Engineering, 2013, 5, 272-276
http://dx.doi.org/10.4236/eng.2013.510B057 Published Online October 2013 (http://www.scirp.org/journal/eng)
Characterization of Pathologic Cries of Newborn s Based
on Fundamental Frequency Estimation
Yasmina Kheddache, Chakib Tadj
Electrical Engineering Department, École de technologie Supérieure, Montréal, Canada
Received June 2013
ABSTRACT
The majority of the sick babies seem in good health at birth and early diagnosis of the various pathologies that can af-
flict newborn is crucial. For this reason we introduce in this paper the use of the fundamental frequency and the differ-
ent modes of cries as Hyper-phonation, phonation and high pitched cries to differentiate the pathological cries from the
cries of the healthy babies. The auto matic estimation of these characteristics en abled us to establish a quantitative ch a-
racterization of healthy newborn cries and pathologic newborn cries. The results obtained agree with the spectrogr aphic
analysis carried out on the healthy and pathologic cries of the newborns.
Keywords: Newborns’ Cry; Fundamental Frequency; Cry Modes
1. Introduction
For many researchers, the fundamental frequency F0
which represents the spe ed of opening and closure of the
vocal folds [1] is considered as the most important in the
perception of the infant’s cries by adults. Generally the
increase of F0 is asso ciated with a negative perception of
the cries. The cries with a high F0 are valued as aversive,
sign of emergency, distress and disease [2].
Cry analysis can be an additional tool in the clinical
diagnosis of newborn. The fundamental frequency of
newborn cry has been found to be a discriminative cha-
racteristic in several medical problems [1].
Cry analysis presented in this paper falls within the
research on the relationship between the disease and the
characteristics of the cry. Newborns do not have phona-
tory control due to neurological immaturity at early age
[3]. The main objective of this work is to analyze cries of
healthy and newborn with different categories of diseases
in order to evaluate a fundamental frequency of these
cries. We also establish quantitative relationships be-
tween the di f f erent modes of cries and st u died pathology.
The SIFT algorithm ‘Simple Inverse Filtering Track-
ing’ is used for estimation of the fundamental frequency
because the performance of this algorithm has been
tested on a real database of cri es by [4 ,5] .
This paper is organized as follows: Section 2 presents
definitions of fundamental frequency of cries. Section 3
presents previous works. Section 4 presents our adopted
methodology for automatic estimation of F0, phonic,
hyper-phonic and high pitched segments for healthy and
pathological cries. Section 5 presents the database used
in this study. The next sections present the results ob-
tained and we conclude this paper with a conclusion.
2. Fundamental Frequency of Cries
Fundamental frequency (F0) is the average vibratory
frequency (in Hz) of the vocal folds. The sound spectro-
gram displays the voiced tone as black lines. The funda-
mental frequency is the lowest line and its harmonics
appear above it as parallel lines. The maximal funda-
mental frequency corresponds to the highest measurable
point of the fundamental frequency and the minimal fun-
damental frequency corresponds to the lowest measura-
ble point of the fundamental frequency on the spectro-
gram [6].
Lester et al. [2] defines three identifiable modes of
cries due to vocal cord vibrations: 1) Basic cry or phona-
tion with F0 350 - 750 Hz ; 2) Cry with high fundamental
frequency F0 (750 - 1000 Hz) or Hyper-phonation F0
(1000 - 2000 Hz) and 3) Noisy, turbulent or dysphonic
cries.
3. Previous Works
Several authors focused their investigations on the
healthy children since birthday to one year age. Their
work is based on obs ervation and spe ctrograph ic analysis
of healthy and pathological cries signals of newborns.
They found that there is no significant difference be-
tween the preterm newborn cries and the full-term new-
born cries. They also found that there is not variation of

Y. KHEDDACHE, C. TADJ
273
F0 compared to the sex and the gestational age [3]. In the
case of the newborn with various pathologies, it was
shown that the level of the cries is high and presents a
weak punctuation, high irritability and low physiological
stability [1,3].The authors in this research area show that
the cries of healthy full-term newborn are characterized
by an F0 varying between 400 and 600 Hz and averaging
450 Hz [5,7]. The cries of healthy premature newborns
can be more intense or similar to the cries of full-term
newborns [1]. The cries of newborns with neurological
disturbances exhibit auditory abnormalities [6]. Hyper-
phonic cries and very high-pitched cries are associated
with neurological problems [2] and neonatal risk [8].
