Cesarean Delivery
Conditions
Brief summary
The investigators are committed to identifying the optimal timing of delivery for low-risk pregnancies. While current guidelines typically recommend induction at 41 weeks, emerging evidence suggests that elective induction at 39 weeks may lead to improved maternal and neonatal outcomes. The U.S.-based ARRIVE trial demonstrated that induction at 39 weeks significantly reduced cesarean delivery rates compared to expectant management, and a similar randomized controlled trial (French-ARRIVE) is ongoing in France. However, population-specific evidence for the Chinese population remains lacking. This study is designed to establish a prospective cohort of low-risk pregnant women in China, comparing the effects of induction at 39 weeks, induction at 41 weeks, and expectant management on cesarean section rates and other maternal and neonatal outcomes. In addition, multi-omics technologies will be employed to analyze cord blood samples-including metabolomics and proteomics-to identify early biomarkers potentially associated with long-term child health. The study will begin with a pilot phase to assess feasibility and inform operational strategies for large-scale implementation. The ultimate goal of this project is to generate evidence tailored to the Chinese population to support more individualized decision-making, improve clinical outcomes, and enhance maternal and neonatal safety.
Interventions
PROCEDURELabor Induction at 39 Weeks
Labor induction at 39 weeks 0 days to 39 weeks 4 days
PROCEDUREExpectant management
Expectant management until spontaneous labor or induction at 41 weeks.
Sponsors
Women's Hospital School Of Medicine Zhejiang University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
1. Age ≥18 years. 2. Singleton pregnancy or twin pregnancy reduced to singleton before 14 weeks. 3. Gestational age between 38 weeks 4 days or 39 weeks 3 days at randomization. 4. Eligible for vaginal delivery with a desire for vaginal birth. 5. Reliable gestational age determination. 6. Maternal and fetal conditions assessed as favorable by at least two senior obstetricians, with no indications requiring delivery before 41 weeks. 7. Ability to understand study information and provide informed consent.
Exclusion criteria
1. First-trimester ultrasound estimate \>13 weeks 6 days. 2. Planned induction before 41 weeks. 3. Planned cesarean delivery or contraindications to vaginal delivery. 4. Already delivered, in labor, or ruptured membranes at enrollment. 5. Placenta previa, vasa previa, placenta accreta, or placental abruption. 6. Contraindications to induction (e.g., cervical cancer, history of uterine rupture, genital tract malformations, abnormal fetal position, cord prolapse). 7. Active vaginal bleeding exceeding spotting. 8. History of cesarean delivery or uterine/cervical surgery. 9. Cervical cerclage during this pregnancy. 10. Maternal conditions not suitable for expectant management beyond 39 weeks (e.g., pregestational diabetes, gestational diabetes requiring insulin, hypertensive disorders, intrahepatic cholestasis of pregnancy). 11. Fetal conditions not suitable for expectant management beyond 39 weeks (e.g., fetal death, major anomalies, growth restriction, macrosomia, anemia, oligohydramnios, polyhydramnios). 12. Maternal infections or positive screenings for sexually transmitted pathogens or group B Streptococcus. 13. Planned delivery at a non-study facility. 14. Participation in another intervention study affecting delivery management.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of cesarean section | Delivery day | The proportion of deliveries completed by cesarean section |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Chorioamnionitis | Delivery day | Incidence of chorioamnionitis, defined as a clinical diagnosis before delivery as: maternal body temperature rises (\>38°C) with 2 or more of the following symptoms: 1. Maternal tachycardia (\>100 beats/min); 2. Fetal tachycardia (\>160 beats/min) 3. Uterine tenderness and irritability 4. Purulent or malodorous amniotic fluid or vaginal discharge 5. Maternal leukocytosis (white blood cell count \> 15000/mm3) |
| Third-or fourth-degree perineal laceration | Delivery day | The incidence of third-or fourth-degree perineal laceration |
| Composite incidence of severe neonatal morbidity and perinatal mortality | Hospital discharge (Day 2-3) | The composite incidence of any of the following: 1. Antepartum, intrapartum, or neonatal death 2. Intubation, continuous positive airway pressure (CPAP) or high-flow nasal cannula (HFNC) for ventilation or cardiorespiratory support within first 72 hours 3. Apgar ≤ 3 at 5 minutes 4. Neonatal encephalopathy 5. Seizures 6. Sepsis (presence of a clinically ill infant in whom systemic infection is suspected with a positive blood, cerebral spinal fluid (CSF), or catheterized/suprapubic urine culture; or, in the absence of positive cultures, clinical evidence of cardiovascular collapse or an unequivocal X-ray confirming infection). 7. Pneumonia confirmed by X-ray or positive blood culture. 8. Meconium aspiration syndrome 9. Birth trauma (bone fractures, brachial plexus palsy, other neurologic injury, retinal hemorrhage, facial nerve injury) 10. Intracranial hemorrhage or subgaleal hemorrhage 11. Hypotension requiring pressor support |
| Emergency Cesarean Rate | Delivery day | Cesarean delivery performed immediately or shortly after clinical decision due to imminent threat to the life of the mother or fetus |
| Category 1 Emergency Cesarean Rate | Delivery day | Cesarean performed within approximately 30 minutes due to immediate life-threatening conditions (e.g., uterine rupture, severe fetal distress) |
| Category 2 Emergency Cesarean Rate | Delivery day | Cesarean performed within 60-75 minutes due to urgent but not immediately life-threatening indications (e.g., progressive fetal distress, labor arrest) |
