Ethnic differences in fertility and timing of role transition to parenthood have been the focus of extensive research. The present study examined the associations between ethnic identity and pregnancy/parenthood by age 20 among a longitudinal birth cohort of New Zealanders born in 1977. Those participants of sole Maori identity reported higher rates of both early pregnancy and parenthood than either non-Maori or those of Maori/other ethnic identity. Control for a range of socio-economic and family functioning factors reduced the magnitude of the associations between ethnic identity and pregnancy/parenthood. However, even after controlling for socio-economic and family functioning factors, sole Maori individuals were still at greater risk of pregnancy/parenthood by age 20. Similar results were found for an alternative measure of the extent of Maori identity. It was concluded that higher rates of early pregnancy/parenthood among Maori are associated with factors relating to cultural identity. However, the mechanisms by which cultural identity may be linked to early pregnancy/parenthood are unclear.
In recent years there has been considerable interest in ethnic differences in fertility rates in industrialised nations (Kollehlon 2003, Lindstrom 2003, Kaufman et al. 2007), with research showing that fertility rates and timing of role transition to parenthood by ethnic minorities are often at variance with those of the majority population (Coley and Chase-Lansdale 1998, Higginbottom et al. 2006, Whitley and Kirmayer 2008). Further research has examined the role of early age of parenting and parenthood in contributing to ethnic disparities between groups in industrialised nations (Singh et al. 2001, Hobcraft and Kiernan 2001, Robson and Berthoud 2006).
In New Zealand it has been well documented that women of Maori ethnicity are more likely to become parents at an earlier age than non-Maori women (Dickson et al. 2000, Woodward et al. 2001, Mantell et al. 2004, Statistics New Zealand 2004, Khawaja et al. 2006). For example, rates of teen pregnancy among young Maori are approximately four times higher those that of their non-Maori peers (Dickson et al. 2000, Bean 2005, Statistics New Zealand 2005, Ministry of Social Development 2008b). Between the years 2001 and 2003 half of all Maori women who gave birth were under the age of 26, with the 20 to 24 years age group having a fertility rate 2.7 rimes that of non-Maori women. Furthermore, data show that the median age of childbirth in 2003 was 26.2 years for Maori women and 30.1 years for non-Maori women (Ministry of Social Development 2008a, 2008b; Statistics New Zealand 2005, 2008). In addition, while non-Maori women over the past few decades have increasingly chosen to delay reproduction, a trend seen in other industrialised nations, there has been no increase in childbearing among Maori women over the age of 30 (Bean 2005, Ministry of Social Development 2008b).
In contrast to females, less is known about the demographic profile and parenthood experiences of Maori males who father children at an early age. International research suggests, however, that adolescent fathers often share a similar profile to that of adolescent mothers, with adolescent fathers also having lower levels of educational attainment, and exposure to socio-economic deprivation and family adversity in childhood (Coley and Chase-Lansdale 1998, Quinlivan and Condon 2005, Tan and Quinlivan 2006). Although a number of New Zealand studies have investigated the sexual and reproductive health of young Maori males, these generally report on early age of onset of sexual initiation (Fenwicke and Purdie 2000), contraceptive use (Clark et al. 2006) and sexual health status (Ministry of Health 2001).
The earlier age of first parenthood among Maori is likely to be one of the factors that contributes to the higher rate of socio-economic disadvantage experienced by Maori, leading to continuing ethnic disparities between Maori and other New Zealanders (Statistics New Zealand 2007b, Ministry of Social Development 2008b). This view is supported by international and New Zealand-derived research showing that early age of parenthood is related to lower educational achievement, higher rates of welfare receipt and lower income levels, leading to an elevated risk of experiencing poverty and material deprivation (Klepinger et al. 1995, Moore et al. 1995, Coley and Chase-Lansdale 1998, Hofferth et al. 2001, Singh et al. 2001, Hobcraft and Kiernan 2001, Robson and Berthoud 2006, Woodward et al. 2006, Boden et al. 2008). For these reasons, understanding early pregnancy and parenting by Maori is of significant theoretical and public policy importance. Broadly speaking, there are three theoretical perspectives that may explain the higher rates of early onset of pregnancy and parenthood by Maori.
