Malaria infection during pregnancy: intrauterine growth retardation and preterm delivery in Malawi

Ghana's Livelihood Empowerment Against Poverty (1000) Program Seasonally Impacts Birthweight: A Difference-in-Differences Analysis

Objectives: Low birthweight (LBW) prevalence remains high in African countries and evidence of cash transfer impacts on birthweight, particularly by season of infant birth, is limited. This study examines overall and seasonal cash transfer impacts on LBW in rural Ghana. Methods: Data come from a longitudinal, quasi-experimental impact evaluation of the Livelihood Empowerment Against Poverty (LEAP) 1,000 unconditional cash transfer program for impoverished pregnant or lactating women in rural districts of Northern Ghana. LEAP1000 program impacts on average birthweight and LBW were estimated for a multiply imputed sample of 3,258 and a panel sample of 1,567 infants using differences-in-differences models and triple difference models to assess impacts by season. Results: LEAP1000 decreased LBW prevalence by 3.5 and 4.1 percentage points overall and in the dry season, respectively. LEAP1000 increased average birthweight by 94, 109, and 79 g overall, in the dry season, and in the rainy season, respectively. Conclusion: Our findings of positive LEAP1000 impacts on birthweight across seasons and on LBW in the dry season demonstrate the need to take seasonal vulnerabilities into account when designing and implementing programs for rural populations in Africa.

A Scoping Review of Preterm Births in Sub-Saharan Africa: Burden, Risk Factors and Outcomes

Preterm births (PTB) are the leading cause of neonatal deaths, the majority of which occur in low- and middle-income countries, particularly those in Sub-Saharan Africa (SSA). Understanding the epidemiology of prematurity is an essential step towards tackling the challenge of PTB in the sub-continent. We performed a scoping review of the burden, predictors and outcomes of PTB in SSA. We searched PubMed, Embase, and three other databases for articles published from the database inception to 10 July 2021. Studies reporting the prevalence of PTB, the associated risk factors, and/or its outcomes were eligible for inclusion in this review. Our literature search identified 4441 publications, but only 181 met the inclusion criteria. Last menstrual period (LMP) was the most commonly used method of estimating gestational age. The prevalence of PTB in SSA ranged from 3.4% to 49.4%. Several risk factors of PTB were identified in this review. The most frequently reported risk factors (i.e., reported in ≥10 studies) were previous history of PTB, underutilization of antenatal care (<4 visits), premature rupture of membrane, maternal age (≤20 or ≥35 years), inter-pregnancy interval, malaria, HIV and hypertension in pregnancy. Premature babies had high rates of hospital admissions, were at risk of poor growth and development, and were also at a high risk of morbidity and mortality. There is a high burden of PTB in SSA. The true burden of PTB is underestimated due to the widespread use of LMP, an unreliable and often inaccurate method for estimating gestational age. The associated risk factors for PTB are mostly modifiable and require an all-inclusive intervention to reduce the burden and improve outcomes in SSA.

Immunohistopathological changes in the placenta of malaria-infected women in unstable transmission setting of Aligarh

INTRODUCTION

Pregnant women are more susceptible to malaria due to a combination of physiological and immunological changes. The infection may even affect the growth and survival of the foetus, which mainly occur when parasite enters the placenta. The sequestration of infected erythrocytes may trigger the host response, leading to placental inflammation and altered development, affecting the structure and nutrient transport of placenta. These factors collectively impair placental functions and affect foetal growth.

METHODS

Pregnant women with peripheral parasitaemia for P. falciparum and P. vivax (20 each) were included in the present study, along with 15 age-matched uninfected healthy pregnant women. Placentae were analysed for the presence of local parasitaemia along with pathological lesions caused due to the parasite. Immunohistochemical staining for CD20, CD45 and CD68 cells was performed for examining the specific leucocytes in the intervillous space of the placenta.

RESULTS

Of the 20 individuals with P. falciparum, only seven placentae showed parasitaemia, whereas individuals with P. vivax showed no placental infection. The pathological changes observed in the P. falciparum-infected placenta include syncytial knotting, excess fibrinoid deposition, syncytiotrophoblast necrosis, syncytial rupture, thickening of trophoblast basement membrane and increased collagen deposition. Immunohistochemical staining showed a significant increase in B cells (CD20), leucocytes (CD45) and monocytes and macrophages (CD68) in the P. falciparum-infected placenta (p < 0.0001).

DISCUSSION

The result implies that P. falciparum is responsible for pathological alterations in placenta, affecting the nutrient transport across placenta and foetal growth. The immune cells also migrate to the placenta and accumulate in the intervillous space to show humoral and cell-mediated immunity against the parasite.

Polymorphic Molecular Signatures in Variable Regions of the Plasmodium falciparum var2csa DBL3x Domain Are Associated with Virulence in Placental Malaria

The Plasmodium falciparum protein VAR2CSA allows infected erythrocytes to accumulate within the placenta, inducing pathology and poor birth outcomes. Multiple exposures to placental malaria (PM) induce partial immunity against VAR2CSA, making it a promising vaccine candidate. However, the extent to which VAR2CSA genetic diversity contributes to immune evasion and virulence remains poorly understood. The deep sequencing of the var2csa DBL3X domain in placental blood from forty-nine primigravid and multigravid women living in malaria-endemic western Kenya revealed numerous unique sequences within individuals in association with chronic PM but not gravidity. Additional analysis unveiled four distinct sequence types that were variably present in mixed proportions amongst the study population. An analysis of the abundance of each of these sequence types revealed that one was inversely related to infant gestational age, another was inversely related to placental parasitemia, and a third was associated with chronic PM. The categorization of women according to the type to which their dominant sequence belonged resulted in the segregation of types as a function of gravidity: two types predominated in multigravidae whereas the other two predominated in primigravidae. The univariate logistic regression analysis of sequence type dominance further revealed that gravidity, maternal age, placental parasitemia, and hemozoin burden (within maternal leukocytes), reported a lack of antimalarial drug use, and infant gestational age and birth weight influenced the odds of membership in one or more of these sequence predominance groups. Cumulatively, these results show that unique var2csa sequences differentially appear in women with different PM exposure histories and segregate to types independently associated with maternal factors, infection parameters, and birth outcomes. The association of some var2csa sequence types with indicators of pathogenesis should motivate vaccine efforts to further identify and target VAR2CSA epitopes associated with maternal morbidity and poor birth outcomes.

The impact of gravidity, symptomatology and timing of infection on placental malaria

Background

Placental malaria is associated with increased risk of adverse perinatal outcomes. While primigravidity has been reported as a risk factor for placental malaria, little is known regarding the relationship between gravidity, symptomatology and timing of Plasmodium falciparum infection and the development of placental malaria.

Methods

The aim of this study was to investigate the relationship between the development of placental malaria and gravidity, timing of infection, and presence of symptoms. This is a secondary analysis of data from a double-blind randomized control trial of intermittent preventive therapy during pregnancy in Uganda. Women were enrolled from 12 to 20 weeks gestation and followed through delivery. Exposure to malaria parasites was defined as symptomatic (fever with positive blood smear) or asymptomatic (based on molecular detection of parasitaemia done routinely every 4 weeks). The primary outcome was placental malaria diagnosed by histopathology, placental blood smear, and/or placental blood loop-mediated isothermal amplification. Multivariate analyses were performed using logistic regression models. Subgroup analysis was performed based on the presence of symptomatic malaria, gravidity, and timing of infection.

Results

Of the 228 patients with documented maternal infection with malaria parasites during pregnancy, 101 (44.3%) had placental malaria. Primigravidity was strongly associated with placental malaria (aOR 8.90, 95% CI 4.34–18.2, p < 0.001), and each episode of malaria was associated with over a twofold increase in placental malaria (aOR 2.35, 95% CI 1.69–3.26, p < 0.001). Among multigravid women, the odds of placental malaria increased by 14% with each advancing week of gestation at first documented infection (aOR 1.14, 95% CI 1.02–1.27, p = 0.02). When stratified by the presence of symptoms, primigravidity was only associated with placental malaria in asymptomatic women, who had a 12-fold increase in the odds of placental malaria (aOR 12.19, 95% CI 5.23–28.43, p < 0.001).

Conclusions

Total number of P. falciparum infections in pregnancy is a significant predictor of placental malaria. The importance of timing of infection on the development of placental malaria varies based on gravidity. In primigravidas, earlier asymptomatic infections were more frequently identified in those with placental malaria, whereas in multigravidas, parasitaemias detected later in gestation were associated with placental malaria. Earlier initiation of an effective intermittent preventive therapy may help to prevent placental malaria and improve birth outcomes, particularly in primigravid women.

