Objective: Study the association between the introduction of tobacco control policies in the Netherlands and changes in perinatal outcomes.
Design: National quasi-experimental study.
Method: We used Netherlands Perinatal Registry data (now called Perined) for the period 2000-2011. We studied whether the introduction of smoke-free legislation in workplaces plus a tobacco tax increase and mass media campaign in January 2004, and extension of the smoke-free law to the hospitality industry accompanied by another tax increase and media campaign in July 2008, was associated with changes in perinatal outcomes. We studied all singleton births (gestational age: 24+0 to 42+6 weeks). Our primary outcome measures were: perinatal mortality, preterm birth and being small-for-gestational-age (SGA). Interrupted time series logistic regression analyses were performed to investigate changes in these outcomes occurred after the introduction of the aforementioned tobacco control policies (ClinicalTrials.gov: NCT02189265).
Results: Among 2,069,695 singleton births, 13,027 (0.6%) perinatal deaths, 116,043 (5.6%) preterm live-births and 187,966 (9.1%) SGA live-births were observed. The policies introduced in January 2004 were not associated with significant changes in any of the primary outcome measures. A -4.4% (95% CI: -6.4 to -2.4; p < 0.001) decrease in odds of a SGA birth was observed after the policy extension in July 2008 to include a smoke-free hospitality industry, a further tax increase and another media campaign. This translates to an estimated over 500 cases of SGA being averted per year.
Conclusion: A reduction in SGA births, but not preterm birth or perinatal mortality, was observed in the Netherlands after extension of the smoke-free workplace law to include bars and restaurants, in conjunction with a tax increase and media campaign in 2008.