Magnesium and other nutrient deficiencies as possible causes of hypertension and low birthweight

Cardiometabolic Risk Factors Associated with Magnesium and Vitamin D Nutrients during Pregnancy-A Narrative Review

This narrative review comprehensively explores the cardiometabolic implications of two vital nutrients, magnesium and vitamin D, during gestation. Magnesium, a key regulator of vascular tone, glucose metabolism, and insulin sensitivity, plays a crucial role in mitigating gestational hypertension and diabetes, a point this review underscores. Conversely, vitamin D, critical for immune response and calcium level maintenance, is linked to gestational diabetes and hypertensive disorders of pregnancy. The authors aim to enhance comprehension of the complex interaction between these nutrients and cardiometabolic function in pregnancy, knowledge that is pivotal for optimizing maternal-fetal outcomes. The mother's health during pregnancy significantly influences the long-term development of the fetus. Recognizing the impact of these nutrient deficiencies on the physiology of cardiometabolic cycles underscores the importance of adequate nutritional support during pregnancy. It also emphasizes the pressing need for future research and targeted interventions to alleviate the burden of pregnancy complications, highlighting the crucial role of healthcare professionals, researchers, and policy makers in obstetrics and gynecology in this endeavor.

Exploring the Spectrum of Electrolyte Imbalances in Preeclampsia: Mechanisms, Implications, and Clinical Insights

Preeclampsia, a complex and perplexing disorder unique to pregnancy, is widely recognized as primarily originating from placental dysfunction and can only be resolved by the delivery of the fetus in severe cases. Preeclampsia is a prevalent medical issue during pregnancy and is associated with elevated rates of maternal and infant mortality and morbidity. The exact cause of preeclampsia remains uncertain, although multiple factors have been implicated in its development based on current knowledge. Preeclampsia is characterized by maternal endothelial dysfunction due to the presence of fetal-derived circulatory substances from the placenta. The condition is associated with various risk factors, including maternal comorbidities such as chronic renal disease, hypertension (HTN), and obesity. Additionally, a family history of preeclampsia, nulliparity, multiple gestations, previous instances of preeclampsia, or intrauterine fetal growth restriction (IUGR) are considered risk factors. Electrolytes, including sodium, potassium, and chloride, play a critical role in the function of vascular smooth muscles and may potentially contribute to the pathophysiology of hypertension. In this review, we have summarized the literature on electrolytes in preeclampsia by conducting an extensive systematic search of databases such as PubMed, Excerpta Medica database (EMBASE), and Medical Literature Analysis and Retrieval System Online (MEDLINE).

Maternal antioxidant micronutrient deficiencies among pre-eclamptic women in Enugu, Nigeria: a cross-sectional analytical study

OBJECTIVES

To determine the prevalence of antioxidant micronutrient deficiencies in pregnant women with pre-eclampsia and healthy pregnant women, and to assess the relationships between trace element deficiency in pregnancy and the severity of pre-eclampsia in Enugu, Nigeria.

METHODS

We performed a secondary analysis of a cross-sectional analytical study of serum concentrations of copper, selenium, zinc, magnesium, and manganese in 81 pregnant women with pre-eclampsia and healthy pregnant women (controls) who were matched for age, gestational age, body mass index, and parity. This study was performed at the University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu. Participants' sera were analyzed with an atomic absorption spectrophotometer.

RESULTS

Trace element deficiencies were common and similar between women with pre-eclampsia and controls. However, women with pre-eclampsia were more likely to be deficient in manganese than controls (odds ratio = 2.28, 95% confidence interval: 1.90-2.75). Among the micronutrients studied, only manganese concentrations were significantly lower in women without severe symptoms of pre-eclampsia than in those with severe symptoms of pre-eclampsia.

CONCLUSIONS

Micronutrient deficiency is common in pregnant women with pre-eclampsia and in healthy pregnant women in Enugu, Nigeria. Only manganese deficiency is higher in women with pre-eclampsia than in healthy pregnant women.