A stitch in time: narrative review of interventions to reduce preterm births in Malawi

Background

The rising rate of preterm births (PTBs) is a global concern, and Malawi has a high rate of PTBs (10.5%). The resulting neonatal and under-5 mortality, morbidity and lifelong disability represent a significant loss of human potential affecting individuals, families and society as a whole. This study aims to review the literature to determine the risk factors for PTB in Malawi and to identify effective interventions to prevent PTBs.

Methods

A literature search yielded 22 studies that were categorized according to risk factors implicated for PTBs and health interventions to reduce the risks.

Results

The study has shown that maternal pregnancy factors, infections, nutrition, anaemia and young maternal age are the main causes and risk factors of PTBs in Malawi. The literature revealed no evidence of community-based interventions for reducing the rates of PTBs in Malawi.

Conclusions

Any successful effort to reduce the rate of PTBs will require a multisector, multilevel strategy targeted at the community, homes and individuals as a package to improve the education, nutrition and reproductive health of girls and women as well as focus on improving the delivery of antenatal services in the community.

Determinants of preterm birth among mothers who gave birth in East Africa: systematic review and meta-analysis

BACKGROUND

Preterm birth (PTB) can be caused by different factors. The factors can be classified into different categories: socio demographic, obstetric, reproductive health, medical, behavioral and nutritional related. The objective of this review was identifying determinants of PTB among mothers who gave birth in East African countries.

METHODS

We have searched the following electronic bibliographic databases: PubMed, Google scholar, Cochrane library, AJOL (African journal online). Cross sectional, case control and cohort study published in English were included. There was no restriction on publication period. Studies with no abstracts and or full texts, editorials, and qualitative in design were excluded. Funnel plot was used to check publication bias. I-squared statistic was used to check heterogeneity. Pooled analysis was done by using fixed and random effect model. The Joanna Briggs Critical Appraisal Tools for review and meta-analysis was used to check the study quality.

RESULTS

A total of 58 studies with 134,801 participants were used to identify determinants of PTB. On pooled analysis, PTB was associated with age < 20 years (AOR 1.76, 95% CI: 1.33-2.32), birth interval less than 24 months (AOR 2.03, 95% CI 1.57-2.62), multiple pregnancy (AOR 3.44,95% CI: 3.02-3.91), < 4 antenatal care (ANC) visits (AOR 5.52, 95% CI: 4.32-7.05), and absence of ANC (AOR 5.77, 95% CI: 4.27-7.79). Other determinants of PTB included: Antepartum hemorrhage (APH) (AOR 4.90, 95% CI: 3.48-6.89), pregnancy induced hypertension (PIH) (AOR 3.10, 95% CI: 2.34-4.09), premature rupture of membrane (PROM) (AOR 5.90, 95% CI: 4.39-7.93), history of PTB (AOR 3.45, 95% CI: 2.72-4.38), and history of still birth/abortion (AOR 3.93, 95% CI: 2.70-5.70). Furthermore, Anemia (AOR 4.58, 95% CI: 2.63-7.96), HIV infection (AOR 2.59, 95% CI: 1.84-3.66), urinary tract infection (UTI) (AOR 5.27, 95% CI: 2.98-9.31), presence of vaginal discharge (AOR 5.33, 95% CI: 3.19-8.92), and malaria (AOR 3.08, 95% CI: 2.32-4.10) were significantly associated with PTB.

CONCLUSIONS

There are many determinants of PTB in East Africa. This review could provide policy makers, clinicians, and program officers to design intervention on preventing occurrence of PTB.

Early malaria infection, dysregulation of angiogenesis, metabolism and inflammation across pregnancy, and risk of preterm birth in Malawi: A cohort study

BACKGROUND

Malaria in pregnancy is associated with adverse birth outcomes. However, the underlying mechanisms remain poorly understood. Tight regulation of angiogenic, metabolic, and inflammatory pathways are essential for healthy pregnancies. We hypothesized that malaria disrupts these pathways leading to preterm birth (PTB).

METHODS AND FINDINGS

We conducted a secondary analysis of a randomized trial of malaria prevention in pregnancy conducted in Malawi from July 21, 2011, to March 18, 2013. We longitudinally assessed circulating mediators of angiogenic, metabolic, and inflammatory pathways during pregnancy in a cohort of HIV-negative women (n = 1,628), with a median age of 21 years [18, 25], and 562 (35%) were primigravid. Pregnancies were ultrasound dated, and samples were analyzed at 13 to 23 weeks (Visit 1), 28 to 33 weeks (Visit 2), and/or 34 to 36 weeks (Visit 3). Malaria prevalence was high; 70% (n = 1,138) had PCR-positive Plasmodium falciparum infection at least once over the course of pregnancy and/or positive placental histology. The risk of delivering preterm in the entire cohort was 20% (n = 304/1506). Women with malaria before 24 weeks gestation had a higher risk of PTB (24% versus 18%, p = 0.005; adjusted relative risk [aRR] 1.30, 95% confidence interval [CI] 1.04-1.63, p = 0.021); and those who were malaria positive only before week 24 had an even greater risk of PTB (28% versus 17%, p = 0.02; with an aRR of 1.67, 95% CI 1.20-2.30, p = 0.002). Using linear mixed-effects modeling, malaria before 24 weeks gestation was associated with altered kinetics of inflammatory (C-Reactive Protein [CRP], Chitinase 3-like protein-1 [CHI3L1], Interleukin 18 Binding Protein [IL-18BP], soluble Tumor Necrosis Factor receptor II [sTNFRII], soluble Intercellular Adhesion Molecule-1 [sICAM-1]), angiogenic (soluble Endoglin [sEng]), and metabolic mediators (Leptin, Angiopoietin-like 3 [Angptl3]) over the course of pregnancy (χ2 > 13.0, p ≤ 0.001 for each). Limitations include being underpowered to assess the impact on nonviable births, being unable to assess women who had not received any antimalarials, and, because of the exposure to antimalarials in the second trimester, there were limited numbers of malaria infections late in pregnancy.

CONCLUSIONS

Current interventions for the prevention of malaria in pregnancy are initiated at the first antenatal visit, usually in the second trimester. In this study, we found that many women are already malaria-infected by their first visit. Malaria infection before 24 weeks gestation was associated with dysregulation of essential regulators of angiogenesis, metabolism, and inflammation and an increased risk of PTB. Preventing malaria earlier in pregnancy may reduce placental dysfunction and thereby improve birth outcomes in malaria-endemic settings.

Maternal and fetal outcome of pregnancy in Swiss mice infected with Plasmodium berghei ANKAGFP

Malaria in pregnant women is associated with risk of maternal and perinatal morbidity and mortality, and there are few antimalarial drugs considered safe to treat them, so it is necessary to develop safer antimalarial medicines. The goal of this study was to develop an animal model for human malaria during pregnancy by characterizing the maternal and fetal outcomes in malaria infected Swiss mice. For that, in the present study, we evaluated the outcome of pregnancy in Swiss mice infected with Plasmodium berghei ANKA^GFP. We observed a reduction of fetal body weight and signs of skeletal ossification retardation in the offspring of mice infected on GD 12. The group of mice infected with malaria presented premature deliveries and histopathology changes consistent with placental malaria. Our study suggests that Swiss Webster mice infected with P. berghei ANKA^GFP on GD 12 might be a valuable model to investigate the safety and the efficacy of new antimalarial drugs indicated to pregnant women.

The prevalence of histologic acute chorioamnionitis among HIV infected pregnant women in Uganda and its association with adverse birth outcomes

BACKGROUND

Preterm birth (PTB) is a leading cause of neonatal mortality and longer-term morbidity. Acute chorioamnionitis (ACA) is a common cause of PTB, however, there are limited data on the prevalence of ACA and its association with PTB in resource limited settings.

METHODS

Data and samples came from a clinical trial evaluating novel strategies for the prevention of malaria in HIV infected pregnant women in Uganda. Women were enrolled between 12-28 weeks of gestation and followed through delivery. For each placenta delivered, three placental tissue types (membrane roll, umbilical cord and chorionic plate/villous parenchyma) were collected. Slides were assessed for diagnosis of maternal and fetal ACA by microscopic evaluation of neutrophilic infiltration using a standardized grading scale. The primary outcomes were PTB (<37 weeks), low birth weight (LBW, <2500 grams), and small-for-gestational age (SGA, birth weight <10th percentile for age). Univariate and multivariate logistic regression were used to estimate associations between 1) maternal characteristics (age, education, wealth, gravidity, gestational age at enrollment, placental malaria, anti-malarial prophylaxis treatment regimen, HIV disease parameters) and ACA, and 2) associations between ACA and adverse birth outcomes.

