Calcium supplementation during pregnancy for preventing hypertensive disorders and related problems

Renal calcium and magnesium handling during pregnancy: modeling and analysis

Pregnancy is associated with elevated demand of most nutrients, with many trace elements and minerals critical for the development of fetus. In particular, calcium (Ca2+) and magnesium (Mg2+) are essential for cellular function, and their deficiency can lead to impaired fetal growth. A key contributor to the homeostasis of these ions is the kidney, which in a pregnant rat undergoes major changes in morphology, hemodynamics, and molecular structure. The goal of this study is to unravel the functional implications of these pregnancy-induced changes in renal handling of Ca2+ and Mg2+, two cations that are essential in a healthy pregnancy. To achieve that goal, we developed computational models of electrolyte and water transport along the nephrons of a rat in mid and late pregnancy. Model simulations reveal a substantial increase in the reabsorption of Mg2+ along the proximal tubules and thick ascending limbs. In contrast, the reabsorption of Ca2+ is increased in the proximal tubules but decreased in the thick ascending limbs, due to the lower transepithelial concentration gradient of Ca2+ along the latter. Despite the enhanced transport capacity, the marked increase in glomerular filtration rate results in elevated urinary excretions of Ca2+ and Mg2+ in pregnancy. Furthermore, we conducted simulations of hypocalcemia and hypomagnesemia. We found that hypocalcemia lowers Ca2+ excretion substantially more than Mg2+ excretion, with this effect being more pronounced in virgin rats than in pregnant ones. Conversely, hypomagnesemia reduces the excretion of Mg2+ and Ca2+ to more similar degrees. These differences can be explained by the greater sensitivity of the calcium-sensing receptor (CaSR) to Ca2+ compared with Mg2+.NEW & NOTEWORTHY A growing fetus' demands of minerals, notably calcium and magnesium, necessitate adaptations in pregnancy. In particular, the kidney undergoes major changes in morphology, hemodynamics, and molecular structure. This computational modeling study provides insights into how these pregnancy-induced renal adaptation impact calcium and magnesium transport along different nephron segments. Model simulations indicate that, despite the enhanced transport capacity, the marked increase in glomerular filtration rate results in elevated urinary excretions of calcium and magnesium in pregnancy.

Impact of helminth infections during pregnancy on maternal and newborn Vitamin D and on birth outcomes

Poor birth outcomes in low- and middle income countries are associated with maternal vitamin D deficiency and chronic helminth infections. Here, we investigated whether maternal Schistosoma haematobium affects maternal or cord vitamin D status as well as birth outcomes. In a prospective cross-sectional study of pregnant women conducted in Lambaréné, Gabon, we diagnosed maternal parasitic infections in blood, urine and stool. At delivery we measured vitamin D in maternal and cord blood. S. haematobium, soil-transmitted helminths, and microfilariae were found at prevalences of 30.2%, 13.0%, and 8.8%, respectively. Insufficient vitamin D and calcium levels were found in 28% and 15% of mothers, and in 11.5% and 1.5% of newborns. Mothers with adequate vitamin D had lower risk of low birthweight babies (aOR = 0.11, 95% CI 0.02-0.52, p = 0.01), whilst offspring of primipars had low cord vitamin D levels, and low vitamin D levels increased the risk of maternal inflammation. Maternal filariasis was associated with low calcium levels, but other helminth infections affected neither vitamin D nor calcium levels in either mothers or newborns. Healthy birth outcomes require maintenance of adequate vitamin D and calcium levels. Chronic maternal helminth infections do not disrupt those levels in a semi-rural setting in sub-Saharan Africa.

Dietary risk factors for hypertensive disorders of pregnancy

OBJECTIVE

To assess whether diet quality and specific dietary components are associated with hypertensive disorders of pregnancy (HDP).

STUDY DESIGN

Nested case control study in a prospectively collected cohort of 450 participants with singleton pregnancies who completed the National Institutes of Health Diet Health Questionnaire II (DHQ-II) in the third trimester or within 3 months of delivery. Patients with fetal anomalies, conception by in-vitro fertilization, and deliveries at outside hospitals were excluded from the original prospective cohort study. Cases were patients diagnosed with HDP and controls were patients without HDP. Cases and controls were matched by BMI class in a 1:2 ratio. Exposures of interest were HEI-2015 score components and other DHQ-II dietary components including minerals, caffeine, and water. These dietary components were compared between cohorts using univariate analyses.

MAIN OUTCOME MEASURES

HEI-2015 total scores representing diet quality, component scores, and objective background data between patients with HDP and patients without HDP.

RESULTS

150 patients with HDP were matched to 300 controls without HDP. Baseline demographics were similar between groups, including BMI. Patients with HDP were less likely to have high quality diets (HEI ≥ 70) than controls (7.3 % v 15.7 %, P = 0.02). HDP were associated with significantly higher dairy, saturated fat, and sodium intake compared to controls. Other components were similar between groups.

CONCLUSION

Patients with HDP are more likely to have lower diet quality and higher consumption of sodium, dairy, and saturated fats. These results can be used to study antenatal diet modification in patients at high risk of HDP.

Developing comprehensive woman hand-held case notes to improve quality of antenatal care in low-income settings: participatory approach with maternal health stakeholders in Malawi

BACKGROUND

In the quest for quality antenatal care (ANC) and positive pregnancy experience, the value of comprehensive woman hand-held case notes cannot be emphasised enough. However, the woman's health passport book in Malawi presents gaps which hinder provision of quality care, especially during pregnancy. We aimed to develop a compressive updated woman hand-held case notes tool (health passport book) which reflects WHO 2016 ANC guidelines in Malawi.

METHODS

From July 2022 to August 2022, we applied a co-creative participatory approach in 3 workshops with key stakeholders to compare the current ANC tool contents to the WHO 2016 ANC guidelines, decide on key elements to be changed to improve adherence and change in practice, and redesign the woman's health passport tool to reflect the changes. Within-group discussions led to whole-group discussions and consensus, guided by a modified nominal group technique. Facilitators guided the discussions while ensuring autonomy of the group members in their deliberations. Discussions were recorded and transcribed. Data was analysed through thematic analysis, and reduction and summaries in affinity diagrams. The developed tool was endorsed for implementation within Malawi's healthcare system by the national safe motherhood technical working group (TWG) in July 2023.

RESULTS

Five themes were identified in the analysis. These were (i) critical components in the current tool missed, (ii) reimagining the current ANC tool, (iii) opportunity for ultrasound scanning conduct and documentation, (iv) anticipated barriers related to implementation of the newly developed tool and (v) cultivating successful implementation. Participants further recommended strengthening of already existing policies and investments in health, strengthening public private partnerships, and continued capacity building of healthcare providers to ensure that their skill sets are up to date.

CONCLUSION

Achieving goals of quality ANC and universality of healthcare are possible if tools in practice reflect the guidelines set out. Our efforts reflect a pioneering attempt in Malawi to improve women's hand-held case notes, which we know help in enhancing quality of care and improve overall women's satisfaction with their healthcare system.

Optimizing perinatal wellbeing in pregnancy with obesity: a clinical trial with a multi-component nutrition intervention for prevention of gestational diabetes and infant growth and neurodevelopment impairment

Pregnancy complicated by obesity represents an increased risk of unfavorable perinatal outcomes such as gestational diabetes mellitus (GDM), hypertensive disorders in pregnancy, preterm birth, and impaired fetal growth, among others. Obesity is associated with deficiencies of micronutrients, and pregnant women with obesity may have higher needs. The intrauterine environment in pregnancies complicated with obesity is characterized by inflammation and oxidative stress, where maternal nutrition and metabolic status have significant influence and are critical in maternal health and in fetal programming of health in the offspring later in life. Comprehensive lifestyle interventions, including intensive nutrition care, are associated with a lower risk of adverse perinatal outcomes. Routine supplementation during pregnancy includes folic acid and iron; other nutrient supplementation is recommended for high-risk women or women in low-middle income countries. This study is an open label randomized clinical trial of parallel groups (UMIN Clinical Trials Registry: UMIN000052753, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000060194) to evaluate the effect of an intensive nutrition therapy and nutrient supplementation intervention (folic acid, iron, vitamin D, omega 3 fatty acids, myo-inositol and micronutrients) in pregnant women with obesity on the prevention of GDM, other perinatal outcomes, maternal and newborn nutritional status, and infant growth, adiposity, and neurodevelopment compared to usual care. Given the absence of established nutritional guidelines for managing obesity during pregnancy, there is a pressing need to develop and implement new nutritional programs to enhance perinatal outcomes.

Effect of low-molecular-weight heparin on placenta-mediated fetal growth restriction in a tertiary referral hospital: A 7-year retrospective cohort study

OBJECTIVE

To investigate the effect of low-molecular-weight heparin (LMWH) on placenta-mediated fetal growth restriction (FGR).

METHODS

A cohort of 570 pregnant women diagnosed with placenta-mediated FGR were enrolled from January 1, 2015 through to December 31, 2021. A birth database, including demographic data, antenatal complications, and detailed delivery and newborn data, was created to collect variables from the Hospital Information System (HIS) Database. The unique personal registration number, assigned to each patient on first registration with HIS in the West China Second University Hospital, was used to link these patients. LMWH use was defined as at least 1-week prescription from diagnosis of placenta-mediated FGR. Pregnant women received LMWH (Enoxaparin 4000 IU/day) by self-administered subcutaneous injection only when they agreed and signed informed consent. Primary outcome was intrauterine fetal death after 20 weeks of pregnancy. Secondary outcomes included preterm birth (PB), Apgar score less than 7 at 1 min, admission to neonatal intensive care unit (NICU), and birth weight. Logistic regression analysis was conducted to compute adjusted odds ratio (aOR) with 95% confidence intervals (CI) for outcomes.

