In a cohort study of 2,529 women, researchers sought to determine the effects of caffeinated-beverage intake on gestational diabetes (GDM), preeclampsia, and gestational hypertension (GH). Findings revealed low to moderate caffeine intake (less than 200 mg per day) early in the second trimester was associated with a lower risk of GDM, lower glucose levels at GDM screening, and improved cardiometabolic profile compared with no consumption.
The authors said: “Caffeine in itself has been associated with improved energy balance and decreased fat mass, which could play a role in the biological mechanism for the observed associations.”
The study findings “address critical data gaps on the health implications of caffeine consumption in pregnancy for maternal health”, although the researchers advise against initiating caffeine consumption for the purpose of lowering GDM risk or improving glucose metabolism.
Implications of caffeine
The American College of Obstetricians and Gynaecologists (ACOG) recommends caffeine consumption below the 200 mg/d during pregnancy due to its association with smaller neonatal anthropometric measurements.
According to the research team, very few women consume high levels of caffeine and so “it is difficult to make inferences about risk across the spectrum of potential intake”. But significant observational data from the current study demonstrates a number of positive associations.
Researchers noted a 47% reduction in risk of gestational diabetes with caffeinated beverage intake of 100 mg/d in the second trimester (16-22) compared with no intake. It was also linked to lower glucose, C-reactive proteins (CRPs) and C-peptide concentrations, and more favourable lipid profiles.
There was no significant association observed with first trimester (10-13 weeks) self-reported intake, although caffeinated beverage intake of 1 mg/d to 100 mg/d and 101 mg/d to 200 mg/d was not related to GDM risk. Total plasma caffeine and paraxanthine were inversely associated with glucose at this stage.
Neither low or moderate caffeinated beverage intake, or plasma caffeine and paraxanthine were associated with risk of gestational hypertension, preeclampsia or blood pressure levels across pregnancy.
The authors added: “Null findings between caffeine and preeclampsia are somewhat surprising given that better lipid profiles were observed among women who drank caffeinated beverages in the second trimester and dyslipidemia has been associated with preeclampsia risk.”
Study protocol
The research, commissioned by the National Institute of Child Health and Human Development (NICHD), focused on second trimester (16-22 weeks) measures and continuous measures of glucose and cardiometabolic biomarkers.
A total of 2.583 participants were enrolled between gestational weeks 8 to 13 at 12 US clinical centres and eligibility limited to women who did not smoke, abuse alcohol, take illicit drugs, who conceived without fertility drugs or IVF, had no previous pregnancy complications, nor suffer from major chronic diseases.
Women reported their weekly intake of caffeinated coffee, caffeinated tea, and other drinks with caffeine (soda and energy drinks) at enrolment and at regular intervals throughout the trial.
First trimester concentrations of plasma caffeine and paraxanthine were collected and matched with clinical diagnoses of gestational diabetes, gestational hypertension, and preeclampsia.
Research background
Prior studies on caffeine or coffee intake in pregnancy and gestational hypertension and preeclampsia risk have been inconsistent. One small study reported no association between second trimester paraxanthine and preecalmpsia.
Another study found that mean intake across pregnancy of self-reported caffeinated coffee and tea was not associated with gestational hypertension or preeclampsia risk, although there was an inverse association between intakes of 180 mg/d to 351 mg/d and preeclampsia, which was reported as unexpected and needing replication. This study also observed a positive association between third trimester caffeine intake of 360 mg/d to 531 mg/d and systolic blood pressure.
Conclusion
The authors explain study results are based on observational data so confounding factors cannot be completely ruled out even though major known confounders were adjusted for in this study.
Further research is therefore required to better understand the underlying molecular mechanisms for these findings and identify relevant components.
Despite study limitations the team adds, “the findings should be reassuring for pregnant women with moderate caffeine intake” although “translation into public health recommendations should be considered in the context of published data on offspring outcomes.”
Source: JAMA Network
Stefanie N. Hinkle, PhD; Jessica L. Gleason, PhD, MPH; Samrawit F. Yisahak, PhD; Sifang Kathy Zhao, PhD; Sunni L. Mumford, PhD, MSc; Rajeshwari Sundaram, PhD, MS; Jagteshwar Grewal, PhD; Katherine L. Grantz, MD, MS; Cuilin Zhang, MD, PhD, MPH
“Assessment of Caffeine Consumption and Maternal Cardiometabolic Pregnancy Complications”
doi:10.1001/jamanetworkopen.2021.33401