FINDINGS

A total of 193 placentas were included in the analysis. The prevalence of maternal and fetal ACA was 44.5% and 28.0%, respectively. HIV infected women between 28-43 years of age had a higher risk of maternal ACA compared to those between 17-21 years of age (50.9% vs. 19.1%; aOR = 4.00 (1.10-14.5), p = 0.04) and the diagnosis of severe maternal ACA was associated with a significantly higher risk of PTB (28.6% vs. 6.0%; aOR = 6.04 (1.87-19.5), p = 0.003), LBW (33.3% vs. 9.4%; aOR = 4.86 (1.65-14.3); p = 0.004), and SGA (28.6% vs. 10.1%; aOR = 3.70 (1.20-11.4), p = 0.02). No maternal characteristics were significantly associated with fetal ACA and the diagnosis of fetal ACA was not associated with adverse birth outcomes.

CONCLUSIONS

Histological evidence of severe maternal ACA was associated with an increased risk of PTB, LBW, and SGA in HIV infected, pregnant Ugandan women.

A brief review on features of falciparum malaria during pregnancy

Malaria in pregnancy is a serious public health problem in tropical areas. Frequently, the placenta is infected by accumulation of Plasmodium falciparum-infected erythrocytes in the intervillous space. Falciparum malaria acts during pregnancy by a range of mechanisms, and chronic or repeated infection and co-infections have insidious effects. The susceptibility of pregnant women to malaria is due to both immunological and humoral changes. Until a malaria vaccine becomes available, the deleterious effects of malaria in pregnancy can be avoided by protection against infection and prompt treatment with safe, effective antimalarial agents; however, concurrent infections such as with HIV and helminths during pregnancy are jeopardizing malaria control in sub-Saharan Africa.

Influence of the number and timing of malaria episodes during pregnancy on prematurity and small-for-gestational-age in an area of low transmission

BACKGROUND

Most evidence on the association between malaria in pregnancy and adverse pregnancy outcomes focuses on falciparum malaria detected at birth. We assessed the association between the number and timing of falciparum and vivax malaria episodes during pregnancy on small-for-gestational-age (SGA) and preterm birth.

METHODS

We analysed observational data collected from antenatal clinics on the Thailand-Myanmar border (1986-2015). We assessed the effects of the total number of malaria episodes in pregnancy on SGA and the effects of malaria in pregnancy on SGA, very preterm birth, and late preterm birth, by the gestational age at malaria detection and treatment using logistic regression models with time-dependent malaria variables (monthly intervals). World Health Organisation definitions of very preterm birth (≥28 and <32 weeks) and late preterm birth (≥32 and <37 weeks) and international SGA standards were used.

RESULTS

Of 50,060 pregnant women followed, 8221 (16%) had malaria during their pregnancy. Of the 50,060 newborns, 10,005 (21%) were SGA, 540 (1%) were very preterm, and 4331 (9%) were late preterm. The rates of falciparum and vivax malaria were highest at 6 and 5 weeks' gestation, respectively. The odds of SGA increased linearly by 1.13-fold (95% confidence interval: 1.09, 1.17) and 1.27-fold (1.21, 1.33) per episode of falciparum and vivax malaria, respectively. Falciparum malaria at any gestation period after 12-16 weeks and vivax malaria after 20-24 weeks were associated with SGA (falciparum odds ratio, OR range: 1.15-1.63 [p range: <0.001-0.094]; vivax OR range: 1.12-1.54 [p range: <0.001-0.138]). Falciparum malaria at any gestation period after 24-28 weeks was associated with either very or late preterm birth (OR range: 1.44-2.53; p range: <0.001-0.001). Vivax malaria at 24-28 weeks was associated with very preterm birth (OR: 1.79 [1.11, 2.90]), and vivax malaria at 28-32 weeks was associated with late preterm birth (OR: 1.23 [1.01, 1.50]). Many of these associations held for asymptomatic malaria.

CONCLUSIONS

Protection against malaria should be started as early as possible in pregnancy. Malaria control and elimination efforts in the general population can avert the adverse consequences associated with treated asymptomatic malaria in pregnancy.

Iron Supplementation Alters Heme and Heme Oxygenase 1 (HO-1) Levels In Pregnant Women in Ghana

BACKGROUND

Iron supplementation is recommended for pregnant women to meet their iron requirement for a healthy pregnancy. The benefits and risks of universal iron supplementation during pregnancy in malaria endemic countries are currently being debated. As part of a broader study that focused on the effect of heme/HO-1 on pregnancy outcomes in malaria in pregnancy, we determined the association between iron supplementation and free heme levels in blood of pregnant women with and without malaria in Ghana. We hypothesized that pregnant women with malaria who took iron supplements will have higher levels of Heme/HO-1 than those who did not take iron supplements.

METHODS

A total of 337 women were recruited for this study. Blood samples were collected for malaria diagnosis and heme/HO-1 measurement. Quantification of heme was done using a heme colorimetric assay kit and HO-1 levels were performed using Enzyme-Linked Immunosorbent Assay (ELISA) on plasma samples.

RESULTS

Malaria positive iron supplemented women, in their third trimester, had significantly higher median levels of heme 59.3(43.1 - 60.4) than non-malaria iron supplemented women 35.7(33.0 - 62.2), p = 0.026. Also, malaria positive iron supplemented women had significant higher median levels of HO-16.2(IQR 4.9 - 8.1) than pregnant women who did not take iron supplements 2.9 (IQR 2.1 - 3.8), p = <0.001.

CONCLUSION

Although iron supplementation may be highly beneficial and improve pregnancy outcomes for iron deficient or anemic mothers, it is also likely that iron supplementation for pregnant women who are not iron deficient may put this group of women at risk for adverse pregnancy outcomes. Findings from this study sheds light on the effect of iron supplementation on malaria derived heme in pregnancy, which may inform how iron supplementation is recommended for pregnant women who are not iron deficient.

Prevalence of parasitic infections and associations with pregnancy complications and outcomes in northern Tanzania: a registry-based cross-sectional study

BACKGROUND

Parasitic infection(s) during pregnancy have been associated with increased risk of pregnancy complications and adverse outcomes in low resource settings. However, little is known about their influence on pregnancy outcomes. This study aimed to determine the prevalence of parasitic infections and their association with pregnancy complications and adverse outcomes.

METHODS

A retrospective cross-sectional study was conducted using maternally-linked data from Kilimanjaro Christian Medical Center (KCMC) medical birth registry. Birth records from all women who delivered singleton infants from 2000-2011 were utilized. We excluded multiple gestations and rural medical referral for various medical complications. A total of 30,797 births were evaluated. Data analysis was performed using SPSS version 18.0. Odds ratio (ORs) with 95 % confidence intervals (CIs) for adverse pregnancy outcomes and complications associated with parasitic infections were estimated using multiple logistic regression models. A p-value of less than 5 % was considered statistically significant.

RESULTS

The most prevalent parasitic infection recorded was malaria (17.0 %), while helminths and amebiasis were infrequently recorded (0.6 % vs. 0.7 %, respectively). Women who had malaria during pregnancy had 13 % increased odds of having a preterm delivery (OR = 1.13; 95 % CI: 1.01-1. 26) as compared to those who were not infected. They also had 33 % increased odds of getting maternal anemia (OR = 1.33; 95 % CI: 1.11-1.72). Likewise, pregnant women who were recorded with helminths infections had 29 % increased odds of having maternal anemia as compared to those who had no helminths infection (OR = 1.29; 95 % CI:0.48-3.53). Moreover, pregnant women who were recorded to have amebiasis had 79 % increased odds of having a preterm delivery as compared to those who had no ameba infection (OR = 1.79; 95 % CI: 1.12-2.91).

CONCLUSIONS

Malaria was the prevalent parasitic infection in the studied population while helminth and ameba infections were infrequently reported. These parasitic infections were also associated with increased risk of anemia and delivery of a preterm infant. These were the only three infections/infestations which were evaluated. Our analysis revealed that malaria, helminth and ameba infections during pregnancy is dangerous and has life threatening consequences. This highlight the need to provide early diagnosis and treatment for infected women to prevent pregnancy complications and associated adverse pregnancy outcomes.

