Summary: Male and female sexuality and reproductive functions are complex systems with cortical, limbic system, hypothalamic, pituitary, and end organ interactions. Sexual steroids are produced in the sexual glands, the adrenals, and the brain. They undergo interconversion in the brain, bind to different brain areas, and have multiple effects behaviorally and neuro-physiologically. Progesterone, estrogen and testosterone have neuroendocrine effects that alter epileptogenicity. Seizure frequency may change throughout the life cycle as a result of hormonal status. Changes in central control, peripheral hormone levels, and/or medication effects may all contribute to decreased libido, potency, and fertility. Antiepileptic drugs (AEDs) interact with hormone-binding metabolism, resulting in altered human reproductive function. AEDs alter contraceptive hormone treatments. Information on the effects of new AEDs is being gathered by the National Pregnancy Registry. Catamenial epilepsy and some sexual dysfunction in men may be treatable.