for females ages 18 years and up (full criteria)
study started
completion around
Principal Investigator
by Tamara Grisales (ucla)



This study is designed to evaluate the safety and effectiveness of the Materna Prep Device in reducing pelvic muscle injuries during vaginal delivery.

Subjects are randomized to Materna Prep Device or Standard of Care without use of the Materna Prep Device

Intervention with the Materna Prep Device is expected to be a one-time use of approximately 30-90 minutes during the 1st stage of labor.

Subject participation in the study is targeted to be 12 months from the time of the use of the device during delivery.

Official Title

A Randomized, Controlled Study to Evaluate the Safety and Effectiveness of the Materna Prep Device to Pre-stretch the Vaginal Canal and Pelvic Floor Tissues in Preparation for Vaginal Delivery


Vaginal delivery is a major risk factor for pelvic floor dysfunction. Clinical aspects of pelvic floor dysfunction include pelvic organ prolapse, sexual dysfunction, and fecal and urinary incontinence. Trauma to the pelvic structures occurs as the fetal head passes through the vaginal canal, especially with acute distension at the time of crowning - the exiting of the fetal head.

The Materna Prep Device is a single-use, semi-automated dilator used during the first phase of labor in order to prepare the vaginal canal for vaginal delivery. By slowly pre-stretching the vagina and surrounding pelvic tissues during labor, the device is essentially dictating the strain rate of the tissue during labor. In previous feasibility studies, the elastic recovery of the tissue has been shown to be on the order of several hours, allowing the benefits of pre-stretching the vagina and surrounding pelvic tissues to last throughout labor. The device is intended to be removed prior to the initiation of the second stage of labor, for delivery to occur unobstructed.

The target patient population for this study is nulliparous women entering the first phase of labor and scheduled for vaginal delivery with an epidural.


Vaginal Delivery, Pelvic Organ Prolapse, Pelvic Floor Health, levator ani muscle injury, Pelvic Muscle Injury, Vaginal Delivery, Complications, Childbirth, prevention, Prolapse, Materna Prep Device


You can join if…

Open to females ages 18 years and up

Criteria for inclusion

  1. Subject is scheduled for vaginal birth.
  2. Subject is gestating a single fetus.
  3. Subject is nulliparous, or had a previous pregnancy terminated within 24 weeks gestation.
  4. Subject is able and willing to comply with the protocol required follow-up visits.
  5. Subject is able and willing to provide written informed consent prior to enrollment.
  6. In the opinion of the Investigator, the subject has sufficient mental capacity to understand the informed consent form (ICF), comply with the protocol requirements, and provide clinically relevant and reliable feedback regarding their experience with the device.
  7. Subject receives epidural anesthesia during labor prior to enrollment.
  8. Subject is 18 years of age or older at time of consent.

You CAN'T join if...

Criteria for exclusion

  1. Subject has high likelihood of less than 1 hour of potential device dilation time after she arrives at the hospital.
  2. Subject is planning or requires a Caesarean-section prior to randomization.
  3. Subject begins labor with less than 36 weeks gestation.
  4. Subject has a neurological disorder that could cause pelvic floor dysfunction, such as multiple sclerosis or spinal cord injury.
  5. Subject has a collagen-associated disorder that affects tissue elasticity, such as scleroderma or Ehlers-Danlos syndrome.
  6. Subject has a localized (genital tract) or systemic infection.
  7. Subject has a medical history which could lead to pelvic floor dysfunction, such as prior pelvic fractures, pelvic soft tissue injuries, or vaginal surgery.
  8. Subject has any general health condition or systemic disease that may represent, in the opinion of the Investigator, a potential increased risk associated with device use or pregnancy.
  9. Subject has placenta previa or vasa previa.
  10. Subject has known significant chromosomal or structural fetal anomalies.
  11. Subject has a category 2 and/or 3 fetal tracing that is unresolved.
  12. Subject is observed to have friable, denuded, or markedly edematous vaginal tissue during the course of labor.


  • University of California Los Angeles accepting new patients
    Los Angeles California 90095 United States
  • El Camino Hospital in progress, not accepting new patients
    Mountain View California 94040 United States
  • Baylor College of Medicine accepting new patients
    Houston Texas 77030 United States

Lead Scientist at University of California Health

  • Tamara Grisales (ucla)
    HS Associate Clinical Professor, Obstetrics and Gynecology, Medicine. Authored (or co-authored) 11 research publications


accepting new patients
Start Date
Completion Date
Materna Medical
Study Type
Expecting 450 study participants
Last Updated