Sleep Disordered Breathing, Obesity and Pregnancy Study (SOAP) (SOAP)
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT02086448 |
Recruitment Status :
Completed
First Posted : March 13, 2014
Results First Posted : March 8, 2022
Last Update Posted : March 22, 2023
|
- Study Details
- Tabular View
- Study Results
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Obese Pregnancy Sleep Disordered Breathing | Device: CPAP Device: sham-CPAP Other: Sleep hygiene | Not Applicable |
Emerging data support a link between sleep disordered breathing (SDB) and adverse pregnancy outcomes, particularly preeclampsia. Furthermore, SDB, which is characterized by intermittent nocturnal hypoxia-reoxygenation as well as sleep disruption, results in endothelial dysfunction and metabolic dysregulation, the same biological pathways that have been associated with adverse pregnancy outcomes. Obesity is a well-known risk factor for both adverse pregnancy outcomes and SDB, and has been associated with the same aforementioned biological aberrations. Therefore, obesity complicates the definition of a causal relationship between SDB and pregnancy outcomes. While some classic cardiovascular risk factors (prehypertension) are certainly relevant in pregnancy, there are also well-established risk factors that are unique to pregnancy (uterine vascular stiffness, placental angiogenic factors). The interplay between SDB, obesity and these unique cardiovascular risk factors remains undefined, and this proposal aims to address this knowledge gap. Without this data, our ability to understand how we can mitigate these risks through the use of therapeutic interventions for SDB, such as CPAP (continuous positive airway pressure), is compromised. To further address this knowledge gap, we will make use of the placenta's ability to accumulate evidence of damage over time and provide a record of maternal vascular health throughout gestation. Numerous placental lesions deriving from maternal vascular disease have been identified and can be readily detected on placental pathology. These lesions can provide a measure of the severity of hypoxic stress experienced by the fetus during gestation.
The investigators' central hypothesis is that SDB is an effect modifier that increases maternal cardiovascular risk and placental hypoxic injury in obese pregnant women, and that CPAP treatment during pregnancy will result in an improved cardiovascular risk and placental profile. To test this hypothesis the investigaotrs will identify a cohort of obese women both with and without SDB. The investigators will examine SDB's impact on maternal vascular stiffness (uterine artery Doppler), angiogenesis (pregnancy specific angiogenic factors e.g., sFLT-1) and metabolism (insulin resistance) across pregnancy (Aim 1). The investigators will perform a randomized controlled trial of autotitrating- CPAP verses sham-CPAP in pregnancy to examine the impact of CPAP treatment during pregnancy on cardiovascular risk (Aim 2) and will explore the interplay between SDB, CPAP and evidence of maternal vascular disease and chronic fetal hypoxia by evaluating the placental profile of obese women with and without SDB (Aim 3).
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 242 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | Sleep Disordered Breathing, Obesity and Pregnancy Study (SOAP) |
Study Start Date : | September 2014 |
Actual Primary Completion Date : | December 2021 |
Actual Study Completion Date : | February 2022 |
Arm | Intervention/treatment |
---|---|
No Intervention: Obese, SDB negative
No intervention, observational comparison group
|
|
Active Comparator: Obese, SDB postive, CPAP
Therapeutic CPAP
|
Device: CPAP
CPAP is a device that has a mask worn over the nose that is attached to a device that provides positive airway pressure. CPAP is worn while sleeping, it splints open the airway and prevents apneas (cessation of breathing) and hypopneas (reduced airflow while breathing).
Other Name: Continuous Positive Airway Pressure |
Sham Comparator: Obese, SDB postive, sham-CPAP
Sham (non-therapeutic) CPAP
|
Device: sham-CPAP |
Obese, SDB postive, sleep hygiene
Sleep hygiene information and local sleep resources
|
Other: Sleep hygiene
Information about sleep apnea and healthy sleep. Information about local sleep resources |
- Uterine Artery Doppler Mean Pulsatility Index -by Ultrasound [ Time Frame: early pregnancy (14-16 weeks gestation) ]The uterine artery was located using color doppler imaging by placing the ultrasound probe in the right or left iliac fossa in the sagittal plane. The uterine artery was then identified where it crosses the external iliac artery. Doppler waveform was obtained using a sampling gate encompassing the width of the main uterine artery at an angle of insonation of <30 degrees if possible. The PI was calculated using the formula: maximum-minimum velocity/mean velocity.
- Soluble FMS-like Tyrosine Kinase 1 (sFlt-1)/ Placental Growth Factor (PlGF) Ratio-blood Measurement [ Time Frame: early pregnancy (14-16 weeks gestation) ]sFlt-1 is a splice variant of vascular endothelial growth receptor (VEGF) with antiangiogenic properties that is upregulated in preeclampsia. PlGF is an angiogenic cytokine that is highly expressed in the placenta. Low levels have been associated with preeclampsia.
