Internal electronic fetal monitoring is an invasive procedure in which an internal spiral electrode (ISE) is attached to the presenting fetal part (usually the scalp) and a fluid-filled intrauterine pressure catheter (IUPC) is inserted into the uterine cavity alongside the fetus.

The ISE detects the fetal heart rate (FHR) and transmits it to the monitor, converting the signal to a fetal electrocardiogram (ECG) waveform.

A continuous recording of the FHR is thus provided.

This procedure demonstrates an accurate baseline, true baseline variability, and periodic changes (transient and recurrent changes from baseline rates that are associated with uterine contractions).

Internal electronic fetal monitoring is indicated for high-risk pregnancies.

Maternal risk includes complications such as uterine perforation and intrauterine infections.

Fetal risk includes such complications as abscess, hematoma, and infection.

The IUPC is usually removed during the second stage of labor.

This procedure is also called direct monitoring.

Electronic fetal monitor and operating instructions

Spiral electrode and drive tube

Disposable leg pad or reusable leg pad with Velcro belt

Conduction gel

Antiseptic solution

Hypoallergenic tape

Sterile gloves

Sterile drapes

IUPC connection cable and pressure sensitive catheter

Graph paper

Explain the procedure to the patient.

Label the printout paper with the patient’s identification number or name, birth date, the date, the paper speed, and the number on the monitor strip.

Help the patient into the lithotomy position for a vaginal examination.

Attach the connection cable to the outlet on the monitor marked UA (uterine activity); connect the cable to the IUPC, and then zero the catheter with a gauge on the distal end of the catheter.

Cover the patient’s perineum with a sterile drape and clean the perineum according to facility policy.