Artemether-Lumefantrine Pharmacokinetics and Clinical Response Are Minimally Altered in Pregnant Ugandan Women Treated for Uncomplicated Falciparum Malaria

Artemether-lumefantrine is a first-line regimen for the treatment of uncomplicated malaria during the second and third trimesters of pregnancy. Previous studies have reported changes in the pharmacokinetics and clinical outcomes following treatment with artemether-lumefantrine in pregnant women compared to nonpregnant adults; however, the results are inconclusive. We conducted a study in rural Uganda to compare the pharmacokinetics of artemether-lumefantrine and the treatment responses between 30 pregnant women and 30 nonpregnant adults with uncomplicated Plasmodium falciparum malaria. All participants were uninfected with HIV, treated with a six-dose regimen of artemether-lumefantrine, and monitored clinically for 42 days. The pharmacokinetics of artemether, its metabolite dihydroartemisinin, and lumefantrine were evaluated for 21 days following treatment. We found no significant differences in the overall pharmacokinetics of artemether, dihydroartemisinin, or lumefantrine in a direct comparison of pregnant women to nonpregnant adults, except for a statistically significant but small difference in the terminal elimination half-lives of both dihydroartemisinin and lumefantrine. There were seven PCR-confirmed reinfections (5 pregnant and 2 nonpregnant participants). The observation of a shorter terminal half-life for lumefantrine may have contributed to a higher frequency of reinfection or a shorter posttreatment prophylactic period in pregnant women than in nonpregnant adults. While the comparable overall pharmacokinetic exposure is reassuring, studies are needed to further optimize antimalarial efficacy in pregnant women, particularly in high-transmission settings and because of emerging drug resistance. (This study is registered at ClinicalTrials.gov under registration no. NCT01717885.)

The prevalence of malaria at first antenatal visit in Blantyre, Malawi declined following a universal bed net campaign

Background

Preventing malaria during pregnancy is important for the health of mothers and newborns. Interventions, which include distribution of bed nets and administration of intermittent preventive treatment (IPT), typically occur at the first antenatal visit, usually in the second or third trimester of pregnancy. In 2012, during the course of ongoing clinical studies of malaria among pregnant women in Malawi, a universal bed net campaign was implemented by the Government. This study tested the hypothesis that a universal bed net campaign would decrease the prevalence of malaria among pregnant women at their first antenatal visit.

Methods

Some 1661 women were recruited for two studies from 2009 to 2014. Quantitative PCR (qPCR) was conducted from dried blood spots collected at the first antenatal care visit (prior to administration of IPT or any study interventions) from women who were in their first or second pregnancy and less than 28 weeks gestation by clinical assessment.

Results

Overall, 320 of 1629 (19.6 %) women tested for malaria at their first antenatal visit were infected. Malaria infection rates declined from 28.4 % before the universal bed net campaign, to 18.5 % in 2012, to 15.0 % in the years following the universal bed net campaign. The odds of malaria infection at the time of first antenatal visit in 2012 and the years following the bed net campaign were significantly lower than in the years prior to the intervention (OR 0.6, 95 % CI 0.4–0.8; and OR 0.4, 95 % CI 0.3–0.6, respectively). A similar pattern was observed for the prevalence of clinical malaria. The inverse trend was observed for reported bed net use. However bed net use and malaria infection were not significantly associated on the individual level.

Conclusions

Malaria infection in pregnant women is common even after a bed net campaign in Malawi, though prevalence rates declined. These early infections may cause maternal anaemia and placental malaria resulting in adverse maternal and fetal outcomes. Infection early in pregnancy may also contribute to malaria transmission as pregnant women represent a significant untreated reservoir of parasites. Universal bed net distribution appears to have moderate success in preventing malaria early in pregnancy and these findings support continued efforts to target women early in pregnancy and all women of childbearing age.

Prevalence and predictors of asymptomatic malaria parasitemia among pregnant women in the rural surroundings of Arbaminch Town, South Ethiopia

Background

In Sub-Saharan African countries, including Ethiopia, malaria in pregnancy is a major public health threat which results in significant morbidities and mortalities among pregnant women and their fetuses. In malaria endemic areas, Plasmodium infections tend to remain asymptomatic yet causing significant problems like maternal anemia, low birth weight, premature births, and still birth. This study was conducted to determine the prevalence and predictors of asymptomatic Plasmodium infection among pregnant women in the rural surroundings of Arba Minch Town, Southern Ethiopia.

Methods

A community based cross-sectional study comprising multistage sampling was conducted between April and June, 2013. Socio-demographic data were collected by using a semi-structured questionnaire. Plasmodium infection was diagnosed by using Giemsa-stained blood smear microscopy and a rapid diagnostic test (SD BIOLINE Malaria Ag Pf/Pv POCT, standard diagnostics, inc., Korea).

Results

Of the total 341 pregnant women participated in this study, 9.1% (31/341) and 9.7% (33/341) were confirmed to be infected with Plasmodium species by microscopy and rapid diagnostic tests (RDTs), respectively. The geometric mean of parasite density was 2392 parasites per microliter (μl); 2275/ μl for P. falciparum and 2032/ μl for P. vivax. Parasitemia was more likely to occur in primigravidae (Adjusted odds ratio (AOR): 9.4, 95% confidence interval (CI): 4.3–60.5), secundigravidae (AOR: 6.3, 95% CI: 2.9–27.3), using insecticide treated bed net (ITN) sometimes (AOR: 3.2, 95% CI: 1.8- 57.9), not using ITN at all (AOR: 4.6, 95% CI: 1.4–14.4) compared to multigravidae and using ITN always, respectively.

Conclusion

Asymptomatic malaria in this study is low compared to other studies’ findings. Nevertheless, given the high risk of malaria during pregnancy, pregnant women essentially be screened for asymptomatic Plasmodium infection and be treated promptly via the antenatal care (ANC) services.

Seasonality modifies the effect of a lipid-based nutrient supplement for pregnant rural women on birth length

BACKGROUND

Maternal nutritional status is a major determinant of low birth weight and fluctuates across seasons. Seasonality may influence the outcome of prenatal nutrition interventions that aim to enhance fetal growth.

OBJECTIVE

This study investigated seasonal modifications of the efficacy of a randomized controlled prenatal nutrition intervention trial in pregnant women to improve fetal growth in rural Burkina Faso.

METHODS

The second Micronutriments et Santé de la Mère et de l'Enfant study compared a lipid-based nutrient supplement (LNS) fortified with multiple micronutrients (MMNs) to an MMN supplement. Truncated Fourier series were used to characterize seasonality in birth outcomes. Models that included the Fourier series and newborn and maternal characteristics were used to assess seasonal effect modifications of prenatal supplementation on birth outcomes.

RESULTS

Birth weight, birth length, small for gestational age as a proxy for intrauterine growth retardation, and preterm birth were significantly related to date of birth and showed important seasonal variations. LNSs, which supply energy in addition to MMNs, resulted in a significant increase in birth length (+13.5 mm, 95% CI: 6.5, 20.5 mm) at the transition from rain to dry season (September to November) compared to MMNs alone.

CONCLUSIONS

The climatologic and agricultural seasonal patterns in Burkina Faso affect the efficacy of prenatal LNSs on birth length. In this context, prenatal MMN supplementation programs should be complemented by energy supplementation during the annual rain season to promote fetal growth. This trial was registered at clinicaltrials.gov as NCT00909974.

Pregnant women are a reservoir of malaria transmission in Blantyre, Malawi

Background

During pregnancy, women living in malaria-endemic regions are at increased risk of malaria infection and can harbour chronic placental infections. Intermittent preventive treatment with sulphadoxine-pyrimethamine (SP-IPTp) is administered to reduce malaria morbidity. It was hypothesized that the presence of placental malaria infection and SP-IPTp use would increase the risk of peripheral blood gametocytes, the parasite stage that is transmissible to mosquitoes. This would suggest that pregnant women may be important reservoirs of malaria transmission.

Methods

Light microscopy was used to assess peripheral gametocytaemia in pregnant women enrolled in a longitudinal, observational study in Blantyre, Malawi to determine the association between placental malaria and maternal gametocytaemia. The relationship between SP-IPTp and gametocytaemia was also examined.

Results

2,719 samples from 448 women were analysed and 32 episodes of microscopic gametocytaemia were detected in 27 women. At the time of enrolment 22 of 446 women (4.9%) had gametocytaemia and of the 341 women for whom there was sufficient sampling to analyse infection over the entire course of pregnancy, 27 (7.9%) were gametocytaemic at least once. Gametocytaemia at enrolment was associated with placental malaria, defined as malaria pigment or parasites detected by histology or qPCR, respectively (OR: 32.4, 95% CI: 4.2-250.2), but was not associated with adverse maternal or foetal outcomes. Administration of SP-IPTp did not affect gametocyte clearance or release into peripheral blood.

Conclusions

Gametocytaemia is present in 5% of pregnant women at their first antenatal visit and associated with placental malaria. SP-IPTp does not alter the risk of gametocytaemia. These data suggest that pregnant women are a significant reservoir of gametocyte transmission and should not be overlooked in elimination efforts. Interventions targeting this population would benefit from reaching women prior to first antenatal visit.