RESULTS

After controlling for confounders, LMWH use was associated with a decreased risk of intrauterine fetal death (aOR 2.49, 95% CI 1.35-4.57, P = 0.003), PB before 37 weeks of pregnancy (aOR 3.35, 95% CI 2.14-5.23, P < 0.001), PB before 34 weeks of pregnancy (aOR 2.25, 95% CI 1.36-3.74, P = 0.002), Apgar score less than 7 at 1 min (aOR 2.25, 95% CI 1.36-3.74, P = 0.002), NICU admission (aOR 2.29, 95% CI 1.48-3.55, P < 0.001). Using LMWH increased the mean birth weight in PB before 32 weeks of pregnancy (mean ± standard deviation [SD] 1126.4 ± 520.0 g, P = 0.020), PB before 37 weeks of pregnancy (mean ± SD 1563.9 ± 502.7 g, P = 0.019), early-onset FGR (mean ± SD 2125.2 ± 665.7 g, P < 0.001), late-onset FGR (mean ± SD 2343.4 ± 507.9, P < 0.001), and non-severe FGR (mean ± SD 2231.1 ± 607.2 g, P < 0.001).

CONCLUSION

Use of LMWH can significantly improve the fetal and neonatal outcomes among pregnant women with placenta-mediated FGR, particularly reducing the risk of intrauterine fetal death.

Mendelian randomization supports genetic liability to hospitalization for COVID-19 as a risk factor of pre-eclampsia

Background

Pre-eclampsia and eclampsia are among the major threats to pregnant women and fetuses, but they can be mitigated by prevention and early screening. Existing observational research presents conflicting evidence regarding the causal effects of coronavirus disease 2019 (COVID-19) on pre-eclampsia risk. Through Mendelian randomization (MR), this study aims to investigate the causal effect of three COVID-19 severity phenotypes on the risk of pre-eclampsia and eclampsia to provide more rigorous evidence.

Methods

Two-sample MR was utilized to examine causal effects. Summary-level data from genome-wide association studies (GWAS) of individuals of European ancestry were acquired from the GWAS catalog and FinnGen databases. Single-nucleotide polymorphisms associated with COVID-19 traits at p < 5 × -8 were obtained and pruned for linkage disequilibrium to generate instrumental variables for COVID-19. Inverse variance weighted estimates were used as the primary MR results, with weighted median and MR-Egger as auxiliary analyses. The robustness of the MR findings was also evaluated through sensitivity analyses. Bonferroni correction was applied to primary results, with a p < 0.0083 considered significant evidence and a p within 0.083-0.05 considered suggestive evidence.

Results

Critical ill COVID-19 [defined as hospitalization for COVID-19 with either a death outcome or respiratory support, OR (95% CI): 1.17 (1.03-1.33), p = 0.020] and hospitalized COVID-19 [defined as hospitalization for COVID-19, OR (95% CI): 1.10 (1.01-1.19), p = 0.026] demonstrated suggestive causal effects on pre-eclampsia, while general severe acute respiratory syndrome coronavirus 2 infection did not exhibit a significant causal effect on pre-eclampsia. None of the three COVID-19 severity phenotypes exhibited a significant causal effect on eclampsia.

Conclusions

Our investigation demonstrates a suggestive causal effect of genetic susceptibility to critical ill COVID-19 and hospitalized COVID-19 on pre-eclampsia. The COVID-19 severity exhibited a suggestive positive dose-response relationship with the risk of pre-eclampsia. Augmented attention should be paid to pregnant women hospitalized for COVID-19, especially those needing respiratory support.

Association between calcium supplementation and gestational hypertension, and preeclampsia: A Meta-analysis of 26 randomized controlled trials

BACKGROUND

Pre-eclampsia and eclampsia are common causes of morbidity and mortality, especially in low-income countries. Reducing adverse outcomes associated with hypertensive disorders of pregnancy has been the ultimate priority in recent years. We aim to evaluate the association between calcium supplementation and preeclampsia and gestational hypertension risk among pregnant women.

METHODS

A systematic literature search was performed in electronic databases from inception to 15th July 2023, including only randomized controlled trials. Odds ratio (OR) were, and their corresponding 95% confidence interval (95% CI).

RESULTS

A total of 26 studies with 20,038 patients (10,003 patients with calcium supplements and 10,035 patients with placebo group) were included in the analysis. The Pooled analysis of primary outcome shows that calcium supplements reduce the risk of preeclampsia by 49% (OR, 0.51(95%CI: 0.40-0.66), P<0.001), and reduce the risk of gestational hypertension by 30% (OR, 0.70 (95%CI: 0.58-0.85)), P<0.001) compared to placebo. There was a trend of lower incidence of preterm delivery (OR, 0.88 (95%CI: 0.71-1.09), P=0.23), labor induction (OR, 0.90 (95%CI: 0.78-1.03), P=0.13), small for gestational age (OR, 0.70 (95% CI:0.37-1.32), P = 0.27), low birth weight (OR, 0.96 (95%CI: 0.86-1.08), P=0.53), perinatal mortality (OR, 0.88 (95%CI: 0.72-1.09), P=0.24), and maternal mortality (OR, 0.48 (95%CI: 0.12-1.84), P=0.28) among calcium supplementation group compared with the placebo group, however, statistical signifance was not achieved.

CONCLUSION

This study shows that calcium supplements are associated with a significant reduction in the risk of preeclampsia and gestational hypertension and a trend toward better maternal and fetal-related outcomes.

Role of mineral nutrients other than iron in pregnancy: under recognized opportunities to improve maternal/fetal outcomes: a literature review

BACKGROUND

Anemia during pregnancy is an important global health concern, affecting 40% of women worldwide, and iron deficiency shares a significant proportion of the burden. From conception to birth, pregnancy is a period when women undergo metabolic and physiological changes. The nutritional needs are higher during pregnancy; thus, adequate nutrition is essential to maintain fetal growth and development. However, adverse effects due to deficiency in nutrition during pregnancy can result in maternal, fetal and neonatal complications. Despite the multifactorial etiology of anemia, iron deficiency is assumed as the primary cause of anemia during pregnancy and hence, mitigation strategy pivots around it for anemia management. Therefore, excluding other contributors, a single-micronutrient approach with iron supplements remains a myopic approach and this can exacerbate iron deficiency anemia. Micronutrient deficiencies are of particular concern as they may pose a silent threat to the survival and well-being of reproductive-age women and their infants.

AIM

Micronutrients, especially trace minerals, play a myriad of roles in pregnancy, and the lack of each one causes adverse complications to both the mother and the fetus. In this review paper, we attempt to piece together available information regarding the adverse effects of abnormal trace mineral levels along with iron deficiency on the mother and the fetus.

METHOD

A non-systematic literature search in PubMed, Google Scholar, and the Cochrane databases, for publications on minerals and vitamins during pregnancy and the possible influence of supplements on pregnancy outcomes.

CONCLUSION

Micronutrient deficiency exacerbates the pregnancy-induced anemia and other adverse birth outcomes. Micronutrient supplementation during pregnancy can combat anemia as well as reduce a number of adverse pregnancy outcomes in a comprehensive manner.

Low-Dose Antenatal Calcium Supplementation: An Intervention Ready for Prime Time

New evidence of the effectiveness of low-dose antenatal calcium supplementation for preventing preeclampsia and preterm birth provides additional protection for pregnant women and their newborns in settings where calcium intake is low.

Managing pre-existing diabetes prior to and during pregnancy

Women with pre-existing diabetes who are planning a pregnancy ideally should receive high-quality, multidisciplinary preconception care in a specialist centre; this has been shown to improve pregnancy outcomes. Optimising glycaemic management is essential prior to conception and throughout pregnancy and breastfeeding to minimise adverse events. Low-dose aspirin is recommended from 12 weeks gestation for prevention of pre-eclampsia. Breastfeeding is highly advantageous in women with pre-existing diabetes; women often need additional support with establishment and maintenance of breastfeeding. High-quality postpartum care and effective contraception are essential.

An association of deficiencies in balanced dietary practices and inadequate iron and folic acid supplement's intake during pregnancy and increasing risk of pre-eclampsia or eclampsia among Indian women

Pre-eclampsia or eclampsia is a serious reproductive health problem which can cause maternal, fetal and neonatal morbidity and mortality worldwide. However till the notable reasons of it is not very clear at all. The main essence of the present study was to examine the association between dietary intake, iron and folic acid consumption during pregnancy and the chances of occurrences of pre-eclampsia or eclampsia among Indian women. A cross sectional observational study was performed by using NFHS-5 (2019-21) data. 190,797 ever married women aged between 15-49 years who had a live birth in the past five years preceding the survey were availed for this study. Multivariable logistic regression analysis was carried out to find out the association between dietary and supplementary intake and occurrences of eclampsia. About 3.6% of the sample women had pre-eclampsia or eclampsia. The results of the study indicated that the likelihood of the prevalence of pre-eclampsia or eclampsia was significantly higher among those women who did not take adequate diet and as well as not consumed iron and folic acid tablet or syrup for at least 90 days during pregnancy compared to those women who took adequate diet and iron and folic acid supplementation even after controlling some maternal, health and lifestyle, socio-economic and demographic characteristics. Integrated and quality ANC services can only ensure adequate nutritional intake in terms of healthy and balanced diet. So, quality ANC services and with this micronutrients intake could be an effective way to reduce the prevalence of pre-eclampsia or eclampsia.

Maternal-neonatal events resulting from medications for preventing hypertensive disorders in high-risk pregnant women: A systematic review and network meta-analysis

BACKGROUND

There have been few studies reporting on maternal and neonatal events in high-risk pregnant women receiving medications for preventing hypertensive disorders of pregnancy (HDP).

