Modest maternal caffeine exposure affects developing embryonic cardiovascular function and growth.
Level 5 - mechanism / opinion, no new human data
Animal research (CD-1 mouse model)
PubMed 18359892 · doi:10.1152/ajpheart.91469.2007
What was done
Pregnant CD-1 mice received daily subcutaneous caffeine (10 mg/kg/day) from embryonic day (ED) 9.5 to 18.5 of gestation. Maternal and embryonic cardiovascular function were measured via high-resolution echocardiography at baseline and at peak maternal serum caffeine concentrations on ED 9.5, 11.5, 13.5, and 18.5. The investigators evaluated fetal crown-rump length, body weight, embryo resorption, effects of an adenosine A2A receptor inhibitor, and tissue-specific A2A receptor gene expression.
What was found
Maternal caffeine did not alter maternal body weight gain, maternal cardiovascular function, or embryo resorption. Caffeine-exposed embryos showed reduced crown-rump length and body weight by ED 18.5 (P < 0.05). At peak maternal caffeine levels on ED 11.5, embryonic carotid artery, dorsal aorta, and umbilical artery flows transiently decreased from baseline (P < 0.05). By ED 13.5, carotid flow remained altered, and by ED 18.5, baseline embryonic carotid flow increased while descending aortic flow decreased versus controls. Adenosine A2A receptor inhibition replicated these hemodynamic alterations, and A2A receptor gene expression decreased in ED 11.5 embryos and ED 18.5 uteri. Specific numeric values for weights and blood flow rates were not reported in the abstract.
Why it matters
This study provides evidence of a direct embryonic hemodynamic and adenosine A2A receptor-mediated mechanism underlying caffeine-related fetal growth restriction, occurring independently of maternal systemic cardiovascular changes.
Limits
This is an animal study in mice, which may not directly translate to human pregnancy dynamics or dosing. The abstract does not report the sample size (number of dams or embryos) or absolute hemodynamic and growth values, and postnatal persistence of these cardiovascular changes was not evaluated.
Cited by
- supports Animal studies show that maternal caffeine consumption during pregnancy causes smaller offspring, altered cardiac development, and delayed fetal brain growth.