Asymptomatic Plasmodium falciparum infection is associated with anaemia in pregnancy and can be more cost-effectively detected by rapid diagnostic test than by microscopy in Kinshasa, Democratic Republic of the Congo

Background

In areas of high malaria transmission, Plasmodium falciparum infection during pregnancy is characterized by malaria-related anaemia, placental malaria and does not always result in clinical symptoms. This situation is associated with poor pregnancy outcomes. The aim of this study was to determine the extent of asymptomatic P. falciparum infection, its relation with anaemia as well as the most cost-effective technique for its diagnosis in healthy pregnant women living in Kinshasa, Democratic Republic of the Congo.

Methods

In a cross-sectional study design, information on socio-demographic characteristics and cost data were collected in healthy pregnant women attending antenatal care consultations. Plasmodium falciparum infection was diagnosed using rapid diagnostic test (RDT), microscopy and polymerase chain reaction (PCR). Haemoglobin concentration was also determined.

Results

In total, 332 pregnant women were enrolled. RDT and microscopy data were available for all the blood samples and 166 samples were analysed by PCR. The prevalence of asymptomatic P. falciparum infection using microscopy, RDTs and PCR, were respectively 21.6%, 27.4% and 29.5%. Taking PCR as a reference, RDTs had a sensitivity of 81.6% and a specificity of 94.9% to diagnose asymptomatic P. falciparum infection. The corresponding values for microscopy were 67.3% and 97.4%. The prevalence of anaemia was 61.1% and asymptomatic malaria increased five times the odds (p < 0.001) of having anaemia. RDTs were more cost-effective compared to microscopy. Incremental cost-effectiveness ratio was US$ 63.47 per microscopy adequately diagnosed case.

Conclusion

These alarming results emphasize the need to actively diagnose and treat asymptomatic malaria infection during all antenatal care visits. Moreover, in DRC, malaria and anaemia control efforts should be strengthened by promoting the use of insecticide-treated nets, intermittent preventive treatment with sulphadoxine-pyrimethamine and iron and folic acid supplements.

A model of parity-dependent immunity to placental malaria

Plasmodium falciparum placental infection during pregnancy is harmful for both mother and child. Protection from placental infection is parity-dependent, that is, acquired over consecutive pregnancies. However, the infection status of the placenta can only be assessed at delivery. Here, to better understand the mechanism underlying this parity-dependence, we fitted a model linking malaria dynamics within the general population to observed placental histology. Our results suggest that immunity resulting in less prolonged infection is a greater determinant of the parity-specific patterns than immunity that prevents placental sequestration. Our results also suggest the time when maternal blood first flows into the placenta is a high-risk period. Therefore, preventative strategies implementable before or early in pregnancy, such as insecticide-treated net usage in women of child-bearing age or any future vaccine, could substantially reduce the number of women who experience placental infection.

Malaria and fetal growth alterations in the 3(rd) trimester of pregnancy: a longitudinal ultrasound study

Background

Pregnancy associated malaria is associated with decreased birth weight, but in-utero evaluation of fetal growth alterations is rarely performed. The objective of this study was to investigate malaria induced changes in fetal growth during the 3^rd trimester using trans-abdominal ultrasound.

Methods

An observational study of 876 pregnant women (398 primi- and secundigravidae and 478 multigravidae) was conducted in Tanzania. Fetal growth was monitored with ultrasound and screening for malaria was performed regularly. Birth weight and fetal weight were converted to z-scores, and fetal growth evaluated as fetal weight gain from the 26th week of pregnancy.

Results

Malaria infection only affected birth weight and fetal growth among primi- and secundigravid women. Forty-eight of the 398 primi- and secundigravid women had malaria during pregnancy causing a reduction in the newborns z-score of −0.50 (95% CI: −0.86, −0.13, P = 0.008, multiple linear regression). Fifty-eight percent (28/48) of the primi- and secundigravidae had malaria in the first half of pregnancy, but an effect on fetal growth was observed in the 3^rd trimester with an OR of 4.89 for the fetal growth rate belonging to the lowest 25% in the population (95%CI: 2.03–11.79, P<0.001, multiple logistic regression). At an individual level, among the primi- and secundigravidae, 27% experienced alterations of fetal growth immediately after exposure but only for a short interval, 27% only late in pregnancy, 16.2% persistently from exposure until the end of pregnancy, and 29.7% had no alterations of fetal growth.

Conclusions

The effect of malaria infections was observed during the 3^rd trimester, despite infections occurring much earlier in pregnancy, and different mechanisms might operate leading to different patterns of growth alterations. This study highlights the need for protection against malaria throughout pregnancy and the recognition that observed changes in fetal growth might be a consequence of an infection much earlier in pregnancy.

Rescreening for abnormal vaginal flora in pregnancy and re-treating with clindamycin vaginal cream significantly increases cure and improvement rates

We investigated 199 pregnant women with bacterial vaginosis (BV) who received clindamycin vaginal cream (CVC) for three days and compared with 205 women treated with placebo. The vaginal flora was assessed at each visit. At the second visit, 71% in the CVC group were cured/improved, compared with 12% in the placebo group (P < 0.001). At visit 3 about 90% who responded to initial CVC treatment were still cured/improved. Of women who initially failed to respond to CVC and were given an additional seven-day course, 33% were cured/improved by the third visit, compared with 15% who failed to respond to placebo initially and were given a further seven-day course (P = 0.02). By visit 4, half the women in the CVC group who received additional treatment remained cured/improved, compared with 26% who had additional placebo (P = 0.004). In the CVC group, a change from abnormal to normal rose from 71% (visit 2) to 76% (visit 3) and 79% (visit 4). A similar trend was seen in women who received placebo but the proportions were significantly lower (12%, 24% and 33%, respectively). There is value in rescreening and re-treating women who remain BV-positive after initial clindamycin treatment.

Placental malaria and the relationship to pregnancy outcome at Gushegu District Hospital, Northern Ghana

One complication of malaria infection during pregnancy is the sequestration of parasites in the placenta. The aim of this study was to determine the association between placental malaria and pregnancy outcome. This study was conducted at the Gushegu District Hospital in Ghana from June to August 2010. Sulfadoxine-pyrimethamine (SP) was used as intermittent preventative treatment (IPT) during pregnancy. All mothers reporting for delivery were enrolled, except in cases of multiple pregnancies. The data was documented using a questionnaire. A placental blood sample was collected and analysed for malaria parasites. There were 56/107(52%) malaria positive samples. In women with placental malaria perinatal mortality was higher, duration of pregnancy shorter and birth weight lower. These results were statistically significant. In primigravidae the negative effects were more obvious. IPT is extensively implemented in Ghana, but this study found no evidence for an association between the number of doses and the outcome of pregnancy.

The roles of the immune system in women's reproduction: evolutionary constraints and life history trade-offs

Life history theory posits that, as long as survival is assured, finite resources are available for reproduction, maintenance, and growth/storage. To maximize lifetime reproductive success, resources are subject to trade-offs both within individuals and between current and future investment. For women, reproducing is costly and time-consuming; the bulk of available resources must be allocated to reproduction at the expense of more flexible systems like immune function. When reproducing women contract infectious diseases, the resources required for immune activation can fundamentally shift the patterns of resource allocation. Adding to the complexity of the reproductive-immune trade-offs in women are the pleiotropic effects of many immune factors, which were modified to serve key roles in mammalian reproduction. In this review, we explore the complex intersections between immune function and female reproduction to situate proximate immunological processes within a life history framework. After a brief overview of the immune system, we discuss some important physiological roles of immune factors in women's reproduction and the conflicts that may arise when these factors must play dual roles. We then discuss the influence of reproductive-immune trade-offs on the patterning of lifetime reproductive success: (1) the effect of immune activation/infectious disease on the timing of life history events; (2) the role of the immune system, immune activation, and infectious disease on resource allocation within individual reproductive events, particularly pregnancy; and (3) the role of the immune system in shaping the offspring's patterns of future life history trade-offs. We close with a discussion of future directions in reproductive immunology for anthropologists.

