Biomarkers of Uterine Fatigue
Study Details
Study Description
Brief Summary
This observational study characterizes the relationship between amniotic fluid lactate and uterine electromyography during labor in healthy, nulliparous women in spontaneous, term labor. Additional comparison measures and outcomes measures will be collected and analyzed as exploratory measures.
| Condition or Disease | Intervention/Treatment | Phase |
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Detailed Description
Elevated amniotic fluid lactate (AFL) and uterine electromyography (EMG) mathematically transformed to calculated the power density spectrum median frequency have been found separately to be associated with labor dystocia and cesarean birth. Both are hypothesized to reflect that uterine fatigue plays a role in the pathophysiology of labor dystocia for some women.
This study aims to characterize the relationship between the two measures to better understand the role of uterine fatigue in labor dystocia and triangulate biomarkers of fatigue that may lead to a better understanding of labor dystocia phenotypes.
In addition to the primary measures, comparison measures will be collected. For AFL comparison, venous whole blood lactate and capillary lactate will be collected and measured using both a point-of-care lactate meter (Stat Strip Lactate Meter, Nova Biomedical) and a table-top blood gas analyzer (Nova Prime). For EMG comparison, routine contraction monitoring data will be collected and compared to the EMG signal. Three visual analog scales on women's experiences of fatigue, anxiety, and pain will also be administered.
Additional data will be collected from the medical record to perform exploratory and hypothesis generating analysis.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Healthy Low-Risk Nulliparous Women in Spontaneous Labor Healthy Nulliparous women with a Singleton Term fetus in the Vertex position in spontaneous labor. |
Outcome Measures
Primary Outcome Measures
- Amniotic Fluid Lactate [During active labor (6-10cm) after rupture of membranes]
Amniotic fluid lactate as measured using the handheld StatStrip Lactate Meter (Nova Biomedical). This will be measured once during active labor (6-10cm) after rupture of membranes.
- Median power density spectrum of uterine electromyography [One hour after amniotic fluid collection during active labor (6-10cm) after rupture of membranes]
Uterine electromyography measured using iWorx B3G biorecorder and galvanic skin resistance monitor. Signal is recorded for one hour after amniotic fluid collection during active labor (6-10cm) after rupture of membranes
- Visual analog scale for fatigue [At the time of amniotic fluid collection (Pre-labor)]
Participants indicate their level of fatigue on a 100 mm horizontal line anchored by "no fatigue at all" (0) and "the most serious fatigue imaginable" (100). The scale will be administered at the time of amniotic fluid collection.
Secondary Outcome Measures
- Capillary Lactate [Active Labor, within 10 minutes of the amniotic fluid lactate measurement]
Capillary lactate measured using the handheld StatStrip Lactate Meter (Nova Biomedical). This will be measured within 10 minutes of the amniotic fluid lactate measurement.
Other Outcome Measures
- (Exploratory) Maternal Age [At the time of delivery]
Maternal age in years
- (Exploratory) Maternal BMI [At the time of delivery]
Maternal body mass index (kg2/cm)
- (Exploratory) Neonatal Sex [Identified by provider at time of delivery]
Neonatal sex (male/female)
- (Exploratory) Neonatal Weight [Measured by provider at time of delivery]
Neonatal weight (g)
- (Exploratory) Perinatal Mood Disorders [During the prenatal period]
Presence of perinatal mood disorders as identified by ICD 10 code, history of perinatal mood disorders recorded in the chart, or Edinburgh Postnatal Depression Score > 13
- (Exploratory) Length of Latent Labor [Immediately prior to labor]
length of latent labor in hours measured from the time the participant identifies labor onset through the time of active labor onset identified via partograph
- (Exploratory) Length of Active Labor [During labor]
length of active labor in hours measured from the time of active labor onset identified by partograph, until birth
- (Exploratory) Oxytocin Augmentation [During labor (prior to birth)]
Use of oxytocin (y/n) during labor
- (Exploratory) Fetal distress [During labor]
Fetal distress identified as category 3 fetal heart tracing during labor (Y/N)
- (Exploratory) Birth Outcome [At the time of birth]
Vaginal birth, cesarean birth, or instrumental vaginal birth
- (Exploratory) Postpartum Hemorrhage [Within the first hour after birth]
Presence of postpartum hemorrhage (Y/N) >1000 ml of blood loss
- (Exploratory) Estimated Blood Loss [Within the first hour after birth]
Blood loss (ml)
Eligibility Criteria
Criteria
Inclusion Criteria:
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Nulliparous: Woman with first pregnancy progressing beyond 20 weeks estimated gestational age
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Maternal age: 18-34 years at the due date
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Term gestation: 37-41 weeks estimated gestational age (EGA)
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Single fetus in a vertex presentation: Pregnancy with only one fetus that is in a head down position with the occiput leading into the pelvis upon admission to the hospital.
