Prediction of intrapartum fetal hypoxia considering feature selection algorithms and machine learning models

  • Zafer Cömert
  • Abdulkadir Şengür
  • Ümit BudakEmail author
  • Adnan Fatih Kocamaz
Part of the following topical collections:
  1. Special Issue on Artificial Intelligence in Health Informatics



Cardiotocography (CTG) consists of two biophysical signals that are fetal heart rate (FHR) and uterine contraction (UC). In this research area, the computerized systems are usually utilized to provide more objective and repeatable results.

Materials and Methods

Feature selection algorithms are of great importance regarding the computerized systems to not only reduce the dimension of feature set but also to reveal the most relevant features without losing too much information. In this paper, three filters and two wrappers feature selection methods and machine learning models, which are artificial neural network (ANN), k-nearest neighbor (kNN), decision tree (DT), and support vector machine (SVM), are evaluated on a high dimensional feature set obtained from an open-access CTU-UHB intrapartum CTG database. The signals are divided into two classes as normal and hypoxic considering umbilical artery pH value (pH < 7.20) measured after delivery. A comprehensive diagnostic feature set forming the features obtained from morphological, linear, nonlinear, time–frequency and image-based time–frequency domains is generated first. Then, combinations of the feature selection algorithms and machine learning models are evaluated to achieve the most effective features as well as high classification performance.


The experimental results show that it is possible to achieve better classification performance using lower dimensional feature set that comprises of more related features, instead of the high-dimensional feature set. The most informative feature subset was generated by considering the frequency of selection of the features by feature selection algorithms. As a result, the most efficient results were produced by selected only 12 relevant features instead of a full feature set consisting of 30 diagnostic indices and SVM model. Sensitivity and specificity were achieved as 77.40% and 93.86%, respectively.


Consequently, the evaluation of multiple feature selection algorithms resulted in achieving the best results.


Biomedical signal processing Fetal heart rate Feature selection Classification Machine learning 



We would like to thanks to Dr. Sami Güngör due to its comments on the medical background.


There is no funding source for this article.

Compliance with ethical standards

Conflicts of interest

The authors declare that there is no conflict to interest related to this paper.

Ethical approval

This article does not contain any data, or other information from studies or experimentation, with the involvement of human or animal subjects.

Supplementary material

13755_2019_79_MOESM1_ESM.docx (356 kb)
Supplementary material 1 (DOCX 357 kb)


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of Software EngineeringSamsun UniversitySamsunTurkey
  2. 2.Department of Electrical and Electronics Engineering, Technology FacultyFirat UniversityElazigTurkey
  3. 3.Department of Electrical and Electronics EngineeringBitlis Eren UniversityBitlisTurkey
  4. 4.Department of Computer Engineeringİnönü UniversityMalatyaTurkey

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