Effect of L-Arginine supplementation in pregnant women with chronic hypertension and previous placenta vascular disorders receiving Aspirin prophylaxis: a randomized control trial

BACKGROUND

The aim of the study is to evaluate the effects of supplementation with Arginine (L-Arg) 3g, (together with Magnesium (Mg) 350 mg and Salicilate (Sal) 100 mg) on maternal blood pressure (BP), uterine artery doppler PI and neonatal outcomes in women with high-risk pregnancy for chronic hypertension (CH) and other previous placenta vascular disorders (PVD) already treated with low dose of aspirin (LDA), as recommended by guidelines.

METHODS

We enrolled women affected by CH and other previous PVD referred to the High-Risk Clinic of the Mother-Infant Department of the University of Modena and Reggio Emilia from September 2017 to June 2019. The study design was a controlled, randomized trial of oral supplementation of L-Arg 3g (together with Mg 350 mg and Sal extract 100 mg) + LDA 100 mg/die versus only LDA 100 mg/die. Inclusion criteria were: singleton pregnancy; diagnosis of chronic hypertension, previous preeclampsia < 34 weeks, previous intrauterine growth restriction (IUGR) < 10° centile or previous stillbirth (SB) related to placenta vascular disorders; gestational age < 14 weeks. Each woman was enrolled between 12-14 weeks gestation and underwent 24-h ambulatory BP monitoring with an automatic device (SpaceLab 92710, Critikon, WA), repeated at 18-20th and 24-26th weeks. Moreover Uterine artery Doppler ultrasound evaluation including PI were performed at 18-20 weeks gestation and repeated at 24-26th weeks. Pregnancy outcomes data were collected in a password protected database.

RESULTS

Seventy-nine women agreed to participate in the study. No significant differences between the demographic characteristics in the two groups at enrollment (Group LDA + L-Arg: 30 patients versus Group LDA: 49 patient) were found. In the LDA-L-Arg group there isn't the significant increase in both systolic (127.22 ± 12.02 and 132.75 ± 7.51 mmHg, p=0.002) and diastolic (75.85 ± 8.53 and 83.63 ± 6.05 mmHg, p=0.0000) BP values at 24-26 weeks reveled in the LDA group. The value of the Uterine Artery Doppler median PI > 95° centile at 24-26 weeks show a significant reduction in the LDA+L-Arg group respect the LDA group (7 women, 23.3% vs 21 women, 42.9%; p=0.04). A significantly lower percentage of women received new antihypertensive drugs in the LDA+ L-Arg group than the LDA group (6.7% vs 24.5%) (p= 0.02). There was neither statistically significant difference in perinatal outcomes between 2 groups, except for trend of significance.

CONCLUSIONS

Although we found only trends of improvements of perinatal outcomes in LDA+LArg group, considering the promising results on BP values, uterine artery PI and the low need to start a new antihypertensive treatment, thus the resulting impact in reducing pregnancy medicalization, number of maternal-fetal well-being monitoring visits and the need of induction of labour, we believe that further studies should be performed to enlarge our observation and clarify the role of L-Arg 3g supplementation as a protective integration in high-risk pregnancies already in prophylaxis with LDA.

Magnesium supplementation and preeclampsia in low-income pregnant women - a randomized double-blind clinical trial

BACKGROUND

Preeclampsia is the major cause of maternal morbidity and mortality in developing countries. Magnesium sulfate is considered first-line therapy against eclampsia and magnesium deficiency in pregnancy has been associated with unfavourable perinatal outcomes. However there are doubts if magnesium supplementation during pregnancy can previne preeclampsia especially in population with high nutritional risk. This trial aims to verify the effect of oral magnesium supplmentation on preeclampsia incidence in low income pregnant women.

METHODS

This randomized, double-blind, placebo-controlled trial investigated the effect of oral magnesium citrate supplementation for preeclampsia in low-income Brazilian pregnant women, i.e. annual per capita income of US$ 1025 or less. Participants were admitted to the study with gestational age between 12 and 20 weeks. Magnesium serum level was measured pre-randomization and participants with hypermagnesemia were excluded. After randomizationg participants received magnesium citrate capsule (300 mg magnesium citrate) or a daily placebo capsule, until delivery. Intent-to-treat analysis was performed.

