Obstetric fistula (fistula from here on) is an “abnormal opening between a woman’s vagina and bladder and/or rectum, through which her urine and/or faeces continually leak” [1]. Fistulae are generally caused by long obstructed labours. Such labours can last for days and in most cases the baby dies [2, 3]. During an obstructed labour, the baby’s head becomes lodged in the pelvis and the pressure from the head can cut off the blood flow to the surrounding tissues causing them to necrotize and form a hole. Surgical repair of fistula is possible even if the fistula has been present for some time [1]. Closure rates of 85-95% for those operated on have been reported in a number of case series [4]. However, it is unclear how many women are considered “inoperable” before an operation is attempted.

The potential consequences for women who suffer from fistula are social, emotional and physical [3]. The woman may have sores on her genitals due to urine dermatitis, be unable to have sex, and stop or have irregular periods [4]. These factors, and the associated smell, may lead to social problems, loss of ability to work and estrangement from spouses, family and society [4]. There is also limited evidence of an increased risk of depression [5]. The time and resources required by women to keep clean has also been found to have a major impact on women’s lives [6].

Fistulae are thought to be relatively rare globally, with most cases originating in low income countries in women lacking access to intrapartum care [2]. The WHO estimates two million women have fistula globally [1], but do not state their reliable sources. There are few reliable prevalence estimates because of fistula’s rarity and the remoteness of the areas where sufferers tend to live. Most studies stating a prevalence of fistula are based on self reports, personal communications with surgeons, studies from advocacy groups or reviews of hospital services without denominators [7]. A commonly cited statistic, that fistula occurs in 200–500 per 100,000 deliveries, originates from a personal communication with a fistula surgeon working in East Africa [8]. Incidence in the MOMA study [9] of eight centres in six countries in west Africa is 10 per 100,000 pregnancies overall (denominator 19,342 pregnancies) and 120 in rural areas (denominator 1,543 pregnancies). Community-based prevalence estimates from Gambia [10] are 96 per 100,000 women of reproductive age (denominator 1038 women) and from Ethiopia [11] (treated and untreated) are 203 per 100,000 women of reproductive age (denominator 27,090 women). We did not find estimates for South Sudan or for Sudan before separation.

Because fistulae are rare, conducting a household survey to estimate prevalence precisely would involve an extremely large sample size and would require high specificity of questions or approaches to ascertaining fistula. The Key Informant Method (KIM) offers an alternative method for estimating the prevalence of rare conditions, including childhood blindness and childhood disability [12, 13]. Key informants are trained across a defined geographic area to identify all potential cases of a condition. These cases are then examined by a clinician to verify case status. The prevalence of the condition is estimated as the number of cases divided by the population at risk in the area.

Following 50 years of war, South Sudan became independent in June 2011. Its population is 8.26 million [14] and is one of the world’s least developed countries. A recent report found 33 functioning hospitals in the whole country, with only 16% of all health facilities having electricity [15]. It is estimated that there is only one doctor per 100,000 people in South Sudan; substantially lower than the 20 per 100,000 recommended by WHO [16]. South Sudan reports some of the worst health statistics in the world, with an Infant Mortality Rate of 102 per 1000 live births and a Maternal Mortality Ratio of 2054 per 100,000 live births [14]. Only 19% of women are estimated to give birth with a skilled birth attendant, 12% to give birth in health facilities, and 13% to use antenatal care [17]. For these reasons, South Sudanese women are considered to be at high risk for obstetric morbidities, including fistula.

This work was conducted with three aims: to understand the existing availability of fistula services in South Sudan, to assess whether KIM is an effective method for finding women with fistula, and to estimate the prevalence of fistula in women of reproductive age in a region of South Sudan.

We estimated a prevalence of fistula of at least 30 per 100,000 women of reproductive age in WBG, suggesting that if the results are extrapolated, there are at least 619 (128–1807) untreated women in South Sudan. However, the findings from our small sample in WBG are unlikely to be generalisable to the whole country given the wide range of access to maternity services from state to state. In 2006 in WBG, 13.8% of women had a skilled attendant present at their birth, compared to the 4.9% in Eastern Equatoria [19] and 12% in the whole country [14]. The risk of obstructed labour and consequently of fistula may vary between regions. Therefore, we cannot be confident that this is a true reflection of the minimal prevalence across the country.

The quality and capacity of current fistula repair services are inadequate to meet the needs of the population. This is within a context of limited health services in general and particularly for women. The campaign system has been a good short term measure, however it has not provided consistent or equitable care and is insufficient to cope with the backlog of cases, with nearly as many cases on waiting lists as have been treated in the last six years. Clinicians’ and policy makers within South Sudan described the key barriers to providing consistent hospital-based services, which would require investment in human resources and facilities to overcome. There are currently clinicians who have been trained to carry out basic fistula repairs and these skills could be better utilised and supported to provide a service for South Sudan. Any resources used for fistula service development have to be carefully weighed up against the greater numbers of people who are without the most basic of health services. This is particularly true in light of the relatively low prevalence estimates obtained in our study. Nonetheless there is a need to facilitate the access of these women with an unmet need for services; awareness of fistula could be raised among the population as part of the overall package of obstetric-related health messages.

