How widespread is obstetric fistula? It has been estimated that, worldwide, fistulas occur in one or two cases per 1,000 deliveries (11, 12). The actual prevalence of fistulas is not known, however. No comprehensive survey has been conducted.

Based on the number of women seeking treatment, the World Health Organization (WHO) has estimated that over 2 million women are living with untreated obstetric fistulas (39). This estimate probably is far too low, primarily because many women with fistulas do not seek treatment (29).

Obstetric fistula appears to be most common in sub-Saharan Africa and South Asia. One study estimated the minimum incidence of obstetric fistula in rural areas of sub-Saharan Africa to be 33,450 cases per year—many more than has been estimated based on hospital reports (64). Obstetric fistula could also be widespread in parts of the Near East and North Africa, although the lack of studies precludes accurate estimates (44).

Obstetric fistula is rare in the developed world because emergency obstetric care is readily available. When fistulas occur at all, they usually are the result of cervical cancer, radiation therapy, or injuries sustained in surgery, and are treated without delay (71).

Before the 20th century, however, obstetric fistulas were common in Europe and North America (51, 81). Then, as in many developing countries today, women often married and became pregnant at young ages, many were undernourished, few had adequate access to skilled attendants, and most lacked good-quality medical care (71).

While the immediate causes of obstetric fistula in developing countries are obstructed labor and lack of prompt access to emergency obstetric care, pervasive poverty is often a root cause. Studies show that fistula patients tend to live in remote areas and to be impoverished (41, 64)—factors typically associated with inadequate health care during pregnancy and delivery and thus with increased risk for obstetric complications (22).

With less access to obstetric care, rural women are more likely to suffer fistulas than urban women (47, 64). Among rural women those with lower social and economic status are more likely than others to suffer fistulas and other obstetric problems. For example, in Nigeria in a study among 50 rural hospitalized fistula patients and a comparison group of 50 women without fistula living in a nearby village, 40% of fistula patients reported having no schooling compared with 14% of the comparison group (41). The same study found that the husbands of women with fistula were likely to work as farmers, tradesmen, or cattle herdsmen, while the husbands of the women in the village group were likely to be office workers, administrators, or the like.

Recent country-level assessments conducted as part of a new international campaign to address fistula (see Case Study: International Campaign Strives To End Fistula) confirm that most reported cases of obstetric fistula occur among rural, low-status women. The prevalence of untreated obstetric fistula appears closely associated with lack of skilled assistance during delivery and lack of access to emergency obstetric care, as well as the shortage of capacity for fistula repair (57, 63).

A young couple at their wedding in Nepal. Where early marriage is common, women often become pregnant during adolescence. Encouraging later marriage and delayed childbearing can help reduce the incidence of adolescent pregnancies and their risks.

Although obstructed labor and obstetric fistulas can occur at any age during the childbearing years, adolescent women are at particular risk, especially where early marriage is common. In parts of sub-Saharan Africa, for example, many women become pregnant soon after menarche occurs, before a woman’s pelvis is fully developed for childbearing. In Nigeria more than one-quarter of 241 fistula patients studied had become pregnant before age 15, while more than one-half had become pregnant before age 18 (2). In many developing countries many adolescent women are undernourished, stunted, and underweight—factors that compound the risks of early pregnancy (43, 63).

While most fistula cases stem from obstetric causes, others result from direct trauma caused by rape or other sexual abuse (38, 46, 48, 52, 74). At the Addis Ababa Fistula Hospital, for example, 91 of 7,200 cases over a six-year period, or about 1.2%, were caused by rape or other sexual abuse (38).

Fistula caused by rape and other sexual abuse probably is far more common than this statistic suggests, because many victims do not seek treatment, lacking access and often fearing stigmatization (25). In situations of war and civil unrest, when rape is usually far more common, the proportion of fistulas caused by sexual abuse can increase substantially (25, 72).

In some areas harmful traditional practices, such as female genital cutting (FGC), also add, either directly or indirectly, to the risk for fistula and other gynecological and obstetric complications (56, 71). FGC is usually carried out under unsanitary conditions, often removing large amounts of tissue and possibly causing the vaginal outlet and birth canal to become scarred and constricted (27).

One well-documented practice during obstructed labor, “gishiri cutting,” occurs primarily in northern Nigeria (23, 53, 69). A traditional birth attendant or barber uses a sharp instrument—a knife, razor blade, or piece of broken glass, for example—to make a series of random cuts in the vagina in an attempt to remove the obstruction and make way for the baby. This practice can directly injure the bladder or urethra and may explain as many as 15% of fistula cases in northern Nigeria (71).