| Elective Cesarean Rate | Delivery day | Planned cesarean performed at or after 39 weeks in the absence of emergency conditions, meeting all of the following: 1. Surgery scheduled ≥24 hours before onset of labor; 2. No spontaneous contractions or rupture of membranes; 3. Clear medical indications (e.g., placenta previa, breech presentation) or maternal request. |
| Operative Vaginal Delivery | Delivery day | The rate of vaginal deliveries assisted with instruments such as forceps or vacuum. |
| Postpartum hemorrhage | Hospital discharge (Day 2-3) | Refer to the ARRIVE cohort, defined as any of the following situations: 1. Transfusion 2. Non-elective hysterectomy 3. Use of two or more uterotonics other than oxytocin 4. Other surgical interventions such as uterine compression sutures, uterine artery ligation, embolization and hypogastric ligation, balloon tamponade 5. Curettage |
| Postpartum infection | Hospital discharge (Day 2-3) | Refer to the ARRIVE cohort, defined as any of the following situations: 1. Clinical diagnosis of endometritis 2. Wound reopened for hematoma, seroma, infection or other reasons 3. Cellulitis requiring antibiotics 4. Pneumonia 5. Pyelonephritis 6. Bacteremia unknown source 7. Septic pelvic thrombosis |
| ICU admission | Hospital discharge (Day 2-3) | The proportion of admission to the ICU |
| Maternal death | Hospital discharge (Day 2-3) | The incidence of maternal death |
| Preeclampsia/gestational hypertension | Hospital discharge (Day 2-3) | The incidence of preeclampsia or gestational hypertension diagnosed during labor |
| Maternal venous thromboembolism | Hospital discharge (Day 2-3) | Deep vein thrombosis or pulmonary embolism |
| Maternal pain | Hospital discharge (Day 2-3) | Median patient-reported pain outcomes with a 10-point Likert scale |
| Birth weight | Delivery day | The mean birth weight |
| Female gender | Delivery day | The proportion of female offspring in terms of physiological gender |
| Macrosomia | Delivery day | Birth weight \> 4000g |
| Incidence of large for gestational age | Delivery day | According to the infant's gender and gestational age, the birth weight exceeds the 90th percentile of infants of the same gestational age |
| Incidence of small for gestational age | Delivery day | According to the infant's gender and gestational age, the birth weight is less than the 10th percentile of infants of the same gestational age |
| Apgar scores at 5 min | Delivery day | Apgar score at 5 minutes after birth |
| Neonatal acidosis | Delivery day | The incidence of neonatal acidosis defined as umbilical artery blood pH \< 7.10 |
| Shoulder dystocia | Delivery day | The incidence of shoulder dystocia |
| Hyperbilirubinemia | Hospital discharge (Day 2-3) | The incidence of hyperbilirubinemia requiring phototherapy or exchange transfusion |
| Transfusion of blood products or blood | Hospital discharge (Day 2-3) | The incidence of neonatal transfusion of blood products or blood |
| Hypoglycemia incidence | Hospital discharge (Day 2-3) | The incidence of hypoglycemia (blood glucose \< 35mg/L) requiring intravenous treatment |
| Neonatal intensive care unit (NICU) admission | Hospital discharge (Day 2-3) | The incidence of admission to the NICU lasting more than 48 hours |
| Physical measurement indicators | 6 weeks and 6 months | Infant weight, length, head circumference, chest circumference, sitting height, upper arm circumference, subcutaneous fat, height-chest circumference index, crown-rump length/length |
| Growth balance indicators | 6 weeks and 6 months | Weight-for-length, length-for-age, weight-for-age z scores of infants, calculated using the World Health Organization (WHO) tool, WHO Anthro Survey Analyser |
| Growth retardation | 6 weeks and 6 months | Height standard deviation for age \< mean-2S or percentile method \< P3 |
| Abnormal neurological examination | 6 weeks and 6 months | The proportion of abnormal results in neurological examinations (hearing development, nerve reflexes) |
| Scores of Bayley Scales of Infant and Toddler Development (Bayley-4) | 6 weeks and 6 months | Total score, cognitive scale score, language scale score, motor scale score, social-emotional scale score, adaptive behavior scale score |
| Scores of Ages & Stages Questionnaires®, Third Edition (ASQ-3) | 6 weeks and 6 months | Total score, communication domain score, gross motor domain score, fine motor domain score, problem-solving domain score, personal-social domain score |
| Incidence of allergic diseases | 6 weeks and 6 months | Allergic diseases diagnosed by neonatologists, including cow's milk allergy, allergic rhinitis, eczema/allergic dermatitis, asthma, wheezing and other allergic disorders |
| Time from randomization to delivery | Delivery day | Median time from randomization to birth of the fetus, measured in hours |
| Use of epidural analgesia | Delivery day | Rate of epidural analgesia use |
| Maternal length of hospital stays | Hospital discharge (Day 2-3) | Median maternal hospital stays, measured in hours |
| Neonatal length of hospital stays | Hospital discharge (Day 2-3) | Median neonatal hospital stays, measured in hours |
| Pre-insurance hospitalization cost | Hospital discharge (Day 2-3) | Total hospitalization cost during delivery, before insurance reimbursement |
| Gestational Age at Delivery | Delivery day | Expressed in weeks and decimal days (e.g., 39 weeks + 5 days = 39.7 weeks) |
| Out-of-pocket hospitalization cost | Hospital discharge (Day 2-3) | Out-of-pocket cost incurred during delivery hospitalization |
Countries
China
Contacts
CONTACTHuajing Gao, MD Candidate
PRINCIPAL_INVESTIGATORDan Zhang, Ph. D.
Key Laboratory of Reproductive Genetics, Women's Hospital, Zhejiang University School of Medicine
Outcome results
None listed