Foley Catheter for Labor Induction: Procedure, Effectiveness & Risks

Labor induction is a common obstetric intervention used when continuing pregnancy poses risks to the mother or fetus. Several methods are available, including pharmacological agents and mechanical techniques. One of the most widely used mechanical methods is the Foley catheter, a safe and effective way to ripen the cervix and initiate labor.

A Foley catheter is a flexible, sterile tube with an inflatable balloon at one end. It is primarily used for urinary catheterization but is also employed in obstetrics for cervical ripening and labor induction.

Key Characteristics of the Foley Catheter for Labor Induction:

• Mechanical Cervical Ripening: Physically dilates the cervix to encourage labor.

• Balloon Inflation Mechanism: The balloon applies pressure to the cervix, stimulating prostaglandin release.

• Non-Pharmacological Approach: Can be used alone or in combination with other induction methods.

• Temporary Placement: Typically remains in place for 12–24 hours or until spontaneous expulsion occurs.

• Post-Term Pregnancy: Used when pregnancy extends beyond 41 weeks.

• Medical Indications: Recommended for conditions such as preeclampsia, gestational diabetes, or intrauterine growth restriction (IUGR).

• Unfavorable Cervix (Bishop Score <6): Helps prepare the cervix when it is not yet ready for labor.

• Avoidance of Pharmacological Agents: Preferred in cases where medication-based induction may pose risks.

The Foley catheter induces labor by mechanically dilating the cervix and promoting prostaglandin release.

Mechanism of Action:

1. Insertion: A deflated Foley catheter is inserted into the cervix through the vaginal canal.

2. Balloon Inflation: The balloon is inflated with sterile saline (usually 30–60 mL) to apply gentle pressure on the cervix.

3. Cervical Ripening: Continuous pressure stimulates prostaglandin production, softening and dilating the cervix.

4. Spontaneous Expulsion: As the cervix dilates (typically 3–4 cm), the catheter falls out naturally.

5. Labor Progression: If necessary, additional interventions (oxytocin or artificial rupture of membranes) are used to strengthen contractions.

• Foley Catheter: Mechanical dilation through direct pressure.

• Pharmacological Methods: Use of prostaglandins or oxytocin to stimulate contractions.

• Foley Catheter: Gradual, typically within 12–24 hours.

• Pharmacological Methods: May act faster but have variable response rates.

• Foley Catheter: Lower risk of uterine hyperstimulation.

• Pharmacological Methods: Higher risk, especially with prostaglandins.

• Foley Catheter: Can be removed immediately if complications arise.

• Pharmacological Methods: Effects may persist even after discontinuation.

• Foley Catheter: Safer option for VBAC candidates.

• Pharmacological Methods: Increased risk of uterine rupture in VBAC cases.

• Non-Pharmacological and Safe: Reduces reliance on medications.

• Lower Risk of Hyperstimulation: Unlike prostaglandins, it does not excessively stimulate uterine contractions.

• Can Be Used in VBAC Candidates: Considered safer for those with a history of cesarean delivery.

• Effective in Women with an Unfavorable Cervix: Helps in cervical ripening for women with low Bishop scores.

While generally safe, the Foley catheter method carries some risks:

1. Discomfort or Pain: Some women experience cramping or discomfort during insertion and inflation.

2. Vaginal Bleeding: Mild bleeding or spotting is common.

3. Infection Risk: Though rare, improper insertion can lead to infection.

4. Premature Rupture of Membranes (PROM): In some cases, the catheter may cause early rupture of membranes.

5. Ineffectiveness: May not be sufficient for labor induction in all cases, requiring additional interventions.

• Mild cramping and discomfort.

• Gradual cervical dilation.

• Spotting or light vaginal bleeding.

• Severe pain or persistent contractions.

• Heavy vaginal bleeding.

• Signs of infection (fever, foul-smelling discharge).

• Sudden loss of fetal movement.

Case Study:

Mrs. Verma, a 40-week pregnant woman with gestational diabetes, arrives at the hospital for labor induction. Her Bishop score is 4, indicating an unfavorable cervix. After discussing options, her obstetrician recommends the Foley catheter.

Procedure:

• A 16 Fr Foley catheter is inserted into her cervix and inflated with 50 mL of sterile saline.

• She experiences mild cramping but no severe pain.

• After 12 hours, the catheter falls out, and her cervix is 4 cm dilated.

• Labor progresses with the addition of oxytocin, leading to a successful vaginal delivery.

Outcome:

Mrs. Verma delivers a healthy baby with minimal intervention, avoiding pharmacological cervical ripening.

The Foley catheter is a widely used, effective method for labor induction, particularly in cases requiring cervical ripening. It is a safer alternative for women with previous cesarean deliveries or those who cannot use pharmacological agents.

Understanding its benefits, risks, and proper usage allows pregnant women and healthcare providers to make informed decisions about labor induction. If concerns arise during the induction process, seeking immediate medical attention is crucial.