1.1

Introduction

Back pain and/or pelvic pain are common complaints among pregnant women in Western countries and have been the subject of many publications, as reported in a review of 106 papers by Wu et al. (2004) and other review articles . Most earlier studies did not distinguish between pregnancy-related low back pain (affecting the lumbar spine area) and pelvic pain (affecting one or both sacro-iliac joints and/or symphysis pubis) possibly because it is not easy to discriminate between them from site, character, intensity and related disability of pain unless specific tests are used . In addition, the two syndromes are sometimes combined . From their review, Wu et al. reported that around 45% pregnant women suffered from pelvic girdle pain and/or low back pain, of whom 25% had severe pain and 8% had severe disability. The aetiology of the pain is still unclear though a number of factors have been investigated for association with pain. Strenuous work, previous low back pain and history of pregnancy-related pelvic girdle or low back pain were shown to be strong predictors of pregnancy-related back/pelvic pain . Conversely, maternal weight and weight gain were not related to back/pelvic pain . No relation between fatigability of back muscles and back pain was found by Dumas et al. in a longitudinal study with a small sample, but muscle dysfunction was associated to back pain by Sihnoven et al. . It has also been demonstrated that, in late pregnancy, motion in pelvic girdle joints is larger in women with pelvic girdle pain than in pain-free women by Mens et al. . Another study by Albert et al. found associations between both physical and psychosocial factors including parity, stress and poor job satisfaction, and pregnancy-related pelvic girdle pain.

Pregnancy-related back or pelvic girdle pain can reduce the ability of women to perform their regular work. It has been shown that women with more control over their work pace and breaks had better health by Wergeland and Stand and less back pain (Cheng et al. ). In late pregnancy, staying in a confined area and having restricted space were related to more severe back pain . These factors could be used as a basis for job adjustment for pregnant women.

It had been suggested that the increased number of claims in Western countries was related to the welfare system of these countries. In a comparative paper with a provocative title, “Is pelvic pain in pregnancy a welfare complaint?” Björklund and Bergström , showed that pregnancy-related pelvic pain is also frequent in countries with different social structures and socioeconomic conditions, like Tanzania and Zanzibar.

A few other studies have reported back and pelvic pain prevalence and their characteristics during pregnancy in African countries. In an early study, Nwuga reported that nearly 90% of the women in a sample of 99 upper class Nigerian women experienced some back pain during their pregnancies. In 80% of cases, the pain was rated as “mild” or “very mild”, but in 10% of cases, the pain was rated as “severe”. More recently, Ayanniyi et al. surveyed more than 1900 pregnant women attending antenatal clinics in Nigeria. A little more than half the women surveyed (52.5%) reported back pain, two third of them in the low back area, and about one quarter (24%) in the posterior pelvic area. The back pain group had on average higher gravidity than the pain-free group.

Previous work has associated back pain with heavy physical work in Western countries for men and pregnant women . Similar results were found in the African context in a study of 4001 Lesotho mothers with children under the age of 5 . The author reported approximately 10% of prevalence of severe back pain while approximately 50% of the women experienced moderate or mild low back pain. Severe low back pain was associated with intensive farm work, residing in a rural (rather than urban) area, and gravidity.

The objective of this exploratory study was to describe and underline the contrasts between African and Canadian pregnant women, and their living conditions. We also intended to evaluate how they compared on low back pain, a condition that seems common across all pregnant women everywhere in the world.

1.2

Method

1.3

Results

1.4

Discussion

The findings of this study showed differences between Beninese and Canadian women that are consistent with the differences between developed and developing countries; Canadian women were taller, heavier, they had less children, were more educated, most of them were employed and their household income was greater than Beninese women. Difference in weight between the two groups may be related to nutritional aspects between the two countries as recently reported in addition to the difference in stature. Concerning back pain, a larger percentage of Beninese women reported back pain, but the severity of disability measured with the O.D.I. was similar in the two groups, corresponding to moderate disability, though the score was slightly higher for the Benin group. Moreover, a greater percentage of Beninese women reported severe disability with an average O.D.I. score greater than for the Canadian group. It should be noted though that inclusion criteria introduced a bias for the Canadian group that tended to decrease the percentage of women with severe disability. However, the percentage of Canadian women reporting back pain and severe disability is comparable to the literature on Western pregnant women .

