103 Changes in Vulvar Physiology and Skin Disorders with Age and Benefits of Feminine Wipes in Postmenopausal Women Miranda A. Farage . Kenneth W. Miller . William J. Ledger Introduction Vulvar skin changes over time. The most significant changes, which are hormonally mediated, are linked to the onset of puberty, the menstrual cycle, pregnancy, and menopause. Postmenopausal estrogen deficiency can lead to vulvar atrophy and irritation. This chapter reviews the morphology and physiology of the vulva over a woman’s lifetime, vulvar irritation associated with menopause, and studies on the benefits of feminine wet wipes in post- menopausal women. Effects of Aging on Vulvar Morphology, Physiology, and Susceptibility to Irritation The female lower urogenital tract is unique in that it is derived from all three embryonic germ cell layers: the ectoderm, the endoderm, and the mesoderm [1, 2]. Like the skin at other anatomical sites, the cutaneous epithelia of the mons pubis, labia, clitoris, and perineum originate from the embryonic ectoderm and exhibit a keratinized, stratified squamous structure with sweat glands, seba- ceous glands, and hair follicles [3, 4]. The degree of keratinization is greatest on the mons pubis and labia majora; it decreases over the clitoris and the outer surface and inner two thirds of the labia minora, the epidermis of the labia minora being thinner than that of the labia majora. From the inner one third of the surface of the labia minora through the vestibule, the vulvar epithelium is non-keratinized and is composed of mucosal tissue originating from the embryonic endoderm [2, 5]. The vagina originates from the embryonic mesoderm and bears a non-keratinized squamous epithelium that is responsive to estrogen cycling [1]. > Table 103.1 summarizes the changes in the mor- phology and physiology of the vulva over a woman’s lifetime. The most significant changes are hormonally mediated and linked to the onset of puberty, the menstru- al cycle, pregnancy, and menopause. From birth until about 4–6 weeks of age, the effects of residual maternal estrogens on the vulva are evidenced by swollen labia majora, well-developed labia minora, and a relatively large clitoris [3, 6]. During early childhood, the female genitalia receive little estrogen stimulation, resulting in flattened labia majora and thin labia minora and hymen [6]. Although vulvar hair follicles and seba- ceous glands are present at birth, these structures do not mature until the adrenal glands are activated at puberty. Prior to puberty, the labia minora has barely discernible vellus hair follicles; these disappear when the follicles of the labia majora and mons pubis terminally differentiate at puberty [7]. At puberty, adrenal and gonadal maturation induce further changes in vulvar skin. Follicular development causes estrogen production to rise: as estrogen stimula- tion increases, the vulvar epithelium thickens, the labial skin becomes rugose, and the clitoris becomes more prominent [4]. During the reproductive years, vulvar changes are linked to the menstrual cycle and pregnancy. The vulvar epidermis and dermis reach their fullest thickness during the reproductive years [3, 4](> Fig. 103.1). While vulvar epithelial thickness remains constant throughout the menstrual cycle, cytologic changes associated with sex hormone cycling have been observed [8]: Orthokeratosis predominates at the beginning of the menstrual cycle; parakeratosis increases at mid-cycle; then orthokeratosis rises once again by the end of the cycle. During pregnancy, an increase in total blood volume heightens the coloration of the vulva and the vagina. M. A. Farage, K. W. Miller, H. I. Maibach (eds.), Textbook of Aging Skin, DOI 10.1007/978-3-540-89656-2_103, # Springer-Verlag Berlin Heidelberg 2010