Moderate to severe, but not mild, maternal anemia is associated with increased risk of small-for-gestational-age outcomes

Anemia is highly prevalent globally, estimated at 40-50% in women of reproductive age. Prior studies have produced inconclusive evidence as to the association between maternal anemia and intrauterine growth restriction (IUGR). We conducted a systematic review of the literature containing associations between maternal anemia and small for gestational age (SGA) outcomes (as a proxy for IUGR). A meta-analysis was performed to pool associations, categorized by the hemoglobin cutoffs presented by the authors. We identified 12 studies reporting associations between maternal anemia and SGA. For the meta-analysis, there were 7 associations with a hemoglobin cutoff <110 g/L, 7 with a cutoff <100 g/L, and 5 with a cutoff <90 or <80 g/L. Although the <110- and <100-g/L categories showed no significant relationship with SGA, the <90- or <80-g/L category was associated with a 53% increase in risk of the newborn being SGA [pooled OR = 1.53 (95% CI: 1.24-1.87); P < 0.001]. Moderate to severe, but not mild, maternal anemia appears to have an association with SGA outcomes, but the findings must be viewed with caution due to the great heterogeneity of the studies. Further examination should be conducted using datasets with better standardized definitions and measurements of exposure and outcome.

Prospects and Pitfalls of Pregnancy-Associated Malaria Vaccination Based on the Natural Immune Response to Plasmodium falciparum VAR2CSA-Expressing Parasites

Pregnancy-associated malaria, a manifestation of severe malaria, is the cause of up to 200,000 infant deaths a year, through the effects of placental insufficiency leading to growth restriction and preterm delivery. Development of a vaccine is one strategy for control. Plasmodium falciparum-infected red blood cells accumulate in the placenta through specific binding of pregnancy-associated parasite variants that express the VAR2CSA antigen to chondroitin sulphate A on the surface of syncytiotrophoblast cells. Parasite accumulation, accompanied by an inflammatory infiltrate, disrupts the cytokine balance of pregnancy with the potential to cause placental damage and compromise foetal growth. Multigravid women develop immunity towards VAR2CSA-expressing parasites in a gravidity-dependent manner which prevents unfavourable pregnancy outcomes. Although current vaccine design, targeting VAR2CSA antigens, has succeeded in inducing antibodies artificially, this candidate may not provide protection during the first trimester and may only protect those women living in areas endemic for malaria. It is concluded that while insufficient information about placental-parasite interactions is presently available to produce an effective vaccine, incremental progress is being made towards achieving this goal.

Placental malaria is associated with attenuated CD4 T-cell responses to tuberculin PPD 12 months after BCG vaccination

BACKGROUND

Placental malaria (PM) is associated with prenatal malaise, but many PM+ infants are born without symptoms. As malaria has powerful immunomodulatory effects, we tested the hypothesis that PM predicts reduced T-cell responses to vaccine challenge.

METHODS

We recruited healthy PM+ and PM- infants at birth. At six and 12 months, we stimulated PBMCs with tuberculin purified protein derivative (PPD) and compared expression of CD154, IL-2 and IFNγ by CD4 T-cells to a negative control using flow cytometry.We measured the length, weight and head circumference at birth and 12 months.

RESULTS

IL-2 and CD154 expression were low in both groups at both timepoints, without discernable differences. Expression of IFNγ was similarly low at 6 months but by 12 months, the median response was higher in PM- than PM + infants (p = 0.026). The PM+ infants also had a lower weight (p = 0.032) and head circumference (p = 0.041) at 12 months, indicating lower growth rates.At birth, the size and weight of the PM+ and PM- infants were equivalent. By 12 months, the PM+ infants had a lower weight and head circumference than the PM- infants.

CONCLUSIONS

Placental malaria was associated with reduced immune responses 12 months after immune challenge in infants apparently healthy at birth.

The effectiveness and perception of the use of sulphadoxine-pyrimethamine in intermittent preventive treatment of malaria in pregnancy programme in Offinso district of Ashanti region, Ghana

Background

Malaria in pregnant women has been shown to be associated with low birth weight, stillbirth and mortality in newborns. The WHO has adopted the use of sulphadoxine-pyrimethamine (SP) to control malaria, a disease which worsens the plight of pregnant women leading to low birth weight, stillbirths and increased neonatal mortality. The present study assessed the effectiveness of SP and perception of its use in pregnant women in Offinso district (Ashanti Region), Ghana.

Method

Pregnant women, gestational age 32 weeks prior to term, were studied from November 2006 to October 2007. Their haemoglobin levels (Hb), parasitaemia and other quantitative determinants were assessed. In-depth interviews (IDIs) and focus group discussions (FGDs) were used to assess the perception of SP usage and its effectiveness.

Results

Of the 306 study participants, 92 (30%) took one dose, 100 (33%) two doses and 114 (37%) three doses of SP, respectively. There was significant association between gravidity and SP dosage taken (Pearson χ² = 18.9, p < 0.001). Although adverse effects were produced in 113 (i.e. 37%) of the pregnant women, no significant difference was observed with regard to the dosage of SP taken (Pearson's χ² = 2.3, p ≥ 0.32). Peripheral parasitaemia was present in 47 (15%) of the subjects. There was a poor negative relationship of doses of SP with parasitaemia (r = -0.07, p ≥ 0.24). Mean Hb was 11.3 ± 1.6 g/dl, with 118 (39%) of the subjects anaemic (Hb < 11.0 g/dl), whilst 187 (61%) were normal (Hb ≥11.0 g/dl). Significant positive correlation of SP use with Hb level (r = 0.15, p < 0.008) was observed. SP use reduced malaria and anaemia prevalence, contributed to reduced maternal morbidity with mild side effects being reported.

Conclusions

This study points to the effectiveness of IPTp using SP as an evidence-based measure for control of malaria and malaria-related anaemia in pregnancy. Therefore, the Ghana Health Service should improve current programme strategies to increase the proportion of pregnant women who take three doses of SP, paying attention to improved face-to-face health education, focussed antenatal care and better social mobilization.

Nutritional status of Makushi Amerindian children and adolescents of Guyana

BACKGROUND

Amazonian Indians are in the midst of a rapid cultural transition. The developments affecting Amazonian Indians present an opportunity to address important public health problems through public and private initiatives, but to do so it is imperative to begin with information on the health status of these peoples and the underlying factors affecting it. However, relatively few such data are available for this vast region.

AIM

This study describes the nutritional status of Makushi Amerindians of Guyana and considers several variables which might help to explain it.

SUBJECTS AND METHODS

Data for 792 Makushi, 0-20 years of age from 11 villages are considered. Outcome variables considered are anthropometric markers of growth and nutritional status; specifically height-for-age, weight-for-height and body-mass index. Predictor variables explored are age, sex, relative isolation, number of siblings, season of birth, diet and morbidity. Fisher's exact test, chi-square, Pearson's correlation and multiple regression were used to assess possible relationships between these variables.

RESULTS

Relative to other Amazonian Indians, the Makushi have a lower rate of linear-growth faltering and a higher rate of linear-growth faltering relative to non-Amerindian Guyanese. Males, older cohorts, those living in isolated villages or born in the wet season showed higher rates of growth faltering.

CONCLUSION

Makushi nutritional status may be explained by sex, age, relative isolation, family size, season of birth, dietary intake and infectious disease.

Coverage of intermittent prevention treatment with sulphadoxine-pyrimethamine among pregnant women and congenital malaria in Côte d'Ivoire

Background

The World Health Organization (WHO) recommends using insecticide-treated mosquito nets (ITNs) and intermittent preventive treatment with sulphadoxine-pyrimethamine (IPT-SP) to prevent malaria in sub-Saharan Africa. Data on IPT-SP coverage and factors associated with placental malaria parasitaemia and low birth weight (LBW) are scarce in Côte d'Ivoire.

Methods

A multicentre, cross-sectional survey was conducted in Côte d'Ivoire from March to September 2008 at six urban and semi-urban antenatal clinics. Standardized forms were used to collect the demographic information and medical histories of women and their offspring. IPT-SP coverage (≥2 doses) as well as placental and congenital malaria prevalence parasitaemia were estimated. Regression logistics were used to study factors associated with placental malaria and LBW (birth weight of alive babies < 2,500 grams).

Results

Overall, 2,044 women with a median age of 24 years were included in this study. Among them 1017 (49.8%) received ≥2 doses of IPT-SP and 694 (34.0%) received one dose. A total of 99 mothers (4.8%) had placental malaria, and of them, four cases of congenital malaria were diagnosed. Factors that protected from maternal placental malaria parasitaemia were the use of one dose (adjusted odds ratio (aOR), 0.32; 95%CI: 0.19-0.55) or ≥2 doses IPT-SP (aOR: 0.18; 95%CI: 0.10-0.32); the use of ITNs (aOR: 0.47; 95%CI: 0.27-0.82). LBW was associated with primigravidity and placental malaria parasitaemia.

Conclusion

IPT-SP decreases the rate of placental malaria parasitaemia and has a strong dose effect. Despite relatively successful IPT-SP coverage in Côte d'Ivoire, substantial commitments from national authorities are urgently required for such public health campaigns. Strategies, such as providing IPT-SP free of charge and directly observing treatment, should be implemented to increase the use of IPT-SP as well as other prophylactic methods.

