The Stimulation To Induce Mothers Study (STIM)

The Stimulation To Induce Mothers (STIM) Study: A Parallel Group Randomized Controlled Trial

The investigators propose a parallel group randomized clinical trial of intrapartum nipple stimulation versus exogenous oxytocin infusion for nulliparous women undergoing induction of labor near term. The central hypothesis is that intrapartum nipple stimulation to induce labor increases spontaneous vaginal delivery, improves patient-centered outcomes such as childbirth satisfaction, labor agentry, and pain scores, and reduces adverse neonatal and maternal outcomes in nulliparous women. The investigators will pursue the following specific aims: 1) Assess the effectiveness of intrapartum nipple stimulation on the rate of spontaneous vaginal delivery in nulliparous women, 2) Breastfeeding as the sole source of nutrition at time of maternal hospital discharge (Primary Aims); 3) Maximal percent newborn weight loss during the birth hospitalization within 72 hours of life, 4) Determine the effect of intrapartum nipple stimulation on the rate of adverse maternal and neonatal outcomes, 5) Determine the impact of intrapartum nipple stimulation on patient-centered outcomes and 6) In a sub-cohort of women who are enrolled in the trial, investigators will measure the change in oxytocin concentration from baseline to time at which patient achieves a regular contraction pattern.

Study Overview

• Status: Recruiting
• Conditions: Labor Pain; Oxytocin; Induction of Labor Affected Fetus / Newborn; Physiologic Effects of Drugs
• Intervention / Treatment: Device: Electric breast pump; Drug: Exogenous oxytocin intravenous infusion without nipple stimulation.

Detailed Description

Primary Objectives

1. To determine whether intrapartum nipple stimulation therapy with or without synthetic oxytocin changes the likelihood of achieving a spontaneous vaginal delivery compared to receipt of synthetic oxytocin infusion without nipple stimulation to induce labor.
2. Breastfeeding as the sole source of nutrition at time of maternal hospital discharge

Secondary Objectives (if applicable)

The secondary objectives are as follows:

1. Determine whether intrapartum nipple stimulation therapy with or without synthetic oxytocin changes the likelihood of achieving a spontaneous vaginal delivery compared to receipt of synthetic oxytocin infusion without nipple stimulation to induce labor.
2. Determine if women who perform intrapartum nipple stimulation to induce labor have differences in other obstetric and maternal outcomes
3. Determine if women who perform intrapartum nipple stimulation report differences in pain scores during labor, labor agentry and satisfaction scores, postpartum depression scores, and breastfeeding success compared to women who receive only intrapartum exogenous oxytocin infusion.
4. Determine if women who perform intrapartum nipple stimulation to induce labor have similar fetal and neonatal outcomes compared to women who receive only intrapartum exogenous oxytocin infusion.
5. Maximal percent newborn weight loss during the birth hospitalization within 72 hours of life
6. At Yale, to measure the change in oxytocin concentration from baseline over the course of labor induction in patients undergoing induction of labor via intrapartum nipple stimulation versus continuous exogenous oxytocin infusion.
7. At Yale, to measure circulating plasma and urine concentrations of proteins, microRNA, and small molecules using unbiased "omics" approaches, comparing patients undergoing induction of labor via intrapartum nipple stimulation versus continuous exogenous oxytocin infusion, un-ripened/unlabored control patients, and patients in spontaneous labor.

• Study Type: Interventional
• Enrollment (Estimated): 988
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Moeun Son, MD, MSCI; Phone Number: (212) 746-2106; Email: mos7003@med.cornell.edu
• Study Contact Backup: Name: Molly McAdow, MD, PhD; Email: molly.mcadow@yale.edu

Study Locations

• United States
  • Connecticut
    • New Haven, Connecticut, United States, 06510
      • Recruiting
      • Yale New Haven Hospital
      • Contact: Moeun Son, MD, MSCI; Email: moeun.son@yale.edu
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Active, not recruiting
      • Northwestern Memorial Hospital
  • New York
    • New York, New York, United States, 10065
      • Recruiting
      • Weill Cornell Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Nulliparous
• Gestational age 36 0/7 weeks and greater at enrollment
• Singleton gestation
• Planned to undergo initiation of exogenous oxytocin infusion by their maternity care provider
• Spontaneous rupture of membranes or if membranes intact, modified Bishop score ≥5 and cervix dilated <6 cm within one hour of enrollment
• Ability to give informed consent

Exclusion Criteria:

