Are pregnant women prioritized for bed nets? An assessment using survey data from 10 African countries

INTRODUCTION

Malaria in pregnancy is a major public health concern, contributing to high rates of maternal and newborn morbidity and mortality. More than 30 million pregnant women reside in malaria-endemic areas of Africa, where Plasmodium falciparum infection in pregnancy is associated with low neonatal birth weight and where the infection contributes to roughly 11% of neonatal deaths.¹ One of the most serious and potentially deadly consequences of malaria during pregnancy is maternal anemia, which presents even in women with asymptomatic malaria infection and in those with undetectable infection by blood smear due to mass sequestration in the placenta.² In some parts of the world, malaria infection during pregnancy contributes directly to 25% of all maternal deaths.³

Because of the significant impact of this disease on pregnant women and newborns, in 2000, multiple African countries south of the Sahara pledged to fight malaria in pregnancy with insecticide-treated nets (ITNs), intermittent preventive treatment of malaria in pregnancy (IPTp), and improved case management.⁴ Three years later, the World Health Organization released “A Strategic Framework for Malaria Prevention and Control During Pregnancy in the African Region” to develop a standardized method for preventing and controlling malaria during pregnancy.⁵ By 2007, 39 African countries had incorporated part, or all, of this framework into their national malaria control plans.⁶ However, the extent to which these new strategies have been deployed or have reduced maternal malaria is uncertain.

According to an analysis by Stenberg and colleagues (2013), scaling up ITN coverage and IPTp and ensuring availability of appropriate malaria treatment could prevent 153 million episodes of malaria by 2035, saving US$5 billion in drug costs alone and US$280 million in outpatient visits.⁷ Additionally, studies have shown that targeting pregnant women and infants during ITN distribution campaigns is an effective method of reducing all-cause post-neonatal mortality.^8–11

Timing of ITN use during pregnancy is important. While the effects of malaria infection in the first trimester are largely unknown, risk of miscarriage seems to increase compared with women who become infected later in pregnancy, especially among women who develop clinical malaria.¹² The highest rates of infection, severe disease, and fetal impairment occur in the second and third trimesters, but IPTp cannot be given to pregnant women in the first trimester due to potential teratogenicity and possible fetal death.^12,13 These factors make it important for women to attend antenatal care (ANC) to obtain an ITN early during pregnancy.^3,12,14

Since 2009, there has been a move away from prioritizing vulnerable populations (such as children under 5 and pregnant women) during net distribution to a universal coverage paradigm.¹⁵ These campaigns strive to provide every household with 1 net per 2 people, or 1 net per sleeping space, regardless of household composition (that is, number of pregnant women and children). This strategy allows countries to rapidly attain high levels of net coverage throughout a region and includes households that do not have a pregnant woman or young children; however, in order to maintain protection across the population, there needs to be additional, focused distribution targeting pregnant women and children to ensure ITN coverage at critical fetal and infant growth stages.¹⁶ Within the context of universal coverage campaigns, it is unclear whether pregnant women continue to be prioritized for ITN use, in terms of nets allocated at the national level that are specifically targeted for ANC distribution as well as net allocation within the household.

In this article, we focus on assessing available survey data from 10 countries in Africa to determine whether and to what extent pregnant women are prioritized within the household for ITN use. By applying the newly recommended indicators of access to an ITN within the household to this group, it is possible to see more precisely where pregnant women are using nets.¹⁷ These data provide a better understanding of net use behavior, differentiating between those who do not use a net because they do not have access to one versus those who have access to a net and do not use one for behavioral reasons.

RESULTS

The number of households surveyed ranged from 5,895 (Nigeria) to 24,825 (Malawi). The median proportion of those surveyed who were pregnant was 9%, ranging from 7% (Madagascar and Rwanda) to 11% (Nigeria) (Table 1).

ITN Use by Pregnant Women Versus Other Household Members

Net use was generally higher among pregnant women and non-pregnant WRA than among other household members. There was no significant difference in use between pregnant women and WRA in any country, regardless of whether the household had sufficient nets for the entire family. In households with at least 1 ITN, a significantly higher proportion of pregnant women than “other” household members (comprising children through 14 years of age, men ages 15–49 years, and adults over 49 years) used nets in 8 of the 10 countries included in the analysis (Liberia, Malawi, Mozambique, Nigeria, Rwanda, Senegal, Tanzania, and Uganda). In households with universal coverage, a significantly higher proportion of pregnant women than other household members used nets in Malawi, Rwanda, Senegal, Tanzania, and Uganda (Table 2).

In all countries, the predicted probability of ITN use by pregnant women was significantly higher than the probability of ITN use by children ages 5–14, men ages 15–49, and individuals over 49 after controlling for other household variables. See, for example, Figure 1, showing data from Liberia. (For data from other countries, see Supplemental Figures 1–5). Pregnant women were also more likely to use an ITN than children under 5 in all but 4 countries (Nigeria, Senegal, Tanzania, and Zimbabwe). See Figure 2 for sample data from Senegal and Supplemental Figures 6–8 for data from Nigeria, Tanzania, and Zimbabwe. In all countries, ITN use by pregnant women was not significantly different than for non-pregnant WRA when controlling for other household variables.

