In most developed countries the maternal death rate remained about the same from 1850 to 1934, when it began to fall. In the period before the mid-1930s it was about 500 per 100 000; by the mid-1980s, in many industrialized countries it had fallen to fewer than 10 per 100 000 maternities (Fig. 25.1). The initial fall was due to the control of infections by better obstetric care and the introduction of antibiotics. The second factor was that most women availed themselves of good-quality antenatal care, which enabled complications to be detected early and treatment to be offered, usually in well-equipped hospitals staffed by trained medical attendants. Blood became increasingly and quickly available from blood banks, which considerably reduced the deaths due to haemorrhage. Sociological changes have also occurred in the past 60 years: fewer women now have more than three children, and most have their pregnancies before the age of 35. Higher parity and advancing age increase the risk of maternal death. There has been a small rise in the maternal mortality rates in some developed countries in the last decade. Whether this is due to women with medical conditions that previously precluded pregnancy having children, increasing maternal age, the rise in obesity or better ascertainment of cases is not clear.

Fig. 25.1 The secular trend of maternal mortality in Australia and the United Kingdom.

In the developing countries the maternal mortality rate is much higher. In sub-Saharan Africa it averages 600 per 100 000 live births; in south Asia, 500 per 100 000 births; in southeast Asia and Latin America 300 per 100 000 live births. The reasons for these high rates are: frequent pregnancies, with short intervals between them; the resort to unsafe abortion performed in unhygienic surroundings; a relative lack of prenatal care and a lack of the perception of its value by poorly educated and poorly informed women; a lack of access to skilled medical help; and a lack of government support to make changes to the status, education and empowerment of women. Worldwide a woman dies every minute as a result of pregnancy.

Causes of maternal death

Several developed countries publish the results of confidential enquiries into maternal deaths at intervals of about 3 years. In these reports the causes of and contributing factors to the deaths are analysed and suggestions are made that might prevent such deaths occurring.

These reports have been published in the UK since 1952 and in Australia since 1965. The total direct and indirect deaths per 100 000 maternities had risen from 9.83 in the 1985–7 triennium to 12.45 in 2003–5. This may be due to underreporting in earlier years, but emphasizes that there is no room for complacency in modern maternity units in the developed world. The major contributing factors to suboptimal care are poor liaison between healthcare professionals, failure to appreciate the severity of the condition, and wrong diagnosis. Table 25.1 shows the most common causes of death, Table 25.2 the percentage associated with substandard care, and Figure 25.2 illustrates the changes with time in the major causes of maternal death in England and Wales. Maternal deaths can be reduced further, particularly those associated with anaesthesia, ectopic gestation, sepsis and pulmonary embolism.

Table 25.1 Major causes of maternal deaths per million maternities in the UK 1985–2005

CAUSE	DEATHS
Direct
Thrombosis and thromboembolism	14–22
Pre-eclampsia and eclampsia	7–12
Haemorrhage	3–9
Amniotic fluid embolus	4–8
Early pregnancy (ectopic and miscarriage)	5–8
Sepsis	4–9
Anaesthetic	1–3
Indirect
Cardiac	8–23
Psychiatric	4–9
Malignancies	3–5
Coincidental	12–26
Late	10–40

Table 25.2 Direct and indirect maternal deaths United Kingdom 2003–2005 assessed as having substandard care

CAUSE OF DEATH	% WITH SUBSTANDARD CARE
Direct
Thromboembolism	56
Pulmonary embolism	67
Cerebral embolism	13
Pre-eclampsia/eclampsia	72
Haemorrhage	59
Amniotic fluid embolism	41
Early pregnancy	79
Sepsis	78
Anaesthetic	100
All direct	64
Late direct	55
Indirect
Cardiac	46
Psychiatric	42
Malignancy	50

Fig. 25.2 Main causes of maternal deaths directly due to pregnancy or childbirth (England and Wales) per million maternities.

PERINATAL MORTALITY

The death of a fetus in utero or its death in the neonatal period causes much distress to the parents and is a measure of the quality of obstetric care.

Before perinatal mortality can be discussed, some terms need to be clarified.

• Live birth is the birth of an infant, regardless of maturity or birthweight, who breathes or shows any other signs of life after being born.

• Stillbirth or fetal death is the birth of an infant of at least 20 weeks’ gestation or if gestation is unknown weighing at least 400 g, which shows no signs of life after birth.

• Early fetal deaths equate to abortions, and intermediate fetal deaths are those occurring between the 22nd and 27th completed gestational weeks, the fetus weighing 500–999 g (also called stillbirth).

• Late fetal death is fetal death at 28 completed weeks of gestation and over. The fetus usually weighs 1000 g or more (also called stillbirth).

