Vitamin C supplementation in pregnancy

Role of Vitamin C Supplementation in the Prevention of Premature Rupture of Membranes (PROM) and Preterm PROM: A Systematic Review and Meta-Analysis

Vitamin C is a micronutrient assumed to have effects on the occurrence of "preterm premature rupture of membranes" (PPROM) and "premature rupture of membranes" (PROM). The objective of this review was to find the pooled incidence of PROM and/or PPROM between subgroups in relation to dose, mode of therapy (monotherapy vs. combination therapy) and history of PROM/PPROM in previous pregnancies. A search was conducted in the electronic databases (PubMed, Google Scholar, Scopus) from inception to November 2022, using the search terms "Vitamin C", "Ascorbic acid", "preterm premature rupture of membrane" and "premature rupture of membrane". The lists of references of all the selected eligible articles were also searched to find studies of interest. A total of nine randomized controlled trials (published in English) with 16,076 participants involving the supplementation of vitamin C during pregnancy were picked up for analysis. Data management was done using the Review Manager (RevMan 5.3). A statistical test for publication bias was done in jamovi, version 2.3.18. In comparison to placebo, vitamin C supplementation was not found to be significantly effective in preventing the occurrence of PPROM/PROM. However, a low dose of vitamin C and the monotherapy mode of administration significantly decreased the occurrence of PPROM/PROM. Vitamin C has significant beneficial effects in women with a history of PROM in a previous pregnancy. Hence, we conclude that vitamin C administered as monotherapy in low doses (preferably 100 mg/day) has definite benefits in preventing the occurrence of PROM/PPROM with greater advantages seen in those with a history of similar complications in a previous pregnancy.

Nutrient Requirements during Pregnancy and Lactation

A woman's nutritional status during pregnancy and breastfeeding is not only critical for her health, but also for that of future generations. Nutritional requirements during pregnancy differ considerably from those of non-pregnant women. Thus, a personalized approach to nutritional advice is recommended. Currently, some countries recommend routine supplementation for all pregnant women, while others recommend supplements only when necessary. Maternal physiological adaptations, as well as nutritional requirements during pregnancy and lactation, will be reviewed in the literature examining the impacts of dietary changes. All of these data have been studied deeply to facilitate a discussion on dietary supplement use and the recommended doses of nutrients during pregnancy and lactation. The aim of this review is to evaluate the knowledge in the scientific literature on the current recommendations for the intake of the most common micronutrients and omega-3 fatty acids during pregnancy and lactation in the United States, Canada, and Europe. Taking into account these considerations, we examine minerals, vitamins, and omega-3 fatty acid requirements. Finally, we conclude by discussing the potential benefits of each form of supplementation.

COVID-19 Treatment: Drug Safety Prior to Conception and During Pregnancy and Breastfeeding

In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.

Maternal N-Acetyl Cysteine Intake Improved Glucose Tolerance in Obese Mice Offspring

Exposure to certain environmental factors during the early stages of development was found to affect health in adulthood. Among other environmental factors, oxidative stress has been suggested to be involved in fetal programming, leading to elevated risk for metabolic disorders, including type 2 diabetes; however, the possibility that antioxidant consumption during early life may affect the development of diabetes has scarcely been studied. The aim of this study was to investigate the effects of N-acetyl-l-cysteine (NAC) given during pregnancy and lactation on the susceptibility of offspring to develop glucose intolerance at adulthood. C57bl6/J mice were given NAC during pregnancy and lactation. High fat diet (HFD) was given to offspring at an age of 6 weeks for an additional 9 weeks, till the end of the study. Isolated islets of NAC-treated offspring (6 weeks old, before HFD feeding) had an increased efficacy of glucose-stimulated insulin secretion and a higher resistance to oxidative damage. Following HFD feeding, glucose tolerance and insulin sensitivity of NAC-treated offspring were improved. In addition, islet diameter was lower in male offspring of NAC-treated mice compared to their HFD-fed littermates. NAC consumption during early life improves glucose tolerance in adulthood in mice.

Micromass Methods for the Evaluation of Developmental Toxicants

Chick embryonic heart has recently been utilized as a model to create a micromass (MM) culturing system. The aim was to overcome the ethical barriers arising from testing the embryotoxicity of chemicals using human embryonic cells. The system represents a valuable tool to study the ability of chemicals to interfere with various embryonic developmental processes such as cellular communication, differentiation, cellular activity, and proliferation, where the disturbance any of them could result in maldevelopment. The system can also be utilized to investigate ROS production and expression of several transmembrane proteins to study their roles in chemical-induced teratogenicity or embryotoxicity.

Association between Vitamin Intake during Pregnancy and Risk of Small for Gestational Age

Pregnancy increases the requirements of certain nutrients, such as vitamins, to provide nutrition for the newborn. The aim was to analyze the association between dietary intake of vitamins during pregnancy and risk of having a small for gestational age (SGA) newborn. A matched case-control study was conducted (518 cases and 518 controls of pregnant women) in Spain. Dietary vitamin intake during pregnancy was assessed using a validated food frequency questionnaire, categorized into quintiles. Odds ratios (ORs) and their 95% confidence intervals (CI) were estimated with conditional regression logistic models. A protective association was observed between maternal dietary intake of vitamins A and D and SGA. For vitamin B3 and B6, the observed protective effect was maintained after adjusting for potential confounding factors. For vitamin B9, we found only an effect in quintiles 3 and 4 (OR = 0.64; 95% CI, 0.41-1.00; OR = 0.58; 95% CI, 0.37-0.91). Protective effect for vitamin B12 was observed in 4th and 5th quintiles (OR = 0.61; 95% CI, 0.39-0.95; OR = 0.68; 95% CI, 0.43-1.04). No associations were detected between dietary intake of vitamins B2, E and C intake and SGA. Our results suggest a positive association between dietary vitamin intake during pregnancy and the weight of the newborn, although more studies are necessary and there could be a ceiling effect for higher intakes of some vitamins cannot be discarded.

