An easy access to products containing caffeine makes it widely consumed to excess by the general population, including pregnant women. Beverages containing caffeine are consumed at different temperatures (iced, hot, room temperature). Caffeine easily passes through biological membranes, including the blood-brain barrier, the placental barrier, and can also enter the amniotic fluid, breast milk and semen. The aim of this study was to evaluate the relationship between caffeine’s developmental toxicity, and the solution’s temperature (both low and high) administered to pregnant female rats. Fertilized females were randomly divided into two main groups: an experimental (E) and a control group (C). The experimental groups received caffeine (30mg/day) in 10 (E₁), 25 (E₂) and 45^oC (E₃). The females in the control group were given water at the same temperature (C₁, C₂ and C₃). On the day 21 of pregnancy, the pregnant females were killed by decapitation, using a specially prepared laboratory guillotine, after which the mothers’ internal organs were weighed. Additionally, the offspring were examined using standard teratological methods. The study found that caffeine administered to pregnant females at a dose of 30mg/day and at the temperatures of 10°C, 25°C or 45°C did not produce any teratogenic effects. The only sign of its adverse effect was the appearance of developmental abnormalities in the form of haematomas and saturated bleeding in the internal organs. These changes most frequently occurred in foetuses of females which received caffeine at 10°C or 45°C.