Menthol-flavored e-cigarettes may pose significant risks to fetal development, potentially causing birth defects, according to a new study. Researchers at the University of California, Riverside, found that menthol activates stress-related channels in human embryonic stem cells, inhibiting growth and increasing cell death during critical development stages. Menthol-flavored e-cigarettes may pose significant risks to fetal development, potentially causing birth defects, according to a new study. Researchers at the University of California, Riverside, found that menthol activates stress-related channels in human embryonic stem cells, inhibiting growth and increasing cell death during critical development stages. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle