Saturday, 20 June 2009

Sobering statistics from the National Health Survey- part 3

The national health survey, A Picture of Australia's Children 2009 is one again enlightening reading. This time I'll focus of pregnancy.

Teenage pregnancies

The stats about teen pregnancies:

In 2006:
􀁴􀀁 Around 11,900 infants were born to teenage mothers—a rate of 17 live births per 1,000
females aged 15–19 years. Births to teenage mothers accounted for 4.5% of all live births.
􀁴􀀁 Of teenagers who gave birth, 82% were first-time mothers (or to put it another way, 18% or just under 1 in 5 teenage mothers had at least two children)

􀁴􀀁 The Indigenous teenage birth rate was 5 times the non-Indigenous rate—80 births per 1,000, compared with 15 for non-Indigenous teenagers
􀁴􀀁 The teenage birth rate increased with increasing remoteness, with teenage girls in remote and very remote areas being 5 times as likely to give birth as their peers in major cities (63 per 1,000 compared with 13).
􀁴􀀁 There was no statistically significant difference in teenage birth rates between those in the richest and poorest areas.

How do Australia’s teenage birth rates compare internationally?

Australia’s teenage birth rate ranked 20th out of 30 OECD
countries in 2002:

  • Korea 2.7 births per 1,000 teenage females

  • Switzerland 5.5

  • Japan 6.2

  • OECD average 17

  • Australia 18

  • United States 43

  • Turkey 49

  • Mexico 51.

Smoking and drinking during pregnancy


Smoking during pregnancy is a significant risk factor for the mother and her unborn baby. Tobacco smoke interferes with normal fetal development by restricting oxygen flow through the placenta and exposing the developing fetus to numerous toxins. This increases the risk of spontaneous abortion and ectopic pregnancy, and can result in health problems for the newborn,
including low birthweight, intrauterine growth restriction, prematurity, placental complications, birth defects, lung function abnormalities and respiratory symptoms, and perinatal mortality (Jauniaux & Burton 2007; Julvez et al. 2007; Milner et al. 2007).
Low birthweight and short gestation are the most common short-term problems for infants whose mothers smoked in pregnancy, and are associated with increased perinatal morbidity and mortality, as well as adverse health outcomes throughout life...

Lower levels of exposure to cigarette smoke are associated with improved health outcomes for infants—reducing cigarette smoking to eight cigarettes a day significantly improves birthweight,
while quitting smoking within the first 20 weeks of pregnancy results in birthweight similar to that of infants of non-smoking mothers (Chan & Sullivan 2008; Hoff et al. 2007). Conversely, mothers who smoked more than 10 cigarettes a day have infants of significantly lower birthweight (Chan & Sullivan 2008).

The effects of smoking during pregnancy are not restricted to the perinatal period but persist into infancy and childhood. Smoking during pregnancy has been found to be associated with SIDS and childhood conditions such as asthma, obesity, lowered cognitive development and psychological problems (Button et al. 2007; Julvez et al. 2007).

A number of maternal characteristics are associated with smoking in pregnancy. Rates of smoking in pregnancy are higher among teenage mothers, lone mothers, Aboriginal and Torres Strait Islander mothers, and mothers with lower levels of educational attainment and of low socioeconomic status (Laws et al. 2006). Women continue to smoke during pregnancy for many
reasons such as addiction, and social and economic pressures, as well as the lack of understanding of the consequences of smoking during pregnancy (Hoff et al. 2007; OBGYN & Reproduction Week 2008).

In 2006, excluding data for Victoria:
􀁴􀀁 One in six (17%) women who gave birth reported smoking during pregnancy, and the
rate has remained fairly stable since 2001.
􀁴􀀁 Smoking in pregnancy was most common among teenage mothers (42%), and decreased with increasing maternal age to between 11% and 12% among mothers aged 30 years and over.
􀁴􀀁 Infants whose mothers smoked during pregnancy were twice as likely to be of low birthweight (11% compared with 5% for those who did not smoke) and 60% more likely to be pre-term at less than 37 weeks than mothers who did not smoke.

