Carbohydrate-Optimized Nutritional Solution Versus Electrolyte Hydration in Labor

September 8, 2026 updated by: Olga Casanova, Institut Investigacio Sanitaria Pere Virgili

Pilot Randomized Controlled Trial Evaluating Carbohydrate-Optimized Nutritional Solution Versus Electrolyte Hydration in Active Labor With Epidural Analgesia in Low-Risk Pregnant Women

This is a pilot randomized, triple-blind clinical trial (pilot RCT) evaluating the preliminary effects of energy supplementation with carbohydrate-rich sports gels compared to a low-sugar sports drink during labor in low-risk pregnant women receiving epidural analgesia.

Labor is associated with substantially increased metabolic demands, while current evidence on intrapartum carbohydrate supplementation remains heterogeneous. This study investigates whether a carbohidrate solution formulation containing improves maternal and neonatal outcomes compared to an other.

A total of 142 term, low-risk pregnant women will be recruited at a single hospital center and randomized to receive either the sports gel or the control beverage. The intervention will begin 60 minutes after epidural analgesia and be repeated every 3 hours until delivery, with a maximum of 4 units administered per participant.

The primary objective is to obtain preliminary estimates of the intervention effects on labor duration and obstetric and neonatal outcomes. Secondary outcomes include cardiotocography patterns, maternal and neonatal glucose levels, postpartum hemorrhage, vomiting episodes, and maternal satisfaction.

This trial was prospectively registered. The study was initially conceived as a pilot randomized controlled trial within an institutional research framework, and registration was completed after participant recruitment had been completed to ensure transparency and adherence to international reporting standards.

The results of this pilot study will inform the design of a future large-scale randomized controlled trial.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

Background Pregnancy involves an increase in anabolic metabolism, especially during the third trimester due to continuous fetal and placental growth. During active labor, metabolic demands increase further, reaching levels comparable to moderate or intense physical exercise. A 10-hour labor with epidural analgesia may not be adequately supported by clear liquids, saline, or glucose alone; nutritional support should be better adapted to the energy needs of laboring women.

Recent studies have shown mixed results regarding carbohydrate intake during labor, without a consistent effect on labor duration or mode of delivery, although some evidence suggests benefits for maternal comfort and neonatal glycemia

. A 2016 meta-analysis involving 691 women found that oral carbohydrate supplements in small amounts (mean difference of 195 kcal) did not significantly alter labor duration, cesarean rates, or instrumental delivery rates. A large multicenter trial with 3,984 women found no differences in instrumental delivery rates between carbohydrate and fasting groups.

However, a Chinese multicenter trial involving 1,953 primigravid women with epidural analgesia reported reduced maternal hunger and lower neonatal hypoglycemia with carbohydrate supplementation, although higher rates of maternal and neonatal hyperglycemia were observed.

Aspiration Concerns and Modern Practice Historical restrictions on oral intake during labor stem from Mendelson's 1946 description of aspiration risk during general anesthesia. However, modern obstetric anesthesia has evolved considerably, with neuraxial techniques now standard and general anesthesia rarely used for childbirth. Current guidelines from the American College of Obstetricians and Gynecologists (ACOG) and the American Society of Anesthesiologists (ASA) recommend a moderate intake of clear liquids during an uncomplicated labor, while solid foods are generally avoided.The incidence of aspiration in modern obstetric practice is extremely low.

Myometrial Energy Metabolism and Uterine Perfusion From a physiological perspective, the uterus is an extraordinarily active muscle that significantly increases its energy demand during pregnancy and labor.As a myogenic organ, it generates rhythmic contractions without direct nerve stimulation, and its function critically depends on a continuous supply of metabolic substrates. Uterine perfusion illustrates this need: blood flow increases from approximately 45 mL/min in the non-pregnant state to nearly 750 mL/min at the end of gestation.

The causes of delayed labor can be related to the four "P"s: power, passenger, passage, and psyche. Insufficient power can occur when the myometrium is not adequately loaded with glycogen before labor, leading to myometrial dysfunction. Uterine atony, associated with low contractility, causes between 70 and 80% of postpartum hemorrhages, which are estimated to occur in 5-10% of all births.