RESULTS

A total of 416 pregnant women were screened and 318 enrolled according to the inclusion criteria; 159 for each arm. Twenty-eight pregnant women were lost to follow-up. 55/290 (18.9%) of pregnant women developed preeclampsia; 26/143 (18.1%) in magnesium group and 29/147 (19.7%) in the control group; OR 0.90 (CI 95% 0.48-1.69), p = 0.747. No cases of eclampsia were registered.

CONCLUSION

Oral magnesium supplementation did not reduce preeclampsia incidence in low-income and low-risk pregnant women.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov (Identifier NCT02032186), December 19, 2013.

Preterm Birth: A Narrative Review of the Current Evidence on Nutritional and Bioactive Solutions for Risk Reduction

Preterm birth (PTB) (<37 weeks of gestation) is the leading cause of newborn death and a risk factor for short and long-term adverse health outcomes. Most cases are of unknown cause. Although the mechanisms triggering PTB remain unclear, an inappropriate increase in net inflammatory load seems to be key. To date, interventions that reduce the risk of PTB are effective only in specific groups of women, probably due to the heterogeneity of its etiopathogenesis. Use of progesterone is the most effective, but only in singleton pregnancies with history of PTB. Thus, primary prevention is greatly needed and nutritional and bioactive solutions are a promising alternative. Among these, docosahexaenoic acid (DHA) is the most promising to reduce the risk for early PTB. Other potential nutrient interventions include the administration of zinc (possibly limited to populations with low nutritional status or poor zinc status) and vitamin D; additional preliminary evidence exists for vitamin A, calcium, iron, folic acid, combined iron-folate, magnesium, multiple micronutrients, and probiotics. Considering the public health relevance of PTB, promising interventions should be studied in large and well-designed clinical trials. The objective of this review is to describe, summarize, and discuss the existing evidence on nutritional and bioactive solutions for reducing the risk of PTB.

Change of the levels of trace elements and heavy metals in threatened abortion

BACKROUND

This study aimed to investigate the impact of changes in the serum levels of trace elements and heavy metals in threatened abortion, which is a common complication in early pregnancy. Earlier studies have shown that changes in the serum levels of some trace elements and increased serum concentrations of heavy metals are associated with spontaneous abortion; however, this relationship has not been fully clarified.

METHODS

The patient group consisted of 45 pregnant women diagnosed with threatened abortion. There were 40 healthy nonpregnant women in the control group. Blood samples were obtained from the patients and the healthy controls, and the concentrations of serum trace elements and heavy metals were measured using atomic absorption spectrophotometry.

RESULTS

Statistically significant decreases were found in the serum zinc (Zn), iron (Fe), magnesium (Mg) and manganese (Mn) levels, and significant increases were found in the serum copper (Cu), cadmium (Cd) and lead (Pb) levels in cases of threatened abortion in comparison to the controls (p < 0.001). However, there was no difference between the groups in terms of the serum cobalt (Co) levels (p > 0.001).

CONCLUSION

Changes in the balance of some essential trace elements (especially decreases in Fe and Zn) and elevated concentrations of some toxic heavy metals in the blood may be important diagnostic and prognostic parameters for threatened abortion.

Effect of Magnesium Supplement on Pregnancy Outcomes: A Randomized Control Trial

BACKGROUND

Magnesium (Mg) is an essential mineral required to regulate body temperature, nucleic acid, and protein synthesis with an important role in maintaining nerve and muscle cell electrical potentials. It may reduce fetal growth restriction and preeclampsia as well as increase birth weight. This study aimed to assess the effects of consuming Mg supplementation during pregnancy on pregnancy outcomes.