Vitamin C to Decrease the Effects of Smoking in Pregnancy on Infant Lung Function (VCSIP): Rationale, design, and methods of a randomized, controlled trial of vitamin C supplementation in pregnancy for the primary prevention of effects of in utero tobacco smoke exposure on infant lung function and respiratory health

Despite strong anti-smoking efforts, at least 12% of American women cannot quit smoking when pregnant resulting in >450,000 smoke-exposed infants born yearly. Smoking during pregnancy is the largest preventable cause of childhood respiratory illness including wheezing and asthma. Recent studies have shown a protective effect of vitamin C supplementation on the lung function of offspring exposed to in utero smoke in a non-human primate model and an initial human trial. Vitamin C to Decrease the Effects of Smoking in Pregnancy on Infant Lung Function (VCSIP) is a randomized, double-blind, placebo-controlled trial to evaluate pulmonary function at 3months of age in infants delivered to pregnant smokers randomized to 500mg/day of vitamin C versus placebo during pregnancy. Secondary aims evaluate the incidence of wheezing through 12months and pulmonary function testing at 12months of age. Women are randomized between 13 and 23weeks gestation from clinical sites in Portland, Oregon at Oregon Health & Science University and PeaceHealth Southwest Medical Center and in Indianapolis, Indiana at Indiana University and Wishard Hospital. Vitamin C supplementation occurs from randomization to delivery. Monthly contact with participants and monitoring of medical records is performed to document medication adherence, changes in smoking and medical history, and adverse events. Pulmonary function testing of offspring occurs at 3 and 12months of age and incidence of wheezing and respiratory illness through 12months is captured via at least quarterly questionnaires. Ancillary studies are investigating the impact of vitamin C on placental blood flow and DNA methylation.

α-Tocopherol and Hippocampal Neural Plasticity in Physiological and Pathological Conditions

Neuroplasticity is an "umbrella term" referring to the complex, multifaceted physiological processes that mediate the ongoing structural and functional modifications occurring, at various time- and size-scales, in the ever-changing immature and adult brain, and that represent the basis for fundamental neurocognitive behavioral functions; in addition, maladaptive neuroplasticity plays a role in the pathophysiology of neuropsychiatric dysfunctions. Experiential cues and several endogenous and exogenous factors can regulate neuroplasticity; among these, vitamin E, and in particular α-tocopherol (α-T), the isoform with highest bioactivity, exerts potent effects on many plasticity-related events in both the physiological and pathological brain. In this review, the role of vitamin E/α-T in regulating diverse aspects of neuroplasticity is analyzed and discussed, focusing on the hippocampus, a brain structure that remains highly plastic throughout the lifespan and is involved in cognitive functions. Vitamin E-mediated influences on hippocampal synaptic plasticity and related cognitive behavior, on post-natal development and adult hippocampal neurogenesis, as well as on cellular and molecular disruptions in kainate-induced temporal seizures are described. Besides underscoring the relevance of its antioxidant properties, non-antioxidant functions of vitamin E/α-T, mainly involving regulation of cell signaling molecules and their target proteins, have been highlighted to help interpret the possible mechanisms underlying the effects on neuroplasticity.

Low Serum Vitamin C Status Among Pregnant Women Attending Antenatal Care at General Hospital Dawakin Kudu, Northwest Nigeria

Background:

Vitamin C levels are low in pregnancy. The purpose of this study was to determine serum Vitamins C levels among pregnant women attending antenatal care at a General Hospital in Dawakin Kudu, Kano, and this can help further research to determine the place of Vitamin C supplementation in pregnancy.

Methods:

This was a prospective study of 400 pregnant women who presented for antenatal care in General Hospital Dawakin Kudu, Kano, Nigeria. Research structured questionnaire was administered to 400 respondents. Determination of serum Vitamin C was done using appropriate biochemical methods.

Results:

Vitamin C deficiency was found in 79.5% of the participants. The values for Vitamin C were 0.20 ± 0.18 mg/dl during the first trimester, 0.50 ± 0.99 mg/dl in the second trimester, and 0.35 ± 0.36 mg/dl in the third trimester and P = 0.001.

Conclusions:

There is a significant reduction in the serum Vitamins C concentration throughout the period of pregnancy with the highest levels in the second trimester. Therefore, Vitamin C supplementation is suggested during pregnancy, especially for those whose fruit and vegetable consumption is inadequate.

Developmental aspects of a life course approach to healthy ageing

We examine the mechanistic basis and wider implications of adopting a developmental perspective on human ageing. Previous models of ageing have concentrated on its genetic basis, or the detrimental effects of accumulated damage, but also have raised issues about whether ageing can be viewed as adaptive itself, or is a consequence of other adaptive processes, for example if maintenance and repair processes in the period up to reproduction are traded off against later decline in function. A life course model places ageing in the context of the attainment of peak capacity for a body system, starting in early development when plasticity permits changes in structure and function induced by a range of environmental stimuli, followed by a period of decline, the rate of which depends on the peak attained as well as the later life conditions. Such path dependency in the rate of ageing may offer new insights into its modification. Focusing on musculoskeletal and cardiovascular function, we discuss this model and the possible underlying mechanisms, including endothelial function, oxidative stress, stem cells and nutritional factors such as vitamin D status. Epigenetic changes induced during developmental plasticity, and immune function may provide a common mechanistic process underlying a life course model of ageing. The life course trajectory differs in high and low resource settings. New insights into the developmental components of the life course model of ageing may lead to the design of biomarkers of later chronic disease risk and to new interventions to promote healthy ageing, with important implications for public health.

Vitamin C supplementation in pregnancy

BACKGROUND

Vitamin C supplementation may help reduce the risk of pregnancy complications such as pre-eclampsia, intrauterine growth restriction and maternal anaemia. There is a need to evaluate the efficacy and safety of vitamin C supplementation in pregnancy.

