Maternal and Fetal Monitors: Types and Equipment Features

A fetal monitor is an obstetric system used to record information about the baby and, depending on its configuration, the pregnant woman. Timely monitoring can help the maternity team assess their condition and plan care. It does not, by itself, guarantee a healthy pregnancy or birth.

Assessment using monitoring equipment

Monitoring provides physiological measurements that clinicians can use when assessing the baby and recognising possible problems. The original article lists maternal breathing rate and rhythm, pulse and blood pressure, alongside fetal heart rate, movement, arrhythmias, intrauterine pressure and electrocardiogram (ECG) data. This is a description of possible functions across different systems, rather than a specification shared by every fetal monitor. Respiratory measurements may require additional maternal monitoring equipment; an abnormal heart-rate trace is not, on its own, a diagnosis of an arrhythmia.

It is also important to distinguish the measurement methods. An external contraction sensor records uterine activity, but does not measure absolute intrauterine pressure. Internal pressure measurement and direct fetal ECG require specific equipment and clinically appropriate procedures. The Philips Avalon instructions for use distinguish external TOCO monitoring from internal pressure and direct ECG options; these capabilities depend on the particular model and configuration.

Manufacturers offer ranges with different combinations of functions. Before purchasing a system, establish which measurements and clinical uses are required, then check the exact model’s documentation. For example, the Huntleigh TEAM3 antepartum instructions describe a monitor intended for trained healthcare professionals, with specified pregnancy-related uses and compatible accessories. This particular version’s intended use should not be extended automatically to every stage of labour or to other models.

The original article favours established manufacturers and reports strong demand for European-made systems and accessories. These are the source’s market observations. Country of manufacture alone does not establish accuracy, regulatory compliance or suitability. Its suggested manufacturer-selection criteria remain useful:

• The brand’s reputation.
• Its experience in fetal monitoring.
• Feedback about the manufacturer and the confidence it has earned among healthcare professionals.

Choosing a device: key requirements

A cardiotocograph (CTG monitor) should meet the service’s clinical and technical requirements. Where continuous monitoring is indicated, it must reliably measure, record and display the required signals. Clear numerical displays and readable traces are important; a CTG trace is a record of heart rate and uterine activity, rather than an anatomical image.

The original article identifies two aspects of uterine activity to review alongside the fetal heart-rate trace:

• The pattern of uterine activity during labour.
• The frequency and duration of contractions.

These observations can help clinicians assess changes in contraction duration or prolonged uterine activity, including possible hypertonus. A monitor cannot guarantee that it will identify every abnormality or determine the correct response automatically. NICE’s guidance on fetal monitoring in labour places CTG interpretation within the whole clinical picture and stresses the need to distinguish the maternal heartbeat from the baby’s. Its intrapartum interpretation recommendations should not simply be applied to antenatal traces.

Recording, saving, exporting and printing facilities can support later analysis and review of care. Check which functions the chosen system actually provides and how records will be retained. The source suggests that these records can make clinicians’ work more transparent. They can contribute to an audit, but a trace alone cannot establish professional competence or fully explain the decisions made during care.

Accessories and supporting documentation

Appropriate sensors are essential and may be supplied with the monitor or purchased separately. Compatible software can assist recording and review; systems with a printer also need the correct chart paper. Use manufacturer-approved probes, accessories and supported software, and follow the model’s cleaning and maintenance instructions.

Check the registration or conformity documentation required in the country of use, together with detailed instructions for the exact device. Documentation is necessary for assessing suitability and lawful supply, but does not guarantee flawless measurements. The source mentions Doppler-based monitors, models for singleton pregnancies and systems with additional functions. Twin-capable models need separate fetal channels and appropriate probes: these measure the two babies, rather than duplicating maternal monitoring.

Detailed instructions help staff learn a new system, alongside appropriate training. For Doppler ultrasound functions, the FDA’s ultrasound information explains that prudent use by trained healthcare professionals matters. Untrained use can lead to misleading interpretations and unnecessary exposure; detecting a heartbeat should not be treated as reassurance that replaces clinical assessment.

Source: Zaplata: Maternal and Fetal Monitors: Types and Equipment Features. Russian article on MEDICTUR.