Associations between consumption of coffee and caffeinated soft drinks and late stillbirth-Findings from the Midland and North of England stillbirth case-control study

Mothers working to prevent early stillbirth study (MiNESS 20-28): a case-control study protocol

INTRODUCTION

In the UK, 1600 babies die every year before, during or immediately after birth at 20-28 weeks' gestation. This bereavement has a similar impact on parental physical and psychological well-being to late stillbirth (>28 weeks' gestation). Improved understanding of potentially modifiable risk factors for late stillbirth (including supine going-to-sleep position) has influenced international clinical practice. Information is now urgently required to similarly inform clinical practice and aid decision-making by expectant mothers/parents, addressing inequalities in pregnancy loss between 20 and 28 weeks.

METHODS AND ANALYSIS

This study focuses on what portion of risk of pregnancy loss 20-28 weeks' gestation is associated with exposures amenable to public health campaigns/antenatal care adaptation. A case-control study of non-anomalous singleton baby loss (via miscarriage, stillbirth or early neonatal death) 20+0 to 27+6 (n=316) and randomly selected control pregnancies (2:1 ratio; n=632) at group-matched gestations will be conducted. Data is collected via participant recall (researcher-administered questionnaire) and extraction from contemporaneous medical records. Unadjusted/confounder-adjusted ORs will be calculated. Exposures associated with early stillbirth at OR≥1.5 will be detectable (p<0.05, β>0.80) assuming exposure prevalence of 30%-60%.

ETHICS AND DISSEMINATION

NHS research ethical approval has been obtained from the London-Seasonal research ethics committee (23/LO/0622). The results will be presented at international conferences and published in peer-reviewed open-access journals. Information from this study will enable development of antenatal care and education for healthcare professionals and pregnant people to reduce risk of early stillbirth.

TRIAL REGISTRATION NUMBER

NCT06005272.

Assessment of caffeine intake in groups of pregnant and breastfeeding women: A cross-sectional analysis

BACKGROUND & AIMS

Caffeine is commonly consumed by pregnant and breastfeeding women. The maximum safe dose of caffeine in their diet is 200 mg per day, according to the European Food Safety Authority. The purpose of this study was to assess the consumption of caffeinated products by pregnant and breastfeeding women, as well as to estimate their caffeine intake.

METHODS

The number of subjects who qualified for the study was 1112 women, of whom 401 were pregnant and 711 were breastfeeding. The research was conducted with the use of a questionnaire, which included information about food frequency and history of consumption of caffeinated products during the past 3 days.

RESULTS

The median (interquartile range) daily caffeine intake among pregnant women was 114.5 (57.6-202.8) mg, and the level of caffeine intake increased with the duration of pregnancy (p < 0.001). For breastfeeding women it was 193.7 (100.5-324.8) mg/d. The majority of participants (58.9%) were not able to correctly identify the safe amount of caffeine in their diets. It was observed that the intake of 73.8% of pregnant women and 51.9% of breastfeeding women fit within the safe range (0-200 mg/d). The main sources of caffeine were ground coffee, black tea, and instant coffee. For 63,6% of women knowledge about nutrition and supplementation came most often from blogs and social media run by medical professionals. Pleasure was the main reason for drinking coffee and tea.

CONCLUSION

Most pregnant women did not exceed the recommended maximum daily dose of caffeine, while breastfeeding women often did.

Maternal dietary caffeine consumption and risk of birth defects in the National Birth Defects Prevention Study, 1997-2011

BACKGROUND

Caffeine consumption is common during pregnancy, but published associations with birth defects are mixed. We updated estimates of associations between prepregnancy caffeine consumption and 48 specific birth defects from the National Birth Defects Prevention Study (NBDPS) for deliveries from 1997 to 2011.

METHODS

NBDPS was a large population-based case-control study conducted in 10 U.S. states. We categorized self-reported total dietary caffeine consumption (mg/day) from coffee, tea, soda, and chocolate as: <10, 10 to <100, 100 to <200, 200 to <300, and ≥ 300. We used logistic regression to estimate adjusted odds ratios (aORs [95% confidence intervals]). Analyses for defects with ≥5 exposed case children were adjusted for maternal race/ethnicity, age at delivery, body mass index, early pregnancy cigarette smoking and alcohol use, and study site.