OBJECTIVES

To evaluate the effects of vitamin C supplementation, alone or in combination with other separate supplements on pregnancy outcomes, adverse events, side effects and use of health resources.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials evaluating vitamin C supplementation in pregnant women. Interventions using a multivitamin supplement containing vitamin C or where the primary supplement was iron were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

Twenty-nine trials involving 24,300 women are included in this review. Overall, 11 trials were judged to be of low risk of bias, eight were high risk of bias and for 10 trials it was unclear. No clear differences were seen between women supplemented with vitamin C alone or in combination with other supplements compared with placebo or no control for the risk of stillbirth (risk ratio (RR) 1.15, 95% confidence intervals (CI) 0.89 to 1.49; 20,038 participants; 11 studies; I² = 0%; moderate quality evidence), neonatal death (RR 0.79, 95% CI 0.58 to 1.08; 19,575 participants; 11 studies; I² = 0%), perinatal death (average RR 1.07, 95% CI 0.77 to 1.49; 17,105 participants; seven studies; I² = 35%), birthweight (mean difference (MD) 26.88 g, 95% CI -18.81 to 72.58; 17,326 participants; 13 studies; I² = 69%), intrauterine growth restriction (RR 0.98, 95% CI 0.91 to 1.06; 20,361 participants; 12 studies; I² = 15%; high quality evidence), preterm birth (average RR 0.99, 95% CI 0.90 to 1.10; 22,250 participants; 16 studies; I² = 49%; high quality evidence), preterm PROM (prelabour rupture of membranes) (average RR 0.98, 95% CI 0.70 to 1.36; 16,825 participants; 10 studies; I² = 70%; low quality evidence), term PROM (average RR 1.26, 95% CI 0.62 to 2.56; 2674 participants; three studies; I² = 87%), and clinical pre-eclampsia (average RR 0.92, 95% CI 0.80 to 1.05; 21,956 participants; 16 studies; I² = 41%; high quality evidence).Women supplemented with vitamin C alone or in combination with other supplements compared with placebo or no control were at decreased risk of having a placental abruption (RR 0.64, 95% CI 0.44 to 0.92; 15,755 participants; eight studies; I² = 0%; high quality evidence) and had a small increase in gestational age at birth (MD 0.31, 95% CI 0.01 to 0.61; 14,062 participants; nine studies; I² = 65%), however they were also more likely to self-report abdominal pain (RR 1.66, 95% CI 1.16 to 2.37; 1877 participants; one study). In the subgroup analyses based on the type of supplement, vitamin C supplementation alone was associated with a reduced risk of preterm PROM (average RR 0.66, 95% CI 0.48 to 0.91; 1282 participants; five studies; I² = 0%) and term PROM (average RR 0.55, 95% CI 0.32 to 0.94; 170 participants; one study). Conversely, the risk of term PROM was increased when supplementation included vitamin C and vitamin E (average RR 1.73, 95% CI 1.34 to 2.23; 3060 participants; two studies; I² = 0%). There were no differences in the effects of vitamin C on other outcomes in the subgroup analyses examining the type of supplement. There were no differing patterns in other subgroups of women based on underlying risk of pregnancy complications, timing of commencement of supplementation or dietary intake of vitamin C prior to trial entry. The GRADE quality of the evidence was high for intrauterine growth restriction, preterm birth, and placental abruption, moderate for stillbirth and clinical pre-eclampsia, low for preterm PROM.

AUTHORS' CONCLUSIONS

The data do not support routine vitamin C supplementation alone or in combination with other supplements for the prevention of fetal or neonatal death, poor fetal growth, preterm birth or pre-eclampsia. Further research is required to elucidate the possible role of vitamin C in the prevention of placental abruption and prelabour rupture of membranes. There was no convincing evidence that vitamin C supplementation alone or in combination with other supplements results in other important benefits or harms.

Vitamin E supplementation in pregnancy

BACKGROUND

Vitamin E supplementation may help reduce the risk of pregnancy complications involving oxidative stress, such as pre-eclampsia. There is a need to evaluate the efficacy and safety of vitamin E supplementation in pregnancy.

OBJECTIVES

To assess the effects of vitamin E supplementation, alone or in combination with other separate supplements, on pregnancy outcomes, adverse events, side effects and use of health services.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 March 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials evaluating vitamin E supplementation in pregnant women. We excluded interventions using a multivitamin supplement that contained vitamin E.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

Twenty-one trials, involving 22,129 women were eligible for this review. Four trials did not contribute data. All of the remaining 17 trials assessed vitamin E in combination with vitamin C and/or other agents. Overall the risk of bias ranged from low to unclear to high; 10 trials were judged to be at low risk of bias, six trials to be at unclear risk of bias and five trials to be at high risk of bias. No clear difference was found between women supplemented with vitamin E in combination with other supplements during pregnancy compared with placebo for the risk of stillbirth (risk ratio (RR) 1.17, 95% confidence interval (CI) 0.88 to 1.56, nine studies, 19,023 participants, I² = 0%; moderate quality evidence), neonatal death (RR 0.81, 95% CI 0.58 to 1.13, nine trials, 18,617 participants, I² = 0%), pre-eclampsia (average RR 0.91, 95% CI 0.79 to 1.06; 14 trials, 20,878 participants; I² = 48%; moderate quality evidence), preterm birth (average RR 0.98, 95% CI 0.88 to 1.09, 11 trials, 20,565 participants, I² = 52%; high quality evidence) or intrauterine growth restriction (RR 0.98, 95% CI 0.91 to 1.06, 11 trials, 20,202 participants, I² = 17%; high quality evidence). Women supplemented with vitamin E in combination with other supplements compared with placebo were at decreased risk of having a placental abruption (RR 0.64, 95% CI 0.44 to 0.93, seven trials, 14,922 participants, I² = 0%; high quality evidence). Conversely, supplementation with vitamin E was associated with an increased risk of self-reported abdominal pain (RR 1.66, 95% CI 1.16 to 2.37, one trial, 1877 participants) and term prelabour rupture of membranes (PROM) (average RR 1.77, 95% CI 1.37 to 2.28, two trials, 2504 participants, I² = 0%); however, there was no corresponding increased risk for preterm PROM (average RR 1.27, 95% CI 0.93 to 1.75, five trials, 1999 participants, I² = 66%; low quality evidence). There were no clear differences between the vitamin E and placebo or control groups for any other maternal or infant outcomes. There were no clear differing patterns in subgroups of women based on the timing of commencement of supplementation or baseline risk of adverse pregnancy outcomes. The GRADE quality of the evidence was high for preterm birth, intrauterine growth restriction and placental abruption, moderate for stillbirth and clinical pre-eclampsia, and low for preterm PROM.

