• Open Access

Smoking during pregnancy – need for consistent Public Health data in Australia

Authors


Correspondence to: Dr. Divey Rattan, 305 Edith Cavell Building, School of Population Health, University of Queensland – Herston Campus, Herston Road, Herston. Queensland 4006; e-mail: diveyrattan99@yahoo.com

Maternal smoking remains one of the most common preventable causes of infant morbidity and mortality.1 In addition, pregnancy is a natural window for smoking cessation,2 and this has led to the suggestion that support for smoking cessation and relapse prevention needs to be as routine in antenatal care as the measurement of blood pressure.3 Quality Australian data documenting rates of tobacco consumption by women during various stages of pregnancy are not currently available.4 While there is a specification for perinatal data elements for mandatory collection and reporting at a national level, the Perinatal Minimum Data Set6 (NMDS) has no data element for smoking during pregnancy and there is no national agreement on collection of data on smoking during pregnancy.4

In Australia, five jurisdictions collect data on smoking during pregnancy; however, the definitions they use differ. The Australian Capital Territory and New South Wales use two questions – (1) did the mother smoke during pregnancy; (2) average number of cigarettes smoked per day during the second half of the pregnancy. Western Australia asks whether the mother smoked during pregnancy. South Australia collects data on – (1) smoking status at the first antenatal visit; (2) average number of tobacco cigarettes smoked per day in the second half of pregnancy. The Northern Territory has a question on smoking consumption at the first antenatal visit and at 36-weeks gestation. Given the different questions asked in the five jurisdictions, comparisons between states and territories are difficult and there is no national agreement.

In Australia, the two main sources of data collection for smoking during pregnancy are the National Drug Strategy Household Survey7 (NDSHS) and the National Perinatal Data Collection8 (NPDC). Both have certain limitations when it comes to collecting data on smoking during pregnancy. The NDSHS7 (2007) asks about (1) self-reported smoking status in last 12 months when subjects were pregnant or breastfeeding; and (2) whether the subjects were advised to quit smoking during the last 12 months when they were pregnant or breastfeeding. The NDSHS7 (2007) has only two questions around smoking during breastfeeding (not pregnancy) and does not distinguish the stage of pregnancy/post-partum, parity, quantity or pattern of smoking, all of which are an integral component to any tobacco control policy.5 Their report suggests that smoking around pregnancy occurs in about 12% of pregnancies in Australia, but again, these figures have to be interpreted with caution as smoking during breastfeeding is different from smoking during pregnancy. In contrast, the data for Australia derived from the NPDC8 for births in 2006 states that 17.3% of women (excluding Victoria) smoke at all during pregnancy.4 NPDC8 does not contain information on all possible confounders for smoking during pregnancy. For example, it does not contain information on educational level, socioeconomic status, paternal smoking status, private health insurance status and maternal medical conditions.4

In comparison to the situation in Australia, the US has the Pregnancy Risk Assessment Monitoring System9 (PRAMS) which is an ongoing, state-and population-based surveillance system designed to monitor selected self-reported maternal behaviours and experiences that occur before, during and after pregnancy among women who deliver a live-born infant. PRAMS9 employs a well-organised data collection methodology; up to three self-administered surveys are mailed to a sample of mothers, and non-responders are followed up with a telephone interview.6 If we compare the methodology and extent of information collected through the Australian NMDS6 and NDSHS7 (2007) with PRAMS9, Australia lags on both fronts. In terms of extent of information, a comparison is shown in Table 1. It is clear that NMDS6 and NDSHS7 (2007) are deficient in terms of information on smoking before pregnancy, quitting status during pregnancy, and smoking or relapse after delivery. We believe that five standard measures should be specified as a minimum by the NMDS6 and included in the data collection for Australia. These are:

Table 1.  Comparison of US data collection system (PRAMS) with Australian systems.
Standard MeasuresUS DataAustralian Data
 PRAMS9NMDS6NDSHS7
Smoking during 3 month before pregnancy
Smoking During Pregnancy
Quitting smoking during pregnancy among women who smoked before pregnancy
Smoking after delivery
Relapsing to smoking after delivery among women who quit smoking during pregnancy
  • • Smoking during the three months before pregnancy.
  • • Smoking during pregnancy.
  • • Quitting smoking during pregnancy among women who smoked before pregnancy.
  • • Smoking after delivery.
  • • Relapsing to smoking after delivery among women who quit smoking during pregnancy.

As shown in the table, Australian data collection (both NMDS6 and NDSHS7) provide information on only one standard measure.

In Australia, valuable information could be generated on perinatal health topics by following the example set by PRAMS9 and can provide much needed adequate and consistent quality national data on smoking during pregnancy. Australian data collection targeting smoking during pregnancy can be further improved by administering questions that provide information on all five standard measures as shown in Table 1. We recommend that these measures be advocated by NMDS6, thus standardising data collection for smoking during pregnancy in Australia.

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