In 2006, excluding data for Victoria:
􀁴􀀁 More than half (52%) of Indigenous mothers reported smoking during pregnancy—more than 3 times the rate of non-Indigenous mothers (16%).
􀁴􀀁 Mothers in remote areas were more than twice as likely to have smoked during pregnancy compared with mothers in Major cities (32% and 13%, respectively).
􀁴􀀁 Mothers in the poorest areas were over twice as likely to have
smoked during pregnancy than those in the richest areas (27% and 6% respectively).


Maternal alcohol use during pregnancy is associated with adverse perinatal outcomes. Alcohol readily crosses the placenta and is a well-known teratogen (that is, it can cause birth defects). Research has shown that maternal drinking at high levels during pregnancy can cause:

  • miscarriage

  • stillbirth and premature birth

  • growth retardation

  • fetal alcohol syndrome
  • pseudo-Cushing’s syndrome
  • alcohol withdrawal in the newborn
  • alcohol-related birth defects, and
  • neurological, cognitive and behavioural problems
    (NHMRC 2001; Peadon et al. 2007; Tai et al. 1998 cited
    in AIHW: Ford et al. 2003).

Exposure to alcohol in the uterus is the leading cause of birth defects and mental
retardation among children (Kumada et al. 2007). Fetal alcohol spectrum disorder is an umbrella term that describes a range of conditions that can occur in children exposed to alcohol before birth. Fetal alcohol spectrum disorder includes fetal alcohol syndrome,
alcohol-related birth defects and alcohol-related neurodevelopmental disorders. These conditions are entirely preventable (Peadon et al. 2007).

Fetal alcohol syndrome
Fetal alcohol syndrome (FAS) is the most severe alcoholrelated disorder among children (Kumada et al. 2007). FAS refers to a pattern of abnormal features associated with
the use of alcohol during pregnancy. The characteristic feature of FAS include prenatal and/or postnatal growth estriction, characteristic facial features and central
nervous system abnormalities (for example, neurological abnormalities, developmental delays, behavioural dysfunction and learning difficulties). Children with FAS experience lifelong problems, including learning difficulties and disrupted education, increased rates of mental illness, drug and alcohol problems, inappropriate sexual behaviour, unemployment and contact with the law (Streissguth et al. 2004 cited in Peadon et al. 2007).

Rates of FAS in Australia, and around the world, are likely to be underestimated, due to difficulties in identifying and managing the condition, and fears of stigmatisation
for the child and family (Elliott et al. 2006b). In Australia, there was a significant increase in the number of children reported with FAS to the Australian Paediatric Surveillance
Unit each year from 2001 to 2004 (Elliott et al. 2007). Higher rates of FAS occur in Indigenous communities compared with non-Indigenous communities (Elliott et al. 2006a). Many children affected by FAS are in foster care, while many others have an affected sibling, which suggests
missed opportunities for prevention (Elliott et al. 2006a).

Is there a safe level of alcohol consumption during pregnancy?
Damage to the fetus depends on the quantity, frequency and timing of alcohol consumption during pregnancy and is influenced by maternal factors. Drinking heavily or to intoxication poses the greatest risk to the developing fetus, but some recent studies suggest that even low levels of
alcohol consumption (such as one or two drinks per week) may adversely affect neurodevelopmental and behavioural outcomes (NHMRC 2009). These effects can be prevented
by abstaining from alcohol during pregnancy.

High levels of alcohol consumption in the first trimester can cause facial and brain malformations, while consumption during the third trimester is highly related to damage to the areas of the brain responsible for sensory perception, motor control, short-term memory, spatial
navigation and executive functioning (such as cognitive behaviour, personality expression and moderation of appropriate social behaviour) (Riley & McGee 2005). The relative risk of drinking during pregnancy or breastfeeding (compared with not drinking) has not been determined across a range of drinking levels. Hence, a safe (‘no-effect’) level has not been established on a
population basis. Furthermore, individual factors mean that actual risks vary considerably from one person to another....

