A 28-year-old primigravida at 40 weeks with an unfavorable cervix requires induction of labor. A Foley catheter is inserted through the cervical canal for mechanical ripening. What volume of saline is typically used to inflate the balloon for this purpose?
- A 10 mL
- B 30 mL ✓
- C 60 mL
- D 100 mL
Correct answer: B. 30 mL
Explanation
Standard practice for mechanical cervical ripening with a Foley catheter involves inflating the balloon with 30 mL of saline. This volume provides adequate traction and pressure against the internal os to stimulate local prostaglandin release. Volumes like 100 mL are excessive and risk balloon rupture or uterine irritation.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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