Effect of repeated treatment of pregnant women with sulfadoxine-pyrimethamine and azithromycin on preterm delivery in Malawi: a randomized controlled trial

Preterm delivery, which is associated with infections during pregnancy, is common in sub-Saharan Africa. We enrolled 1,320 pregnant women into a randomized, controlled trial in Malawi to study whether preterm delivery and low birth weight (LBW) incidence can be reduced by intermittent preventive treatment of maternal malaria and reproductive tract infections. The participants received either sulfadoxine-pyrimethamine (SP) twice (controls), monthly SP, or monthly SP and two doses of azithromycin (AZI-SP). The incidence of preterm delivery was 17.9% in controls, 15.4% in the monthly SP group (P = 0.32), and 11.8% in AZI-SP group (risk ratio = 0.66, P = 0.01). Compared with controls, those in AZI-SP group had a risk ratio of 0.61 (P = 0.02) for LBW. Incidence of serious adverse events was low in all groups. In conclusion, the incidence of preterm delivery and LBW can in some conditions be reduced by treating pregnant women with monthly SP and two azithromycin doses.

Comparison of real-time PCR and microscopy for malaria parasite detection in Malawian pregnant women

BACKGROUND

New diagnostic tools for malaria are required owing to the changing epidemiology of malaria, particularly among pregnant women in sub-Saharan Africa. Real-time PCR assays targeting Plasmodium falciparum lactate dehydrogenase (pfldh) gene may facilitate the identification of a high proportion of pregnant women with a P. falciparum parasitaemia below the threshold of microscopy. These molecular methods will enable further studies on the effects of these submicroscopic infections on maternal health and birth outcomes.

METHODS

The pfldh real-time PCR assay and conventional microscopy were compared for the detection of P. falciparum from dried blood spots and blood smears collected from the peripheral blood of 475 Malawian women at delivery. A cycle threshold (Ct) of the real-time PCR was determined optimizing the sensitivity and specificity of the pfldh PCR assay compared to microscopy. A real-time PCR species-specific assay was applied to identify the contribution to malaria infections of three Plasmodium species (P. falciparum P. ovale and P. malariae) in 44 discordant smear and pfldh PCR assay results.

RESULTS

Of the 475 women, P. falciparum was detected in 11 (2.3%) by microscopy and in 51 (10.7%) by real-time PCR; compared to microscopy, the sensitivity of real-time PCR was 90.9% and the specificity 91.2%. If a Ct value of 38 was used as a cut-off, specificity improved to 94.6% with no change in sensitivity. The real-time PCR species-specific assay detected P. falciparum alone in all but four samples: two samples were mixed infections with P. falciparum and P. malariae, one was a pure P. malariae infection and one was a pfldh PCR assay-positive/species-specific assay-negative sample. Of three P. malariae infections detected by microscopy, only one was confirmed by the species-specific assay.

CONCLUSIONS

Although microscopy remains the most appropriate method for clinical malaria diagnosis in field settings, molecular diagnostics such as real-time PCR offer a more reliable means to detect malaria parasites, particularly at low levels. Determination of the possible contribution of these submicroscopic infections to poor birth outcomes and maternal health is critical. For future studies to investigate these effects, this pfldh real-time PCR assay offers a reliable detection method.

Infectious disease and reproductive health: a review

Human reproduction provides unique opportunities for the transmission of infectious agents. Furthermore, the mother and her offspring have distinct susceptibilities to infection at each stage of reproduction, from conception and gestation to parturition and the neonatal period. The impact of pathogens on reproduction can be mitigated or exacerbated depending on timing of acquisition during pregnancy. Similarly, factors such as maternal immune response, nutritional status, or concurrent infection may modify the effect of an infectious agent. In this review, we discuss the evidence--or lack thereof--for associations between infectious agents and reproductive problems at each stage of reproduction. We focus on well-substantiated associations, and consider several emerging or controversial associations. We discuss the challenges, limitations, and opportunities related to epidemiologic research on infectious disease and reproductive outcomes.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader will be able to describe the potential mechanisms by which infectious agents may impact productive health, explain the public health impact of infectious diseases on reproductive health, and summarize the perinatal risks of infectious disease and relate this to treatment and prevention strategies in practice.

The effect of timing and frequency of Plasmodium falciparum infection during pregnancy on the risk of low birth weight and maternal anemia

Plasmodium falciparum infection during pregnancy causes maternal anemia and low birth weight (LBW), but the effect of frequency and timing of infection on the severity of these adverse effects is unknown. We conducted a cohort study recruiting 2462 pregnant women in Malawi. Microscopy was used to diagnose malaria at enrollment, follow-up and delivery. Birth weight and maternal hemoglobin were measured at delivery. The association between timing and frequency of infection and LBW and maternal anemia was analyzed using a binomial regression model. Compared with uninfected women, (i) the risk of LBW increased with the number of malaria episodes [one episode: prevalence ratio (PR) 1.62 (95% CI 1.07-2.46); two episodes: PR 2.41 (95% CI 1.39-4.18)]; (ii) the risk for maternal anemia increased with the number of malaria episodes [one episode: PR 1.15 (95% CI 0.86-1.54); two episodes: PR 1.82 (95% CI 1.28-2.62)]; and (iii) the risk of LBW was higher with infection in the second (PR 1.71; 95% CI 1.06-2.74) than third trimester or at delivery (PR 1.55; 95% CI 0.88-2.75). The timing and frequency of P. falciparum infection during pregnancy affected the risk of LBW but only frequency of infection had an effect on the risk of maternal anemia. Identification of gestational periods when malaria causes most adverse outcomes will facilitate effective targeting of interventions.

Dysregulation of angiopoietins is associated with placental malaria and low birth weight

Background

Placental malaria (PM) is associated with adverse pregnancy outcomes including low birth weight (LBW). However, the precise mechanisms by which PM induces LBW are poorly defined. Based on the essential role of angiopoietin (ANG)-1 and -2 in normal placental vascular development, we hypothesized that PM may result in the dysregulation of angiopoietins and thereby contribute to LBW outcomes.

Methods and Findings

In a mouse model of PM, we show that Plasmodium berghei ANKA infection of pregnant mice resulted in dysregulated angiopoietin levels and fetal growth restriction. PM lead to decreased ANG-1, increased ANG-2, and an elevated ratio of ANG-2/ANG-1 in the placenta and the serum. These observations were extended to malaria-exposed pregnant women: In a study of primigravid women prospectively followed over the course of pregnancy, Plasmodium falciparum infection was associated with a decrease in maternal plasma ANG-1 levels (P = 0.031) and an increase in the ANG-2:ANG-1 ratio (P = 0.048). ANG-1 levels recovered with successful treatment of peripheral parasitemia (P = 0.010). In a cross-sectional study of primigravidae at delivery, angiopoietin dysregulation was associated with PM (P = 0.002) and LBW (P = 0.041). Women with PM who delivered LBW infants had increased ANG-2:ANG-1 ratios (P = 0.002) compared to uninfected women delivering normal birth weight infants.

Conclusions

These data support the hypothesis that dysregulation of angiopoietins is associated with PM and LBW outcomes, and suggest that ANG-1 and ANG-2 levels may be clinically informative biomarkers to identify P. falciparum-infected mothers at risk of LBW deliveries.

Global report on preterm birth and stillbirth (2 of 7): discovery science

Background

Normal and abnormal processes of pregnancy and childbirth are poorly understood. This second article in a global report explains what is known about the etiologies of preterm births and stillbirths and identifies critical gaps in knowledge. Two important concepts emerge: the continuum of pregnancy, beginning at implantation and ending with uterine involution following birth; and the multifactorial etiologies of preterm birth and stillbirth. Improved tools and data will enable discovery scientists to identify causal pathways and cost-effective interventions.

Pregnancy and parturition continuum

The biological process of pregnancy and childbirth begins with implantation and, after birth, ends with the return of the uterus to its previous state. The majority of pregnancy is characterized by rapid uterine and fetal growth without contractions. Yet most research has addressed only uterine stimulation (labor) that accounts for <0.5% of pregnancy.

Etiologies

The etiologies of preterm birth and stillbirth differ by gestational age, genetics, and environmental factors. Approximately 30% of all preterm births are indicated for either maternal or fetal complications, such as maternal illness or fetal growth restriction. Commonly recognized pathways leading to preterm birth occur most often during the gestational ages indicated: (1) inflammation caused by infection (22-32 weeks); (2) decidual hemorrhage caused by uteroplacental thrombosis (early or late preterm birth); (3) stress (32-36 weeks); and (4) uterine overdistention, often caused by multiple fetuses (32-36 weeks). Other contributors include cervical insufficiency, smoking, and systemic infections. Many stillbirths have similar causes and mechanisms. About two-thirds of late fetal deaths occur during the antepartum period; the other third occur during childbirth. Intrapartum asphyxia is a leading cause of stillbirths in low- and middle-income countries.

