Using Twitter for prenatal health promotion: encouraging a multivitamin habit among college-aged females.

Half of the pregnancies in the United States are unplanned and the highest rate of these unplanned pregnancies occurs in young women aged 18-24y. Serious birth defects, such as those that affect the neural tube, occur early in pregnancy, most of the time before a woman knows she is pregnant. These neural tube defects can be reduced by 50-72% with an adequate daily intake of folic acid.