Glucose as the Primary Myometrial Fuel Glucose is the primary energy source for the myometrium. Glucose concentrations in uterine tissue at the end of pregnancy vastly exceed those in striated muscle. Glycogen stores increase during gestation as a strategic reserve but are rapidly consumed once labor begins. This depletion has been associated with a higher risk of ineffective contractions and uterine dysfunction.

Mitochondria play a central role in this process. Oxytocin increases mitochondrial depolarization, stimulating ATP production and modulating the rhythmicity of contractions.When glucose availability decreases, the myometrium increases its reliance on anaerobic glycolysis, manifesting in an accumulation of lactate and adenosine, which are classic markers of myometrial fatigue. Despite clear physiological evidence highlighting glucose and adequate hydration as critical components for optimal myometrial contractility, restrictive oral intake policies continue to influence modern obstetric care.

To address this clinical discrepancy, this Randomized Clinical Pilot Trial was designed.

Study Design and Methodology This is an experimental, analytical, and triple-blind randomized controlled pilot trial conducted according to CONSORT guidelines. Participants, clinical staff (midwives), and outcome assessors are blinded to group allocation. The study takes place at the Hospital Universitari de Tortosa Verge de la Cinta (HUTVC), Tarragona, Spain.

Group allocation is random and concealed. The hospital pharmacy prepares intervention packages (4 units per participant) and assigns a unique code to each package. The pharmacy maintains a database linking the codes with the intervention type, but does not have access to the identities of the participants. Midwives dispensing the products are unaware of the group allocation. Both interventions were prepared in identical opaque containers with standardized volume, appearance, and labeling.

Interventions and Administration Protocol Intervention Group (High-carbohydrate sports gel): The gel contains a carbohydrate blend designed to promote sustained energy availability.

Control Group (Low-carbohydrate hydrogel): The product contains a lower carbohydrate content. It is modified using a food-grade thickening agent (xanthan gum) to match the viscosity and mouthfeel of the sports gel, ensuring both interventions are indistinguishable.

The first dose is administered 60 minutes after epidural insertion to prevent confounding effects related to the epidural. Subsequent doses are administered every 3 hours during active labor, up to a maximum of 4 doses per participant. Oral water intake is encouraged throughout labor (150-200 mL/hour)

Study Type

Interventional

Enrollment (Estimated)

147

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Pregnancy classified as Normal Pregnancy, Low-Risk Pregnancy, or Medium-Risk Pregnancy according to the "Protocol de seguiment de l'embaràs a Catalunya" and "Protocol de naixement i acompanyament al naixement de Catalunya".
  • Use of epidural analgesia during labor.
  • Ability to understand Catalan and/or Spanish.
  • Term pregnancy (≥37 weeks gestation).
  • Cephalic presentation.
  • Spontaneous onset of labor, OR induced labor due to prolonged pregnancy or premature rupture of membranes (regardless of duration).
  • Prenatal care at ASSIR Terres de l'Ebre with planned delivery at Hospital Universitari Tortosa Verge de la Cinta.
  • Signed informed consent prior to labor.

Exclusion Criteria:

  • Gestational diabetes (including diet and exercise controlled).
  • Multiple gestation.
  • Labor not documented in partograph.
  • Informed consent not signed prior to labor.
  • Medical indication requiring administration of glucose or glucose-saline intravenous solution during labor (withdrawal criterion).

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Supportive Care
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: High carbohydrate sports gel
Participants receive a carbohydrate solution named High carbohydrate sports gel.The solution contains a mixture of carbohydrates designed to support sustained energy availability. The product is administered 60 minutes after epidural placement and subsequently every 3 hours during active labor, up to a maximum of four administrations. Water intake is encouraged throughout labor.
Dietary supplement: High carbohydrate sports gel

High carbohydrate sports gel (Intervention): The gel provides energy intake with low gastric volume.

