TY - JOUR
T1 - Are socioeconomic inequalities in the incidence of small-for-gestational-age birth narrowing? Findings from a population-based cohort in the South of England
AU - Wilding, Sam
AU - Ziauddeen, Nida
AU - Roderick, Paul
AU - Smith, Dianna
AU - Chase, Debbie
AU - Macklon, Nick
AU - McGrath, Nuala
AU - Hanson, Mark
AU - Alwan, Nisreen A.
N1 - © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.
PY - 2019/7/29
Y1 - 2019/7/29
N2 - OBJECTIVES: To investigate socioeconomic inequalities, using maternal educational attainment, maternal and partner employment status, and lone motherhood indicators, in the risk of small-for-gestational-age (SGA) births, their time trend, potential mediation by maternal smoking and body mass index, and effect modification by parity.DESIGN: Population-based birth cohort using routine antenatal healthcare data.SETTING: Babies born at University Hospital Southampton, UK, between 2004 and 2016.PARTICIPANTS: 65 909 singleton live births born to mothers aged ≥18 years between 24-week and 42-week gestation.MAIN OUTCOME MEASURES: SGA (birth weight <10th percentile for others born at the same number of completed weeks compared with 2013/2014 within England and Wales).RESULTS: Babies born to mothers educated up to secondary school level (adjusted OR (aOR) 1.32, 99% CI 1.19 to 1.47), who were unemployed (aOR 1.27, 99% CI 1.16 to 1.38) or with unemployed partners (aOR 1.27, 99% CI 1.13 to 1.43), were at greater risk of being SGA. There was no statistically significant change in the magnitude of this risk difference by these indicators over time between 2004 and 2016, as estimated by linear interactions with year of birth. Babies born to lone mothers were not at higher risk compared with partnered mothers after adjusting for maternal smoking (aOR 1.05, 99% CI 0.93 to 1.20). The inverse association between maternal educational attainment and SGA risk appeared greater in multiparous (aOR 1.40, 99% CI 1.10 to 1.77) compared with primiparous women (aOR 1.28, 99% CI 1.12 to 1.47), and the reverse was true for maternal and partner's unemployment where the association was stronger in primiparous women.CONCLUSIONS: Socioeconomic inequalities in SGA risk by educational attainment and employment status are not narrowing over time, with differences in association strength by parity. The greater SGA risk in lone mothers was potentially explained by maternal smoking. Preventive interventions should target socially disadvantaged women, including preconception and postpartum smoking cessation to reduce SGA risk.
AB - OBJECTIVES: To investigate socioeconomic inequalities, using maternal educational attainment, maternal and partner employment status, and lone motherhood indicators, in the risk of small-for-gestational-age (SGA) births, their time trend, potential mediation by maternal smoking and body mass index, and effect modification by parity.DESIGN: Population-based birth cohort using routine antenatal healthcare data.SETTING: Babies born at University Hospital Southampton, UK, between 2004 and 2016.PARTICIPANTS: 65 909 singleton live births born to mothers aged ≥18 years between 24-week and 42-week gestation.MAIN OUTCOME MEASURES: SGA (birth weight <10th percentile for others born at the same number of completed weeks compared with 2013/2014 within England and Wales).RESULTS: Babies born to mothers educated up to secondary school level (adjusted OR (aOR) 1.32, 99% CI 1.19 to 1.47), who were unemployed (aOR 1.27, 99% CI 1.16 to 1.38) or with unemployed partners (aOR 1.27, 99% CI 1.13 to 1.43), were at greater risk of being SGA. There was no statistically significant change in the magnitude of this risk difference by these indicators over time between 2004 and 2016, as estimated by linear interactions with year of birth. Babies born to lone mothers were not at higher risk compared with partnered mothers after adjusting for maternal smoking (aOR 1.05, 99% CI 0.93 to 1.20). The inverse association between maternal educational attainment and SGA risk appeared greater in multiparous (aOR 1.40, 99% CI 1.10 to 1.77) compared with primiparous women (aOR 1.28, 99% CI 1.12 to 1.47), and the reverse was true for maternal and partner's unemployment where the association was stronger in primiparous women.CONCLUSIONS: Socioeconomic inequalities in SGA risk by educational attainment and employment status are not narrowing over time, with differences in association strength by parity. The greater SGA risk in lone mothers was potentially explained by maternal smoking. Preventive interventions should target socially disadvantaged women, including preconception and postpartum smoking cessation to reduce SGA risk.
KW - public health
KW - small for gestational age
KW - social medicine
KW - socioeconomic inequalities
KW - Follow-Up Studies
KW - Humans
KW - Risk Factors
KW - England/epidemiology
KW - Male
KW - Population Surveillance/methods
KW - Socioeconomic Factors
KW - Incidence
KW - Pregnancy
KW - Young Adult
KW - Adolescent
KW - Premature Birth/epidemiology
KW - Adult
KW - Female
KW - Infant, Small for Gestational Age
KW - Retrospective Studies
KW - Wales/epidemiology
KW - Infant, Newborn
UR - http://www.scopus.com/inward/record.url?scp=85070811790&partnerID=8YFLogxK
U2 - 10.1136/bmjopen-2018-026998
DO - 10.1136/bmjopen-2018-026998
M3 - Article
C2 - 31362961
AN - SCOPUS:85070811790
SN - 2044-6055
VL - 9
SP - e026998
JO - BMJ Open
JF - BMJ Open
IS - 7
M1 - e026998
ER -