Recommendations

Utilizing new systems biology tools, opportunities now exist for researchers to investigate various pathways important to normal and abnormal pregnancies. Improved access to quality data and biological specimens are critical to advancing discovery science. Phenotypes, standardized definitions, and uniform criteria for assessing preterm birth and stillbirth outcomes are other immediate research needs.

Conclusion

Preterm birth and stillbirth have multifactorial etiologies. More resources must be directed toward accelerating our understanding of these complex processes, and identifying upstream and cost-effective solutions that will improve these pregnancy outcomes.

The effect of malaria and intestinal helminth coinfection on birth outcomes in Kumasi, Ghana

This study was conducted to investigate the effect of Plasmodium falciparum and intestinal helminth coinfection on maternal anemia and birth outcomes. A cross-sectional study of 746 women who delivered in two hospitals in Kumasi was conducted. Data were collected using an investigator-administered questionnaire and from patients' medical records. Blood was collected for determination of P. falciparum and hemoglobin levels. Adverse pregnancy outcomes were high (44.6%). Coinfection (versus no infection) was associated with 3-fold increase in low birth weight. For women with anemia, coinfection was 2.6 times and 3.5 times as likely to result in preterm deliveries and small for gestational age infants. The odds of having anemia was increased almost 3-fold by coinfection. Coinfection (versus helminth only) resulted in increased risks of anemia, low birth weight, and small for gestational age infants. This study demonstrates that women with malaria and intestinal helminth coinfection are at particular risk of adverse birth outcomes.

Malaria during pregnancy in endemic areas: a lens for examining maternal-fetal conflict

Most of our knowledge about maternal-fetal conflict derives from the battle over scarce nutritional resources. How do other stressors like infectious diseases alter the maternal-fetal relationship? In this article, we use the example of malaria infection during pregnancy to explore the altered maternal-fetal relationship in the presence of an infectious disease. While adults living in regions endemic to Plasmodium falciparum malaria are generally immune, pregnant women experience significantly more frequent and severe infections. These infections generally resolve within a few days of birth and rarely cross the placenta, but the infants often experience poor birth outcomes, particularly low birth weight. This article summarizes what is known about the proximate, or physiological, mechanisms by which malaria causes more severe or frequent infections for pregnant versus nonpregnant women in endemic regions and then utilizes an evolutionary approach to focus on the altered maternal-fetal relationship during malaria-infected pregnancy.

Impact of maternal malaria and under-nutrition on intrauterine growth restriction: a prospective ultrasound study in Democratic Republic of Congo

Maternal malaria and under-nutrition are established risk factors for small-for-gestational-age (SGA) births; however, whether malaria is associated with intrauterine growth restriction (IUGR) is unknown. We investigated IUGR risk among 177 HIV-negative pregnant women enrolled in a longitudinal ultrasound study conducted in Democratic Republic of Congo from May 2005 to May 2006. Malaria infection, maternal anthropometrics, and ultrasound estimated fetal weight were measured monthly. All positive malaria cases were treated and intermittent presumptive therapy (IPTp) provided. Log-binomial regression models for IUGR were fitted using generalized estimating equations to account for statistical clustering of repeat IUGR measurements. Twenty-nine percent of fetuses experienced an episode of IUGR with the majority occurring in the third trimester. The risk of IUGR associated with malaria was greatest after three or more cumulative infections (RR 3·3, 95% CI 1·3–8·2) and was two- to eight-fold higher among women with evidence of under-nutrition. Receiving antimalarial treatment in the previous month (for IPTp or treatment) was significantly protective against IUGR (RR 0·5, 95% CI 0·3–0·7). The interaction observed between malaria and under-nutrition suggests that antenatal programmes in malaria endemic areas should incorporate nutritional screening and supplementation in addition to IPTp.

Adverse pregnancy outcomes in an area where multidrug-resistant plasmodium vivax and Plasmodium falciparum infections are endemic

BACKGROUND

Plasmodium falciparum infection exerts a considerable burden on pregnant women, but less is known about the adverse consequences of Plasmodium vivax infection.

METHODS

In Papua, Indonesia, where multiple drug resistance to both species has emerged, we conducted a cross-sectional hospital-based study to quantify the risks and consequences of maternal malaria.

RESULTS

From April 2004 through December 2006, 3046 pregnant women were enrolled in the study. The prevalence of parasitemia at delivery was 16.8% (432 of 2570 women had infections), with 152 (35.2%) of these 432 infections being associated with fever. The majority of infections were attributable to P. falciparum (250 [57.9%]); 146 (33.8%) of the infections were attributable to P. vivax, and 36 (8.3%) were coinfections with both species. At delivery, P. falciparum infection was associated with severe anemia (hemoglobin concentration, <7 g/dL; odds ratio [OR], 2.8; 95% confidence interval [95% CI], 2.0-4.0) and a 192 g (95% CI, 119-265) reduction in mean birth weight (P<.001). P. vivax infection was associated with an increased risk of moderate anemia (hemoglobin concentration, 7-11 g/dL; OR, 1.8; 95% CI, 1.2-2.9; P=.01) and a 108 g (95% CI, 17.5-199) reduction in mean birth weight (P<.019). Parasitemia was associated with preterm delivery (OR, 1.5; 95% CI, 1.1-2.0; P=.02) and stillbirth (OR, 2.3; 95% CI, 1.3-4.1; P=.007) but was not associated with these outcomes after controlling for the presence of fever and severe anemia, suggesting that malaria increases the risk of preterm delivery and stillbirth through fever and contribution to severe anemia rather than through parasitemia per se.

CONCLUSIONS

These observations highlight the need for novel, safe, and effective treatment and prevention strategies against both multidrug-resistant P. falciparum and multidrug-resistant P. vivax infections in pregnant women in areas of mixed endemicity.

An evaluation of the use of reported febrile illness in predicting malaria in pregnancy

The object of this study was to evaluate the sensitivity and specificity of reported febrile illness in predicting malaria in pregnant women at booking in NAUTH, Nnewi. This was a case control prospective survey using a structured questionnaire to collect data from pregnant women attending antenatal clinic of Nnamdi Azikiwe University Teaching Hospital between April and September 2001. Peripheral blood smears were examined in 420 pregnant women during their first antenatal visit. This study showed that 57.4% of parasitaemic pregnant women and 54% of aparasitaemic pregnant women reported fever before their first antenatal visit. The sensitivity and specificity of reported febrile illness in predicting malaria were 57.4% and 46%, respectively. However, the predictive value of a positive test was as high as 80.25%, while it was only 22% for the predictive value of a negative test. The efficiency of reported febrile illness as a screening device was 55%. Reliance on reported febrile illness will not be adequate to identify parasitaemic pregnant women because many of those with heavy placental parasitisation may not report fever. This justifies the place of the intermittent presumptive therapy using sulphadoxine-pyrimethamine in pregnant women living in malaria endemic areas such as sub-Saharan Africa.

Pregnancy outcome and placenta pathology in Plasmodium berghei ANKA infected mice reproduce the pathogenesis of severe malaria in pregnant women

Pregnancy-associated malaria (PAM) is expressed in a range of clinical complications that include increased disease severity in pregnant women, decreased fetal viability, intra-uterine growth retardation, low birth weight and infant mortality. The physiopathology of malaria in pregnancy is difficult to scrutinize and attempts were made in the past to use animal models for pregnancy malaria studies. Here, we describe a comprehensive mouse experimental model that recapitulates many of the pathological and clinical features typical of human severe malaria in pregnancy. We used P. berghei ANKA-GFP infection during pregnancy to evoke a prominent inflammatory response in the placenta that entails CD11b mononuclear infiltration, up-regulation of MIP-1 alpha chemokine and is associated with marked reduction of placental vascular spaces. Placenta pathology was associated with decreased fetal viability, intra-uterine growth retardation, gross post-natal growth impairment and increased disease severity in pregnant females. Moreover, we provide evidence that CSA and HA, known to mediate P. falciparum adhesion to human placenta, are also involved in mouse placental malaria infection. We propose that reduction of maternal blood flow in the placenta is a key pathogenic factor in murine pregnancy malaria and we hypothesize that exacerbated innate inflammatory responses to Plasmodium infected red blood cells trigger severe placenta pathology. This experimental model provides an opportunity to identify cell and molecular components of severe PAM pathogenesis and to investigate the inflammatory response that leads to the observed fetal and placental blood circulation abnormalities.