Vestibulo-vaginal stricture is a collective term used in this text for any defect which leads to a narrowing or any form of obstruction of the vagina. The vestibule is the first part of the canal that leads into the vaginal canal. Vestibular stricture or stenosis is a narrowing in the first few centimetres of the vagina which restricts the introduction of the penis. These strictures can easily be palpated with the index finger although strictures deeper in the vagina can only be diagnosed using endoscopy. Other forms of obstructions include dorsoventral bands (band stretching from top to bottom in vagina), vaginal septae (bands of tissue dividing the vagina into two parts) and segmental aplasia (a missing portion of the vagina). Considering that some of these abnormalities appear more in certain breeds than in others, heritability cannot be excluded. Irrespective of the cause of narrowing, the bitch will object to penetration by the male due to pain or space constraints. Even if the problem is surgically corrected, the bitch may still refuse the male due to previous association of mating attempts with pain. Artificial insemination is the method of choice to ensure that these bitches conceive. Paradoxically, many bitches with vaginal strictures will whelp normally, probably due to the influence of the hormone relaxin at the time of labour. The stricture then returns preventing coitus during her next season. It is thought that these bitches have a lower pregnancy rate than normal bitches. This is believed to be due to improper drainage of the vagina with fluid retention in the anterior vagina and a low-grade vaginitis. Draining of the fluid using a speculum and antibiotic therapy appears to improve results.