Our estimated prevalence of 30 per 100,000 is considerably lower than previous population-based estimates [8, 10, 11]. Given the poor maternal health indicators in South Sudan, one would expect at least as high a prevalence as other regions of Sub-Saharan Africa. There are several potential explanations for our finding.

Our estimate could be correct, with others being incorrect. Many of the prevalence estimates reported in the literature are not based on epidemiological studies and as a result, are likely to be inaccurate; if publications are advocating to address the issue, they may well have overestimated the prevalence. Alternatively, our estimates may be correct but unrepresentative as it is possible that our selected area was too close to Wau, and therefore the communities that we visited would have had greater access to maternal services and therefore a decreased risk of fistula. However, the communities were one hour’s drive with good vehicles from the city, which would not be possible for most women in the communities, and the roads used were only completed in 2010. Finally, it is also possible that as South Sudan reports having the highest maternal mortality in the world and has high rates of all cause mortality, the women with obstructed labour did not survive long enough to present with fistula.

Alternatively, it is possible we underestimate the prevalence for a number of reasons. First, the KIM may not be an effective method for complete ascertainment of cases of fistula, and we did not find all the eligible cases. KIM has been validated for use for other rare conditions including childhood disability and childhood blindness [12, 13], but while these are often stigmatizing conditions, it may be that mothers will bring children for assessment but not come themselves. Previous work on women with fistula has emphasised their isolation from family, friends and community [2, 20, 21]. This could mean that women were “hidden” and unable to be identified. Our key informants particularly the CBDs, were key members of their community and we feel it would be unlikely that in close communities women with fistula would be completely hidden. It is also possible that women with fistula were identified but refused to attend verification. Again, the training of the key informants was designed to ensure that women were supported, reassured about confidentiality and given information about treatment. The women with fistula who did come forward did not report stigma as a major issue.

Since women from outside the target area presented for verification, this suggested to us that messages were effectively communicated across a wide area and some women at least were willing to come forward. Additionally, subsequent research conducted in the same area by a team with a social anthropologist identified further women in areas outside of the one we studied, but no additional women were found in the region we studied.

Finally the prevalence could be influenced by inaccurately estimating the denominator, which was obtained from recent surveys conducted by the government. There is some debate about how accurate the household surveys were. However even if we overestimated the population by 10,000 people (23%), this would still have only resulted in an estimate of 40 per 100,000 women of reproductive age, which does not raise the prevalence by much.

This is the first time that KIM has been used to identify maternal morbidities, and we believe that it is a promising tool for the future. We have shown that it is possible to find women with fistula using a KIM. It has the advantage of being much faster and cheaper than household surveys, as well as benefiting from community involvement. However it has the limitation of having to rely on key informants of varying ability to find the women and the possibility of missing eligible cases. The next step is to use this method in further studies, in other regions of South Sudan and Sub-Saharan Africa. Complementary qualitative data that have been collected from the key informants and women with fistula will offer further insights to improve the key informant methodology. This methodology has the potential to become a practicable method for estimating the prevalence of women with fistula, which will be invaluable in planning future services and ensuring equitable access. Further use of this method in other regions of the world, possibly in contexts where other methods are used as well, would enable the production of comparable estimates, to identify whether the low prevalence found by this study in South Sudan is accurate or a result of methodological limitations. It has the added advantage of having a clinincal assessment which confirms the diagnosis. It is well understood that using women’s self-reported morbidity will over estimate the prevalence of rare conditions, unless the specificity of the questions is very, very high.

This study was a preliminary assessment of fistula in a region of South Sudan, identifying limited services and quantifying the potential unmet need. This provides important information for future policy and service development; to ensure that fistula is integrated with other services, existing skills are built on and women with fistula are proactively identified to receive services. Any service developed needs to be considered within the context of limited resources and that current demand is less than may have been expected.

Obstetric fistula is a severe condition which can have devastating consequences for a woman’s life and is generally associated with poor obstetric services. Despite many publications, little is actually known about the overall prevalence of fistula as there are very few population-based studies looking at the prevalence that include a physical examination. Despite awareness at the government level, the routine fistula repair services available to the women of South Sudan do not meet the needs of the population. This is within a context of overall poor medical services particularly for women. The pilot study we conducted suggests that KIM can be used to identify women that have fistula in the community, however this is the first time this methodology has been used for determining the prevalence of obstetric fistula and more research should be conducted to show its usefulness in other settings. Within a context of poor reporting of fistula within Sub-Saharan Africa, our findings suggest that fistula may be less common in South Sudan than other regions of Sub-Saharan Africa.

Joint first author: Samantha Fox.