AUTHORS' CONCLUSIONS

The data do not support routine vitamin E supplementation in combination with other supplements for the prevention of stillbirth, neonatal death, preterm birth, pre-eclampsia, preterm or term PROM or poor fetal growth. Further research is required to elucidate the possible role of vitamin E in the prevention of placental abruption. There was no convincing evidence that vitamin E supplementation in combination with other supplements results in other important benefits or harms.

DNA damage and its cellular response in mother and fetus exposed to hyperglycemic environment

The increased production of reactive oxygen species (ROS) plays a key role in pathogenesis of diabetic complications. ROS are generated by exogenous and endogenous factors such as during hyperglycemia. When ROS production exceeds the detoxification and scavenging capacity of the cell, oxidative stress ensues. Oxidative stress induces DNA damage and when DNA damage exceeds the cellular capacity to repair it, the accumulation of errors can overwhelm the cell resulting in cell death or fixation of genome mutations that can be transmitted to future cell generations. These mutations can lead to and/or play a role in cancer development. This review aims at (i) understanding the types and consequences of DNA damage during hyperglycemic pregnancy; (ii) identifying the biological role of DNA repair during pregnancy, and (iii) proposing clinical interventions to maintain genome integrity. While hyperglycemia can damage the maternal genetic material, the impact of hyperglycemia on fetal cells is still unclear. DNA repair mechanisms may be important to prevent the deleterious effects of hyperglycemia both in mother and in fetus DNA and, as such, prevent the development of diseases in adulthood. Hence, in clinical practice, maternal glycemic control may represent an important point of intervention to prevent the deleterious effects of maternal hyperglycemia to DNA.

Antenatal interventions to reduce preterm birth: an overview of Cochrane Systematic Reviews

BACKGROUND

Several factors are associated with an increased risk of preterm birth (PTB); therefore, various interventions might have the potential to influence it. Due to the large number of interventions that address PTB, the objective of this overview is to summarise evidence from Cochrane reviews regarding the effects and safety of these different interventions.

METHODS

We conducted a systematic literature search in the Cochrane Database of Systematic Reviews. Included reviews should be based on randomised controlled trials comparing antenatal non-pharmacological and pharmacological interventions that directly or indirectly address PTB with placebo/no treatment or routine care in pregnant women at less than 37 completed weeks of gestation without signs of threatened preterm labour. We considered PTB at less than 37 completed weeks of gestation as the primary outcome.

RESULTS

We included 56 Cochrane systematic reviews. Three interventions increased PTB risk significantly. Twelve interventions led to a statistically significant lower incidence of PTBs. However, this reduction was mostly observed in defined at-risk subgroups of pregnant women. The remaining antenatal interventions failed to prove a significant effect on PTB < 37 weeks, but some of them at least showed a positive effect in secondary outcomes (e.g., reduction in early PTBs). As an unintended result of this review, we identified 28 additional Cochrane reviews which intended to report on PTB < 37 weeks, but were not able to find any RCTs reporting appropriate data.

CONCLUSIONS

The possible effects of a diverse range of interventions on PTB have been evaluated in Cochrane systematic reviews. Few interventions have been demonstrated to be effective and a small number have been found to be harmful. For around half of the interventions evaluated, the Cochrane review concluded that there was insufficient evidence to provide sound recommendations for clinical practice. No RCT evidence is available for a number of potentially relevant interventions.

Prenatal vitamin C deficiency results in differential levels of oxidative stress during late gestation in foetal guinea pig brains

Antioxidant defences are comparatively low during foetal development making the brain particularly susceptible to oxidative stress during antioxidant deficiencies. The brain is one of the organs containing the highest concentration of vitamin C (VitC) and VitC deficiency during foetal development may place the brain at risk of redox status imbalance. In the present study, we investigated the developmental pattern and effect of VitC deficiency on antioxidants, vitamin E and superoxide dismutase (SOD), assessed oxidative damage by measuring malondialdehyde (MDA), hydroxynonenal (HNE) and nitrotyrosine (NT) and analysed gene and protein expression of apoptosis marker caspase-3 in the guinea pig foetal brain at two gestational (GD) time points, GD 45/pre-term and GD 56/near term following either a VitC sufficient (CTRL) or deficient (DEF) maternal dietary regime. We show that except for SOD, antioxidants and oxidative damage markers are differentially expressed between the two GDs, with high VitC (p<0.0001), NT modified proteins (p<0.0001) and active caspase-3 levels (p<0.05) at pre-term and high vitamin E levels (p<0.0001), HNE (p<0.0001) and MDA (p<0.0001) at near term. VitC deficiency significantly increased SOD activity (p<0.0001) compared to CTRLs at both GDs indicating a compensatory response, however, low levels of VitC significantly elevated MDA levels (p<0.05) in DEF at near term. Our results show a differential regulation of the investigated markers during late gestation and suggest that immature brains are susceptible to oxidative stress due to prenatal vitC deficiency in spite of an induction of protective adaptation mechanisms.