OBJECTIVE

To identify placental abruption, postpartum hemorrhage, neonatal intraventricular hemorrhage, and neonates with small for gestational age (SGA) or growth restriction resulting from medications for preventing HDP in high-risk pregnant women using a network meta-analysis.

SEARCH STRATEGY

All randomized controlled trials comparing the most commonly used medications (antiplatelet agents, anticoagulants, antioxidants, nitric oxide, and calcium) for preventing HDP in high-risk pregnant women were searched from the Cochrane Pregnancy and Childbirth's Specialized Register of Controlled Trials until July 31, 2020, without language restriction.

SELECTION CRITERIA

Two of the authors independently selected the eligible trials.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the methodological quality of the included trials. Pairwise and network meta-analyses were used to determine comparative risk ratios and 95% confidence intervals.

MAIN RESULTS

The 51 included trials involved 69 669 pregnant women. Compared with placebo/no treatment, antioxidants slightly reduced placental abruption with high-certainty evidence. Antiplatelet agents probably reduced SGA with low-certainty evidence and slightly increased neonatal intraventricular hemorrhage with moderate-certainty evidence.

CONCLUSION

Antiplatelet agents probably reduce SGA, but neonatal intraventricular hemorrhage should be monitored.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42018096276.

Factors affecting the implementation of calcium supplementation strategies during pregnancy to prevent pre-eclampsia: a mixed-methods systematic review

OBJECTIVES

Daily calcium supplements are recommended for pregnant women from 20 weeks' gestation to prevent pre-eclampsia in populations with low dietary calcium intake. We aimed to improve understanding of barriers and facilitators for calcium supplement intake during pregnancy to prevent pre-eclampsia.

DESIGN

Mixed-method systematic review, with confidence assessed using the Grading of Recommendations, Assessment, Development and Evaluations-Confidence in the Evidence from Reviews of Qualitative research approach.

DATA SOURCES

MEDLINE and EMBASE (via Ovid), CINAHL and Global Health (via EBSCO) and grey literature databases were searched up to 17 September 2022.

ELIGIBILITY CRITERIA

We included primary qualitative, quantitative and mixed-methods studies reporting implementation or use of calcium supplements during pregnancy, excluding calcium fortification and non-primary studies. No restrictions were imposed on settings, language or publication date.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed risk of bias. We analysed the qualitative data using thematic synthesis, and quantitative findings were thematically mapped to qualitative findings. We then mapped the results to behavioural change frameworks to identify barriers and facilitators.

RESULTS

Eighteen reports from nine studies were included in this review. Women reported barriers to consuming calcium supplements included limited knowledge about calcium supplements and pre-eclampsia, fears and experiences of side effects, varying preferences for tablets, dosing, working schedules, being away from home and taking other supplements. Receiving information regarding pre-eclampsia and safety of calcium supplement use from reliable sources, alternative dosing options, supplement reminders, early antenatal care, free supplements and support from families and communities were reported as facilitators. Healthcare providers felt that consistent messaging about benefits and risks of calcium, training, and ensuring adequate staffing and calcium supply is available would be able to help them in promoting calcium.

CONCLUSION

Relevant stakeholders should consider the identified barriers and facilitators when formulating interventions and policies on calcium supplement use. These review findings can inform implementation to ensure effective and equitable provision and scale-up of calcium interventions.

PROSPERO REGISTRATION NUMBER

CRD42021239143.

Approach to Pregnancy in Patients With Lupus Nephritis

Active lupus nephritis (LN) in pregnancy is strongly associated with poor maternal and fetal outcomes and, therefore, has implications on the planning, timing, and management. Prepregnancy evaluation is essential for all LN patients with childbearing potential to ensure pregnancies proceed in a safe and timely manner. Both maternal and fetal risks are communicated to patient during the evaluation. Stratification into different risk profile groups is then made based on disease activity and organ impairment severity. Patients with LN are generally divided into 3 main groups. Patients with LN who become pregnant receive treatments that are nonteratogenic and optimal for fetal and maternal outcomes. Throughout the pregnancy period, these patients are monitored closely under surveillance by a multidisciplinary team of clinicians. The management of patients with LN in pregnancy can be challenging both diagnostically (distinguishing LN from pre-eclampsia and determining the role and timing of kidney biopsy) and therapeutically (LN flares during pregnancy and managing a newly diagnosed LN during pregnancy).

Causal relationship association of cheese intake with gestational hypertension and diabetes result from a Mendelian randomization study

BACKGROUND

The evidence from observational studies has been inconclusive on the causal relationship between cheese intake and gestational hypertension or diabetes.

AIM

To determine whether cheese consumption was causally related to hypertension and diabetes during pregnancy.

METHODS

This was a two-sample Mendelian randomized (MR) study. Summary-level genetic data for cheese intake was exposure and corresponding outcome data for gestational hypertension and gestational diabetes were extracted from the IEU OpenGWAS database. MR analysis was conducted using inverse variance weighting. For sensitivity analyses, MR-Egger regression, weighted median, weighted mode, and leave-one-out methods were conducted. A fixed-effect model was used to meta-analyze two sample MR estimates. The traits of gestational hypertension were pregnancy hypertension (123579 individuals) and oedema, proteinuria and hypertensive disorders in pregnancy, childbirth and the puerperium (123579 individuals), and traits of gestational diabetes were gestational diabetes (123579 individuals) and diabetes mellitus in pregnancy (116363 individuals), respectively.

RESULTS

Cheese intake per standard deviation increase has causally reduced the risks of gestational hypertension [odds ratio (OR) = 0.60, 95% confidence interval (CI): 0.47-0.76, P < 0.001] and gestational diabetes (OR = 0.41, 95%CI: 0.30-0.55, P < 0.001) in inverse variance weighted analysis. Sensitivity analysis showed no heterogeneity (all P > 0.05) nor horizontal pleiotropy (all P > 0.05) in the relationship between cheese intake and gestational hypertension, but heterogeneity presented (all P < 0.05) in relation to gestational diabetes in the two-sample MR analysis.

CONCLUSION

Cheese intake was inversely associated with gestational hypertension and gestational diabetes in MR analysis, suggesting that cheese consumption may be beneficial in preventing hypertension and diabetes during pregnancy.

The association between dietary mineral intake and the risk of preeclampsia in Chinese pregnant women: a matched case-control study

Previous studies on the relationship between dietary minerals and preeclampsia (PE) have given inconsistent results. The aim of this study was to further clarify the relationship between dietary minerals intake and PE in Chinese pregnant women. In this study, 440 pairs of hospital-based preeclamptic and healthy women were matched 1:1. Dietary intake was obtained through a 78-item semi-quantitative food frequency questionnaire. Multivariate conditional logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). Restricted cubic splines were plotted to evaluate the dose-response relationship between dietary minerals intake and PE. This study found significant inverse associations for dietary intake of calcium, magnesium, phosphorus, iron, copper, manganese and zinc and the risk of PE in both univariate and multivariate models (all P- trend < 0.05). After adjusting for possible confounders, compared with the lowest quartile, the odds ratio of the highest quartile was 0.74 (95% CI 0.56-0.98) for calcium, 0.63 (95% CI 0.42-0.93) for magnesium, 0.45 (95% CI 0.31-0.65) for phosphorus, 0.44 (95% CI 0.30-0.65) for iron, 0.72 (95% CI 0.53-0.97) for copper, 0.66 (95% CI 0.48-0.91) for manganese and 0.38 (95% CI 0.25-0.57) for zinc. In addition, a reverse J-shaped relationship between dietary minerals intake and PE risk was observed (P-overall association < 0.05). In Chinese pregnant women, a higher intake of dietary minerals, including calcium, magnesium, phosphorus, copper, iron, manganese, and zinc was associated with a lower odds of PE.

Methodology for Isolation of miRNA From the Serum of Women Investigated for Pre-eclampsia

Background Pre-eclampsia remains a leading cause of maternal and foetal mortality with a poorly understood pathophysiology. It can lead to a range of clinical presentations, but proteinuria and hypertension are key components of the diagnosis. These signs arise due to disordered placental implantation due to poor trophoblastic invasion, resulting in placental oxidative stress due to hypoxia. Oxidative stress triggers the release of syncytiotrophoblast microvesicles (STMBs), of which placenta-derived exosomes may be a key component. The high specificity of exosomes for their cell of origin makes them ideal candidates as diagnostic biomarkers. We are particularly interested in the miRNAs (microRNAs) contained within these exosomes, as they may give us an insight into the genomic regulation within the pre-eclamptic placenta that leads to the disease state. The development of workflows for miRNA quantitation may enable us to identify novel biomarkers. Methods We extracted exosomes and purified total RNA from 23 serum samples using the Norgen Plasma/Serum Exosome Purification and RNA Isolation Midi Kit. We then used the bioanalyser to determine the concentration and quality of the RNA obtained. It uses rapid electrophoresis, requires minimal sample sizes, and can assess the quality of genetic material as small as 25 bases. Results We have successfully isolated RNA from these samples; however, the concentration of the total RNA was too low for downstream molecular analysis. We did gain insight into how to optimise and develop the workflow so that, with each attempt, the yield increased. Our greatest concentrations were obtained by combining serum samples from multiple patients, demonstrating that we needed a higher volume to optimise the yield. Future studies should aim to obtain samples specifically for use in this research so that we can process a larger volume of serum. Conclusions We have also noted that there is a positive correlation between the overall concentration of total RNA and a high sFlt-1/PlGF ratio. Preliminary analysis from Illumina identified with a high degree of confidence the presence of three miRNAs, namely, mir-498(46), mir-122(1), and mir-134(41). Further work is necessary to validate these findings and should focus on the possible future role of these miRNAs as biomarkers for the early diagnosis of pre-eclampsia.