RESULTS

Our analysis included 30,285 case and 11,502 control children, with mothers of 52% and 54%, respectively, reporting consuming <100 mg caffeine, and 11% of mothers of both cases and controls reported consuming ≥300 mg per day. Low (10 to <100 mg/day) levels of prepregnancy caffeine consumption were associated with statistically significant increases in aORs (1.2-1.7) for 10 defects. Associations with high (≥300 mg/day) levels of caffeine were generally weaker, except for craniosynostosis and aortic stenosis (aORs = 1.3 [1.1-1.6], 1.6 [1.1-2.3]).

CONCLUSIONS

Given the large number of estimates generated, some of the statistically significant results may be due to chance and thus the weakly increased aORs should be interpreted cautiously. This study supports previous observations suggesting lack of evidence for meaningful associations between caffeine consumption and the studied birth defects.

Relationship between maternal caffeine and coffee intake and pregnancy loss: A grading of recommendations assessment, development, and evaluation-assessed, dose-response meta-analysis of observational studies

Background

Numerous studies report an association between coffee or caffeine consumption and pregnancy loss; however, the nature and strength of this relationship have not been clearly established. Based on recent studies, our meta-analysis aimed to test whether a dose-response relationship between coffee or caffeine consumption and pregnancy loss exists.

Methods

We searched for articles in PubMed, Web of Science, and Scopus published until May 2022. Two independent reviewers extracted data and rated the quality of the evidence using the GRADE approach. We applied a random-effects, one-stage dose-response meta-analysis.

Results

A total of 34 articles (18 cohort studies and 16 case-control studies) were included in this review. Results showed a significantly higher risk of pregnancy loss for coffee consumption before (Pooled ES: 1.21; 95% CI: 1.01-1.43) and during pregnancy (Pooled ES: 1.26; 95% CI: 1.04-1.57), and for coffee consumption during pregnancy in case-control studies (Pooled ES: 1.20; 95% CI: 1.19-6.41). Findings from this meta-analysis demonstrated that caffeine intake during pregnancy was associated with a significantly higher risk of pregnancy loss in cohort (Pooled ES: 1.58; 95% CI: 1.23-2.01) and case-control studies (Pooled ES: 2.39; 95% CI: 1.69-3.37, P < 0.001), respectively. A dose-response analysis suggested that an increase of a cup of coffee per day during pregnancy was associated with 3% increased risk of pregnancy loss; 100 mg of caffeine per day during pregnancy was also associated with 14 and 26% increased risk of pregnancy loss in cohort and case-control studies, respectively. A non-linear dose-response association was observed between coffee intake and the risk of pregnancy loss.

Conclusion

This study confirms that coffee or caffeine consumption raises the risk of pregnancy loss. Researchers are encouraged to conduct more studies to explore the underlying mechanisms and active compounds in coffee and caffeine.

Systematic Review Registration

[www.crd.york.ac.uk/prospero/], identifier [CRD42021267731].

An exploration of migrant women's perceptions of public health messages to reduce stillbirth in the UK: a qualitative study

BACKGROUND

Stillbirth is a global public health priority. Within the United Kingdom, perinatal mortality disproportionately impacts Black, Asian and minority ethnic women, and in particular migrant women. Although the explanation for this remains unclear, it is thought to be multidimensional. Improving perinatal mortality is reliant upon raising awareness of stillbirth and its associated risk factors, as well as improving maternity services. The aim of this study was to explore migrant women's awareness of health messages to reduce stillbirth risk, and how key public health messages can be made more accessible.

METHOD

Two semi-structured focus groups and 13 one to one interviews were completed with a purposive sample of 30 migrant women from 18 countries and across 4 NHS Trusts.

RESULTS

Participants provided an account of their general awareness of stillbirth and recollection of the advice they had been given to reduce the risk of stillbirth both before and during pregnancy. They also suggested approaches to how key messages might be more effectively communicated to migrant women.

CONCLUSIONS

Our study highlights the complexity of discussing stillbirth during pregnancy. The women in this study were found to receive a wide range of advice from family and friends as well as health professionals about how to keep their baby safe in pregnancy, they recommended the development of a range of resources to provide clear and consistent messages. Health professionals, in particular midwives who have developed a trusting relationship with the women will be key to ensuring that public health messages relating to stillbirth reduction are accessible to culturally and linguistically diverse communities.