Previous studies have shown that highly educated women are more likely to realise their fertility aspirations, or experience a faster progression to a higher order birth, compared to lower educated women. This is often explained by improved economic or social resources among the higher educated. However, it is unclear whether educational differences in health behaviours may also contribute to these differential fertility outcomes. In this study, we use data from Waves 1-7 of the UK Longitudinal Household Study, combined with data from the Nurse Health Assessment from Wave 2 to estimate couples' likelihood of experiencing additional childbirth within six years. A discrete-time event history model is employed to analyse the transition to a higher order birth, while accounting for both partners' level of education as well as smoking patterns and body mass index. We find that couples in which the female partner is highly educated are more likely to experience childbirth within six years compared to others. In addition, female smoking is negatively associated with the likelihood of childbirth, while no significant effect has been found for male health factors. Female health indicators explain some of the variation in fertility outcomes for women with lower secondary education compared to degree-educated women. However, education remains a significant predictor of the transition to higher order births, also after accounting for male and female health indicators. It is therefore important to consider both socio-economic and health factors in order to understand variations in fertility outcomes.
Keywords: BMI; education; fertility; health indicators; smoking.