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. Quality care in labour is achieving efficient uterine action and simultaneously ensuring fetal and maternal wellbeing.

Nulliparous labour is completely different to multiparous labour and spontaneous labour must be differentiated from induced labour. 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. The singleton cephalic multiparous woman (without a previous 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 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 outcome 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

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 (thinning) of the cervix has taken place ( Fig 5-1 ).

Diagramatic representation of cervical effacement (a) and dilatation of the nulliparous and the parous cervix (b).

(Reproduced with permission from O’Driscoll K, Meagher D, Robson M. Active Management of Labour. 4th ed. London: Mosby, 2003.)

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 woman may return completely demoralised 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. 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 may be 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 10 groups.

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 fetus’s condition prior to labour and how it may respond to labour. The liquor may become meconium stained during labour, signifying possible fetal compromise. The fetal heart rate may be monitored either by Pinard stethoscope, hand held Doppler or continuous electronic monitoring.

Stages of Labour

Labour is divided into three stages. The first and second stages rely on anatomical criteria and this may be disadvantageous as labour is essentially a dynamic process. In normal labour the transition from the first to the second stages is of little clinical significance and the important events are the diagnosis of labour and the maternal urge to push. The importance of defining the first and second stages of labour becomes more relevant if the labour does not progress normally. Because normal labour can only be confirmed retrospectively, there is difficulty in defining exactly when a normal labour becomes abnormal and requires treatment. Indeed, this definition will be different depending on the gestation, the parity, and whether the pregnancy is singleton cephalic. It will also depend on what the initial dilatation of the cervix was at the diagnosis of labour.

The Partogram

The partogram for recording the progress of labour was introduced after the classical studies of Emmanuel Friedman in the USA and subsequently the pragmatic innovations of Hugh Philpott in Africa. Elements of Philpott’s partogram were incorporated into the current World Health Organization’s partogram ( Fig 5-2 ). Partograms vary but the important component is a graphical plot of the progress in labour to assist decision-making. This is emphasized in the partogram used in Active Management of Labour where no allowance for the latent phase is made ( Fig 5-3 ). The graphical plot is measured in centimetres dilated on the x axis against hours in labour on the y axis. The partogram records other information about labour events and labour outcomes contributing to the audit of labour and may exist in different colours for easy distinction between nulliparous and multiparous women. Carbon copies may be used so that copies of the partogram can be kept separately on the labour ward for inspection after the woman has delivered.

World Health Organization partograph.

Partogram used at The National Maternity Hospital, Dublin

(National Maternity Hospital, Dublin).

Spontaneous Onset of Labour and Favourable Predictive Factors

The most important aspect about the management of normal labour is the fact that there has been spontaneous onset. The risk of intervention is much less in spontaneous labour, and much less again in multiparous women (without a previous scar) than in other groups of women. A greater dilatation of the cervix at the time of diagnosis of labour and presentation to the delivery ward does not necessarily reflect the length of time in labour, but is more likely to reflect efficient uterine action especially when the history of contractions has not been long. This and engagement of the presenting part are good predictors of normal labour. On the contrary, a long history of contractions without onset of labour or only 1 cm dilated on admission are less favourable predictive factors as is labour at later gestations. This is especially true in nulliparous women where the requirement for artificial rupture of the membranes, oxytocin acceleration (augmentation), caesarean delivery and other interventions increase steadily from 37 weeks to 42 weeks.

Personal Attention

Personal attention in labour cannot be overemphasized and is undervalued in most delivery units. The fear of being left alone is common. It is important that a woman’s morale is maintained from the beginning of her labour. The longer her labour, the more difficult it is to achieve this; and the greater her loss of composure, the more difficult it becomes for her to recover it. The final result can be panic, from which the individual may never fully recover.

The solution is a commitment in each delivery unit to every expectant mother of continuous personal attention through labour. This can only be carried out effectively if there is a limitation on the duration of labour. The ability to provide continual personal attention is the best indicator of the quality of care afforded in any delivery unit and mothers regard it as the most important contribution to their care.

Although childbirth has long ceased to present a serious physical challenge to healthy women in western society, the emotional impact of labour remains a matter of common concern.