MATERIALS AND METHODS

This is a randomized controlled trial with three sixty populated groups of pregnant women. Participants were randomized to treatment or control groups through random table numbers. Participants with Mg serum levels more than 1.9 mg/dl considered as control group A randomly. They just received one multimineral tablet once a day until the end of pregnancy participants with hypomagnesemia consider as Group B and C. Participants in Group B received one multimineral tablet daily until the end of pregnancy. Participants in Group C received 200 mg effervescent Mg tablet from Vitafit Company once daily for 1 month, and also they consumed one multimineral tablet from Alhavi Company, which contains 100 mg Mg, once a day until the end of pregnancy. Intrauterine growth retardation, preterm labor, maternal body mass index, neonatal weight, pregnancy-induced hypertension, preeclampsia, gestational diabetes mellitus, cramps of the leg Apgar score were compared between three groups.

RESULTS

In all pregnancy outcomes, Group C that received effervescent Mg tablet plus multimineral showed a better result than other groups, and frequency of complications of pregnancy was fewer than the other two groups and showed a significant difference.

CONCLUSION

Mg supplement during pregnancy likely decrease probability occurrence of many complications of pregnancy.

The BRAzil MAGnesium (BRAMAG) trial: a randomized clinical trial of oral magnesium supplementation in pregnancy for the prevention of preterm birth and perinatal and maternal morbidity

BACKGROUND

Preterm birth is the leading cause of infant mortality globally, including Brazil. We will evaluate whether oral magnesium citrate reduces the risk of placental dysfunction and its negative consequences for both the fetus and mother, which, in turn, should reduce the need for indicated preterm delivery.

METHODS/DESIGN

We will complete a multicenter, randomized double-blind clinical trial comparing oral magnesium citrate 150 mg twice daily (n = 2000 women) to matched placebo (n = 1000 women), starting at 121/7 to 206/7 weeks gestation and continued until delivery. We will include women at higher risk for placental dysfunction, based on clinical factors from a prior pregnancy (e.g., prior preterm delivery, stillbirth or preeclampsia) or the current pregnancy (e.g., chronic hypertension, pre-pregnancy diabetes mellitus, maternal age > 35 years or pre-pregnancy maternal body mass index > 30 kg/m2). The primary perinatal outcome is a composite of preterm birth < 37 weeks gestation, stillbirth > 20 weeks gestation, neonatal death < 28 days, or SGA birthweight < 3rd percentile. The primary composite maternal outcome is preeclampsia arising < 37 weeks gestation, severe non-proteinuric hypertension arising < 37 weeks gestation, placental abruption, maternal stroke during pregnancy or ≤ 7 days after delivery, or maternal death during pregnancy or ≤ 7 days after delivery.

DISCUSSION

The results of this randomized clinical trial may be especially relevant in low and middle income countries that have high rates of prematurity and limited resources for acute newborn and maternal care.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier NCT02032186, registered December 19, 2013.

The role of calcium, magnesium, and zinc in pre-eclampsia

Pre-eclampsia is the most common medical complication of pregnancy associated with increased maternal and infant mortality and morbidity. Its exact etiology is not known, although several evidences indicate that various elements might play an important role in pre-eclampsia. This study was carried out to analyze and to compare the concentration of calcium, magnesium, and zinc in the serum of women with pre-eclampsia and in normal pregnant women. Fifty clinically diagnosed patients with pre-eclampsia (25 with mild and 25 with severe pre-eclampsia) and 50 normal pregnant controls were enrolled in this study. The serum calcium, magnesium, and zinc levels were estimated with an atomic absorption spectrophotometer. The mean serum levels of calcium, magnesium, and zinc in normal pregnant group were 2.45 +/- 0.18 mmol/L, 0.79 +/- 0.13 mmol/L, and 15.64 +/- 2.4 micromol/L, respectively, while in mild pre-eclamptic group, these were 2.12 +/- 0.15 mmol/L, 0.67 +/- 0.14 mmol/L, and 12.72 +/- 1.7 micromol/L, respectively. Serum levels in severe pre-eclamptic group were 1.94 +/- 0.09 mmol/L, 0.62 +/- 0.11 mmol/L, and 12.04 +/- 1.4 micromol/L, respectively. These results indicate that reduction in serum levels of calcium, magnesium, and zinc during pregnancy might be possible contributors in etiology of pre-eclampsia, and supplementation of these elements to diet may be of value to prevent pre-eclampsia.