The relationship between the intake of fruits, vegetables, and dairy products with hypertension: findings from the STEPS study

BACKGROUND

The current research aimed to evaluate the relationship between fruit, vegetable (FV), and dairy consumption with the odds of developing hypertension based on nationwide Stepwise approach to surveillance (STEPS) data in Iran.

METHODS

This cross-sectional study was accomplished by the research center of non-communicable diseases (NCDs) in Tehran. In total, 29,378 individuals' data were analyzed. Participants were classified into normal, elevated BP, stage I, and stage II hypertension according to systolic blood pressure (SBP) and diastolic blood pressure (DBP) examinations. Based on the STEPS questionnaire, the consumption of FVs and dairy products was evaluated. Multinomial logistic regression was applied to assess the relationship between the consumption of FVs and dairy products with hypertension.

RESULTS

The findings revealed that only fruit consumption (≥ 2 servings/day) was negatively related to stage I hypertension (odds ratio (OR) = 0.81; 95% confidence interval (CI): 0.69-0.95) in two servings per day and OR = 0.81; 95% CI: 0.68-0.96 in > two servings per day) in the adjusted model. There was no significant relationship between consuming vegetables and dairy products with elevated BP and hypertension.

CONCLUSION

Our study showed that increasing fruit consumption was related to reducing hypertension odds. Regarding the consumption of dairy products and vegetables, no significant relationship was found with the odds of hypertension. More studies, especially cohorts, are needed to evaluate the impacts of FV and dairy products on the risk of hypertension.

Effect of the Dietary Approaches to Stop Hypertension (DASH) diet on the development of preeclampsia and metabolic outcomes in pregnant women with pre-existing diabetes mellitus: a randomised, controlled, single-blind trial

Preeclampsia (PE) affects up to five times more women with pre-existing diabetes mellitus (PDM) than women without it. The present study aimed to identify the effect of the DASH diet on PE incidence (primary outcome) and blood pressure, glycated haemoglobin (GH), serum lipids, glutathione peroxidase (GP), C-reactive protein (CRP - secondary outcomes) in pregnant with PDM. This randomised, controlled, single-blind trial studied sixty-eight pregnant women with PDM throughout prenatal care until delivery (18 weeks) at a public maternity hospital, Brazil. The standard diet group (SDG) received a diet containing 45-65 % carbohydrates, 15-20 % protein and 25-30 % lipids. The DASH diet group (DDG) received the adapted DASH diet with a similar macronutrient distribution, but with a higher concentration of fibres, unsaturated fats, calcium, magnesium and potassium as well as lower saturated fat. Student's t, Mann-Whitney U and the Chi-square tests were used to compare outcomes. PE incidence was 22⋅9 % in the SDG and 12⋅1 % in the DDG (P = 0⋅25). GP levels significantly increased in the DDG (intra-group analysis; mean difference = 1588 [CI 181, 2994], P = 0⋅03) and tended to be different from the variation in the SDG (mean difference = -29⋅5 [CI -1305; 1⋅365]; v. DDG: 1588 [CI 181; 2994], P = 0⋅09). GH levels decreased significantly and similarly between groups (SDG: -0⋅61 [CI -0⋅26, -0⋅96], P = 0⋅00) v. DDG: -1⋅1 [CI -0⋅57, -1⋅62], P = 0⋅00). There was no evidence of a difference in PE incidence at the end of the intervention between the two diets. The DASH diet seems to favour PE-related biochemical markers.

Could local foods achieve recommended calcium intakes for nutritionally vulnerable populations in Uganda, Guatemala, and Bangladesh?

Globally, dietary intake of calcium is often insufficient, and it is unclear if adequacy could be achieved by promoting calcium-rich local foods. This study used linear programming and household consumption data from Uganda, Bangladesh, and Guatemala to assess whether local foods could meet calcium population reference intakes (Ca PRIs). The most promising food-based approaches to promote dietary calcium adequacy were identified for 12- to 23-month-old breastfed children, 4- to 6-year-old children, 10- to 14-year-old girls, and nonpregnant and nonbreastfeeding (NPNB) women of reproductive age living in two regions of each country. Calcium-optimized diets achieved 75-253% of the Ca PRI, depending on the population, and were <100% for 4- to 6-year-olds in one region of each country and 10- to 14-year-old girls in Sylhet, Bangladesh. The best food sources of calcium were green leafy vegetables and milk, across geographic locations, and species of small fish, nixtamalized (lime-treated) maize products, sesame seeds, and bean varieties, where consumed. Food-based recommendations (FBRs) achieving the minimum calcium threshold were identified for 12- to 23-month-olds and NPNB women across geographic locations, and for 4- to 6-year-olds and 10-to 14-year-old girls in Uganda. However, for 4- to 6-year-olds and 10- to 14-year-old girls in Bangladesh and Guatemala, calcium-adequate FBRs could not be identified, indicating a need for alternative calcium sources or increased access to and consumption of local calcium-rich foods.

Hypertensive disorders of pregnancy

Hypertensive disorders of pregnancy (HDP) are one of the most commonly occurring complications of pregnancy and include chronic hypertension, gestational hypertension, and pre-eclampsia. New developments in early pregnancy screening to identify women at high risk for pre-eclampsia combined with targeted aspirin prophylaxis could greatly reduce the number of affected pregnancies. Furthermore, recent advances in the diagnosis of pre-eclampsia, such as placental growth factor based testing, have been shown to improve the identification of those pregnancies at highest risk of severe complications. Evidence from trials has refined the target blood pressure and timing of delivery to manage chronic hypertension and pre-eclampsia with non-severe features, respectively. Importantly, a wealth of epidemiological data now links HDP to future cardiovascular disease and diabetes decades after an affected pregnancy. This review discusses the current guidelines and research data on the prevention, diagnosis, management, and postnatal follow-up of HDP. It also discusses the gap in knowledge regarding the long term risks for cardiovascular disease following HDP and illustrates the importance of improving adherence to postnatal guidelines to monitor hypertension and the need for more research focused on primary prevention of future cardiovascular disease in women identified as being at high risk because of HDP.

Hypertension in Pregnancy: A Diagnostic and Therapeutic Overview

Hypertensive disorders in pregnancy are associated with increased risk of maternal, fetal, and neonatal morbidity and mortality. It is important to distinguish between pre-existing (chronic) hypertension and gestational hypertension, developing after 20 weeks of gestation and usually resolving within 6 weeks postpartum. There is a consensus that systolic blood pressure ≥ 170 or diastolic blood pressure ≥ 110 mmHg is an emergency and hospitalization is indicated. The selection of the antihypertensive drug and its route of administration depend on the expected time of delivery. The current European guidelines recommend initiating drug treatment in pregnant women with persistent elevation of blood pressure ≥ 150/95 mmHg and at values > 140/90 mmHg in women with gestational hypertension (with or without proteinuria), with pre-existing hypertension with the superimposition of gestational hypertension, and with hypertension with subclinical organ damage or symptoms at any time during pregnancy. Methyldopa, labetalol, and calcium antagonists (the most data are available for nifedipine) are the drugs of choice. The results of the CHIPS and CHAP studies are likely to reduce the threshold for initiating treatment. Women with a history of hypertensive disorders in pregnancy, particularly those with pre-eclampsia, are at high risk of developing cardiovascular disease later in life. Obstetric history should become a part of the cardiovascular risk assessment in women.

Calcium supplementation to prevent pre-eclampsia: protocol for an individual participant data meta-analysis, network meta-analysis and health economic evaluation

INTRODUCTION

Low dietary calcium intake is a risk factor for pre-eclampsia, a major contributor to maternal and perinatal mortality and morbidity worldwide. Calcium supplementation can prevent pre-eclampsia in women with low dietary calcium. However, the optimal dose and timing of calcium supplementation are not known. We plan to undertake an individual participant data (IPD) meta-analysis of randomised trials to determine the effects of various calcium supplementation regimens in preventing pre-eclampsia and its complications and rank these by effectiveness. We also aim to evaluate the cost-effectiveness of calcium supplementation to prevent pre-eclampsia.

METHODS AND ANALYSIS

We will identify randomised trials on calcium supplementation before and during pregnancy by searching major electronic databases including Embase, CINAHL, MEDLINE, CENTRAL, PubMed, Scopus, AMED, LILACS, POPLINE, AIM, IMSEAR, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform, without language restrictions, from inception to February 2022. Primary researchers of the identified trials will be invited to join the International Calcium in Pregnancy Collaborative Network and share their IPD. We will check each study's IPD for consistency with the original authors before standardising and harmonising the data. We will perform a series of one-stage and two-stage IPD random-effect meta-analyses to obtain the summary intervention effects on pre-eclampsia with 95% CIs and summary treatment-covariate interactions (maternal risk status, dietary intake, timing of intervention, daily dose of calcium prescribed and total intake of calcium). Heterogeneity will be summarised using tau2, I2 and 95% prediction intervals for effect in a new study. Sensitivity analysis to explore robustness of statistical and clinical assumptions will be carried out. Minor study effects (potential publication bias) will be investigated using funnel plots. A decision analytical model for use in low-income and middle-income countries will assess the cost-effectiveness of calcium supplementation to prevent pre-eclampsia.

ETHICS AND DISSEMINATION

No ethical approvals are required. We will store the data in a secure repository in an anonymised format. The results will be published in peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42021231276.

Understanding challenges as they impact on hospital-level care for pre-eclampsia in rural Ethiopia: a qualitative study

OBJECTIVE

To explore hospital-level care for pre-eclampsia in Ethiopia, considering the perspectives of those affected and healthcare providers, in order to understand barriers and facilitators to early detection, care escalation and appropriate management.

