Antibiotic Prophylaxis to Prevent Obesity-Related Induction Complications in Nulliparae at Term 2.0

Phase 2

Recruiting

• Conditions: Obesity in Pregnancy; Labor Complication
• Interventions: Drug: Placebo; Drug: Azithromycin

• Registration Number: NCT06488781
• Lead Sponsor: University of Oklahoma

Brief Summary

Obesity increases the risk of pregnancy complications, including puerperal infections and cesarean delivery, and risk rises with increasing body mass index (BMI). Since obese women are more likely to have comorbidities that would necessitate delivery prior to their due date (i.e. prior to 40 weeks gestation), and class III obesity specifically is an indication for delivery by 39 weeks, these patients have a high rate of labor induction. In nulliparous women from the general population (obese and non-obese), labor induction at 39 weeks (compared to expectant management) is associated with less maternal morbidity and a lower cesarean rate. Researchers previously conducted a pilot randomized placebo-controlled trial in obese, nulliparous women undergoing labor induction at term and found that the cesarean delivery rate was lower in women who received a prophylactic antibiotic regimen during labor compared with those who received the placebo. Researchers proposed multi-center trial aims to test this hypothesis in a large sample with adequate power to determine whether prophylactic antibiotics during labor are associated with a decrease in the rate of cesarean delivery in term, nulliparous, obese women. If the findings from the pilot trial are confirmed, this would represent a novel intervention to decrease the cesarean delivery rate in a subset of women at highest risk for cesarean-related complications.

Detailed Description

This is a multi-center randomized placebo-controlled trial in which nulliparous women with obesity who are undergoing induction of labor at term and not receiving IAP for GBS will be recruited (n=787). The participants will be randomized 1:1 to receive either prophylactic antibiotics during their labor induction (azithromycin 500 milligrams intravenously once and cefazolin 2 grams intravenously every 8 hours for up to three doses) or like-appearing placebos. The participants and their obstetrical providers will be blinded to the study intervention. The study will be conducted with an identical protocol at five study sites. Trained research nurses/assistants at each study site will consent and enroll participants, collect biospecimens, and collect demographic information and data on pregnancy and neonatal outcomes, and will convey this data to the primary site for analysis.

Researchers hypothesize that the group that receives the study drug regimen of prophylactic antibiotics during induction of labor will have a lower rate of cesarean delivery than the group that receives the placebo. They also hypothesize that the group that receives the study drug regimen will have a lower rate of puerperal infection than the placebo group.

Nulliparous women with obesity who are undergoing induction of labor at term will be eligible for participation in the study. Across all sites, 787 total subjects will be recruited.

Study Timeline

• Study First Submitted: 2024-05-28
• Study First Submitted QC: 2024-06-28
• Study First Posted: 2024-07-05
• Study Start: 2025-04-29
• Status Verified: 2025-07
• Last Update Submitted: 2025-07-15
• Last Update Posted: 2025-07-17
• Primary Completion: 2028-12
• Study Completion: 2028-12-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 787

Inclusion Criteria

• BMI ≥30
• No prior deliveries at or beyond 20 weeks gestation
• Undergoing induction of labor
• Gestational age 37 weeks or more
• Age 15-45
• Not receiving IAP for GBS prophylaxis

Exclusion Criteria

• Fetal death prior to labor induction
• Known fetal anomaly
• Multiple gestation
• Ruptured membranes for more than 12 hours
• Chorioamnionitis or other infection requiring antibiotics at the start of the labor induction
• Previous myometrial surgery
• Allergy to azithromycin or beta-lactam antibiotics

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Placebo	Placebos, similar in appearance, in place of azithromycin and cefazolin
Prophylactic antibiotics	Azithromycin	Azithromycin 500 milligrams intravenously once and cefazolin 2 grams intravenously every 8 hours for up to three doses

Primary Outcome Measures

Name	Time	Method
Rate of cesarean delivery	30 days postpartum	Determine whether a prophylactic antibiotic regimen during labor induction will decrease the rate of cesarean delivery in obese, nulliparous women undergoing induction of labor

Secondary Outcome Measures

Name	Time	Method
Maternal hospital stay	30 days postpartum	Length of maternal hospital stay
Neonate hospital stay	30 days postpartum	Length of neonatal hospital stay
Rate of postpartum hemorrhage	30 days postpartum	Rate of maternal postpartum hemorrhage
Rate of blood transfusion	30 days postpartum	Rate of maternal blood transfusions
Rate of intensive care unit admission	30 days postpartum	Maternal admission into intensive care unit
Rate of hospital readmission	30 days postpartum	Maternal hospital readmission after delivery
Rate of indications for cesarean delivery	30 days postpartum	Rate of indications for a cesarean delivery
Rate of chorioamnionitis development	30 days postpartum	Defined clinically by fever and maternal and fetal signs such as tachycardia and uterine tenderness
Rate of cesarean wound infection	30 days postpartum	Rate of maternal would infection from cesarean section
Rate of endometritis	30 days postpartum	Maternal development of endometritis
Rate of necrotizing enterocolitis	30 days postpartum	Infant necrotizing enterocolitis
Periventricular leukomalacia	30 days postpartum	Development of periventricular leukomalacia in infant as seen by ultrasound
Rate of intraventricular hemorrhage	30 days postpartum	Intraventricular hemorrhage grade III or higher
Neonatal death	30 days postpartum	Death of neonate
Rate of NICU admission	30 days postpartum	Neonatal intensive care unit (NICU) admission
APGAR score	30 days postpartum	5-minute APGAR score \<4 (neonate)
Rate of respiratory distress syndrome	30 days postpartum	Development of infant respiratory distress syndrome
Rate of sepsis	30 days postpartum	Infant sepsis (either suspected or confirmed)

Trial Locations

Locations (1)

University of Oklahoma Health Sciences Center; 🇺🇸 Oklahoma City, Oklahoma, United States