pathways to parenthood: exploring the influence of context as a predictor of early parenthood phd...
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Pathways to Parenthood: Exploring the influence of
Context as a Predictor of Early Parenthood
PhD Student: Dylan KnealeSupervisors: Professor Heather Joshi and Dr Jane Elliott
Background
• Contemporary early parenthood is set against a movement towards an older overall age at first birth.
• Rising age has lead to increasing social polarisation in age at first parenthood.
• Investigations have concentrated on early parenthood as a social problem and not as a demographic event.
• Demographic theories explaining variations in fertility patterns have therefore been neglected
• Diffusion theory attributes causality to contextual factors as predictors of fertility patterns.
Mission Statement I
• Given rising age at first birth, define what constitutes early parenthood.
• Use a wide definition of context to examine the effects of: - Interactions with mass media - Neighbourhood- Partnership market/characteristics
- School characteristics
- Peer effects
- Parental input• Top down approach to analysis of social networks
used
Mission Statement II
• Evaluate the magnitude of contextual predictors based on measurement point (childhood, teenage years and early adulthood)
• Policy implications include guidance for potential intervention strategies aimed at reducing levels of early fertility.
• Further policy implications from cross cohort analysis in terms of predicting future trends of early fertility
• Methodological contribution made in the evaluation of techniques used to analyse fertility patterns.
Utilise strengths of the birth cohort studies to examine factors affecting fertility.
• National Child Development Study (NCDS) – Originally included all live births in G.B from one month in 1958.
• British Cohort Study (BCS70) – Originally included all live births in U.K from one month in 1970.
• In both studies, the addition of immigrants has been offset by attrition:
Data
Cohort Original Sample
No. ever involved
Previous (2004) Sample
NCDS 17,634 18,558 9,534
BCS70 16,572 17,287 9,665
1958 NCDS Birth
1965 NCDS
(Age 7) 1969
NCDS (Age 11)
1970 BCS70 Birth
1974 NCDS
(Age 16)
1975 BCS70 (Age 5)
1981 NCDS
(Age 23)
1980 BCS70
(Age 10)
1986 BCS70
(Age 16)
1991 NCDS
(Age 33)
1996 BCS70
(Age 26)
2000 NCDS
(Age 42)
2000 BCS70
(Age 30)
2004 BCS70
(Age 34)
2004 NCDS
(Age 46)
Data Collection NCDS
Data Collection BCS70
•What is early parenthood?
•Early parenthood synonymous with teenage parenthood in media
•Is this meaningful distinction or just convention?
•Age specific fertility rate for teenagers decreased from 30 births per 1000 women in 1985 to 26 births per 1000 in 2005 (ONS)
•Is focus reactive to media and political constructions or real differences?
•What is early parenthood?
Number of Articles by Definition of Motherhood with UK Birth Trends
0
5
10
15
20
25
30
35
40
45
50
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006Year of Publication
Num
ber
of
Art
icle
s
24
25
26
27
28
29
30
31
32
Age
Speci
fic
Fert
ilit
y
Rate
- B
irth
s per
1000
wom
en
Teenage Motherhood
Early Motherhood
Age Specific FertilityRate - Teenagers
How should early parenthood be defined?
i
ii
n
dntS )(
•Using absolute cut off points, survival analysis and piecewise regression to derive definitions of early parenthood:
•The literature supports the idea that the effects of the timing of parenthood are felt up to a certain point, changing after this. Piecewise regression methods are used to test this proposition.
)]_*__([ 12110 dummybreakvaluebreakstructuralxxy
How should early parenthood be defined – example output…..
Household Income Age 46 Coef. (£) P>|t|[95% Conf.
Interval]
age1 1201.2 0.000 884.2 1518.2
age2 -1487.7 0.001 -2343.5 -632.0
_cons 15802.2 0.000 7515.0 24089.5
•In the above output, a spline has been identified at age 32. Up to this age, delaying fatherhood corresponds to an increase in household income of value age1 (However, other factors do mitigate the relationship)
• Age2 corresponds to the value of the difference between slopes up to 32 years and ages afterwards – significantly different
How could early fatherhood be defined?