SETTING

A primary and a general hospital in southern Ethiopia.

PARTICIPANTS

Women with lived experience of pre-eclampsia care in the hospital, families of women deceased due to pre-eclampsia, midwives, doctors, integrated emergency surgical officers and healthcare managers.

RESULTS

This study identified numerous systemic barriers to provision of quality, person-centred care for pre-eclampsia in hospitals. Individual staff efforts to respond to maternal emergencies were undermined by a lack of consistency in availability of resources and support. The ways in which policies were applied exacerbated inequities in care. Staff improvised as a means of managing with limited material or human resources and knowledge. Social hierarchies and punitive cultures challenged adequacy of communication with women, documentation of care given and supportive environments for quality improvement.

CONCLUSIONS

Quality care for pre-eclampsia requires organisational change to create a safe space for learning and improvement, alongside efforts to offer patient-centred care and ensure providers are equipped with knowledge, resources and support to adhere to evidence-based practice.

Dietary supplements and vascular function in hypertensive disorders of pregnancy

Hypertensive disorders of pregnancy are complications that can lead to maternal and infant mortality and morbidity. Hypertensive disorders of pregnancy are generally defined as hypertension and may be accompanied by other end organ damages including proteinuria, maternal organ disturbances including renal insufficiency, neurological complications, thrombocytopenia, impaired liver function, or uteroplacental dysfunction such as fetal growth restriction and stillbirth. Although the causes of these hypertensive disorders of pregnancy are multifactorial and elusive, they seem to share some common vascular-related mechanisms, including diseased spiral arteries, placental ischemia, and endothelial dysfunction. Recently, preeclampsia is being considered as a vascular disorder. Unfortunately, due to the complex etiology of preeclampsia and safety concerns on drug usage during pregnancy, there is still no effective pharmacological treatments available for preeclampsia yet. An emerging area of interest in this research field is the potential beneficial effects of dietary intervention on reducing the risk of preeclampsia. Recent studies have been focused on the association between deficiencies or excesses of some nutrients and complications during pregnancy, fetal growth and development, and later risk of cardiovascular and metabolic diseases in the offspring. In this review, we discuss the involvement of placental vascular dysfunction in preeclampsia. We summarize the current understanding of the association between abnormal placentation and preeclampsia in a vascular perspective. Finally, we evaluate several studied dietary supplementations to prevent and reduce the risk of preeclampsia, targeting placental vascular development and function, leading to improved pregnancy and postnatal outcomes.

The utilization of systematic review evidence in formulating India's National Health Programme guidelines between 2007 and 2021

Evidence-informed policymaking integrates the best available evidence on programme outcomes to guide decisions at all stages of the policy process and its importance becomes more pronounced in resource-constrained settings. In this paper, we have reviewed the use of systematic review evidence in framing National Health Programme (NHP) guidelines in India. We searched official websites of the different NHPs, linked to the main website of the Ministry of Health and Family Welfare (MoHFW), in December 2020 and January 2021. NHP guideline documents with systematic review evidence were identified and information on the use of this evidence was extracted. We classified the identified systematic review evidence according to its use in the guideline documents and analysed the data to provide information on the different factors and patterns linked to the use of systematic review evidence in these documents. Systematic reviews were mostly visible in guideline documents addressing maternal and newborn health, communicable diseases and immunization. These systematic reviews were cited in the guidelines to justify the need for action, to justify recommendations for action and opportunities for local adaptation, and to highlight implementation challenges and justify implementation strategies. Guideline documents addressing implementation cited systematic reviews about the problems and policy options more often than citing systematic reviews about implementation. Systematic reviews were linked directly to support statements in few guideline documents, and sometimes the reviews were not appropriately cited. Most of the systematic reviews providing information on the nature and scale of the policy problem included Indian data. It was seen that since 2014, India has been increasingly using systematic review evidence for public health policymaking, particularly for some of its high-priority NHPs. This complements the increasing investment in research synthesis centres and procedures to support evidence-informed decision making, demonstrating the continued evolution of India's evidence policy system.

The prevalence of trimester-specific dietary supplements and associated factors during pregnancy: An observational study

Objectives: This study aimed to assess the prevalence of trimester-specific dietary supplements (DS)s use and their possible correlates during pregnancy.

Method: Pregnant women were convenience sampled and recruited from a comprehensive obstetric care center in Shanghai, China. Data relating to the use of DS during pregnancy, social support and other social-demographic and obstetric data were collected. Trimester-specific DS use and factors related DS were explored.

Results: Of the 2803 women participating in this study, 94.8%, 96.2%, 93.8%, and 94.4% reported the use of at least one DS during pregnancy (all trimesters) and in the first, second, and third trimesters of pregnancy, respectively. Significant differences were noted in the use of DS containing folic acid, calcium, iron, vitamins, and docosahexaenoic acid (DHA), during the three trimesters of pregnancy. A higher proportion of DS use was negatively associated with certain categories of pregnant woman, including unemployed/housewife, low education level, obese, and low social support. A positive association was identified with gestational age.

Conclusion for practice: Considering the high prevalence of DS use during pregnancy, future studies are needed to evaluate the accuracy and suitability of DS usage during pregnancy.

Nutritional Status and Nutrients Related to Pre-Eclampsia Risk

Elevated blood pressure during pregnancy, pre-eclampsia, is in part a result of inflammatory processes related to pregnancy. Reducing risk for pre-eclampsia is important to improve birth outcomes and reduce morbidity and mortality. Nutritional status and dietary intake of key foods and nutrients can aid in the reduction of pre-eclampsia risk. Excessive gestational weight gain is associated with pre-eclampsia risk, however, fluid retention, may be the driver of this relationship. While diets rich in fruits, vegetables, and dietary fiber can reduce pre-eclampsia risk and adherence to a western diet pattern can increase risk. Other nutrients, which may improve hypertension, such as sodium or salt, have little to no effect on pre-eclampsia risk. Key nutrients impacting pre-eclampsia risk are described in this article.

Trends and risk factors of stillbirth among women of reproductive age in Pakistan: A multivariate decomposition analysis

Background

Every year, 2 million babies are stillborn in the world. Globally, there has been a decline in the stillbirth rate of 2%. Despite advancements in prenatal care and the implementation of new medical technologies, the incidence of early stillbirths remains unchanged. A slight decrease in the rate of late-term stillbirth has been observed. Pakistan ranked third in South Asia for having the highest stillbirth rate. Compared to its neighbors and other developing nations, Pakistan has shown a lack of progress in reducing maternal and neonatal fatalities. Therefore, the purpose of this study is to use a multivariate decomposition analysis to examine the trends and factors that have contributed to the change in the stillbirth rate over time.

Methods

To conduct this study, we used a secondary data analysis approach and analyzed data from the Pakistan Demographic and Health Survey (PDHS) of 2012-2013 and 2017-2018). For the analysis, a total sample of 15,068 births in 2017-2018 and 13,558 births in the PDHS from 2012 to 2013 were taken into account. Using the MVDCMP function within STATA version 15 statistical software, a logit-based multivariate decomposition model was fitted to determine the variables that influence the change in stillbirth. The current study used two cross-sectional surveys to identify important risk factors for stillbirths.

Results

Over the past 5 years, Pakistan's stillbirth rate has risen from 3.98 to 5.75%. According to the total multivariate decomposition analysis, the change in coefficient (change in the effect of attributes) accounted for 81.17% of the overall change in the proportion of stillbirths. In contrast, the change in endowment was not statistically significant. Changes in maternal education, individual and community-level wealth status, and mode of delivery all significantly impacted the rate of stillbirths over time.

Conclusion

Stillbirths increased in Pakistan from 2012 to 2017. Stillbirths are observed more frequently for women residing in Punjab, Sindh, and rural areas. A major concern that is directly related to the prevalence of stillbirths in Pakistan is the lack of accessible, affordable, and high-quality maternal healthcare facilities. Older, overweight, and uneducated women are more likely to have stillbirths than women who deliver vaginally. High parity and short birth intervals also accelerated the rate of stillbirths. An effective remedy to control stillbirths is the provision of accessible and affordable healthcare services. Awareness campaigns for the health education of pregnant women should focus on raising awareness to support better pregnancy outcomes for poor women living in communities with higher education levels. The risk of stillbirth can be reduced by offering free diagnostics for early detection of birth complications in low-resource settings and referring these cases to knowledgeable gynecologists for safe delivery.

Should all pregnant women take calcium supplements in Nepal? GRADE evidence to policy assessment

Background

The WHO recommends oral calcium supplementation (1.5–2.0 g) in pregnant women to reduce the risk of pre-eclampsia living in areas with low dietary calcium intake. Although maternal mortality is high in Nepal and eclampsia causes at least 20% of maternal deaths, implementing WHO recommendations would be a major undertaking.

Objective

This review aimed to assess whether the current evidence supports the blanket supplementation of calcium to prevent pre-eclampsia among pregnant women in Nepal.

Methods

We used a structured approach to appraise the evidence for calcium supplementation in Nepal. We identified what may influence the impact of calcium supplementation in Nepal and conducted a situation analysis in the country covering maternal mortality, pre-eclampsia occurrence, and existing government policy provisions for supplementation. We also consulted with experts and government officials to explore their perspectives and experience on supplementation. We then used AMSTAR (A MeaSurement Tool to Assess Systematic Reviews) to appraise the Cochrane Systematic Review of calcium supplementation. Finally, we used these data in a GRADE (Grading of Recommendations Assessment, Development and Evaluation)–Evidence to Decision framework to reach a policy recommendation.