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Spontaneous onset of labor: No documented induction of labor including use of cervical ripening agents (e.g. misoprostol, cervidil), mechanical devices (e.g. cook or Foley catheter), or oxytocin including for the management of premature rupture of membranes.
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Pre-pregnancy body mass index (BMI) < 30 kg/m2: Pre-pregnancy weight and height documented in the health record on the initial prenatal visit is used to calculate BMI by dividing the pre-pregnancy weight in kilograms by the square of the pre-pregnancy height in meters. Of note, weight measured at the final prenatal visit before labor (rather than the pre-pregnancy BMI) will be used to calculate BMI at time of delivery for use as a variable in the study.
Exclusion Criteria:
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Induction of labor: Documented induction of labor including use of cervical ripening agents (e.g. misoprostol, cervidil), mechanical devices (e.g. cook or Foley catheter), or oxytocin. This does not include nipple stimulation, castor oil, herbs, or other methods of labor induction attempted by participants outside of medical care.
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Premature rupture of membranes (PROM): Rupture of membranes at term but prior to the onset of labor. Women with PROM who otherwise meet the inclusion criteria will be included, however if induction or augmentation of labor is medically required prior to the onset of active labor and collection of amniotic fluid, these women will be excluded.
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Pre-existing or gestational diabetes requiring medical management: The diagnosis of diabetes of any kind requiring management with medications including but not limited to insulin, glyburide, and metformin as indicated in the health record.
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Pre-existing or gestational hypertension or pre-eclampsia requiring medical management: The diagnosis of hypertension of any kind requiring management with medications including but not limited to long-term hypertension management such as methyldopa and short-term or emergency hypertension management such as labetalol or magnesium sulfate as indicated in the health record.
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Suspected fetal anomaly or intrauterine growth restriction: Any diagnosed fetal anomalies or intrauterine growth restriction as indicated in the health record.
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Use of exogenous oxytocin prior to sample collection: Any use of exogenous oxytocin for inducing or augmenting labor prior to the collection of amniotic fluid samples will exclude the participant from the study. Use of exogenous oxytocin following data collection will not exclude participants and data about dose and timing of medication will be collected.
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Use of amnioinfusion prior to sample collection: Amnioinfusion, the infusion of fluids into the uterus using an intrauterine catheter may affect AFL concentrations. Any amnioinfusion prior to sample collection will exclude participants from continued participation.
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Fetal distress prior to or during sample collection: Category 3 fetal heart tracing as defined by the National Institute of Child Health and Development22, absent fetal heart rate variability with recurrent late deceleration, recurrent variable decelerations, bradycardia, or sinusoidal rhythm.
Contacts and Locations
Locations
No locations specified.Sponsors and Collaborators
- University of Colorado, Denver
- National Institute of Nursing Research (NINR)
- Nova Biomedical
Investigators
- Principal Investigator: Katherine Kissler, MS, University of Colorado Anschutz Medical Campus, College of Nursing
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 19-0307
- F31NR018582-01