Systematic review and meta-analysis of female lifestyle factors and risk of recurrent pregnancy loss

Ka Ying Bonnie Ng,Nick Macklon,Sesh K Sunkara,George Cherian,Sarah Bailey,Alexandra J Kermack,Ying Cheong

doi:10.1038/s41598-021-86445-2

Abstract

It is known that lifestyle factors affect sporadic miscarriage, but the extent of this on RPL (recurrent pregnancy loss) is less well known. A systematic review and meta-analysis was performed to assess the associations between lifestyle factors and RPL. Studies that analysed RPL in the context of BMI, smoking, alcohol and caffeine intake were included. The primary and secondary outcomes were odds of having RPL in the general population and odds of further miscarriage, respectively. Underweight and women with BMI > 25 are at higher odds of RPL in the general population (OR 1.2, 95% CI 1.12–1.28 and OR 1.21, 95% CI 1.06–1.38, respectively). In women with RPL, having BMI > 30 and BMI > 25 has increased odds of further miscarriages (OR 1.77, 95% CI 1.25–2.50 and OR 1.35, 95% CI 1.07–1.72, respectively). The quality of the evidence for our findings was low or very low. Being underweight and BMI > 25 contributes significantly to increased risk of RPL (general population). BMI > 25 or BMI > 30 increases the risk of further miscarriages (RPL population). Larger studies addressing the effects of alcohol, cigarette smoking and caffeine on the risk of RPL with optimisation of BMI in this cohort of women are now needed.

Highlights

IntroductionIt is known that lifestyle factors affect sporadic miscarriage, but the extent of this on Recurrent pregnancy loss (RPL) (recurrent pregnancy loss) is less well known
It is known that lifestyle factors affect sporadic miscarriage, but the extent of this on Recurrent pregnancy loss (RPL) is less well known
The search term used for miscarriage history included ‘early pregnancy loss’, ‘miscarriage’, ‘recurrent pregnancy loss’, ‘recurrent miscarriage’ and ‘spontaneous abortion’

Summary

Introduction

It is known that lifestyle factors affect sporadic miscarriage, but the extent of this on RPL (recurrent pregnancy loss) is less well known. Being underweight and BMI > 25 contributes significantly to increased risk of RPL (general population). The literature studying the effects of various lifestyle factors on RPL has not been comprehensively reviewed and current recommendations[3] are based on evidence from studies on a population who have had sporadic miscarriages. These findings may not be extrapolated to those with RPL. Very lowa,b Lowa Lowa embryonic karyotype significantly reduces[8] This suggests that the impact of lifestyle may be more significant on the RPL population compared to those with an isolated early miscarriage

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Results

Discussion

Conclusion