In the biopsychosocial model first proposed by Waddell 1993 , fear-avoidance beliefs and pain catastrophizing have been associated with perceived disability, including in a pregnant population . Perception, pain experience as well as beliefs and attitudes toward pain may vary in different cultures and countries, and affect reported disability. Cross-cultural differences in self-perceived dysfunction have been shown for chronic patients by Sanders et al. . This may also affect the results of this study, and should be investigated in future studies for the sub-Saharan context.

Some of the demographic differences between the two groups may explain the differences in back pain incidence. Though slightly younger, Beninese women had had one more child than Canadian women and were living with one more child at home on average. This reflects the difference in fertility rates between the two countries (5.5 births per woman in Benin, 1.6 in Canada) . Some studies have shown that women with higher parity had a higher incidence of back pain during pregnancy, but others found the opposite effect, or no effect at all .

Another difference standing out was the socioeconomic status and level of education of the subjects. Low socioeconomic status and low education are often associated with strenuous physical work. Of the 18 Beninese women who reported an occupation other than housewife, ten were in retail sales. In sub-Saharan Africa, retail sales are almost exclusively performed by women and girls. It is a physically demanding occupation in most cases, because the merchant carries the goods on her head. In the case of ambulant merchants, goods are carried throughout the working day, and they are lowered for each sale and lifted again to reposition them on the head. The loads carried are diverse and can be very high, about 30% of body weight and sometimes considerably more. Housewives in Benin also perform a number of physically demanding tasks including carrying heavy loads like water. Many tasks also involve substantial levels and durations of bending (cleaning the floor, cooking on the floor, etc.). In addition, Beninese women reported working on average 18 hours more per week than Canadian women. Strenuous physical work has been strongly associated with back pain during pregnancy . Future research should study some of the tasks performed by Beninese women, e.g. carrying loads on the head, and how they affect spinal mechanics. Furthermore, none of the Beninese women reported consuming tobacco while more than one-third of the Canadian sample consisted of smokers or ex-smokers. Smoking has been shown to be positively associated with back pain (smokers are more likely to have back pain than non-smokers), although Wu et al. considered this relation as weak. The data also showed that only one-third of Beninese women reported back pain before this pregnancy while two-thirds of Canadian women did. Previous back pain has been strongly associated with back pain during pregnancy and even shown to be the best predictor of future back pain .

When looking at the group with the highest disability scores on O.D.I. ( Table 3 ), it appears that, in both subgroups, women were on average heavier than the whole group. High maternal weight has been shown to be a risk factor for lumbo-pelvic pain in some studies and this relation was considered as positive but weak by Wu et al. .

Other factors differ between the two groups. In the Beninese subgroup, women had a greater parity by almost 1 than for the total group, while it was the opposite in the Canadian subgroup. On the other hand, the Canadian subgroup subjects worked about 8 more hours per week than the total group, but there was no difference in the Beninese group. Only one subject reported previous back pain in the Beninese subgroup while all subjects did in the Canadian one. Though the samples are small, these findings seem to indicate that severe and disabling back pain could be caused by distinct factors in Beninese and Canadian women.

1.5

Conclusion

The results of this exploratory study showed that, as expected, there were large differences between the Beninese and Canadian groups of pregnant women due to the differences between the two countries. Beninese women were more likely to be self-employed or housewives, while Canadian women were more likely to be employed. Beninese women worked for 18 hours more per week, and they had on average one more child at home. A higher percentage of Beninese (83%) women reported back pain during pregnancy, as opposed to 58% for Canadian women. Again, a higher percentage of Beninese women reported at least severe disability, 33%, versus 14% for Canadian women. The disability scores were also slightly higher for the Beninese women, but the average O.D.I. score for both groups were in the “moderate disability” range.

These results must be taken with care considering the relatively small samples, and the potential errors in questionnaire data due to translation and lack of cultural adaptation of the O.D.I. Considering the large percentage of Beninese women reporting back pain and the high disability scores reported in this exploratory study, further investigation of this problem should be considered. Avenues for future research may include developing and testing instruments to evaluate back pain and pelvic pain in Sub-Saharan pregnant women and evaluating the workload of certain groups of pregnant women and other risk factors for back pain.

Disclosure of interest

The authors declare that they have no conflicts of interest concerning this article.

Acknowledgements

The authors want to acknowledge the contributions of the assistants who conducted the data collection, Juliette Assogba and Florence Dansou in Benin, and Sarah Parisi and Heather Manley in Canada, as well as Rose Gohoun who entered the data from Benin, and the subjects who participated in the two studies.