Immune and Hormone Response to Influenza Vaccine

The purpose of this pilot research project is to look at the effect of the inactivated influenza vaccine (seasonal flu shot) on early signs of immune or germ-fighting response known as cytokines or signal molecules. The investigators also want to see if the timing of vaccine administration has any effect on women's reproductive hormones. The investigators hypothesis is that influenza vaccine given right before ovulation may change the hormone levels usually seen after ovulation. Thi