Assessment and Management of Labour

Overview

In understanding labour, it is important to talk about women who are actually in labour. This means a correct diagnosis. Efficient uterine action is the key to normality in labour and the correct diagnosis of labour is the most important single decision. Safety and quality in labour is achieving efficient uterine action and simultaneously ensuring fetal and maternal wellbeing. Simplicity and consistency are the keys to success.

Nulliparous labour is completely different to multiparous labour, and spontaneous labour must be differentiated from induced labour (see Chapter 7 ). Single cephalic pregnancies must be distinguished from breech and multiple pregnancies and preterm labour from term labour.

The singleton cephalic nulliparous woman at term in spontaneous labour represents the key challenge and the most significant experience to the woman and her family. This is also the group of women in whom there is most variance in management, outcome and emotional experience. The singleton cephalic multiparous woman (without a previous caesarean uterine scar) at term in spontaneous labour is the other main group of women and the contrast between the two must never be forgotten.

With these principles in mind, a rational approach to the care of women in labour can be developed.

Antenatal Preparation for Labour

The better prepared and more confident a woman and her partner are before labour and delivery the better the effect on every aspect of her outcome, both physically and emotionally. Reassurances should be given that continuous, sympathetic and informed support will be forthcoming and that labour will not be allowed to last for too long. Preparation should be specific about how the diagnosis of labour is made and the importance of the part the mother has to play in the second phase of the second stage of labour (pushing phase). The graphic representation of labour on the partogram should be explained so that the woman is aware of the progress of her labour. The common events that take place in labour and the reasons for them should be explained. The difference between spontaneous and induced labour should also be emphasized and the methods used to ensure fetal wellbeing should be demonstrated. The relief of pain is discussed, with the emphasis on convincing the expectant mother she has nothing to fear on the basis that the duration of labour will be limited and she will never be left alone. The organization and planning of antenatal preparation is crucial and must be credible. Nulliparous and multiparous women should have separate preparation for their labours.

Management of the Labour Ward

When discussing labour, emphasis is always placed on the management of labour. Less emphasis, if any, is put on the management of the labour ward. A well-organized labour ward is essential to provide the best care and achieve the most out of available personnel and equipment. The adequacy and best use of resources has to be continually challenged.

The predominant professional carer for the woman and fetus in labour should be the midwife but they, together with obstetricians, paediatricians and anaesthetists, must integrate their expertise to provide the best care for each woman. Each professional must have their own clinical responsibilities, but lines of communication must be clear between professional groups and between junior and senior staff.

Assessment of the Woman Before Labour

Much is written about defining high- and low-risk women before labour. This is important, but the purist view on labour would be that most women are healthy and have well-grown babies before going into labour. Once in labour the principles of labour remain the same and abnormalities of labour relate most commonly to poor progress.

Diagnosis of Labour

‘If the os uteri remains close shut, it may be taken for granted, that the woman is not yet in labour, not withstanding the pains she may suffer’. William Smellie, A Treatise on the Theory and Practice of Midwifery. London. D Wilson; 1752:180.

The most single important aspect about labour is the diagnosis. In most labours there is usually little doubt.

The diagnosis of labour is made by history and examination. The woman will present with a history of regular, painful intermittent contractions. The frequency, length and strength of the contractions may vary and be subjective. A history of ruptured membranes and loss of the mucous plug is strongly supportive. Cervical effacement and dilatation on vaginal examination confirms the diagnosis.

The cervix in nulliparous and multiparous women is different. The nulliparous cervix is tubular shaped. The multiparous cervix is of comparable size but is cone shaped. The length of the cervix should be recorded in centimetres and the cervix in nulliparous women should not be considered to be ‘dilated’ until effacement (complete thinning) of the cervix has taken place ( Fig. 8.1 ).

There is no exact formula for the confirmation of the diagnosis of labour. In practice it represents a decision to commit a woman to delivery. Parity and gestation should be taken into consideration but a fixed cervical dilatation as a prerequisite for the diagnosis of labour may be clinically inappropriate. Error in diagnosis can occur when women were either wrongly diagnosed in labour when they were evidently not, or a missed diagnosis of labour when the woman returns fully dilated within a few hours. The difficulty arises more commonly in nulliparous women and has greater implications than in multipara. Occasionally the nulliparous woman may return completely demoralized and with an exhausted uterus; so that a labour that may have benefited from early assistance instead results in a prolonged labour with subsequent short-term and long-term consequences.

The diagnosis of labour is therefore crucial and also ensures that, right or wrong, a prospective decision is always made, either accepting the diagnosis of labour or rejecting it. The ‘intention to treat’ principle is paramount in labour and delivery in order to assess practice. Otherwise it is impossible to audit results, and standards cannot be set. Occasionally, deferring a decision for an hour is appropriate but encouraging indecision on a labour ward in principle is counterproductive.

‘The most important single issue of care in labour is diagnosis. When the initial diagnosis is wrong, all subsequent care is likely to be also wrong’. Kieran O’Driscoll

The quality of decision-making can only be assessed by continuous audit looking at length of labour, oxytocin and caesarean section rates within the Ten Group Classification System (see ).

Care of the Mother and Fetus

The woman’s general condition should always be checked at the beginning of labour, including general observations and urinalysis. Confirmation of the frequency, length and strength of the uterine contractions, the lie of the fetus, the presentation and descent of the head into the pelvis is carried out by abdominal examination.

Fetal wellbeing is confirmed by assessing the size of the baby; the colour, quantity and consistency of the liquor gives information regarding the condition of the fetus prior to labour and how it may respond to labour. The liquor may become meconium stained during labour, signifying possible fetal compromise. Amniotic liquor can only be assessed if the membranes have spontaneously or artificially been ruptured. The fetal heart rate may be monitored either by Pinard stethoscope, hand-held Doppler or continuous electronic monitoring.