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Is precarious employment associated with women remaining childless until age 35 years? Results from an Australian birth cohort study.

STUDY QUESTION
Does time in casual employment (while not studying full time) affect the likelihood of a woman having a child by age 35?


SUMMARY ANSWER
Duration of time spent in casual employment is associated with an increased likelihood of childlessness at age 35 years, irrespective of socio-economic background as indicated by educational level.


WHAT IS KNOWN ALREADY
Precarious employment conditions have become increasingly prevalent in recent decades in Western countries. The relationship between precarious employment conditions and age at first childbirth has been examined in several European countries with varying results.


STUDY DESIGN, SIZE, DURATION
A retrospective cross-sectional component (n = 663) was added to an existing study based on a cohort of women born during 1973-1975. An event history calendar instrument was used to obtain data regarding a range of life domains over a 20-year period.


PARTICIPANTS/MATERIALS, SETTING, METHODS
Using data from the Life Journeys of Young Women Project carried out in Adelaide, South Australia, Cox proportional hazards models were applied to investigate the research questions.


MAIN RESULTS AND THE ROLE OF CHANCE
The likelihood of childbirth by around age 35 was reduced for every year spent in casual employment, irrespective of socioeconomic status, partner's education and parents' birthplace. The likelihood was reduced by 8, 23 and 35% for 1, 3 and 5 years spent in casual employment, respectively.


LIMITATIONS, REASONS FOR CAUTION
Women with longer employment histories (and greater age at first birth) had more opportunities for errors in recall, but it is unlikely that such errors were systematic and led to bias in the results. While we included variables reflecting partner's education and length of time with a live-in partner, partner's employment histories were not taken into account.


WIDER IMPLICATIONS OF THE FINDINGS
Duration of time spent in casual employment is associated with an increased likelihood of childlessness at age 35 years, and this association is present across the spectrum of socioeconomic status. We suggest that upstream labour market reforms could be considered in order to reduce barriers to childbearing.