Maternal dietary nutrient intake and risk of preterm delivery

OBJECTIVE

To examine maternal dietary intake and preterm delivery.

STUDY DESIGN

Data included 5738 deliveries from the National Birth Defects Prevention Study. Odds ratios (ORs) reflected risks of delivery at <32, 32-34, or 35-36 versus ≥ 37 weeks for maternal intake in the lowest or highest quartile of nutrient intake compared with the middle two.

RESULTS

Among deliveries < 32 weeks, many ORs were ≥ 1.5 or ≤ 0.7, but few confidence intervals excluded one. ORs were ≥ 1.5 for lowest quartiles of protein, thiamin, riboflavin, choline, vitamin A, α-carotene, β-carotene, vitamin E, iron, copper, and zinc and for highest quartiles of carbohydrate, glycemic index, and Mediterranean Diet Score. ORs were ≤ 0.7 for lowest quartiles of glycemic index and betaine and for highest quartiles of protein, alanine, methionine, vitamin B6, betaine, and calcium. Few ORs met these criteria for later preterm deliveries.

CONCLUSIONS

Results suggested an association of nutrient intake with earlier preterm deliveries.

Effect of Drakshavaleha in cyclophosphamide induced weight loss and reduction in crown-rump length in developing mice embryo

Being an anti-mitotic and apoptosis inducing agent, Cyclophosphamide (CP) causes stunting in size and loss of body weight of the pups on intra-peritoneal injection (10 mg/kg) to pregnant mice on day 11 of gestation. Loss of body weight due to CP administration could be minimized by feeding Drakshavaleha (16 g/kg) orally to pregnant mice from day "0" to day "18" of their gestation. Recovery observed in terms of body weight of the pups was statistically significant (P < 0.001) in Drakshavaleha treated pups. Drakshavaleha also recovered the crown-rump length of the pups occurred due to CP administration. Growth retardation with decreased fetal weight was observed in all CP treated pups when compared with the controls.

The fetal origins of the metabolic syndrome: can we intervene?

Epidemiological studies have suggested that metabolic programming begins during fetal life and adverse events in utero are a critical factor in the etiology of chronic diseases and overall health. While the underlying molecular mechanisms linking impaired fetal development to these adult diseases are being elucidated, little is known about how we can intervene early in life to diminish the incidence and severity of these long-term diseases. This paper highlights the latest clinical and pharmaceutical studies addressing how dietary intervention in fetal and neonatal life may be able to prevent aspects of the metabolic syndrome associated with IUGR pregnancies.

Association between intake of artificially sweetened and sugar-sweetened beverages and preterm delivery: a large prospective cohort study

BACKGROUND

Artificially sweetened (AS) and sugar-sweetened (SS) beverages are commonly consumed during pregnancy. A recent Danish study reported that the daily intake of an AS beverage was associated with an increased risk of preterm delivery.

OBJECTIVE

We examined the intake of AS and SS beverages in pregnant women to replicate the Danish study and observe whether AS intake is indeed associated with preterm delivery.

DESIGN

This was a prospective study of 60,761 pregnant women in the Norwegian Mother and Child Cohort Study. Intakes of carbonated and noncarbonated AS and SS beverages and use of artificial sweeteners in hot drinks were assessed by a self-reported food-frequency questionnaire in midpregnancy. Preterm delivery was the primary outcome, and data were obtained from the Norwegian Medical Birth Registry.

RESULTS

Intakes of both AS and SS beverages increased with increasing BMI and energy intake and were higher in women with less education, in daily smokers, and in single women. A high intake of AS beverages was associated with preterm delivery; the adjusted OR for those drinking >1 serving/d was 1.11 (95% CI: 1.00, 1.24). Drinking >1 serving of SS beverages per day was also associated with an increased risk of preterm delivery (adjusted OR: 1.25; 95% CI: 1.08, 1.45). The trend tests were positive for both beverage types.

CONCLUSION

This study suggests that a high intake of both AS and SS beverages is associated with an increased risk of preterm delivery.

Gaps in the evidence for prevention and treatment of maternal anaemia: a review of systematic reviews

BACKGROUND

Anaemia, in particular due to iron deficiency, is common in pregnancy with associated negative outcomes for mother and infant. However, there is evidence of significant variation in management. The objectives of this review of systematic reviews were to analyse and summarise the evidence base, identify gaps in the evidence and develop a research agenda for this important component of maternity care.

METHODS

Multiple databases were searched, including MEDLINE, EMBASE and The Cochrane Library. All systematic reviews relating to interventions to prevent and treat anaemia in the antenatal and postnatal period were eligible. Two reviewers independently assessed data inclusion, extraction and quality of methodology.

RESULTS

27 reviews were included, all reporting on the prevention and treatment of anaemia in the antenatal (n = 24) and postnatal periods (n = 3). Using AMSTAR as the assessment tool for methodological quality, only 12 of the 27 were rated as high quality reviews. The greatest number of reviews covered antenatal nutritional supplementation for the prevention of anaemia (n = 19). Iron supplementation was the most extensively researched, but with ongoing uncertainty about optimal dose and regimen. Few identified reviews addressed anaemia management post-partum or correlations between laboratory and clinical outcomes, and no reviews reported on clinical symptoms of anaemia.

CONCLUSIONS

The review highlights evidence gaps including the management of anaemia in the postnatal period, screening for anaemia, and optimal interventions for treatment. Research priorities include developing standardised approaches to reporting of laboratory outcomes, and information on clinical outcomes relevant to the experiences of pregnant women.

Antioxidants for preventing preeclampsia: a systematic review

OBJECTIVE

To investigate the efficacy of antioxidants for preventing preeclampsia and other maternal and fetal complications among pregnant women with low, moderate, or high risk of preeclampsia.