Results

Our assessment of the Cochrane Review showed that the recommendation made by the WHO is based on weak evidence and trial findings that are not consistent between studies. The Cochrane Review found low certainty of the evidence for benefit (reduction in pre-eclampsia and maternal mortality). Conversely, there is a high certainty of the evidence of undesirable effects (HELLP [haemolysis, elevated liver enzymes and low platelets] syndrome) although this is uncommon. The likely absolute reduction in maternal deaths projected to Nepal was estimated to be low, while the implementation costs were high. Stakeholders also raised several concerns regarding feasibility, acceptability, appropriate dosing, and risk communication.

Conclusions

This review concludes that the blanket supplementation of calcium cannot be recommended in Nepal. A better approach may be to identify high-risk pregnant women and manage their antenatal visits and delivery to prevent mortality from pre-eclampsia.

Maternal and child nutrition in the Lives Saved Tool: Results of a recent update

Background

The Lives Saved Tool (LiST) is a mathematical modelling tool for estimating the survival, health, and nutritional impacts of scaling intervention coverage in low- and middle-income countries (LMICs). Various nutrition interventions are included in LiST and are regularly (and independently) reviewed and updated as new data emerge. This manuscript describes our latest in-depth review of nutrition evidence, focusing on intervention efficacy, appropriate population-affected fractions, and new interventions for potential inclusion in the LiST model.

Methods

An external advisory group (EAG) was assembled to review evidence from systematic reviews on intervention-outcome (I-O) pairs for women and children under five years of age. GRADE quality was assigned to each pair based on a LiST-specific checklist to facilitate consistent decisions during the consideration. For existing interventions with new information, the EAG was asked to recommend whether to update the default efficacy values and population-affected fractions. For the new interventions, the EAG decided whether there was sufficient evidence of benefit, and in affirmative cases, information on the efficacy and affected fraction values that could be used. Decisions were based on expert group consensus.

Results

Overall, the group reviewed 53 nutrition-related I-O pairs, including 25 existing and 28 new ones. Efficacy and population-affected fractions were updated for seven I-O pairs; three pairs were updated for efficacy estimates only, three were updated for population-affected fractions only; and nine new I-O pairs were added to the model, bringing the total of nutrition-related I-O pairs to 34. Included in the new I-O pairs were two new nutrition interventions added to LIST: zinc fortification and neonatal vitamin A supplementation.

Conclusions

For modelling tools like LiST to be useful, it is crucial to update interventions, efficacy and population-affected fractions as new evidence becomes available. The present updates will enable LiST users to better estimate the potential health, nutrition, and survival benefits of investing in nutrition.

Treatment for mild hypertension in pregnancy with different strategies: A systematic review and meta-analysis

OBJECTIVES

To synthesize the evidence from randomized controlled trials (RCTs) of antihypertensive treatment for mild pregnancy hypertension.

METHODS

We searched various databases from inception to June 2022, using keywords including hypertension; pregnancy; therapy; treatment; pregnancy outcomes; maternal outcomes; and perinatal outcomes. Only RCTs of antihypertensive treatment for mild hypertension in pregnancy comparing placebo/no therapy were included. We used Review Manager version 5.3 for statistical analyses.

RESULTS

In all, eight studies were eligible, with a total of 4211 participants. Compared with control, the active treatment significantly prevented preeclampsia (OR 0.55; 95%CI, 0.39-0.78), placental abruption (OR 0.39; 95%CI, 0.17-0.91), severe hypertension (OR 0.35; 95%CI, 0.17-0.71), end-organ dysfunction (OR 0.34; 95%CI, 0.19-0.62) and preterm birth (OR 0.69; 95%CI, 0.59-0.82), with no increased risk of small for gestational age (SGA) (OR 1.25; 95%CI, 0.78-2.00), or admission to the NICU (OR 0.83; 95%CI, 0.54-1.28). Subgroup analyses demonstrated that the tight control group did not show an advantage over the less-tight control group in improving pregnancy outcomes.

CONCLUSION

In pregnant women with mild pregnancy-induced hypertension or chronic hypertension, antihypertensive treatment still provided precise benefits of improving pregnancy outcomes without increased risk in fetal outcomes.

Associations Between Late-Onset Preeclampsia and the Use of Calcium-Based Antacids and Proton Pump Inhibitors During Pregnancy: A Prospective Cohort Study

Purpose

Preeclampsia is a leading cause of maternal morbidity and mortality. Calcium-based antacids and proton pump inhibitors (PPIs) are commonly used during pregnancy to treat symptoms of gastroesophageal reflux disease. Both have been hypothesized to reduce the risk of preeclampsia. We determined associations of calcium-based antacid and PPI use during pregnancy with late-onset preeclampsia (≥34 weeks of gestation), taking into account dosage and timing of use.

Patients and Methods

We included 9058 pregnant women participating in the PRIDE Study (2012–2019) or The Dutch Pregnancy Drug Register (2014–2019), two prospective cohorts in The Netherlands. Data were collected through web-based questionnaires and obstetric records. We estimated risk ratios (RRs) for late-onset preeclampsia for any use and trajectories of calcium-based antacid and PPI use before gestational day 238, and hazard ratios (HRs) for time-varying exposures after gestational day 237.

Results

Late-onset preeclampsia was diagnosed in 2.6% of pregnancies. Any use of calcium-based antacids (RR 1.2 [95% CI 0.9–1.6]) or PPIs (RR 1.4 [95% CI 0.8–2.4]) before gestational day 238 was not associated with late-onset preeclampsia. Use of low-dose calcium-based antacids in gestational weeks 0–16 (<1 g/day; RR 1.8 [95% CI 1.1–2.9]) and any use of PPIs in gestational weeks 17–33 (RR 1.6 [95% CI 1.0–2.8]) seemed to increase risks of late-onset preeclampsia. We did not observe associations between late-onset preeclampsia and use of calcium-based antacids (HR 1.0 [95% CI 0.6–1.5]) and PPIs (HR 1.4 [95% CI 0.7–2.9]) after gestational day 237.

Conclusion

In this prospective cohort study, use of calcium-based antacids and PPIs during pregnancy was not found to reduce the risk of late-onset preeclampsia.

Prevalence of Vitamin D and Calcium Deficiency and Insufficiency in Women of Childbearing Age and Associated Risk Factors: A Systematic Review and Meta-Analysis

Vitamin D deficiency and insufficiency as well as low serum calcium levels can trigger negative health outcomes in women of childbearing age. Therefore, we aimed to estimate the prevalence of serum vitamin D and calcium deficiencies and insufficiencies and associated risk factors in Brazilian women of childbearing age and to assess whether there are differences in prevalence according to regions of the country and the presence or absence of pregnancy. The systematic literature review was performed using the following databases: PubMed, LILACS, Embase, Scopus, and Web of Science. Cross-sectional, cohort, and intervention studies were included. Among pregnant women, the prevalence of vitamin D deficiency ranged from 0% to 27% and of vitamin D insufficiency from 33.9% to 70.4%. Among non-pregnant women, the prevalence of vitamin D deficiency ranged from 0% to 41.7% and of vitamin D insufficiency from 38.5% to 69.3%. We found a high prevalence of vitamin D deficiency and insufficiency in women of childbearing age, with insufficiency affecting more than half of these women. The highest prevalence of vitamin D deficiency and insufficiency was observed in the South region. It was not possible to assess the prevalence and factors associated with calcium deficiency.

Empirical evidence of study design biases in nutrition randomised controlled trials: a meta-epidemiological study

BACKGROUND

Instruments to critically appraise randomised controlled trials (RCTs) are based on evidence from meta-epidemiological studies. We aim to conduct a meta-epidemiological study on the average bias associated with reported methodological trial characteristics such as random sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and compliance of RCTs in nutrition research.

METHODS

We searched the Cochrane Database of Systematic Reviews, for systematic reviews of RCTs, published between 01 January 2010 and 31 December 2019. We combined the estimates of the average bias (e.g. ratio of risk ratios [RRR] or differences in standardised mean differences) in meta-analyses using the random-effects model. Subgroup analyses were conducted to investigate the potential differences among the RCTs with low versus high/unclear risk of bias with respect to the different types of interventions (e.g. micronutrients, fatty acids, dietary approach), outcomes (e.g. mortality, pregnancy outcomes), and type of outcome (objective, subjective). Heterogeneity was assessed through I² and τ², and prediction intervals were calculated.

RESULTS

We included 27 Cochrane nutrition reviews with 77 meta-analyses (n = 927 RCTs). The available evidence suggests that intervention effect estimates may not be exaggerated in RCTs with high/unclear risk of bias (versus low) judgement for sequence generation (RRR 0.97, 95% CI 0.93 to 1.02; I² = 28%; τ² = 0.002), allocation concealment (RRR 1.00, 95% CI 0.96 to 1.04; I² = 27%; τ² = 0.001), blinding of participants and personnel (RRR 0.95, 95% CI 0.91 to 1.00; I² = 23%; τ² = 0), selective reporting (RRR 0.97, 95% CI 0.92 to 1.02; I² = 24%; τ² = 0), and compliance (RRR 0.95, 95% CI 0.89 to 1.02; I² = 0%; τ² = 0). Intervention effect estimates seemed to be exaggerated in RCTs with a high/unclear risk of bias judgement for blinding of outcome assessment (RRR 0.81, 95% CI 0.70 to 0.94; I² = 26%; τ² = 0.03), which was predominately driven by subjective outcomes, and incomplete outcome data (RRR 0.92, 95% CI 0.88 to 0.97; I² = 22%; τ² = 0.001). For continuous outcomes, no differences were observed, except for selective reporting.

CONCLUSIONS

On average, most characteristics of nutrition RCTs may not exaggerate intervention effect estimates, but the average bias appears to be greatest in trials of subjective outcomes. Replication of this study is suggested in this field to keep this conclusion updated.

