Structure and innervation of the labia minora: more than minor skin folds

Ginger VAT, Cold C J, Yang C C (2011) 4: 180-3

This was a retrospective histological follow up study in eight postmenopausal cadaveric specimens, looking at the features of the labial minora in relation to the female sexual response. The background was that the labial minora are specialised non-erectile vascular structures that show an increase in blood flow and volume in women during audio-visual sexual arousal.

The result showed highly variable labia minora in gross appearance. The microscopic examination showed thin keratinised genital transitional skin with variable number of sebaceous glands. It also contains abundance of elastin and neural structures. There does not seem to be a difference in the distribution of neural elements between the lateral and medial aspects.

It was therefore concluded, that though they were able to identify vascular structures within the labia minora and corroborate the structures with increased blood flow during sexual arousal, the purpose of this is still inconclusive. This is because it is known from scientific textbooks that in contrast to the labia majora, the number of vascular structures in the labia is significantly larger, much more than would be expected to maintain baseline vascular sufficiency for a small skin fold.

Interestingly, the authors pointed out that these days, genital reconstructive surgeries are carried out. This being for aesthetic or functional reasons with a trend towards cosmetic labioplasty. It is advised that the structures and functions of the labial minora be taken into account when counseling women regarding such operations, with the potential for altered sensitivity and interference with the arousal mechanism.

The limitations of this study are that this information is already in textbooks of anatomy and physiology, and the use of postmenopausal women, likely to have undergone some elements of hormonal dependent degenerative changes.