Birth
14 years 5 months, first
NCDS father
15 years 2 months, first
BCS70 father
Teenage
23 years 11 months, first
12.5% of BCS70
cohort are fathers
21 years 2 months, first
12.5% of NCDS
cohort are fathers
24 years 11 months, first
25% of NCDS
cohort are fathers
27 years, first 25% of
BCS70 cohort are
fathers
27 years spline
identified from NCDS
cm’s mother’s
age at first birth
28 years spline
identified from NCDS test scores
32 years spline
identified from NCDS
income
Conclusion: Teenage definition is a poor definition of early fatherhood. Given the data, a proportional definition is satisfactory
How could early motherhood be defined?
Birth
13 years 2 months, first
NCDS mother
15 years 2 months, first
BCS70 mother
Teenage
20 years 8 months, first
12.5% of BCS70
cohort are mothers
19 years 11 months, first
12.5% of NCDS
cohort are mothers
22 years 2 months, first
25% of NCDS
cohort are mothers
23 years 11 months, first
25% of BCS70
cohort are mothers
27 years spline
identified from NCDS
cm’s mother’s
age at first birth
28 years spline
identified from NCDS test scores
33 years spline
identified from NCDS
income
Conclusion: Teenage definition is a poor definition of early motherhood. Given the data, a proportional definition is satisfactory
How many early parents feature in NCDS and BCS70? – the definitions to be used in the remainder of the research….
Gender DefinitionNCDS BCS70
No. Age No. Age
♂Teenage 278 <20 188 <20
First 12.5%* 892 21y 2m 735 23y 11m
First 25%* 1684 24y 11m 1466 27y
♀
Teenage** 903* <20 615 <20
First 12.5%* 885 19y 11m 761 20y 8m
First 25%* 1763 22y 2m 1519 23y 11m
Parents at 46Childless at 46*
(%)Parents at 34
Childless at 34* (%)
♂ Timing 4646 21% 2997 44%
♀ Timing 5304 16% 4060 30%
*Based upon KM estimates; **because this definition does not vary significantly from 12.5%, it will not be used extensively in further research
Research Findings I• Diffusion theory not supported by a large body of
empirical evidence and early parenthood in the literature is synonymous with teenage parenthood.
• Data from the NCDS and BCS70 reveals that teenage parents are a dwindling population.
• Teenage parents share characteristics with parents in their early to mid twenties - proportional definition of early parenthood should therefore be used.
• Widely used Cox’s Proportional Hazards Models provide an insufficient fit for modelling entry into parenthood data - Lognormal AFT models favoured
• Ability in maths is more predictive than ability in reading for early parenthood - this may extend to other lifecourse events.
Research Findings II• More variables reflective of socioeconomic
characteristics predict early motherhood than early fatherhood.
• Variables reflective of personality superseded in this research by attitudinal variables. Age at which young people think it’s best to get married is a significant predictor of fertility for males and females.
• Parental Interest in education found to be an important predictor of early fertility - less interested parents correspond to earlier first parenthood. However, over interest found to increase onset to early parenthood. (not submitted but fed into models)
• Age difference between parents at first birth is significant.
Research Findings III• Early childhood (age 7 years) factors play a greater role
in predicting early fatherhood. Conditions experienced during middle childhood and teenage years (age 11 and 16 years) play a greater role in predicting early motherhood.
• Women in rural areas more likely to experience early motherhood, but not teenage motherhood
• Neighbourhood a stronger predictor for fatherhood than motherhood. May demonstrate greater heterogeneity among early fathers and increased importance of partner’s characteristics.
• Age at first motherhood an increasing marker of social polarisation. 31% of graduate women born in 1970 are expected to remain childless; 24% of graduate women born in 1958.Trend reversed for women with no qualifications.
Future Directions I• Isolate true effect of neighbourhood using multilevel
modelling applied to both cohorts.• Continue to derive and analyse the effects of other
background variables. Includes further analyses of attitudinal variables
• Examine school based characteristics as a measure of social networks.
• Analyse the effects of mass media consumption as a predictor of early parenthood.
• Establish to what extent fertility patterns of cohort members are influenced by interaction with their peers.
Future Directions II• Continue investigation into parental input including
cohort members’ perceptions of parental relationships.
• Examine partnership characteristics. Measure social differentials in the characteristics of partners - examine in particular if a greater homogeneity exists among the partners of early fathers than amongst early fathers themselves.
• Analyse inter cohort differences in the direction and magnitude of contextual predictors.
• Measure the extent of increasing social polarisation in the age at first birth; make predictions for future trends