Low carbohydrate hydrogel (Control Description): A lower-sugar solution. The product is thickened using a food-grade agent to match the viscosity and palatability of the sports gel, ensuring comparability between interventions.
Active Comparator: Low carbohydrate hydrogel
Participants receive a low carbohydrate hydrogel. It is modified with xanthan gum (a food-grade thickening agent) to match the viscosity and palatability of the High carbohydrate sports gel. Administration follows the same schedule as the intervention group: first dose 60 minutes after epidural placement and then every 3 hours during active labor, up to a maximum of four administrations.
Dietary supplement: Low carbohydrate hydrogel
Low carbohydrate hydrogel. Matched in appearance, texture, and administration schedule to the experimental intervention to maintain participant and provider blinding.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Duration of Labor
Time Frame: Timing of epidural analgesia administration to delivery (approximately 1-12 hours).
Time elapsed from epidural catheter insertion until delivery, measured in minutes. Recorded by attending midwife on data collection form.
Timing of epidural analgesia administration to delivery (approximately 1-12 hours).

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Postpartum Hemorrhage
Time Frame: Within 24 hours postpartum
Presence of postpartum hemorrhage defined as blood loss > 500 mL (yes/no).
Within 24 hours postpartum
Maternal Vomiting Episodes
Time Frame: From first study product administration to delivery
Number of vomiting episodes during active labor (count variable).
From first study product administration to delivery
Maternal Blood Glucose
Time Frame: 60 minutes after study product administration (repeated if labor exceeds 3 hours)
Capillary blood glucose level measured 60 minutes after intervention administration. Recorded in mg/dL.
60 minutes after study product administration (repeated if labor exceeds 3 hours)
Maternal Satisfaction
Time Frame: Within 24 hours postpartum
Maternal satisfaction with labor nutritional support measured using CSTA scale (Client Satisfaction Scale). 5-point ordinal scale: very satisfied, satisfied, neutral, somewhat dissatisfied, very dissatisfied.
Within 24 hours postpartum
Neonatal APGAR Score (1, 5, 10 minutes).
Time Frame: 1, 5 and 10 minutes after birth.
Standard APGAR score (0-10).
1, 5 and 10 minutes after birth.
Cardiotocographic Classification
Time Frame: During active labor until delivery

Fetal heart rate tracing classification according to Spanish clinical practice guidelines for normal birth care. Categorized as: reassuring, non-reassuring, or abnormal.

GUIDELINE: Fetal monitoring in labor. NICE guideline [NG229] Published:14 December 2022
During active labor until delivery
Neonatal Blood Glucose
Time Frame: 60-120 minutes after birth
Capillary blood glucose level in the newborn. Recorded in mg/dL.
60-120 minutes after birth

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Institut Investigacio Sanitaria Pere Virgili

Collaborators

Institut Catala de Salut

Investigators

  • Principal Investigator: Olga Casanova Callau, Midwife, Institut de Recerca Biomèdica Catalunya Sud (IRBCatSud), Tortosa, Spain; Servei de Paritori, Hospital Universitari de Tortosa Verge de la Cinta, Institut Català de la Salut, Tortosa, Spain.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

September 1, 2025

Primary Completion (Estimated)

September 30, 2026

Study Completion (Estimated)

September 30, 2026

Study Registration Dates

First Submitted

July 25, 2026

First Submitted That Met QC Criteria

July 29, 2026

First Posted (Actual)

August 3, 2026

Study Record Updates

Last Update Posted (Actual)

September 9, 2026

Last Update Submitted That Met QC Criteria

September 8, 2026

Last Verified

September 1, 2026

More Information

Terms related to this study

Keywords

Other Study ID Numbers

  • 084/2023

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared. This is a single-center, investigator-initiated pilot randomized controlled trial conducted within a public healthcare setting, and there is currently no formal data sharing infrastructure in place. All data are de-identified and securely stored in accordance with institutional and data protection regulations. Data sharing may be considered in the future following publication of the primary results and development of appropriate data governance procedures.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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