• Neonatal death is the death of a liveborn infant, less than 28 completed days after birth, of at least 20 weeks’ gestation or if the gestation is unknown weighing at least 400 g. Neonatal deaths can be divided into two groups: early neonatal deaths and late neonatal deaths.

• Early neonatal or postnatal death is the death of a liveborn baby in the first 7 completed days (168 hours) of life.

• Late neonatal death is the death of a liveborn infant after 7 completed days but before 28 completed days of life.

Perinatal death is a stillbirth (or fetal death) or neonatal death

The definitions of the mortality rates and ratios is summarized in Box 25.2. For international comparison the WHO perinatal mortality rate refers to all births of at least 1000 g birthweight or when the birthweight is unknown, of at least 28 weeks’ gestation and neonatal deaths occurring within 7 days of birth. In many developed nations the PMR is around 6 per 1000 births. In the few developing countries that have been able to publish reasonably reliable data the PMR is between 35 and 55 per 1000 births.

Box 25.2 Definitions of mortality rates and ratios

Social factors affecting the PMR

The most exact information about the effect of sociological factors on the PMR is obtained from the British Perinatal Mortality Surveys published in 1958 and 1970. All births occurring during 1 week and all singleton fetal deaths and neonatal deaths over a 3-month period were surveyed.

The findings were that:

• The lower the social class the higher the standard PMR, which rose from 7.5 per 1000 in social class 1 to 26.8 per 1000 in social classes IV and V.

• The mother’s age affected the PMR. It was highest among the infants of mothers younger than 17 years and older than 35 years.

• Women who did not avail themselves of antenatal care had 5–10 times the mean PMR.

• The management of the labour affected the PMR. One-third of the perinatal deaths were due to intrapartum anoxia alone or were associated with birth trauma. In some cases the intrapartum anoxia was a sequel to antepartum conditions, the fetus entering labour in poor health; in other cases, mismanagement of labour or the misuse of forceps damaged the baby which was either stillborn or died in the early neonatal period.

Analysis of perinatal mortality

Perinatal deaths are classified according to their aetiology and not by the immediate cause of death. The accurate determination of the specific factors leading to the neonatal death enables health professionals to identify correctable problems. The principal causes of perinatal deaths in Victoria, Australia are shown in Table 25.3.

Table 25.3 Causation of perinatal mortality: Victoria, Australia 2006

Reduction of perinatal mortality

Many of the measures that have been effective in reducing maternal deaths are also effective in reducing perinatal deaths. In addition, the provision of well-equipped, well-staffed neonatal intensive care units (NICU) will enable a number of low-birthweight babies to survive and grow.

MANAGEMENT OF FETAL INTRA-UTERINE DEATH

Clinical aspects

The mother notices that fetal movements have ceased and Doppler or ultrasound examination fails to detect any fetal heart activity. When she realizes that her baby has died the expectant mother is distressed and concerned that the dead fetus, if it remains in her uterus, will decay and cause infection. Medical problems are unlikely, at least in the first 3 weeks after the fetal death has been diagnosed. After this time, disseminated intravascular coagulation and hypofibrinogenaemia may arise, with potentially serious consequences to the woman.

Management

The parents need support, information, and their immediate questions answered. They should be offered bereavement counselling. They should be reassured that the dead fetus, if left in the uterus, will not cause any harm in the following 3 weeks, and that usually labour will start during this time. The woman may choose to await spontaneous labour or to have labour induced. The management of the labour should be discussed with her and she should be assured that she will be given analgesics to reduce or eliminate the pain of childbirth. If she and her partner wish to view and hold the fetus after delivery they should be made aware that it may be macerated, depending on when the death occurred.

If spontaneous labour has not started 3 weeks after the diagnosis, or if the woman chooses immediate treatment, labour is induced by prostaglandin E₂ vaginal pessaries or gel, as described on page 189. Alternatives are to prescribe mifepristone 600 mg/day for 3 days, misoprostol 100–200 μg 12-hourly for four doses, or the prostaglandin analogue sulprostone, 1 μg/min IV, until the fetus is expelled. Using any of these methods, 50% of women will expel the fetus in 12 hours and 90% in 24 hours.

If the woman chooses to await the spontaneous onset of labour, frequent blood checks should be made by observing the clotting time of the blood or by estimating fibrinogen levels.

Investigations

The basic investigations to determine the cause of death that should be offered are listed in Box 25.3. An autopsy should be offered, as the reason for the death is changed by the autopsy findings in up to 25% of cases. The findings can have significant implications for counselling and for the management of another pregnancy.

Box 25.3 Investigating a perinatal death