Steps to Extend Latency in Preterm Prelabor Rupture of Membranes (STEP)

The goal of this quasi-experimental study is to determine if there are improved outcomes for patients with preterm prelabor rupture of membranes (PPROM) who walk daily. The main question it aims to answer is:

- Are patients with PPROM who walk at least 3500 steps per day more likely to stay pregnant longer than those who walk less?

Participants will be encouraged to walk ≥3500 steps per day from the time of diagnosis until delivery and their daily step counts will be recorded. Researchers will compare those who actually walk ≥3500 steps per day to those who walk less.

Study Overview

• Status: Not yet recruiting
• Conditions: Preterm Prelabor Rupture of Membranes (PPROM)
• Intervention / Treatment: Behavioral: Ambulate

Detailed Description

The primary objective of this study is to determine if there is increased latency to delivery for patients with PPROM who ambulate ≥3500 steps per day compared to those who ambulate less. The investigators have chosen a goal of 3500 steps as this equates to approximately 30 minutes of moderate-intensity walking, and ACOG endorses the US Department of Health and Human Services Physical Activity Guidelines which recommend at least 150 minutes of moderate intensity aerobic activity per week during pregnancy.

The secondary objective of this study is to determine whether there is a lower risk of adverse maternal and neonatal outcomes for patients with PPROM who ambulate ≥3500 steps per day compared to those who ambulate less. Maternal adverse outcomes that will be assessed include rate of intra-amniotic infection, placental abruption, umbilical cord prolapse, cesarean delivery for non-reassuring fetal heart tracing, and thromboembolic events. Neonatal adverse outcomes that will be assessed include gestational age at delivery, birth weight, APGAR score at 5 minutes, requirement for NICU admission, length of stay, and neonatal death. The investigators will also assess the average steps per day for each participant and type of smartphone (i.e. Android vs iPhone).

Inclusion criteria include patients admitted to Cedars-Sinai with PPROM between the gestational ages of 24w0d and 33w6d who have planned inpatient management of at least 7 days, a phone capable of monitoring and sharing step count, and a singleton or dichorionic twin gestation. Exclusion criteria include patients with malpresentation (specifically, transverse, footling breech, or funic presentation), active preterm labor, or active vaginal bleeding.

This is a quasi-experimental study. All patients will be encouraged to ambulate ≥3500 steps per day. Patients will then be categorized into two cohorts: those who ambulated ≥3500 steps per day and those who ambulated <3500 steps per day. Outcomes will be compared between the two cohorts.

The duration of the study for each patient is the length of time from admission to delivery.

The study will be conducted at one site only, Cedars-Sinai.

At the time of study recruitment, patients will be given information about exercise in pregnancy and encouraged to ambulate at least 3500 steps per day. They will also be asked to share their daily step count via their smartphone health app with a member of the research team. All other antepartum, intrapartum, and postpartum care will be standard and/or per the primary obstetrician's discretion. After hospital discharge, a member of the research team will record the patient's daily step count and extract demographic information as well as obstetric and neonatal outcomes from the EMR.

Our primary outcome is the mean number of days of latency to delivery, and the investigators will use a Welch's t-test to assess the difference between our two study groups. The investigators will then use a multivariable linear regression analysis to account for potentially confounding variables.

For our secondary outcomes, the investigators will assess time from diagnosis to delivery using a log-rank test followed by a cox regression analysis. Additionally, maternal demographic and obstetric outcomes as well as neonatal outcomes will be compared using chi square and t-test for categorical and continuous variables, respectively.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Glenda Marshall, MD; Phone Number: 4243244193; Email: glenda.marshall@cshs.org
• Study Contact Backup: Name: Gabriela Dellapiana, MD; Phone Number: 3104237417

Study Locations

• United States
  • California
    • Los Angeles, California, United States, 90048
      • Cedars-Sinai Medical Center
      • Contact: Glenda Marshall, MD; Phone Number: 4243244193; Email: glenda.marshall@cshs.org
      • Contact: Gabriela Dellapiana, MD; Phone Number: 3104237417