Identification of the Alzheimer's disease amyloid precursor protein (APP) and its homologue APLP2 as essential modulators of glucose and insulin homeostasis and growth

The amyloid precursor protein (APP), the source of the neurotoxic amyloid beta (A beta) peptide involved in Alzheimer's disease (AD), belongs to a conserved family of related proteins. In mammals, the APP family contains amyloid precursor-like protein 1 (APLP1) and amyloid precursor-like protein 2 (APLP2). Whilst a number of activities have been attributed to the APP family, an overall function has not been definitively established. While ablating either the APP or APLP2 gene in mice produces minimal phenotypic change, the combined knockout of these genes in mice causes postnatal mortality. Postnatal survival therefore requires a shared but unknown function of APP and APLP2. To investigate the biochemical basis for the postnatal lethality, plasma was analysed from double knockout mice (APP-/- APLP2-/-) 2 days before birth, at gestational day E17, and from mice at 12-16 h after birth. The postnatal double knockouts had 66% lower plasma glucose levels than their wild-type controls and 50% lower than their single knockout counterparts. Interestingly, the postnatal double knockouts displayed hyperinsulinaemia, as shown by inappropriate plasma insulin levels, given their degree of hypoglycaemia. The single knockout mice also showed hyperinsulinaemia and had 31% lower plasma glucose than the wild-types. While the double knockouts did not survive more than 24 h after birth, the single knockouts reached adulthood and their hypoglycaemia continued. Therefore, APP and APLP2 expression modulates plasma insulin and glucose concentrations. Plasma calcium, magnesium and phosphate were also significantly reduced in the double knockouts compared to the wild-types, and they showed distinctive growth restriction, suggesting the involvement of a metabolic impairment. These results link the expression of the APP and APLP2 genes with glucose homeostasis and growth and therefore identify a novel function for the APP family.

Long-term effect of a plant-based diet on magnesium status during pregnancy

OBJECTIVE

To compare dietary magnesium intake and magnesium concentrations in serum, red blood cells (RBC) and urine during pregnancy of women habitually following a long-term plant-based diet and of women following an average Western (control) diet.

DESIGN

Prospective study during pregnancy.

SETTING

Giessen, Germany.

SUBJECTS

Healthy pregnant women (n=108) in their 9-12th, 20-22nd and 36-38th gestational week habitually following a plant-based diet for more than 3 y or an average Western diet. The vegetarians were subdivided into ovo-lacto vegetarians (n=27) and low-meat eaters (n=43).

RESULTS

Significant higher dietary magnesium intakes were observed in pregnant women consuming a plant-based diet (508+/-14 mg/day for ovo-lacto vegetarians, P<0.001 and 504+/-11 mg/day for low-meat eaters, P<0.001) than in pregnant women consuming a control diet (412+/-9 mg/day). Serum magnesium concentrations were similar in all diet groups whereas RBC magnesium was slightly higher in low-meat eaters than in controls (P=0.058). Urinary magnesium excretion was higher in ovo-lacto vegetarians (P=0.023), followed by low-meat eaters (P=0.017) when compared to the control group. During the third trimester of pregnancy, the frequency and the occurrence of calf cramps was lower in the plant-based diet group than in the control group (P=0.004 and 0.008).

CONCLUSIONS

Owing to a higher dietary magnesium intake confirmed by higher urinary magnesium excretion, habitual plant-based diets result in a slightly improved magnesium status during pregnancy and reduce the frequency of calf cramps during the third trimester of pregnancy compared to an average Western diet. Therefore, plant-based diets during pregnancy can be recommended with regard to magnesium supply.