- Homeostasis Model Assessment of Insulin Resistance (HOMA-IR)-Blood Measurement of Glucose and Insulin [ Time Frame: early pregnancy (14-16 weeks gestation) ]Insulin resistance was calculated using the homeostatic model assessment for insulin resistance (HOMA-IR, fasting insulin (µU/mL) x fasting glucose (mmol/L) /22.5)
- Uterine Artery Doppler Mean Pulsatility Index -by Ultrasound [ Time Frame: late pregnancy (28-32 weeks gestation) ]The uterine artery was located using color doppler imaging by placing the ultrasound probe in the right or left iliac fossa in the sagittal plane. The uterine artery was then identified where it crosses the external iliac artery. Doppler waveform was obtained using a sampling gate encompassing the width of the main uterine artery at an angle of insonation of <30 degrees if possible. The PI was calculated using the formula: maximum-minimum velocity/mean velocity.
- Soluble FMS-like Tyrosine Kinase 1 (sFlt-1)/ Placental Growth Factor (PlGF) Ratio-blood Measurement [ Time Frame: late pregnancy (28-32 weeks gestation) ]sFlt-1 is a splice variant of vascular endothelial growth receptor (VEGF) with antiangiogenic properties that is upregulated in preeclampsia. PlGF is an angiogenic cytokine that is highly expressed in the placenta. Low levels have been associated with preeclampsia.
- Homeostasis Model Assessment of Insulin Resistance (HOMA-IR)-Blood Measurement of Glucose and Insulin [ Time Frame: late pregnancy (28-32 weeks gestation) ]Insulin resistance was calculated using the homeostatic model assessment for insulin resistance (HOMA-IR, fasting insulin (µU/mL) x fasting glucose (mmol/L) /22.5)
- Placental Histology and Immunohistochemistry [ Time Frame: After delivery (expected 37-40 weeks gestation) ]placental histology and immunohistochemistry
- Mean Arterial Blood Pressure (mmHg) Angiogenic Domain [ Time Frame: early pregnancy (14-16 weeks gestation) ]
- Pregnancy Outcome Data [ Time Frame: At time of delivery (expected 37-40 weeks gestation) ]Preeclampsia, Gestational diabetes, Gestational age at delivery, Indication for delivery, Birthweight, Cord gases
- Mean Arterial Blood Pressure (mmHg) Angiogenic Domain [ Time Frame: late pregnancy (28-32 weeks gestation) ]
- Soluble Endoglin (sEng ,pg/mL)-Blood Measurement [ Time Frame: early pregnancy (14-16 weeks gestation) ]Endoglin is a coreceptor for transforming growth factor beta-1 and beta-3 expressed on syncytiotrophoblasts
- Soluble Endoglin (sEng , pg/mL)-Blood Measurement [ Time Frame: late pregnancy (28-32 weeks gestation) ]Endoglin is a coreceptor for transforming growth factor beta-1 and beta-3 expressed on syncytiotrophoblasts

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- women between 14 0/7 and 20 6/7 weeks gestation at the time of their initial PSG assessment.
- Pregnancy and current BMI >=30
- Self-reported frequent snoring (>=3x/week over past month) or self-reported non-snorer.
Exclusion Criteria:
- diagnosis of pregestational diabetes.
- self-report a history of sleep apena and who are using or were receommended by a physican to use a PAP device already
- twins

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02086448
United States, Pennsylvania | |
Magee-Womens Hospital of the UPMC | |
Pittsburgh, Pennsylvania, United States, 15213 |
Principal Investigator: | Francesca Facco, MD | University of Pittsburgh |
Documents provided by Francesca Facco, MD, University of Pittsburgh:
Responsible Party: | Francesca Facco, MD, Assistant Professor, University of Pittsburgh |
ClinicalTrials.gov Identifier: | NCT02086448 |
Other Study ID Numbers: |
PRO13080159 R01HL120354 ( U.S. NIH Grant/Contract ) K12HD043441 ( U.S. NIH Grant/Contract ) |
First Posted: | March 13, 2014 Key Record Dates |
Results First Posted: | March 8, 2022 |
Last Update Posted: | March 22, 2023 |
Last Verified: | February 2023 |
Respiratory Aspiration Sleep Apnea Syndromes Respiration Disorders Respiratory Tract Diseases Pathologic Processes |
Apnea Sleep Disorders, Intrinsic Dyssomnias Sleep Wake Disorders Nervous System Diseases |