Fetal Heart Rate 5-tier

This app is intended for obstetricians, midwives, and nurses who use electronic fetal monitoring (EFM) in laboring patients. In addition to interpreting fetal heart rate (FHR) tracings, health care professionals must communicate with each other about the tracings in a way that is understood by all parties, and decide what action to take.

FHR 5-tier is based on the five-color system developed by Drs. Julian Parer and Tomoaki Ikeda. (AJOG July 2007) The intent of their system is to standardize management of different fetal heart rate tracings. The system divides all fetal heart rate tracings into one of five categories: Green (no acidemia, no intervention required), Blue, Yellow, Orange or Red (evidence of actual or impending fetal asphyxia, rapid delivery recommended). Each color has assigned to it a: a) risk of acidemia, b) risk of evolution to a more serious pattern and c) recommended action.

The NICHD three-tier system of classifying fetal heart rate (FHR) tracings has been criticized for having too wide a range of tracings in “Category II”. Some researchers and clinicians believe that the five-tier color-coded system more effectively classifies EFM tracings. The five-tier system is being adopted by an increasing number of hospitals in the U.S. and in Japan.

FHR 5-tier makes it easier to use the five-color system.

Without the FHR 5-tier app, one must refer to a table with 134 possible combinations of variability, baseline, and decelerations. One must also either memorize or refer to the definitions for mild, moderate and severe decelerations, which are complex and sometimes confusing.

When using the FHR 5-tier app it is not necessary to refer to any other table or chart. Variability and baseline, and the shape, nadir, and duration of decelerations are entered with buttons on the consecutive screens. The app calculates the severity of the deceleration and the color for each tracing. All aspects of the tracing are summarized on the colored results screen, so that the user can quickly communicate with others.

Management recommendations as outlined by Parer and Ikeda are given. These include whether or not the obstetrician needs to be at the bedside; what other personnel should be available; and whether the patient should be moved to the operating room. In addition, conservative management techniques are listed where appropriate. Thus, for Blue, Yellow, and Orange tracings, the final results screen reminds the user to consider actions such as maternal position change, decreasing oxytocin, or amnioinfusion.

As noted by Parer and Ikeda, the guidelines for management may need to be modified for institutions other then theirs, and may even change depending on time of day.

The NICHD Category (I, II, III) is also given on the results screen.

This application is intended as a reference tool for use only by licensed healthcare professionals. This application is not a substitute for each licensed healthcare professional's independent clinical judgment. No medical decision should be based solely on information obtained by use of this tool.


This application tries to faithfully aggregate information from major authorities (see references) and does not introduce or substitute the judgment of the makers of this application for those authorities. If you find any errors in this application, please report them to our website (http://obapps.org/contact.php)

Rebuild to upgrade for newest versions of iOS. Corrected numerous interface errors.