4. Methodology
Our methodology for the characterization of healthy and
pathologic cries based on F0 estimation is represented on
the simplified diagram blocks illustrated in Figure 1.
The following approach was taken when estimating
fundamental frequency and the different frequency modes
of cries:
• Recording of healthy and pathologic cries of new-
borns.
• Noise filtering and segmenting recordings into useful
and non-useful portions.
• Estimation of F0 in short intervals typically of 20 ms
interlaced frame with 10 ms recovering using SIFT
algorithm (Simple Inverse Filtering Tracking) [4,9].
The main steps of this algorithm are presented in
Figure 2.
• Estimating of phonic and hyper-phonic segments, as
well as segments with high F0 as defined in Table 1
for all cries studied.
• Identification of relationships between cries cha-
racteristics and studied pathologies.
Figure 1. Newborn cries characterization based on F0 esti-
mation.
Figure 2. The main steps of SIFT algorithm.
Table 1. Measured characteristics of cries.
Characteristics Definition
Hyper-phonation The average percentage of 20 ms blocks
having a F0 >1000 Hz.
Phonation The average percentage of 20 ms blocks
having a F0 < 750 Hz
High-pitched The average percentage of 20 ms blocks
having a F0 in the 750 - 1000 Hz range
5. Database: Cry Recording
The database used con tains 2800 cry samples of 1s dura-
tion from 48 of newborn babies. 1774 from healthy
newborn (among them 764 are premature) and 1010 from
newborn who present some diseases (among them 628
are premature) as shown in Table 2.
These cries were collected with the aid of medical
collaborators of neonatology department at Saint-Justine
Hospital in Montreal. They concern full-term and pre-
term newborn aged 1 to 30 days. The conditions in which
the cries are registered are: hunger, sampling blood,
change of d iapers. The recording of cries is done using a
small recorder, at a distance of 10 cm of babies’ mouth
with a sampling rate of 44.1 kHz.
For each baby, three recordings of duration 2 to 3 mi-
nutes are made with at least one hour interval after each
recording session (over a period of ten days at most). The
time, date and gender, date of birth, diagnosis, and reason
of cries are noted for each episode of cry.
6. Results and Analysis
We developed our own measuring tool using Matlab.
Preprocessing Segmentation
Filtering
F0 Estimation
Cry Signal Recording
Characteristics Estimation
Identification of relations
between characteristics and
studied pathologies.
Multiplying each frame by
Hamming window
Performing glottal inverse filtering
Dividing signal into overlapping
frames of 20ms with 10ms
recovering
Autocorrelation sequence
estimation.
Peak picking and decision
algorithm with voiced threshold
F0 estimation, T0= 1/F0
Smoothing using median filter

Y. KHEDDACHE, C. TADJ
274
Table 2. Pathologies studied.
Category Pathology Sample size
Full-term
newborn (t)
Healthy 1010
Thrombosis in the vena cava 77
Meningitis 115
Asphyxia 190
Preterm
newborn (P)
Healthy 764
IUGR- Microcephaly
(Intra-Uterine Growth Retardation) 78
Gastroschisis 280
RDS (respiratory distress Syndrome) 270
This tool estimates F0 as well as the average percentages
of phonic, hyper-phonic and high pitched segments.
Examples of spectrograms and F0 estimation are reported
in Figure 3 for two pathologic cries (asphyxia and ga-
stroschisis) and also for a healthy newborn. Notice high
F0 and more irregular sp ectrograms and F0 for patholog -
ic cries compared to healthy cry. The range of F0 for
pathologic cries is 150 Hz - 1600 Hz and for healthy cry
around 450 Hz. The estimated values of frequency cha-
racteristi cs lis ted in Tab le 1 for healthy and pathologic
newborn’s cry are presented in Fig ures 4 and 5 ac-
cording to pathologies studied and gestational age of
babies.
The results from this study show in Figure 4 that the
cries of healthy full-term or preterm newborns are rather
phonics with a presence of 89% of segments with a F0 <
750 HZ and round 9% of segments with high F0 > 750
Hz. Figure 5 shows that the cries of healthy fu l l -term or
preterm newborns contain round 6% of Hyper-phonic
segment. On the other hand, the cries of the sick new-
borns contain more pitched and hyper-phonic segment
compared to the healthy newborns. According to the pa-
thologies studied, the percentage varied from 11% to
28% of segments with a F0 > 750 Hz. These percentages
vary from one pathological condition to another, and are
dependant to level of prematurity.
We notice in Fi gures 4 and 5, which the cries of new-
borns with asphyxia contain 28% of high pitched seg-
ments (F0 > 750 Hz) among them 25% are hyperphonic.
In the case of meningitis, the cries contain respectively
11% and 8% of high pitched segments (F0 > 750 Hz) and
hyper-phonic segments.
The cries of newborns with microcephaly associated
with IUGR present 25% of high pitched segments (F0 >
750 Hz). These cries are more hyper-phonic with 17% of
segment with F0 > 1000 H z. The cries o f newborns with
congenital malformation gastroschisis contain 13% of
high pitched segments with F0 > 750 Hz. The percentage
of hyperphonation is 10% of segment with F0 > 1000 Hz.
The cries of newborns with heart defect (Thrombosis
(a)
(b)
(c)
Figure 3. Spectrograms and F0 estimation for healthy and
pathologic cries. (a) Full-Ter m healthy baby; (b) Full-Term
baby with Asphyxia; (c) Premature baby with gastr oschisis.

Y. KHEDDACHE, C. TADJ
275
Figure 4. The average percentage of phonic and high pitched segments (F0 > 750 Hz) by pathologies.
Figure 5. The average percentage of hyper-phonic (F0 > 1000 Hz) and high pitched segments (750 < F0 < 1000 Hz) by pa-
thologies.
in the vena cava), include 20% of segments with F0 >
750 Hz, among them 14% are hyper-phonic. The cries of
newborn with RDS (Respiratory Distress Syndrome)
include 15% of segments with F0 > 750 Hz among them
11% are hyper-phonic.
The hig hest ave rage perce ntage of hyper -phonic cries is
found i n the ca tego ry of neu rologi cal pr oble ms (asphy xia,
microcephaly-IUGR) and also the highest average per-
centage of high pitched cries with 750 < F0 < 1000 Hz is
found in the category of neurological problems (micro-
cephaly-IUGR).
7. Conclusions
This study mostly deals with characterization of healthy
and pathologic newborn’s cry according to the modes of
cry as hyper-phonation, phonation, and high-pitched cry.
The conclusion from this work is that there are clear
differences in frequency characteristics of healthy and
pathologic cries. This difference can be used in pediatric
diagnosis. The results obtained are very encouraging
because they are consistent with spectrographic studies
of cryin g ne wborns [1,2,10].
This work is still in progress. The results obtained by
using different modes of cry as discriminative characte-
ristics for healthy and pathologic newborn’s cry can be
improved using other acoustic characteristics cited in the
literature in association with severe medical conditions.
More significant results can be expected using the de-
veloped tool on a larger database with a greater variety of
pathologies and more subjects for each pathology.
8. Acknowledgements
We would like to thank Dr. Barrington and members of
neonatology group of Saint-Justine Hospital in Montreal
(QC) for their dedication of the collection of the Infant’s
cry database. This research work has been funded by a
120.00%
100.00%
80.00%
60.00%
40.00%
20.00%
0.00%
30.00%
25.00%
20.00%
15.00%
10.00%
5.00%
0.00%

Y. KHEDDACHE, C. TADJ
276
grant from the Bill & Melinda Gates Foundation through
the Grand Challenges Explorations In itiative .
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