Prevalence of multiple micronutrient deficiencies amongst pregnant women in a rural area of Haryana

Deficiencies of micronutrients (zinc, iron, folic acid and iodine) during pregnancy are known causes of Low Birth Weight (LBW). Studies have documented status of one or two micronutrients amongst pregnant women (PW). However, no attempt has been made to concurrently assess the prevalence of multiple micronutrient deficiencies and the factors associated with them amongst PW.

OBJECTIVE

The present study was undertaken to assess the prevalence of multiple micronutrient deficiencies amongst PW in a rural area.

METHODS

A community based cross sectional survey was conducted in six villages of a rural area of district Faridabad in Haryana state, India during November 2000 and October 2001. All PW aged 18 years or more, with pregnancy duration of more than 28 weeks were enrolled. Data were collected on socio-economic status and other demographic parameters. Serum zinc, copper and magnesium levels were estimated by utilizing the Atomic absorption spectrophotometry (AAS); serum ferritin and folate was estimated by Enzyme Linked Immuno Sorbent Assay (ELISA) method and the Radio-Immuno Assay (RIA) method, respectively and serum thyroid stimulating hormone (TSH) level was estimated by the Abbot AxSYM System. Serum zinc, copper, magnesium, ferritin, and folate levels less than 70.0 microg/dl, 80.0 microg/dl, 1.80 mg/dl, 15 ng/ml, and 3 ng/ml, respectively were considered as indicative of deficiency for respective micronutrients. The TSH levels of 4.670 and more indicated iodine deficiency status. Dietary intake of micronutrients was assessed utilizing 1-day 24-hour dietary recall methodology. Food consumption pattern was assessed utilizing the food frequency questionnaire methodology.

RESULTS

Nearly 73.5, 2.7, 43.6, 73.4, 26.3, and 6.4 percent PW were deficient in zinc, copper, magnesium, iron, folic acid and iodine, respectively. The highest concurrent prevalence of two, three, four and five micronutrient deficiency was of zinc and iron (54.9%); zinc, magnesium and iron (25.6%); zinc, magnesium, iron and folic acid (9.3%) and zinc, magnesium, iron, folic acid and iodine (0.8%), respectively. No pregnant woman was found to have concomitant deficiencies of all the six micronutrients. Dietary intake data revealed an inadequate nutrient intake. Over 19% PW were consuming less than 50% of the recommended calories. Similarly, 99, 86.2, 75.4, 23.6, 3.9 percent of the PW were consuming less than 50% of the recommended folic acid, zinc, iron, copper, and magnesium. The consumption of food groups rich in micronutrients (pulses, vegetables, fruits, nuts and oil seeds, animal foods) was infrequent. Univariate and Multivariate logistic regression analysis revealed that low dietary intake of nutrients, low frequency of consumption of food groups rich in micronutrients and increased reproductive cycles with short interpregnancy intervals were important factors leading to micronutrient deficiencies.

CONCLUSION

There was a high prevalence of micronutrient deficiencies amongst the PW of the area, possibly due to the poor dietary intake of food and low frequency of consumption of food groups rich in micronutrients. The concurrent prevalence of two, three, four and five micronutrient deficiencies were common.

Serum magnesium level among pregnant women in a rural community of Haryana State, India

OBJECTIVE

Assessment of serum magnesium levels among pregnant women in a rural community.

DESIGN

A community-based cross-sectional study.

SETTING

Investigation was conducted in six villages of a rural block of District Faridabad, Haryana State, India.

SUBJECTS

In total, 283 pregnant women with pregnancy duration of 28 weeks and more were enrolled for the detailed study. Blood from the antecubital vein was drawn and serum magnesium levels were estimated by the atomic absorption spectrophotometric method.

RESULTS

In all, 44% of the pregnant women had serum levels less than the normal level (1.80 mg/dl). There was a significant decrease (P=0.01) in serum magnesium levels with the increase in parity.

CONCLUSION

A high prevalence of magnesium deficiency was found among the pregnant women.

