Risk factors for first trimester miscarriage—results from a UK-population-based case–control study
Article first published online: 5 DEC 2006
RCOG 2006 BJOG An International Journal of Obstetrics and Gynaecology
BJOG: An International Journal of Obstetrics & Gynaecology
Volume 114, Issue 2, pages 170–186, February 2007
How to Cite
Maconochie, N., Doyle, P., Prior, S. and Simmons, R. (2007), Risk factors for first trimester miscarriage—results from a UK-population-based case–control study. BJOG: An International Journal of Obstetrics & Gynaecology, 114: 170–186. doi: 10.1111/j.1471-0528.2006.01193.x
- Issue published online: 9 JAN 2007
- Article first published online: 5 DEC 2006
- Accepted 19 October 2006. Published OnlineEarly 4 December 2006.
- paternal factors;
- pregnancy history;
- UK population
Objective The aim of this study was to examine the association between biological, behavioural and lifestyle risk factors and risk of miscarriage.
Design Population-based case–control study.
Setting Case–control study nested within a population-based, two-stage postal survey of reproductive histories of women randomly sampled from the UK electoral register.
Population Six hundred and three women aged 18–55 years whose most recent pregnancy had ended in first trimester miscarriage (<13 weeks of gestation; cases) and 6116 women aged 18–55 years whose most recent pregnancy had progressed beyond 12 weeks (controls).
Methods Women were questioned about socio-demographic, behavioural and other factors in their most recent pregnancy.
Main outcome measure First trimester miscarriage.
Results After adjustment for confounding, the following were independently associated with increased risk: high maternal age; previous miscarriage, termination and infertility; assisted conception; low pre-pregnancy body mass index; regular or high alcohol consumption; feeling stressed (including trend with number of stressful or traumatic events); high paternal age and changing partner. Previous live birth, nausea, vitamin supplementation and eating fresh fruits and vegetables daily were associated with reduced risk, as were feeling well enough to fly or to have sex. After adjustment for nausea, we did not confirm an association with caffeine consumption, smoking or moderate or occasional alcohol consumption; nor did we find an association with educational level, socio-economic circumstances or working during pregnancy.
Conclusions The results confirm that advice to encourage a healthy diet, reduce stress and promote emotional wellbeing might help women in early pregnancy (or planning a pregnancy) reduce their risk of miscarriage. Findings of increased risk associated with previous termination, stress, change of partner and low pre-pregnancy weight are noteworthy, and we recommend further work to confirm these findings in other study populations.