METHODS

We searched MEDLINE, Embase, CENTRAL, mRCT, and other databases, with no language or publication restrictions. Two independent reviewers selected randomized controlled trials that evaluated the use of antioxidants versus placebo and extracted the relevant data. Relative risks (RRs) and 95% confidence intervals (95% CIs) were calculated. The data were compiled through the random effects model.

MAIN RESULTS

Fifteen studies were included (21,012 women and 21,647 fetuses). No statistically significant difference was found between women who received antioxidant treatment and women who received placebo for preeclampsia (RR = 0.92; 95% CI: 0.82-1.04), severe preeclampsia (RR = 1.03; 95% CI: 0.87-1.22), preterm birth (RR = 1.03; 95% CI: 0.94-1.14), and small for gestational age <10th centile (RR = 0.92; 95% CI: 0.80-1.05). Side effects were numerically more frequent in the antioxidants group compared to placebo, but without significant statistical difference (RR = 1.24; 95% CI: 0.85-1.80).

CONCLUSIONS

The available evidence reviewed does not support the use of antioxidants during pregnancy for the prevention of preeclampsia and other outcomes.

Relationships among maternal nutrient intake and placental biomarkers during the 1st trimester in low-income women

PURPOSE

Pre-eclampsia is a multi-system disorder caused by inadequate placentation in early pregnancy; however, little is known about the influence of nutrient intake on placental development during the crucial 1st trimester. The objective of this study was to examine the relationships between nutrient intake and the raw values and ratios of angiogenic [placental growth factor (PlGF)] and antiangiogenic [soluble fms-like tyrosine kinase-1 (sFlt-1) and soluble endoglin (sEng)] placental biomarkers in the 1st trimester.

METHODS

A cross-sectional study of low-income, pregnant women (n = 118). Average nutrient intake was calculated from three 24-h dietary recalls. Biomarker values were adjusted for gestational age and nutrients were adjusted for energy.

RESULTS

The angiogenic to antiangiogenic ratio [PlGF/(sFlt-1 × sEng)] was positively related to intake of vitamin D (r = 0.24), vitamin B(2) (r = 0.25), B(12) (r = 0.20), dietary folate equivalents (r = 0.19), iron (r = 0.19), and zinc (r = 0.19) and negatively related to transfats (r = -0.24). Principal component analysis revealed that a vitamin/mineral factor [t (112) = 2.58, p = 0.011] and transfats factor [t (112) = -2.03, p = 0.045] were significant predictors of the PlGF/(sFlt-1 × sEng) ratio. The vitamin and mineral factor was a significant predictor of sFlt-1 [t (122) = 2.29, p = 0.024].

CONCLUSIONS

Expression of placental biomarkers in the early weeks of pregnancy may be influenced by intake of nutrients. Understanding the influence of maternal nutrient intake and placental development in the 1st trimester may provide the opportunity to avert the development or blunt the severity of preeclampsia.

Quantifying the fall in mortality associated with interventions related to hypertensive diseases of pregnancy

BACKGROUND

In this paper we review the evidence of the effect of health interventions on mortality reduction from hypertensive diseases in pregnancy (HDP). We chose HDP because they represent a major cause of death in low income countries and evidence of effect on maternal mortality from randomised studies is available for some interventions.

METHODS

We used four approaches to review the evidence of the effect of interventions to prevent or treat HDP on mortality reduction from HDP. We first reviewed the Cochrane Library to identify systematic reviews and individual trials of the efficacy of single interventions for the prevention or treatment of HDP. We then searched the literature for articles quantifying the impact of maternal health interventions on the reduction of maternal mortality at the population level and describe the approaches used by various authors for interventions related to HDP. Third, we examined levels of HDP-specific mortality over time or between regions in an attempt to quantify the actual or potential reduction in mortality from HDP in these regions or over time. Lastly, we compared case fatality rates in women with HDP-related severe acute maternal morbidity with those reported historically in high income countries before any effective treatment was available.

RESULTS

The Cochrane review identified 5 effective interventions: routine calcium supplementation in pregnancy, antiplatelet agents during pregnancy in women at risk of pre-eclampsia, Magnesium sulphate (MgS04) for the treatment of eclampsia, MgS04 for the treatment of pre-eclampsia, and hypertensive drugs for the treatment of mild to moderate hypertension in pregnancy.We found 10 studies quantifying the effect of maternal health interventions on reducing maternal mortality from HDP, but the heterogeneity in the methods make it difficult to draw uniform conclusions for effectiveness of interventions at various levels of the health system. Most authors include a health systems dimension aimed at separating interventions that can be delivered at the primary or health centre level from those that require hospital treatment, but definitions are rarely provided and there is no consistency in the types of interventions that are deemed effective at the various levels.The low levels of HDP related mortality in rural China and Sri Lanka suggest that reductions of 85% or more are within reach, provided that most women give birth with a health professional who can refer them to higher levels of care when necessary. Results from studies of severe acute maternal morbidity in Indonesia and Bolivia also suggest that mortality in women with severe pre-eclampsia or eclampsia in hospital can be reduced by more than 84%, even when the women arrive late.

CONCLUSIONS

The increasing emphasis on the rating of the quality of evidence has led to greater reliance on evidence from randomised controlled trials to estimate the effect of interventions. Yet evidence from randomised studies is often not available, the effects observed on morbidity may not translate in to mortality, and the distinction between efficacy and effectiveness may be difficult to make. We suggest that more use should be made of observational evidence, particularly since such data represent the actual effectiveness of packages of interventions in various settings.

Vitamins C and E for prevention of pre-eclampsia in women with type 1 diabetes (DAPIT): a randomised placebo-controlled trial

BACKGROUND

Results of several trials of antioxidant use during pregnancy have not shown a reduction in pre-eclampsia, but the effect in women with diabetes is unknown. We aimed to assess whether supplementation with vitamins C and E reduced incidence of pre-eclampsia in women with type 1 diabetes.