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FIGURE 1.

Adjusted Probability of ITN Use by Risk Group, Liberia, 2011

Abbreviations: ITN, insecticide-treated net; WRA, (non-pregnant) women of reproductive age.

Pregnant women were significantly more likely to use an ITN than children under 5, children ages 5–14, men ages 15–49, and adults over 49 years. ITN use by pregnant women was not significantly different than use by non-pregnant WRA. Error bars indicate 95% confidence intervals.

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FIGURE 2.

Adjusted Probability of ITN Use by Risk Group, Senegal, 2010

Abbreviations: ITN, insecticide-treated net; WRA, (non-pregnant) women of reproductive age.

Pregnant women were significantly more likely to use an ITN than children ages 5–14, men ages 15–49, and adults over 49 years. ITN use by pregnant women was not significantly different than use by non-pregnant WRA or children under 5. Error bars indicate 95% confidence intervals.

Pregnant women and non-pregnant women of reproductive age were significantly more likely to use a bed net than other household members.

DISCUSSION

In this study, we compared ITN use by pregnant women in households with and without universal net coverage (that is, 1 net per 2 people) to determine whether lack of household access to ITNs was the main reason for non-use of nets by pregnant women. The results of this study demonstrate that across the 10 study countries, pregnant women as well as non-pregnant women of reproductive age were more likely to have used an ITN the night before the survey than other household members. In addition, an even higher proportion of pregnant women who lived in a household with universal coverage than pregnant women in households without universal coverage used nets. This suggests that both non-pregnant women of reproductive age and pregnant women are being prioritized within the household and that non-use is indeed more related to lack of access to an ITN rather than due to a behavioral issue.

Greater access to nets, however, does not always translate into greater use by pregnant women; behavior change communication (BCC) is still needed to ensure prioritization of and use by pregnant women. In some countries that recently had a net distribution campaign (such as in Madagascar and Tanzania, which had major distributions between 2009–2010 and 2010–2011, respectively), households were more likely to report higher net ownership, thus reducing the use:access gap.¹⁹ But these countries were not always the most likely to prioritize pregnant women, and some countries with low universal net coverage rates are more likely to prioritize pregnant women for net use. For example, in Nigeria only 9.8% of households reported having universal coverage, yet pregnancy was a significant predictor of net use when compared with children ages 5–14, men ages 15–49, and individuals over 49. This demonstrates that pregnant women were prioritized at the net distribution level, the household-allocation level (which also includes prioritization of non-pregnant women of reproductive age), or both. In early 2009, Nigeria embarked on a universal coverage campaign to distribute LLINs and spread messaging about malaria prevention, including in ANC clinics.²⁰ Such BCC messages promoting ITN use for pregnant women have been part of national communication strategies since 2003,⁵ and it appears that households and communities have internalized them.²¹

This study is not the first to note prioritization of ITN use by pregnant women in recent years. Data from as early as 2004 demonstrate that children and women of reproductive age were more likely to use ITNs, especially in households with more nets per people, in African countries including Tanzania and Zambia.^21,22 Additionally, these nets were in better condition than those used by older children and adults.²¹ In contrast, data from 15 national surveys between 2003–2006 showed that pregnant women had less access to ITNs than other household members and were not prioritized within the household.²³

The upward trend has led to an overall increase in net use by pregnant women, which can be attributed to increased intra-household net access as well as prioritization of all women of reproductive age by those household members responsible for net use and allocation decisions. In some countries evaluated in this study, net use by pregnant women has exceeded RBM's 2010 goal of 80% use in households that report universal coverage.^11,24 However, in households owning less than 1 net per 2 people, no countries met this goal.

Insufficient access to nets for pregnant women can be due to many factors, including local- and national-level stockouts of ITNs at ANC clinics, delays in ANC attendance, and insufficient provider training.^11,25 These problems call for additional monitoring and evaluation of the supply chain and accountability both nationally and locally as well as improving ANC distribution systems to ensure consistent access to nets by pregnant women.

CONCLUSION

Lack of access to bed nets appears to be the more important factor for non-use of ITNs by pregnant women in the 10 African countries analyzed in this study, rather than behavioral issues. However, it would be premature to assume that increasing net access alone would solve the problem completely, particularly since shortages and gaps in coverage are inevitable at national and local levels. Strategies such as behavior change communication to promote prioritization of pregnant women at both national program and household levels are necessary to achieve the coverage goals set by RBM for pregnant women. Such strategies can increase pregnant women's access to ITNs, further strengthen the culture of net use in countries in general, and continue to encourage net use specifically by pregnant women at all stages of pregnancy.