Scaling up prenatal nutrition could reduce the global burden of noncommunicable diseases in the next generation: a modeling analysis

BACKGROUND

Nutritional conditions during pregnancy may influence the epigenetic development of an individual and consequently their later-life risk of noncommunicable disease (NCD). Improving nutrition for pregnant females may therefore serve the dual purpose of directly improving pregnancy outcomes and preventing NCDs in the next generation.

OBJECTIVES

We estimated the impact of prenatal supplementation with iron and folic acid (IFA), multiple micronutrients (MMS), or calcium at 50%, 75%, or 90% coverage on future NCDs by age and sex in 2015.

METHODS

We used secondary data sources from 132 countries to quantify the cases of diabetes and hypertension and the deaths from selected NCDs that could be averted or delayed by scaling up prenatal micronutrient supplementation.

RESULTS

Globally, >51,000 NCD deaths, 6 million cases of hypertension, and 3 million cases of diabetes could be prevented per offspring birth cohort if mothers were prenatally supplemented with MMS at 90% coverage. For IFA these numbers would be roughly half. Calcium supplementation at 90% could delay 51,000 deaths per birth cohort. Our model suggests that substantial numbers of NCD deaths and cases of hypertension and diabetes could be prevented in future generations by scaling up micronutrient supplementation for mothers during pregnancy.

CONCLUSIONS

Highlighting the additional benefits of proven nutrition interventions is critical in ensuring adequate and sustained investments, and programmatic integration. As the double burden of disease continues to grow, population-wide efforts to scale up micronutrient supplementation to pregnant females could help prevent both undernutrition and chronic disease.

Reviewing Accuracy of First Trimester Screening for Preeclampsia Using Maternal Factors and Biomarkers

Preeclampsia is a common and important complication of pregnancy, one with potentially significant morbidity and even mortality to both mother and baby. Identifying those at high risk of developing the condition is helpful as there is evidence that the incidence of preeclampsia can be reduced with low dose aspirin taken in pregnancy. Accurately predicting the risk of preeclampsia allows for more targeted aspirin prophylaxis and a greater opportunity for early detection of maternal and/or fetal complications associated with impaired placentation through a schedule of enhanced antenatal surveillance. Traditional preeclampsia prediction models use maternal characteristics and risk factors and have been shown to be of low predictive value. Multiparametric screening tests combine patient characteristics with serum biomarkers and ultrasound Doppler indices and have been shown to be more effective at detecting those at high risk of preeclampsia – more specifically, early-onset preeclampsia (onset of preeclampsia <34 weeks’ gestation). Multiparametric screening has now been validated in different populations. The true cost effectiveness of a multiparametric screening model for preeclampsia screening is not yet fully known and will vary depending on the clinical setting. Despite the growing body of evidence for its improved detection rates, first trimester preeclampsia screening using multiparametric models is not widely implemented and is not part of the recommendations for antenatal screening from most international bodies. The International Federation of Gynecology and Obstetrics has advised universal preeclampsia screening using maternal risk factors and biomarkers and has strongly encouraged its promotion worldwide. Various barriers to implementation must be considered such as the immediate cost of equipment and training, the need for audit and quality control, and the expected benefit to the population. Low to middle income settings may require a pragmatic approach to the implementation of multiparametric screening given limited resources.

Diagnostic biomolecules and combination therapy for pre-eclampsia

Pre-eclampsia (PE), associated with placental malperfusion, is the primary reason for maternal and perinatal mortality and morbidity that can cause vascular endothelial injury and multi-organ injury. Despite considerable research efforts, no pharmaceutical has been shown to stop disease progression. If women precisely diagnosed with PE can achieve treatment at early gestation, the maternal and fetal outcomes can be maximally optimized by expectant management. Current diagnostic approaches applying maternal characteristics or biophysical markers, including blood test, urine analysis and biophysical profile, possess limitations in the precise diagnosis of PE. Biochemical factor research associated with PE development has generated ambitious diagnostic targets based on PE pathogenesis and dissecting molecular phenotypes. This review focuses on current developments in biochemical prediction of PE and the corresponding interventions to ameliorate disease progression, aiming to provide references for clinical diagnoses and treatments.

Maternal nutritional risk factors for pre-eclampsia incidence: findings from a narrative scoping review

BACKGROUND

Pre-eclampsia is a leading cause of maternal mortality and morbidity that involves pregnancy-related stressors on the maternal cardiovascular and metabolic systems. As nutrition is important to support optimal development of the placenta and for the developing fetus, maternal diets may play a role in preventing pre-eclampsia. The purpose of this scoping review is to map the maternal nutritional deficiencies and imbalances associated with pre-eclampsia incidence and discuss evidence consistency and linkages with current understandings of the etiology of pre-eclampsia.

METHODS

A narrative scoping review was conducted to provide a descriptive account of available research, summarize research findings and identify gaps in the evidence base. Relevant observational studies and reviews of observational studies were identified in an iterative two-stage process first involving electronic database searches then more sensitive searches as familiarity with the literature increased. Results were considered in terms of their consistency of evidence, effect sizes and biological plausibility.

RESULTS

The review found evidence for associations between nutritional inadequacies and a greater risk of pre-eclampsia. These associations were most likely mediated through oxidative stress, inflammation, maternal endothelial dysfunction and blood pressure in the pathophysiology of pre-eclampsia. Maternal nutritional risk factors for pre-eclampsia incidence with the strongest consistency, effect and biological plausibility include vitamin C and its potential relationship with iron status, vitamin D (both on its own and combined with calcium and magnesium), and healthy dietary patterns featuring high consumption of fruits, vegetables, whole grains, fish, seafood and monounsaturated vegetable oils. Foods high in added sugar, such as sugary drinks, were associated with increased risk of pre-eclampsia incidence.

CONCLUSION

A growing body of literature highlights the involvement of maternal dietary factors in the development of pre-eclampsia. Our review findings support the need for further investigation into potential interactions between dietary factors and consideration of nutritional homeostasis and healthy dietary patterns. Further research is recommended to explore gestational age, potential non-linear relationships, dietary diversity and social, cultural contexts of food and meals.

Impact of vitamin D on maternal and fetal health: A review

The role of vitamin D in improving maternal health and reducing the risk of developmental disorders in fetus has been an important domain of research since the past few years. Vitamin D, owing to its immunomodulatory, anti‐inflammatory, developmental roles, and regulating calcium homeostasis, is predicted to have a significant influence on maternal and fetal health status. Several observational studies and clinical trials, determining the impact of vitamin D on gestational diabetes, C‐section, postpartum depression, pre‐eclampsia, miscarriages, and preterm delivery, have been elaborated in this review. In addition, fetal birth defects including neurological development, reduced birth weight, respiratory infections, bone development, and altered anthropometrics have also been summarized with available evidences. Other important mechanisms related to the roles of vitamin D in the body are also explained. Furthermore, recent studies determining the effect of vitamin D at genetic level will also help in understanding and future design of research in the area of maternal and fetal health.

Medications for preventing hypertensive disorders in high-risk pregnant women: a systematic review and network meta-analysis

OBJECTIVES

To determine the relative effectiveness of medications for preventing hypertensive disorders in high-risk pregnant women and to provide a ranking of medications using network meta-analysis.

METHODS

All randomized controlled trials comparing the most commonly used medications to prevent hypertensive disorders in high-risk pregnant women that are nulliparity and pregnant women having family history of preeclampsia, history of pregnancy-induced hypertension in previous pregnancy, obstetric risks, or underlying medical diseases. We received the search results from the Cochrane Pregnancy and Childbirth's Specialised Register of Controlled Trials, searched on 31st July 2020. At least two review authors independently selected the included studies and extracted the data and the methodological quality. The comparative risk ratios (RR) and 95% confidence intervals (CI) were analyzed using pairwise and network meta-analyses, and treatment rankings were estimated by the surface under the cumulative ranking curve for preventing preeclampsia (PE), gestational hypertension (GHT), and superimposed preeclampsia (SPE). Safety of the medications is also important for decision-making along with effectiveness which will be reported in a separate review.

RESULTS

This network meta-analysis included 83 randomized studies, involving 93,864 women across global regions. Three medications, either alone or in combination, probably prevented PE in high-risk pregnant women when compared with a placebo or no treatment from network analysis: antiplatelet agents with calcium (RR 0.19, 95% CI 0.04 to 0.86; 1 study; low-quality evidence), calcium (RR 0.61, 95% CI 0.47 to 0.80; 13 studies; moderate-quality evidence), antiplatelet agents (RR 0.69, 95% CI 0.57 to 0.82; 31 studies; moderate-quality evidence), and antioxidants (RR 0.77, 95% CI 0.63 to 0.93; 25 studies; moderate-quality evidence). Calcium probably prevented PE (RR 0.63, 95% CI 0.46 to 0.86; 11 studies; moderate-quality evidence) and GHT (RR 0.89, 95% CI 0.84 to 0.95; 8 studies; high-quality evidence) in nulliparous/primigravida women. Few included studies for the outcome of superimposed preeclampsia were found.

CONCLUSION

Antiplatelet agents, calcium, and their combinations were most effective medications for preventing hypertensive disorders in high-risk pregnant women when compared with a placebo or no treatment. Any high-risk characteristics for women are important in deciding the best medications. The qualities of evidence were mostly rated to be moderate.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018096276.

Interventions for the prevention of spontaneous preterm birth: a scoping review of systematic reviews

BACKGROUND

Globally, 11% of babies are born preterm each year. Preterm birth (PTB) is a leading cause of neonatal death and under-five mortality and morbidity, with lifelong sequelae in those who survive. PTB disproportionately impacts low/middle-income countries (LMICs) where the burden is highest.

OBJECTIVES

This scoping review sought to the evidence for interventions that reduce the risk of PTB, focusing on the evidence from LMICs and describing how context is considered in evidence synthesis.

