CTG for monitoring contractions

The conventional CTG will tell you how frequently the mother is getting contractions, how regular they are and how long each contraction lasts. It also allows the doctors to analyze what effect the contractions are having on the fetal heart pattern. It does not tell how strong the contractions are. This still requires the ever-dependable hand of the midwife - by feeling. Of course, in some cases, even this does not work very well especially in the case of a markedly obese woman.

For some years now, there have been gadgets available which can be placed inside the womb itself to monitor the strength of contractions. They are supposedly useful in cases where there is a perceived risk of uterine rupture such as in cases where there was a caesarean section or surgery on the womb in the past.

Unfortunately, they have been rather disappointing in the sense that, while they monitor uterine contraction strength very well, they do not seem to confer any tangible benefit over the conventional CTG. They are also expensive, delicate and cumbersome to use. They are used where necessary but their place in mainstream delivery suite practice is debatable.

Alternatives to a CTG

Before the advent of electronic fetal monitoring, a simple device called a Pinard fetal stethoscope was the standard equipment in monitoring the fetal heartbeat. It is still used in some labor wards in conjunction with a CTG but it is largely of historical significance now.

The one development that seems to hold promise is the so-called ‘near-infrared spectroscopy’. This involves attaching a soft pad on the fetal scalp, from which a special light is beamed into the fetal brain. The pattern of absorption of this light by the blood can be analyzed to identify which babies are getting insufficient oxygen to the brain and therefore in need of intervention. The technology has been undergoing tests for perfection for a number of years, now. As with all new developments, it is best to wait until it is squarely on the table before singing praises.

Continuous electronic fetal monitoring

Continuous CTG monitoring is quite controversial. There is strong evidence that continuous monitoring is not for everyone, yet many units continue to do this. In a labor where there is no apparent risk factor (low-risk pregnancy), intermittent monitoring is just as good. It has the advantage of not curtailing the woman's mobility for hours on end.

Of course, those women whose pregnancies have some risk factors (such as fetal growth restrictions, pre-eclampsia and diabetes) need continuous monitoring. It remains a fact that the majority of pregnancies are low-risk and the restriction of continuous monitoring for them is unjustified.

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The greatest drawback of continuous CTG monitoring is the fact that the expectant mother will have to be strapped to the machine for hours on end, severely limiting her mobility.