METHODS

We enrolled women from 25 UK antenatal metabolic clinics in a multicentre randomised placebo-controlled trial. Eligibility criteria were type 1 diabetes preceding pregnancy, presentation between 8 weeks' and 22 weeks' gestation, singleton pregnancy, and age 16 years or older. Women were randomly allocated in a 1:1 ratio to receive 1000 mg vitamin C and 400 IU vitamin E (alpha-tocopherol) or matched placebo daily until delivery. The randomisation sequence was stratified by centre with balanced blocks of eight patients. All trial personnel and participants were masked to treatment allocation. The primary endpoint was pre-eclampsia, which we defined as gestational hypertension with proteinuria. Analysis was by modified intention to treat. This study is registered, ISRCTN27214045.

FINDINGS

Between April, 2003, and June, 2008, 762 women were randomly allocated to treatment groups (379 vitamin supplementation, 383 placebo). The primary endpoint was assessed for 375 women allocated to receive vitamins, and 374 allocated to placebo. Rates of pre-eclampsia did not differ between vitamin (15%, n=57) and placebo (19%, 70) groups (risk ratio 0.81, 95% CI 0.59-1.12). No adverse maternal or neonatal outcomes were reported.

INTERPRETATION

Supplementation with vitamins C and E did not reduce risk of pre-eclampsia in women with type 1 diabetes. However, the possibility that vitamin supplementation might be beneficial in women with a low antioxidant status at baseline needs further testing.

FUNDING

The Wellcome Trust.

The impact of vitamin C supplementation in pregnancy and in vitro upon fetal membrane strength and remodeling

Generation of reactive oxygen species (ROS) has been suggested as a mechanism of fetal membrane (FM) weakening leading to rupture, particularly with preterm premature rupture of the fetal membranes (PROM). In vitro, FM incubation with tumor necrosis factor (TNF) mimics physiological FM weakening, concomitant with generation of ROS and collagen remodeling. Proinflammatory cytokines are also postulated to have a role in the development of the FM physiological weak zone where rupture normally initiates in-term gestations. We hypothesized that antioxidant treatment may block ROS development and resultant FM weakening. Two studies examining antioxidant effects upon FM strength were conducted, one in vivo and the other in vitro. Fetal membrane of patients enrolled in a multicenter placebo-controlled trial to determine the effect of vitamin C (1 g/day) and vitamin E (400 IU/day) upon complications of pre-eclampsia were examined for FM biomechanical properties and biochemical remodeling at birth. Separately, biomechanics and biochemical markers of remodeling were determined in FM fragments incubated with TNF with or without vitamin C preincubation. Supplemental dietary vitamin C in combination with vitamin E did not modify rupture strength, work to rupture, or matrix metalloproteinase-9 (MMP9; protein or activity) either within or outside the term FM physiological weak zone. In vitro, TNF decreased FM rupture strength by 50% while increasing MMP9 protein. Vitamin C did not inhibit these TNF-induced effects. Vitamin C alone had a weakening effect on FM in vitro. We speculate that vitamin C supplementation during pregnancy will not be useful in the prevention of preterm PROM.

Low ascorbic acid and increased oxidative stress in gulo(-/-) mice during development

Vitamin C (ascorbic acid, AA) depletion during prenatal and postnatal development can lead to oxidative stress in the developing brain and other organs. Such damage may lead to irreversible effects on later brain function. We studied the relationship between AA deficiency and oxidative stress during development in gulonolactone oxidase (gulo) knockout mice that are unable to synthesize their own ascorbic acid. Heterozygous gulo(+/-) mice can synthesize AA and typically have similar tissue levels to wild-type mice. Gulo(+/-) dams were mated with gulo(+/-) males to provide offspring of each possible genotype. Overall, embryonic day 20 (E20) and postnatal day 1 (P1) pups were protected against oxidative stress by sufficient AA transfer during pregnancy. On postnatal day 10 (P10) AA levels were dramatically lower in liver and cerebellum in gulo(-/-) mice and malondialdehyde (MDA) levels were significantly increased. In postnatal day 18 pups (P18) AA levels decreased further in gulo(-/-) mice and oxidative stress was observed in the accompanying elevations in MDA in liver, and F(2)-isoprostanes in cortex. Further, total glutathione levels were higher in gulo(-/-) mice in cortex, cerebellum and liver, indicating that a compensatory antioxidant system was activated. These data show a direct relationship between AA level and oxidative stress in the gulo(-/-) mice. They reinforce the critical role of ascorbic acid in preventing oxidative stress in the developing brain in animals that, like humans, cannot synthesize their own AA.

Evidence for perinatal and child health care guidelines in crisis settings: can Cochrane help?

BACKGROUND

It is important that healthcare provided in crisis settings is based on the best available research evidence. We reviewed guidelines for child and perinatal health care in crisis situations to determine whether they were based on research evidence, whether Cochrane systematic reviews were available in the clinical areas addressed by these guidelines and whether summaries of these reviews were provided in Evidence Aid.

METHODS

Broad internet searches were undertaken to identify relevant guidelines. Guidelines were appraised using AGREE and the clinical areas that were relevant to perinatal or child health were extracted. We searched The Cochrane Database of Systematic Reviews to identify potentially relevant reviews. For each review we determined how many trials were included, and how many were conducted in resource-limited settings.

RESULTS

Six guidelines met selection criteria. None of the included guidelines were clearly based on research evidence. 198 Cochrane reviews were potentially relevant to the guidelines. These reviews predominantly addressed nutrient supplementation, breastfeeding, malaria, maternal hypertension, premature labour and prevention of HIV transmission. Most reviews included studies from developing settings. However for large portions of the guidelines, particularly health services delivery, there were no relevant reviews. Only 18 (9.1%) reviews have summaries in Evidence Aid.