DESIGN

We conducted a scoping review, to describe this wide topic area. We searched five electronic databases (2009-2020) and contacted experts to identify relevant systematic reviews of interventions to reduce the risk of PTB. We included published systematic reviews that examined the effectiveness of interventions and their effect on reducing the risk of PTB. Data were extracted and is described narratively.

RESULTS

139 published systematic reviews were included in the review. Interventions were categorised as primary or secondary. The interventions where the results showed a greater effect size and consistency across review findings included treatment of syphilis and vaginal candidiasis, vitamin D supplementation and cervical cerclage. Included in the 139 reviews were 1372 unique primary source studies. 28% primary studies were undertaken in LMIC contexts and only 4.5% undertaken in a low-income country (LIC) Only 10.8% of the reviews sought to explore the impact of context on findings, and 19.4% reviews did not report the settings or the primary studies.

CONCLUSION

This scoping review highlights the lack of research evidence derived from contexts where the burden of PTB globally is greatest. The lack of rigour in addressing contextual applicability within systematic review methods is also highlighted. This presents a risk of inappropriate and unsafe recommendations for practice within these contexts. It also highlights a need for primary research, developing and testing interventions in LIC settings.

Validation of maternal report of nutrition-related interventions and counselling during antenatal care in southern Nepal

The delivery of nutrition-related interventions and counselling during antenatal care is critical for a healthy pregnancy for both mother and child. However, the accuracy of maternal reports of many of these services during household surveys has not yet been examined. Our objectives were to assess the validity of the maternal reports of 10 antenatal nutrition interventions, including counselling, and examine associates between maternal characteristics and accuracy. Maternal report of services received collected during a post-partum survey was compared to the gold standard, the direct observation of all women's antenatal care visits. Individual-level validity was assessed by calculating indicator sensitivity, specificity and area under the operating curve (AUC). The inflation factor (IF) measured population-level bias. For five indicators, the high true coverage limited our ability to assess the validity of the maternal reports. There were no indicators that had both high individual-level validity (AUC > 0.70) and low population bias (0.75 < IF < 1.25). Indicators with greater true coverage estimates had higher sensitivity and lower specificity estimates compared to those indicators with lower true coverage. There were no maternal characteristics associated with the accuracy of the report. Maternal report of antenatal nutrition-related interventions and counselling during household surveys was found to have variable validity across indicators. Additional research in settings with varying coverage levels should be considered to best inform antenatal care coverage measurement in household surveys.

Population attributable fractions for risk factors for spontaneous preterm births in 81 low- and middle-income countries: A systematic analysis

Background

Complications associated with preterm birth (PTB) are the largest contributor to under-five mortality globally. Success in reaching the Sustainable Development Goal target requires identifying potentially modifiable risk factors for PTB, estimating the relative importance of these risk factors, and identifying/implementing effective prevention strategies to address them.

Methods

We conducted a literature review to define risk relationships and estimate prevalence for established risk factors for spontaneous PTB (sPTB). We then estimated population attributable fractions (PAF) for the sPTB risk factors identified in the review as statistically significant for the 81 low- and middle-income (LMIC) countries included in the Countdown 2030 initiative. We summed country-level findings to produce PAFs for each risk factor and regional estimates for sub-Saharan Africa and South Asia.

Results

Forty-four potential sPTB risk factors were identified. and the final analysis included twenty-four risk factors with evidence of significant associations with sPTB. A second model with three additional risk factors with borderline insignificant associations was also run. Taken together, the twenty-four risk factors had a total PAF of 73% for all 81 countries and 77% and 72% of sPTB in sub-Saharan Africa and South Asia, respectively. For all countries, maternal undernutrition had the highest PAF (17.5%), followed by maternal infections (16.6%), environmental exposures (16%) and pregnancy history (8.7%).

Conclusions

While multiple risk factors contribute to sPTB, no single risk factor addresses a predominant fraction, and 27% of spontaneous preterm births are not associated with risk factors that we identified. Despite the significant role of preterm birth in child survival, there are major data gaps in LMIC settings. Furthermore, there is a paucity of evidence for effective interventions to prevent preterm birth. Preventing sPTB requires understanding underlying mechanisms leading to sPTB in different populations, and the identification/implementation of effective interventions.

Tocotrienol in Pre-Eclampsia Prevention: A Mechanistic Analysis in Relation to the Pathophysiological Framework

The pathophysiology of pre-eclampsia involves two major pathways, namely systemic oxidative stress and subsequent generalised inflammatory response, which eventually culminates in endothelial cell injury and the syndrome of pre-eclampsia with multi-organ dysfunction. Aspirin has been used to reduce the risk of pre-eclampsia, but it only possesses anti-inflammatory properties without any antioxidant effect. Hence, it can only partially alleviate the problem. Tocotrienols are a unique form of vitamin E with strong antioxidant and anti-inflammatory properties that can be exploited as a preventive agent for pre-eclampsia. Many preclinical models showed that tocotrienol can also prevent hypertension and ischaemic/reperfusion injury, which are the two main features in pre-eclampsia. This review explores the mechanism of action of tocotrienol in relation to the pathophysiology of pre-eclampsia. In conclusion, the study provides sufficient justification for the establishment of a large clinical trial to thoroughly assess the capability of tocotrienol in preventing pre-eclampsia.

Toward personalized management of chronic hypertension in pregnancy

Chronic hypertension complicates 1% to 2% of pregnancies, and it is increasingly common. Women with chronic hypertension are an easily recognized group who are in touch with a wide variety of healthcare providers before, during, and after pregnancy, mandating that chronic hypertension in pregnancy be within the scope of many practitioners. We reviewed recent data on management to inform current care and future research. This study is a narrative review of published literature. Compared with normotensive women, women with chronic hypertension are at an increased risk of maternal and perinatal complications. Women with chronic hypertension who wish to be involved in their care can do by measuring blood pressure at home. Accurate devices for home blood pressure monitoring are now readily available. The diagnostic criteria for superimposed preeclampsia remain problematic because most guidelines continue to include deteriorating blood pressure control in the definition. It has not been established how angiogenic markers may aid in confirmation of the diagnosis of superimposed preeclampsia when suspected, over and above information provided by routinely available clinical data and laboratory results. Although chronic hypertension is a strong risk factor for preeclampsia, and aspirin decreases preeclampsia risk, the effectiveness specifically among women with chronic hypertension has been questioned. It is unclear whether calcium has an independent effect in preeclampsia prevention in such women. Treating hypertension with antihypertensive therapy halves the risk of progression to severe hypertension, thrombocytopenia, and elevated liver enzymes, but a reduction in preeclampsia or serious maternal complications has not been observed; however, the lack of evidence for the latter is possibly owing to few events. In addition, treating chronic hypertension neither reduces nor increases fetal or newborn death or morbidity, regardless of the gestational age at which the antihypertensive treatment is started. Antihypertensive agents are not teratogenic, but there may be an increase in malformations associated with chronic hypertension itself. At present, blood pressure treatment targets used in clinics are the same as those used at home, although blood pressure values tend to be inconsistently lower at home among women with hypertension. Although starting all women on the same antihypertensive medication is usually effective in reducing blood pressure, it remains unclear whether there is an optimal agent for such an approach or how best to use combinations of antihypertensive medications. An alternative approach is to individualize care, using maternal characteristics and blood pressure features beyond blood pressure level (eg, variability) that are of prognostic value. Outcomes may be improved by timed birth between 38 0/7 and 39 6/7 weeks' gestation based on observational literature; of note, confirmatory trial evidence is pending. Postnatal care is facilitated by the acceptability of most antihypertensives (including angiotensin-converting enzymes inhibitors) for use in breastfeeding. The evidence base to guide the care of pregnant women with chronic hypertension is growing and aligning with international guidelines. Addressing outstanding research questions would inform personalized care of chronic hypertension in pregnancy.

Different Doses of Calcium Supplementation to Prevent Gestational Hypertension and Pre-Eclampsia: A Systematic Review and Network Meta-Analysis

Objective

Calcium supplementation can prevent gestational hypertension and pre-eclampsia. However, besides the non-consensus of existing studies, there is a lack of evidence regarding the optimal dosing of calcium.

Method

Eight electronic databases, namely, the Cochrane Library, PUBMED, Web of Science, EMBASE, WANGFANG, VIP, CBM, and CNKI, were searched. The studies were retrieved from inception to July 13, 2021. Two researchers independently screened the literature, extracted data, and evaluated the methodological quality based on the inclusion criteria. In particular, the calcium supplementation doses were divided into three groups, namely, the high-dose (≥1.5 g), medium-dose (1.0–1.49 g), and the low-dose group (<1.0 g). The participants were also divided into high-risk and low-risk groups, according to the risk of developing gestational hypertension and pre-eclampsia.

Results and Discussion

A total of 48 studies were incorporated into the final analyses. All doses of calcium supplementation reduced the incidence of gestational hypertension in the low-risk population (low dose - three studies; medium dose- 11 studies; high dose- 28 studies), whereas the medium-dose (three studies) reduced the incidence of gestational hypertension in high-risk groups. Moreover, a medium dose of calcium supplementation had the maximum effect in reducing gestational hypertension in low-risk and high-risk populations. The medium (three studies) and high doses (13 studies) of calcium supplementation reduced the incidence of pre-eclampsia in the low-risk groups. However, a medium-dose calcium supplementation maximally prevented pre-eclampsia in the low-risk population. The authenticity and reliability of the results were reduced due to the limitations of contemporary studies in terms of experimental design, result measurement, statistics, and evidence quality. Therefore, high-quality studies with larger sample size are required to evaluate further the effect of calcium supplementation in preventing gestational hypertension and pre-eclampsia.