The first perspective is based on the fact that, on a wide range of indices, Maori are subject to greater socio-economic disadvantage than non-Maori (Poata-Smith 1997, Chapple et al. 1997, Chapple 2000, Statistics New Zealand 2007, Ministry of Social Development 2008b). There is also considerable evidence to suggest that individuals from socially disadvantaged backgrounds become parents at an earlier age (Coley and Chase-Lansdale 1998, Woodward et al. 2001, Boden et al. 2008). Therefore, it may be that the earlier age of parenthood among Maori reflects the relative socio-economic positioning of Maori in New Zealand.
A second perspective regarding the differences between Maori and non-Maori in early pregnancy rates involves an ecological "at risk" model of familial adversity (Ramey and Landesman Ramey 1998, Repetti et al. 2002). Research indicates that, separate from economic disadvantage, Maori have greater exposure to negative childhood and related experience when compared to non-Maori (Fergusson 1998, Ministry of Social Development 2008a, 2008b, Fanslow et al. 2007). Exposure to family adversity in childhood has also been linked to early parenthood (Coley and Chase-Lansdale 1998, Quinlivan and Condon 2005, Tan and Quinlivan 2006).
A third perspective is based on the culture concept. Within New Zealand it is commonly held that Maori and non-Maori hold different normative value systems involving alternative conceptions of the character and role of gender relations and family (Metge 1990, Durie 1994). In recent years, Maori culture revitalisation has been actively promoted across a broad spectrum of fields, with emphasis being directed towards strengthening the cultural identity of individuals, families and tribal groupings (Greeenland 1991, Durie 1995, 1998, Webster 1998, Rata 2005, Marie et al. 2008). It could therefore be suggested that Maori and non-Maori hold different values regarding the optimum timing of human reproduction. Specifically, it is possible that some Maori may place a premium on early reproduction, whereby early pregnancy and parenthood has become institutionalised, via its normalisation, as a contemporary marker of strength of Maori cultural identity.
Against this background, the present study uses data from a longitudinal study of a birth cohort of New Zealand-born children in order to examine the associations between ethnic identity and early parenthood. Early parenthood and parenting is defined here as occurring before the age of 20 years. In the present paper, the term "ethnic identity" is used to denote Maori identity or non-Maori identity, while "cultural identity" denotes subgroups (sole Maori; Maori/other identity) within Maori ethnic identity. The specific aims of this study were to examine:
* differences in the rates at which Maori and non-Maori became parents before the age of 20 (this analysis included data for both females and males)
* the extent to which ethnic and differences in early parenthood could be explained by socio-economic factors, family factors and cultural identity.
The data were gathered during the course of the Christchurch Health and Development Study (CHDS), a birth cohort of 1,265 children (635 males, 630 females) born in the Christchurch (New Zealand) urban region in mid-1977, which has been studied at birth, 4 months, 1 year and annually to age 16 years, and again at ages 18, 21 and 25 years. Information from a variety of sources has been used, including: parental interviews, teacher reports, self-reports, psychometric assessments, and medical and other record data (Fergusson and Horwood 2001, Fergusson et al. 1989). The analyses reported here were based on the 992 study participants (78% of the original sample) for whom information was available concerning pregnancy and parenthood outcomes to age 20. Ali study information was collected on the basis of signed and informed consent from study participants.
Ethnic and Cultural Identity
At age 21 years respondents were asked about their ancestry, cultural identification, level of participation in Maori cultural domains and proficiency in the Maori language (Broughton et al. 2000). On the basis of this questioning, 11.1% of sample members self-identified as New Zealand Maori. A further break-down of this group showed 45.9% reporting sole Maori identity and 54.1% reporting Maori ethnic identity and identity with another ethnic group. For the purposes of the present analyses, those reporting sole Maori identity were classified as having a sole Maori cultural identity, while those reporting both Maori identity and another ethnic identity were classified as having Maori/other cultural identity. Ali other participants were classified as being non-Maori. The descriptors "sole Maori", "Maori/other cultural identity" and "non-Maori" were originally recommended by Pomare et al. (1995) in their analyses examining ethnic trends in public health epidemiology.
Comparisons of the sole Maori and Maori/other group showed consistent differences between the groups in terms of participation in eight different...