CONCLUSIONS

We did not identify any evidence-based guidelines for perinatal and child health care in disaster settings. We found many Cochrane reviews that could contribute to the evidence-base supporting future guidelines. However there are important issues to be addressed in terms of the relevance of the available reviews and increasing the number of reviews addressing health care delivery.

Reducing stillbirths: prevention and management of medical disorders and infections during pregnancy

BACKGROUND

An estimated two-thirds of the world's 3.2 million stillbirths occur antenatally, prior to labour, and are often overlooked in policy and programs. Poorly recognised, untreated or inadequately treated maternal infections such as syphilis and malaria, and maternal conditions including hypertensive disorders, are known risk factors for stillbirth.

METHODS

We undertook a systematic review of the evidence for 16 antenatal interventions with the potential to prevent stillbirths. We searched a range of sources including PubMed and the Cochrane Library. For interventions with prior Cochrane reviews, we conducted additional meta-analyses including eligible newer randomised controlled trials following the Cochrane protocol. We focused on interventions deliverable at the community level in low-/middle-income countries, where the burden of stillbirths is greatest.

RESULTS

Few of the studies we included reported stillbirth as an outcome; most that did were underpowered to assess this outcome. While Cochrane reviews or meta-analyses were available for many interventions, few focused on stillbirth or perinatal mortality as outcomes, and evidence was frequently conflicting. Several interventions showed clear evidence of impact on stillbirths, including heparin therapy for certain maternal indications; syphilis screening and treatment; and insecticide-treated bed nets for prevention of malaria. Other interventions, such as management of obstetric intrahepatic cholestasis, maternal anti-helminthic treatment, and intermittent preventive treatment of malaria, showed promising impact on stillbirth rates but require confirmatory studies. Several interventions reduced known risk factors for stillbirth (e.g., anti-hypertensive drugs for chronic hypertension), yet failed to show statistically significant impact on stillbirth or perinatal mortality rates. Periodontal disease emerged as a clear risk factor for stillbirth but no interventions have reduced stillbirth rates.

CONCLUSION

Evidence for some newly recognised risk factors for stillbirth, including periodontal disease, suggests the need for large, appropriately designed randomised trials to test whether intervention can minimise these risks and prevent stillbirths. Existing evidence strongly supports infection control measures, including syphilis screening and treatment and malaria prophylaxis in endemic areas, for preventing antepartum stillbirths. These interventions should be incorporated into antenatal care programs based on attributable risks and burden of disease.

Stillbirth in developing countries: a review of causes, risk factors and prevention strategies

OBJECTIVE

To understand the rates, causes and risk factors for stillbirth in developing countries as well as the strategies that have been evaluated to reduce stillbirth.

METHODS

We searched the English literature for 2003-2008 for all articles related to stillbirth and perinatal mortality in developing countries and reviewed all related publications.

RESULTS

Despite the large number of stillbirths worldwide, the topic of stillbirths in developing countries has received very little research, programmatic or policy attention. In many developing countries, almost half of the deliveries occur at home, and under-reporting of stillbirths is a significant problem. Reliable data about rates and causes are unavailable in many areas of the world. Nevertheless, of the estimated 3.2 million stillbirths that occur yearly world-wide, the vast majority occur in developing countries. Rates in many developing countries are 10-fold greater or more than in developed countries. There is not a standard international classification system that defines cause of death, nor is there agreement about the lower limits of birthweight or gestational age that define stillbirth, making comparisons of causes of stillbirth or rates over time or between sites problematic. From available data, prolonged and obstructed labour, pre-eclampsia and various infections, all without adequate treatment, appear to account for the majority of stillbirths in developing countries. Identification and treatment of maternal syphilis has been effective in reducing stillbirth risk, as has improvements in access to emergency obstetrical services and particularly caesarean section.

CONCLUSIONS

Further research is needed to understand the causes and the best preventive strategies for stillbirth specific to geographic areas. However, based on current data, better access to appropriate obstetric care, particularly during labour and delivery and better screening and treatment of syphilis should reduce developing country stillbirth rates dramatically.

Alpha-lipoic acid inhibits tumor necrosis factor-induced remodeling and weakening of human fetal membranes

Untimely rupture of the fetal membranes (FMs) is a major precipitant of preterm birth. Although the mechanism of FM weakening leading to rupture is not completely understood, proinflammatory cytokines, including tumor necrosis factor (TNF) and interleukin 1 beta (IL1B), have been shown to weaken FMs concomitant with the induction of reactive oxygen species, collagen remodeling, and prostaglandin release. We hypothesized that alpha-lipoic acid, a dietary antioxidant, may block the effect of inflammatory mediators and thereby inhibit FM weakening. Full-thickness FM fragments were incubated with control media or TNF, with or without alpha-lipoic acid pretreatment. Fetal membrane rupture strength and the release of matrix metalloproteinase 9 (MMP9) and prostaglandin E(2) (PGE(2)) from the full-thickness FM fragments were determined. The two constituent cell populations in amnion, the mechanically strongest FM component, were similarly examined. Amnion epithelial and mesenchymal cells were treated with TNF or IL1B, with or without alpha-lipoic acid pretreatment. MMP9 and PGE(2) were analyzed by ELISA, Western blot, and zymography. TNF decreased FM rupture strength 50% while increasing MMP9 and PGE(2) release. Lipoic acid inhibited these TNF-induced effects. Lipoic acid pretreatment also inhibited TNF- and IL1B-induced increases in MMP9 protein activity and release in amnion epithelial cells, as well as PGE(2) increases in both amnion epithelial and mesenchymal cells. In summary, lipoic acid pretreatment inhibited TNF-induced weakening of FM and cytokine-induced MMP9 and PGE(2) in both intact FM and amnion cells. We speculate that dietary supplementation with alpha-lipoic acid might prove clinically useful in prevention of preterm premature rupture of fetal membranes.