The Term-Preterm EHG Database (TPEHG DB)

(First Edition, November 2010, revised August 2012)

This database is described in

Gašper Fele-Žorž, Gorazd Kavšek, Živa Novak-Antolič and Franc Jager. A comparison of various linear and non-linear signal processing techniques to separate uterine EMG records of term and pre-term delivery groups. Medical & Biological Engineering & Computing, 46(9):911-922 (2008).

Please cite this publication when referencing this material, and also include the standard citation for PhysioNet:

Goldberger AL, Amaral LAN, Glass L, Hausdorff JM, Ivanov PCh, Mark RG, Mietus JE, Moody GB, Peng C-K, Stanley HE. PhysioBank, PhysioToolkit, and PhysioNet: Components of a New Research Resource for Complex Physiologic Signals. Circulation 101(23):e215-e220 [Circulation Electronic Pages; http://circ.ahajournals.org/cgi/content/full/101/23/e215]; 2000 (June 13).

The Electrohysterogram records (uterine EMG records) included in the Term-Preterm ElectroHysteroGram DataBase (TPEHG DB) were obtained from 1997 to 2005 at the University Medical Centre Ljubljana, Department of Obstetrics and Gynecology. The records were obtained during regular check-ups either around the 22nd week of gestation or around the 32nd week of gestation. The women participating in the study represented a sample of the general population. In all, almost 1300 records were obtained during these years, and a preliminary database was built and used for studies by Ivan Verdenik, Gorazd Kavšek, Marjan Pajntar and Živa Novak-Antolič [1],[2].

The TPEHG DB posted here contains 300 uterine EMG records from 300 pregnancies (one record per pregnancy) carefully selected from the original database of which:

During the selection of records, all records with apparent recording artifacts, all records from pregnancies where labor was induced, and all records where delivery was performed using a Cesarean section, were rejected.

Each record is composed of three channels, recorded from 4 electrodes:

The differences in the electrical potentials of the electrodes were recorded, producing 3 channels:

The individual records are 30 minutes in duration. Each signal has been digitized at 20 samples per second per channel with 16-bit resolution over a range of ±2.5 millivolts.

Each signal was digitally filtered using 3 different 4-pole digital Butterworth filters with a double-pass filtering scheme. The band-pass cut-off frequencies were:

The records in the database contain both the original and filtered signals. The records are in WFDB format. Each record consists of two files, a header file (.hea) containing information regarding the record and the data file (.dat) containing signal data.

The comment section in the header files (.hea) includes clinical information, such as:

* These eight items of clinical information were added to the header files in August 2012. No other changes were made.

The signal data in the data files (.dat) are in the following order:

When using filtered channels, note that the first and last 180 seconds of the signals should be ignored since these intervals contain transient effects of the filters.

An accompanying file (tpehgdb.smr) summarizes clinical information of each record, describing whether the corresponding pregnancy ended on term (> 37 weeks) or prematurely (≤ 37 weeks), and whether the record was obtained before the 26th week of gestation or during or after the 26th week of gestation.

The columns in the tpehgdb.smr file represent:

The TPEHG DB as posted here was the database used during a study of separating uterine EMG records of term and pre-term delivery groups using various linear and non-linear signal processing techniques [3]. Please cite reference [3] if using the records of the TPEHG DB.

During a study on comparison of various linear and non-linear signal processing techniques to separate uterine EMG records of term and pre-term delivery groups [3], among the other, following non-linear signal processing techniques to calculate following features for the records were used:

The feature values for all filtered signals of the records of the database are included in the feature values files (.fvl) of the database. For further details on how the features were calculated, see [3].

The .fvl files are organised according to the filter used:

The columns in the .fvl files represent:

For further information, please contact:

Franc Jager
Laboratory of Biomedical Computer Systems and Imaging
University of Ljubljana
Faculty of Computer and Information Science
Trzaska 25
1000 Ljubljana, Slovenia
email: franc.jager@fri.uni-lj.si

References:

  1. Ivan Verdenik. Multilayer prediction model for preterm delivery. PhD thesis. University of Ljubljana, Medical faculty, Ljubljana, 2002.
  2. Gorazd Kavšek. Electromyographic activity of the uterus in threatened preterm delivery. MsC thesis. University of Ljubljana, Medical faculty, Ljubljana, 2001.
  3. Gašper Fele-Žorž, Gorazd Kavšek, Živa Novak-Antolič and Franc Jager. A comparison of various linear and non-linear signal processing techniques to separate uterine EMG records of term and pre-term delivery groups. Medical & Biological Engineering & Computing, 46(9):911-922 (2008). [PDF]
Icon  Name                                        Last modified      Size  Description
[PARENTDIR] Parent Directory - [   ] RECORDS 2012-02-25 03:26 5.2K list of records [   ] tpehgdb.pdf 2010-11-25 05:25 918K MBEC 2008 paper [   ] tpehgdb.smr 2010-11-25 05:25 19K notes on records [DIR] tpehgdb/ 2016-03-22 15:58 - records [   ] tpehgdb_features__filter_0.08_Hz-4.0_Hz.fvl 2011-08-29 11:39 98K records [   ] tpehgdb_features__filter_0.3_Hz-3.0_Hz.fvl 2011-08-29 11:39 98K records [   ] tpehgdb_features__filter_0.3_Hz-4.0_Hz.fvl 2011-08-29 11:39 98K records
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