 52 fetuses were affected by MMA, whereas 170 were "unaffected". For GC/MS and LC/MS/MS, the specificity was 96.5% and 95.9%, sensitivity was 71.2% and 84.6%, respectively. The positive and negative predictive values were 86.0% and 91.6% and 86.3% and 95.3%, respectively. Propionylcarnitine/butyrylcarnitine ratio showed the highest accuracy and could thus serve as a sensitive indicator to identify those at a risk for MMA. When GC/MS and LC/MS/MS were performed in parallel, the specificity was 92.5% and sensitivity was 95.6%. When evaluating tHcy, the positive and negative predictive values were 95.0% and 96.1%, respectively. In 65 fetuses without family genetic diagnosis, 11 were finally confirmed to have MMA and 54 were "unaffected" by amniotic fluid biochemical assays. The 54 children showed normal urine organic acids and healthy development after birth. Conclusions Amniotic fluid biochemical assays using GC/MS and LC/MS/MS in parallel increased the accuracy of prenatal diagnosis of MMA. Propionylcarnitine is a more reliable marker than methylmalonic acid in amniotic fluid. Further, tHcy is recommended for the prenatal diagnosis of combined MMA and homocysteinemia.

子宫肌瘤是育龄女性最常见的生殖系统良性肿瘤.妊娠合并子宫肌瘤发生率为0.1％ ～3.9％,随着婚育年龄后延,其发病率有所上升[1] ,约10％ ～30％患者在妊娠期、分娩期及产褥期出现并发症[2].自1994年Lucas等[3]报道妊娠期腹腔镜子宫肌瘤剔除术( laparoscopic myomectomy during pregnancy,LMdP)以来,在条件具备的前提下,逐渐替代开腹手术成为孕期处理有症状子宫肌瘤的一种手段.本文对该术式的历史与现状、围术期问题等进展进行综述,以期对临床工作有所帮助.

Objective: To evaluate the ability of cervical length (CL) at 28-32 weeks of gestation to predict spontaneous preterm delivery and preterm premature rupture of membranes (PPROM).Methods: It was a retrospective cohort study that vaginal ultrasonography at approximately 28-32 weeks of gestation was performed in 14,953 women between 17-49 years old with singleton pregnancies who delivered after 28 weeks of gestation at the Peking University First Hospital from June 2008 to December 2012. The pregnancy outcomes were followed and the relationship between the CL and preterm delivery or PPROM was assessed. The relative risk was calculated to assess group differences in the likelihood of an event occurring.Results: The overall prevalence of preterm delivery was 5.7% (858/14,953); the incidence for therapeutic preterm delivery was 2.1% (318/14,953), for spontaneous preterm delivery was 0.9% (133/14,953), and for PPROM was 2.7% (407/14,953). Excluding the 318 women who had therapeutic preterm delivery, the relative risk of preterm delivery for women with a CL between 25 mm and <30 mm, between 15 mm and <25 mm, and <15 mm was 3.7, 9.3, and 30.2, respectively. The sensitivity, specificity, and positive and negative predictive values of CL ≤25 mm at 28-32 weeks of gestation as the cut-off value for predicting preterm delivery were 19.8%, 97.5%, 23.4%, and 96.9%, respectively. For preterm delivery before 35 weeks of gestation, the sensitivity, specificity, and positive and negative predictive values of a CL ≤ 25 mm at 28-32 weeks of gestation as the cut-off value were 30.0%, 97.2%, 11.8%, and 99.1%, respectively. In addition, women with PPROM (n = 407) had significantly shorter CL (31.9 ± 7.4) mm at 28-32 weeks of gestation compared that of women without PPROM (34.0 ± 8.3) mm. The incidence of PPROM in women with a CL ≤25 mm at 28-32 weeks of gestation (19.4%, 79/407) was significantly lower than that for women with a CL >25 mm (80.6%, 328/407,P < 0.05).Conclusion: CL at 28-32 weeks of gestation can predict spontaneous preterm delivery, and is valuable for predicting PPROM.

We review the safety and efficacy of antenatal corticosteroid (ACS) in different pregnant populations at risk of preterm birth. According to the current evidence, attention should be paid to the following aspects: Pregnant women with fetal growth restriction exposuring to ACS are more likely to deliver a low birth weight infant, repeated administration without indications is not recommended; Though ACS is beneficial to pregnant women with premature rupture of membranes complicated by chorionic amniotic inflammation, it is not recommended to use uterine inhibitors for completing the treatment of ACS. For those with acute chorionic amniotic inflammation, pregnancy should be terminated as soon as possible; For twin/multiple pregnancies, the ACS therapy is the same as for singletons, but the efficacy is controversial.