Background: A high proportion of unwanted or unplanned pregnancies may be alcohol-exposed due to contraception failure or non-use. Nevertheless, data on contraception and alcohol use in the context of the risk of alcohol-exposed pregnancies are sparse.
Objectives: To describe contraception use and alcohol consumption in sexually active non-pregnant women and investigate the factors associated with less effective contraception methods.
Study design: A cross-sectional national survey of women aged 18-35 years.
Methods: Data from non-pregnant women who were sexually active (n = 517) were analysed. Descriptive statistics were used to report demographics, consumption, and contraception measures. Logistic regression was used to investigate the factors associated with less effective contraception among drinkers.
Results: The majority of participants were younger (46%), of NZ European ethnicity (78%), not in a permanent relationship (54%), with some or completed tertiary education (79%), employed (81%) and not users of the community services card (82%). Twenty-five percent of women were smokers, 94% consumed alcohol, and 72% binged at least 'monthly or less'. Most women used the pill (56%), and 20% of drinking women were using a contraception method with a 10% or more annual failure rate after 1 year of use. Women who binged 'weekly or more often' had similar odds of using less effective contraception as women who 'never' binged (p > 0.05). Younger Māori or Pacific women (odds ratio = 5.99; 95% confidence interval of odds 1.15-31.2; p = 0.033) and women who had no tertiary education (odds ratio = 1.75; 95% confidence interval of odds 0.00-3.06; p = 0.052) had higher odds of using less effective contraception.
Conclusion: With 20% of women at risk of an alcohol-exposed pregnancy, public health measures to address alcohol consumption and the effective use of contraception are critical to reducing the risk for alcohol-exposed pregnancies in NZ.
Keywords: New Zealand; alcohol-exposed pregnancy; binge drinking; effective contraception use; periconceptional drinking.