I'm a first time mom and just 3 weeks pregnant (5 weeks menstral age). I've come down with the flu and think I have a fever. I'm terrified right now b/c everything I've read says fever can cause miscarriage and neural tube defects especially if you have it during days 20 to 28 when the neural tube is forming and closing. I'm 21 days and at the exact gestation that is most sensitive to the effects of fever. Does anyone know anything that can help alleve my fears. I've sent my husband out to get a thermometer and Tylenol.