various noise can cause the wrong diagnosis due to bereavement of information. Some
problems that arise in ECG signal meas urement are due to noise such as baseline
wandering which is also usually accompanied by high-frequency noise components.
Baseline wandering can arise due to respiration and sweat that affects the parameters of
the electrode such as impedance. High-frequency noise components are caused by
movement of the body during the procedure.
Welfare of the fetus is the prime concern in pregnancy. Though the fetal mortality
rate [2] has decreased in developed countries, it is still a grave issue in developing and
underdeveloped nations. Genetic diseases always pose a large looming threat on the
fetus. Congenital malformations, membrane complications, malaria, and pre-eclampsia
are some of the disease responsible for fetal deaths. In a study in England and Wales in
the year 2007, it was found that congenital anomalies are the second highest cause of
infant deaths [3]. Bradycardia [4] has led to the invention of the micropacemaker [5]
which when used in a fetus helps forestall the need for exigent removal from its womb
in case of any medical emergency.
There are many ways to monitor the fetus using techniques like ultrasound which is
based on the usage of sensors. Non-stress test and contraction stress test are also other
ways of externally monitoring the state of the fetus. Presumptuous methods like
abdECG also help in relatively accurate measurement. Fetal ECG (fECG) is obtained
using electrodes which are planted on the head of the fetus. Such a prying procedure is
very cumbersome and invasive, which calls for the requisite for procedures that are
non-invasive. Observation of the fECG can help in having an insight of ailments and
anomalies that could be present in the fetus. One of the latest developments is the use of
Raspberry Pi microcontroller to monitor fECG [6]. There is various noise usually
present in the ECG that can arise from various sources such as interference of the
power line, noise due to contact established between electrodes, electrosurgical noise,
instrumentation noise and electromyography (EMG) noise that occurs due to muscle
movement in the vicinity of the heart. Since the fetus is present near the abdomen, there
is the possibility of much clamor that can occur due to the position and movement of
the fetus. The abdomen is in an anterior part of the body which contains important
organs like stomach and liver.
The abdominal muscles present abet in the process of breathing as adjunct support.
During this process, there is disturbance because of the process of respiration as there is
the movement of abdominal muscles present near the electrode. This neighboring signal
gets acquired as a part of the reading and is more prominent when compared to the actual
signal obtained from the abdomen . The noise created due to these such as high-frequency
noise components due to muscle movement and the wandering of the baseline have to be
addressed. Electromyography noise arises due to muscle movement that can affect the
changes in fECG especially if it occurs adjacent to the heart of the fetus. These noises are
inevitable and induce fallacious results. Wandering of the baseline can occur due to
improper placement of electrodes and this results in the ECG wave wandering above and
below the reference due to variation in amplitude. Some of these disturbances cause the
signal to get lost amidst these undesirable perturbations. These problems need to be
adhered to as the welfare of the fetus depends on it amidst pregnancy. This demands for
elementary met hods to deal with it. The paper has been fabricated in the following order:
Sect. 2 provides an accord about the literature survey that gives requisite background
4 J. Joseph et al.