Interrelationship of magnesium and estrogen in cardiovascular and bone disorders, eclampsia, migraine and premenstrual syndrome

The anticonvulsive and antihypertensive values of magnesium (Mg) in eclampsia, and its antiarrhythmic applications in a variety of cardiac diseases, have caused Mg to be considered only for parenteral administration by many physicians. In contrast, nutritionists have long recognized Mg as an essential nutrient, because severe deficiencies elicit neuromuscular manifestations similar to those justifying its use in eclampsia. More recently, this element has been used to favorably influence latent tetany with and without thrombotic complications, to delay preterm birth, to influence premenstrual syndrome, and to ameliorate migraine headaches. Most of these disorders exclusively or largely afflict women. The lesions of arteries and heart caused by experimental Mg deficiency have been well documented and may contribute to human cardiovascular disease. Estrogen's enhancement of Mg utilization and uptake by soft tissues and bone may explain resistance of young women to heart disease and osteoporosis, as well as increased prevalence of these diseases when estrogen secretion ceases. However, estrogen-induced shifts of Mg can be deleterious when estrogen levels are high and Mg intake is suboptimal. The resultant lowering of blood Mg can increase the Ca/Mg ratio, thus favoring coagulation. With Ca supplementation in the face of commonly low Mg intake, risk of thrombosis increases.

Magnesium intake and status and pregnancy outcome in a Danish population

OBJECTIVE

To investigate the relation between pregnancy outcome and magnesium intake and status.

DESIGN

A prospective observational study in which the estimate of nutrient intake and serum samples were obtained before the final outcome of pregnancy was known. A second part of the investigation was a cross-sectional comparison of magnesium status of normal pregnant women and women with certain pathological pregnancies.

SETTING

Antenatal clinic associated to the University Clinic of Obstetrics and Gynaecology, University of Aarhus, Denmark.

SUBJECTS

1203 consecutive women in the 30th week gestation were invited to participate in the study, 991 (82.4%) accepted and records for 965 (80.2%) were available for analysis.

DATA

Food intake data were collected by a combination of a self administered questionnaire and a structured interview of a dietary history type. Serum samples were obtained from blood withdrawn in the 30th and 37th week gestation. Obstetric data were collected from the midwifery and hospital records. For a second part of the investigation, biopsies from the uterus and the abdominal rectus muscle were obtained from women delivered by caesarean section.

RESULTS

In the women with normal pregnancies and in the three groups of pathological pregnancies (pre-eclampsia, SGA-infants and preterm labour) the average magnesium intake was within the range of 200 to 208 mg per 1000 kcal per day (SD 32) and there were no differences between the groups. Neither were differences in serum magnesium observed. Birthweight for gestational age was not influenced by magnesium intake. No differences in magnesium status as assessed by determination of magnesium content in muscle biopsies were found between the normal pregnancies and women with pre-eclampsia, SGA-infants or preterm labour.

CONCLUSION

The intake of magnesium seemed adequate, and pre-eclampsia, SGA-infants, or preterm labour did not seem associated with a low dietary intake of magnesium or magnesium deficiency. Routine magnesium supplementation during pregnancy is not recommended for populations of relative good socio-economic status.

Nutrition of women in anticipation of pregnancy

A causal connection between maternal nutrient intake and birth outcome is not universally accepted. In this paper further empirical support is provided, particularly in relation to the impact of maternal nutrition around the time of conception or very early in pregnancy. It is argued that the hypothesis that maternal nutrition has no connection with birthweight is very easily refuted. It is suggested that there should be a new category of recommended dietary allowances; "women in anticipation of pregnancy". The diet of 513 pregnant London women were recorded for 7 days during the first trimester of their pregnancy. Birthweight and nutrient intakes were found to be significantly correlated but only over the lower half of the birthweight range. The optimum birthweight range with the lowest perinatal and infant mortalities is 3,500-4,500 g and it is suggested that the nutrient intake of th 165 women who had babies in this optimum weight range provide tentative values for nutrient intake recommendations in anticipation of pregnancy, but are not claimed to be representative. The need for adjustments of recommendations for the individual, for example for a low body mass index, is discussed. A body mass index of 24 kg/m2 is recommended based on the median of the 165 women.