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: Female

Description

Inclusion Criteria:

• Planned inpatient expectant management of ≥7 days
• Phone capable of monitoring and sharing step count
• Singleton or dichorionic twin gestation

Exclusion Criteria:

• Any records flagged "break the glass" or "research opt out"
• Transverse, footling breech, or funic presentations
• Active preterm labor
• Active vaginal bleeding

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Encouraged to Ambulate; All patients will be encouraged to ambulate ≥3500 steps per day	Behavioral: Ambulate; Ambulate ≥3500 steps per day

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Days of latency until delivery	From hospital admission to delivery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants who experience a thromboembolic event		From admission until maternal hospital discharge, an average of 1-4 days after delivery
Number of participants who experience a postpartum hemorrhage	Postpartum hemorrhage is defined as EBL/QBL >= 1000mL	From admission until maternal hospital discharge, an average of 1-4 days after delivery
Number of participants who experience maternal sepsis		From admission until maternal hospital discharge, an average of 1-4 days after delivery
Number of participants who are admitted to the Intensive Care Unit (ICU)		From admission until maternal hospital discharge, an average of 1-4 days after delivery
Days of postpartum length of stay		From admission until maternal hospital discharge, an average of 1-4 days after delivery
Mode of delivery	Vaginal delivery versus cesarean section	Day of delivery
Estimated or quantitative delivery blood loss		From admission until maternal hospital discharge, an average of 1-4 days after delivery
Number of participants who experience an intraamniotic infection		From admission until maternal hospital discharge, an average of 1-4 days after delivery
Number of patients who experience a placental abruption		From admission until delivery
Number of patients who experience an umbilical cord prolapse		From admission until delivery
Spontaneous versus induced labor		From admission until delivery
Indication for cesarean delivery	Only for patients who deliver via cesarean delivery	Day of delivery
Gestational age at delivery		Day of delivery
Neonatal birth weight		Day of delivery
APGAR score at 5 minutes of life	APGAR score (Appearance, Pulse, Grimace, Activity, and Respiration) is on a scale from 0-10. Lower scores indicate that infants are more likely to require resuscitation.	5 minutes of life on day of delivery
Umbilical cord blood gas values	Arterial pH, CO2, and base excess	Day of delivery
Number of neonates who require Neonatal Intensive Care Unit (NICU) admission		From delivery until day of neonatal hospital discharge, varies based on gestational age at delivery
Neonatal length of hospital stay		From delivery until day of neonatal hospital discharge, varies based on gestational age at delivery
Number of participants who receive at least one course of antenatal corticosteroids		From admission until delivery
Number of participants who receive antenatal magnesium sulfate		From admission until delivery
Number of neonatal deaths		From admission until day of neonatal hospital discharge (or death when applicable), varies based on gestational age at delivery

Collaborators and Investigators

• Sponsor: Cedars-Sinai Medical Center
• Investigators: Principal Investigator: Gabriela Dellapiana, MD, Cedars-Sinai Medical Center

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2027

Study Registration Dates

• First Submitted: October 19, 2026
• First Submitted That Met QC Criteria: November 6, 2026
• First Posted (Actual): November 13, 2026

Study Record Updates

• Last Update Posted (Actual): November 13, 2026
• Last Update Submitted That Met QC Criteria: November 6, 2026
• Last Verified: November 1, 2026

More Information

Terms related to this study

• Keywords: Physical Activity; Exercise; Pregnancy; Walking; Preterm Birth; PPROM
• Additional Relevant MeSH Terms: Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Obstetric Labor, Premature; Obstetric Labor Complications; Pregnancy Complications; Behavior; Premature Birth; Motor Activity; Preterm Premature Rupture of the Membranes
• Other Study ID Numbers: STUDY00004892

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

IPD Plan Description

To protect patient confidentiality

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No