• Unable to understand English or Spanish
• Prior use of exogenous oxytocin or attempt at nipple stimulation during the current pregnancy
• Presence of tachysystole (defined as more than 5 contractions in 10 minutes averaged over 30 minutes), recurrent variable or late fetal decelerations, and bradycardia in the prior 30 minutes before enrollment
• Non-vertex presenting fetus at time of enrollment
• Planned for cesarean delivery or contraindication to labor by institutional policy (e.g., placenta previa, vasa previa, active genital herpes infection, previous transmural myomectomy)
• Multi-fetal gestation (e.g., twins, triplets, and higher-order multiples)
• Intrauterine fetal death
• Major fetal anomaly suspected prenatally (defined as a fetal anomaly with anticipated neonatal intensive care unit admission)
• Suspected alloimmunization (given the increased likelihood for anticipated neonatal intensive care unit admission)
• Known severe fetal growth restriction (estimated fetal weight <3rd percentile) or abnormal umbilical artery Doppler studies (given the increased likelihood for anticipated neonatal intensive care unit admission)
• HIV infection (nipple stimulation is not encouraged given the recommendation for these mothers not to breastfeed)
• Participation in another interventional study that influences management of labor and delivery or perinatal morbidity or mortality
• History of mastectomy or other contraindication to use of electronic breast pump
• Known allergic reactions to components of the electronic breast pump or to synthetic oxytocin intravenous solution
• Significantly impaired consciousness or executive function (e.g., intubated or sedated)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intrapartum nipple stimulation; Participants randomized to the intrapartum nipple stimulation will use electric breast pump or stimulate by hand (intervention) to induce labor.	Device: Electric breast pump; Participants randomized to the intrapartum nipple stimulation will use electric breast pump or nipple stimulate by hand (if preferred) (intervention) to induce labor for at least 2 hours; Other Names: Medela Symphony pump
Active Comparator: Exogenous oxytocin intravenous infusion; Participants randomized to the standard care arm will use exogenous oxytocin intravenous infusion to induce labor.	Drug: Exogenous oxytocin intravenous infusion without nipple stimulation.; Participants randomized to the standard care arm will use exogenous oxytocin intravenous infusion to induce labor as current standard of care; Other Names: Pitocin intravenous infusion

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Spontaneous vaginal delivery	Spontaneous vaginal delivery will be defined as delivery that occurs without the use of forceps, vacuum, or cesarean	At delivery
Breastfeeding as the sole source of nutrition (BSSN)	Number of participants using breastfeeding as the sole source of nutrition (BSSN) at time of maternal discharge or 72 hours of life (whichever is sooner)	up to 72 hours following delivery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Operative vaginal delivery	Delivery with the assistance of forceps or vacuum, and indication	At delivery
Cesarean delivery	Delivery by cesarean section	At delivery
Labor induction duration	Time interval from randomization to delivery	At delivery
Neonatal Apgar score ≤3 at 5 minutes of life	The Neonatal Apgar score is scored from 0 to 10. A 5-minute Apgar score of 0-3 correlates with neonatal mortality in large population studies.	At 5 minutes after birth
Umbilical acidemia	Umbilical cord arterial pH <7.0 or base excess >12 mmol/L; or umbilical cord venous pH <7.0 or base excess >12 mmol/L if arterial blood sample not available	At delivery
Composite neonatal severe morbidity measure	Intrapartum fetal death or neonatal death; cardiorespiratory support within first 72 hours of life; neonatal encephalopathy; seizures; hypothermic treatment (cooling); sepsis; pneumonia; major birth injury; meconium aspiration syndrome; intracranial hemorrhage or subgaleal hemorrhage; or hypotension requiring pressor support	up to 28 days following delivery
Lactational mastitis	Subject-reported occurrence of lactational mastitis	After delivery to 12 weeks postpartum
Number of Participants with Postpartum hemorrhage	Cumulative blood loss of ≥1,000 mL within 24 hours after the birth process	From delivery to 24 hours postpartum
Number of Participants with Severe Postpartum hemorrhage	Transfusion; non-elective hysterectomy; use of ≥2 uterotonic medications other than oxytocin; other interventions such as uterine compression sutures, uterine artery ligation or embolization, hypogastric artery ligation, balloon tamponade	From delivery to 24 hours postpartum
Number of participants with suspected infection	Suspected intraamniotic infection, intrapartum chorioamnionitis, or postpartum endometritis (defined as maternal fever ≥38° Fahrenheit with planned or initiated administration of therapeutic antibiotics) after randomization and prior to delivery hospitalization discharge	3-7 days postpartum
Number of maternal deaths	Incidence of maternal death prior to, during, or post delivery	immediately prior to up to immediately post delivery
Maternal Intensive Care Unit admission	Any admission to the Intensive Care Unit after delivery and prior to delivery hospitalization discharge	3-7 days postpartum
Neonatal Intensive Care Unit admission	Any admission to the Neonatal Intensive Care Unit From birth to birth hospitalization discharge or 28 days after birth, whichever is earlier	up to 28 days following birth
Percent newborn weight loss	Maximal percent newborn weight loss in kilograms(kg)	At 72 hours of life or birth hospitalization discharge, whichever is earlier