How many women consume alcohol while pregnant?

The National Drug Strategy Household Survey asks women whether they consumed alcohol while pregnant, while breastfeeding, or while pregnant and breastfeeding in the previous 12 months. The survey also asks about changes in alcohol consumption due to pregnancy or breastfeeding: whether women abstained from alcohol, reduced alcohol consumption or made no change to alcohol consumption.

􀁴􀀁 Of those who reported that they did consume alcohol during pregnancy, the majority (94%)
reduced their consumption, while a small proportion (6%) drank the same or more. The National Drug Strategy Household Survey also found that women were likely to reduce their use of
tobacco or marijuana when they were pregnant. Of those women who were pregnant in the 12 months before the survey, 10% used tobacco while pregnant and 3% used marijuana, down from rates of 18% and 9%, respectively, when the same women were not pregnant. The 2006 Victorian Child Health and Wellbeing Survey collected information from women about
their consumption of alcohol during pregnancy. The survey found that for children aged under 2 years:
􀁴􀀁 Three in five (61%) had mothers who said they drank alcohol early in their pregnancy before they knew they were pregnant.
􀁴􀀁 One in five (21%) had mothers who reported that they had drunk more than 4 standard drinks in one day before they knew they were pregnant, and 8% had mothers who said they drank to this level at least once a week before becoming aware of their pregnancy.
􀁴􀀁 When women knew they were pregnant they were less likely to drink alcohol and very unlikely to drink more than 4 standard drinks in one day. One-third (34%) of children had mothers who drank alcohol at least once in early pregnancy after becoming aware
that they were pregnant, and 31% had mothers who drank alcohol late in their pregnancy.

Environmental tobacco smoke in the home

Environmental tobacco smoke is one of the most hazardous environmental exposures for children. Tobacco smoke contains numerous toxic and cancercausing chemicals that increase the risk of adverse health outcomes for children, including SIDS, acute respiratory infections, middle-ear infection (otitis media), onset and increased severity of asthma, respiratory symptoms and slowed lung growth (CDC 2007; WHO 2007).

Children with parents who smoke are also more likely to take up smoking later in life (Kestila et al. 2006). Infants and children are particularly vulnerable to the effects of environmental tobacco smoke because they have less developed respiratory, immune and nervous
systems, and have limited control over their exposure. These vulnerabilities combined with exposure to tobacco smoke in enclosed spaces, such as the home or car, mean that children can be exposed to high levels of environmental tobacco smoke in a short period of time. In homes where someone smokes inside, children have higher levels of cotinine, a biological marker for exposure to tobacco smoke, than children not exposed to tobacco smoke in the home (CDC 2007). Children travelling in a car with someone smoking are also at risk, even if the windows are down (Sendzik et al. 2008; Sly et al. 2007).

There is no safe level of exposure to environmental tobacco smoke and adults can do much to reduce or prevent a child’s exposure, particularly by not smoking in the home or car. The benefits of reducing children’s exposure to tobacco smoke in the home include improved
health and school performance, reduced absenteeism from school, reduced uptake of smoking, and less frequent smoking among children who smoke (NDS 2002).

In 2007, of households with dependent children aged 0–14 years:
􀁴􀀁 About 8% of households had someone who smoked at least one cigarette, cigar or pipe of
tobacco inside the home per day.
􀁴􀀁 Children were less exposed to tobacco smoke in the home than in 1995—children in almost one-third of households were exposed to tobacco smoke in the home in 1995, compared with 8% in 2007.

This decline has coincided with an increase in the proportion of households where someone smoked only outside the home (from 17% to 29%).

􀁴􀀁 The proportion of households with children where no one smoked regularly at home
increased from 52% in 1995 to 63% in 2007, consistent with the general decline in smoking
prevalence among the Australian population.

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