Inducing labor at 39 weeks versus later induction or waiting in low‑risk pregnancies in China.

Labor Induction in Low-risk Women at 39 Weeks of Gestation: A Randomized Trial in China

This study will test whether inducing labor at 39 weeks, compared with inducing at 41 weeks or waiting, reduces cesarean deliveries and improves outcomes for low‑risk pregnant women in China.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 1074 (estimated)
• Ages: 18 Years and up
• Sex: Female
• Sponsor: Women's Hospital School Of Medicine Zhejiang University (other)
• Locations: 1 site (Hangzhou, Zhejiang)
• Trial ID: NCT07082530 on ClinicalTrials.gov

What this trial studies

This randomized trial enrolls low‑risk pregnant women at 38 weeks 4 days to 39 weeks 3 days and randomly assigns them to induction at 39 weeks, induction at 41 weeks, or expectant management. The primary outcome is cesarean delivery rate, with collection of other maternal and neonatal outcomes to compare safety and benefits across groups. Cord blood samples will undergo multi‑omics analyses (including metabolomics and proteomics) to identify biological markers associated with outcomes. The trial is led by the Women's Hospital, School of Medicine, Zhejiang University at its Hangzhou site.

Who should consider this trial

Good fit: Ideal candidates are low‑risk pregnant women aged 18 or older with a singleton pregnancy (or twins reduced to singleton before 14 weeks), reliable dating, desire and eligibility for vaginal birth, and who are between 38 weeks 4 days and 39 weeks 3 days at enrollment.

Not a fit: Women with planned cesarean delivery, contraindications to induction or vaginal birth, abnormal placentation, ruptured membranes at enrollment, or unreliable gestational dating are unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, it could identify a timing for induction that lowers cesarean rates and improves maternal and newborn health in the Chinese population.

How similar studies have performed: A large U.S. trial (ARRIVE) found that elective induction at 39 weeks reduced cesarean rates, while similar international trials are ongoing and Chinese‑specific evidence is currently lacking.

Eligibility criteria

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.

Where this trial is running

Hangzhou, Zhejiang

• Women's Hospital School of Medicine Zhejiang University — Hangzhou, Zhejiang, China (RECRUITING)

Study contacts

• Principal investigator: Dan Zhang, Ph. D. — Key Laboratory of Reproductive Genetics, Women's Hospital, Zhejiang University School of Medicine
• Study coordinator: Huajing Gao, MD Candidate

Conditions: Cesarean Delivery