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subject-reported pain during childbirth	Visual analog scale, scored with Likert scale from 0 (no pain) to 10 (worst pain)	At intervention start and than again 2 hours after intervention start
Subject-reported feelings of control during labor and childbirth	Labor Agentry Scale is a 29-item survey designed to assess expectations and experiences of personal control during childbirth (scores range from 29 to 203, with higher scores indicating greater perceived control during childbirth)	6-96 hours after delivery
Subject-reported depression score	Edinburgh Postnatal Depression Scale is a 10-item self report scored from 0 to 30; score >10 warrants additional clinical assessment for depression	4 to 12 weeks after delivery
Subject-reported satisfaction during labor and childbirth	Birth Satisfaction Scale-Revised (BSS-R) is a 10-item self-report valid and reliable measure (scores range from 0 to 40, 0 being the least satisfaction and 40 being the most satisfaction)	6-96 hours after delivery
Subject-reported breastfeeding success	Maternal Breastfeeding Evaluation Scale (MBES) is a 30-item using a 5-point Likert scale with higher scores reflecting more positive breastfeeding experiences.	4 to 12 weeks after delivery
Subject-reported ability to express and/or collect colostrum and/or breastmilk intrapartum	Participants ability to express and/or collect colostrum and/or breastmilk intrapartum	From randomization to hospital discharge, approximately 3-7 days
Subject-reported perception of milk supply	Subject-reported perception of milk supply using the validated Perception of Insufficient Milk Supply (PIMS). PIM is defined as a state in which a mother has or perceives that she has an inadequate supply of breast milk to meet her infant's needs. A perception of insufficient milk supply is associated with early discontinuation of breastfeeding.	2 weeks postpartum

Collaborators and Investigators

• Sponsor: Yale University
• Collaborators: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
• Investigators: Principal Investigator: Bethany Stetson, MD, Northwestern University; Principal Investigator: Moeun Son, MD, MSCI, Weill Medical College of Cornell University; Principal Investigator: Molly McAdow, MD, PhD, Yale University

Publications and helpful links

General Publications

• Tortal D, Shabanova V, Taylor S, Xu X, McAdow M, Stetson B, McCollum S, Sanchez E, Adjakple A, Leventhal J, Son M. Stimulation Therapy to Induce Mothers: Protocol for a Multicenter Randomized Controlled Trial. JMIR Res Protoc. 2024 Aug 29;13:e63463. doi: 10.2196/63463.

Study record dates

Study Major Dates

• Study Start (Actual): November 15, 2021
• Primary Completion (Estimated): November 1, 2028
• Study Completion (Estimated): March 1, 2029

Study Registration Dates

• First Submitted: September 20, 2021
• First Submitted That Met QC Criteria: October 14, 2021
• First Posted (Actual): October 15, 2021

Study Record Updates

• Last Update Posted (Actual): March 24, 2026
• Last Update Submitted That Met QC Criteria: March 19, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Labor Pain; Physiological Effects of Drugs; Reproductive Control Agents; Oxytocics; Oxytocin
• Other Study ID Numbers: 2000031338; 1R01HD111633-01 (U.S. NIH Grant/Contract); 231888-1 (Other Grant/Funding Number: Cornell University, Joan and Sanford I. Weill Medical College)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified data will be shared with academic researchers for secondary analyses or meta-analyses only after approval from the principal investigator and using an IRB-approved mechanism.
• IPD Sharing Time Frame: Data will become available after publication and will be available for 5 years.
• IPD Sharing Access Criteria: De-identified data will be shared with academic researchers for secondary analyses or meta-analyses only after approval from the principal investigator and using an IRB-approved mechanism.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No