Influence of mineral and vitamin supplements on

pregnancy outcome

Presented by: Nabiilah Naraino Majie & Joorawon Svenia

Date: 26/01/16

• Introduction• Methods• Minerals

– Iron, calcium, magnesium, zinc, selenium• Vitamins

– Vitamin A, B-Complex (B1,B6), folate, B12,C,E & D• Multiple micronutrients• Comments • Conclusion

Table of Content

Introduction• Nutrient metabolism and energy requirements should be

continuously and physiologically adjusted during pregnancy as the pre-pregnancy nutritional status affects maternal health and fetal growth.

• Fetal growth is mainly affected by low pre-pregnancy body mass index and low gestational weight gain.

• Malnourished women have increased risk for fetal disorders and nutrition of pregnant women is controlled.

• Mineral and vitamin supplements are usually given to prevent fetal diseases.

• Since deficiencies in minerals and vitamins influence pregnancy outcome, indications for nutritional support were investigated.

Methodology• Data was screened non-systematically

throughJournals about nutritionObservational studiesMeta-analysisRandomised controlled trialsReviews

MINERALS• Minerals are chemical elements required by humans’

body to maintain physical health and life functions.• Classified into major (macrominerals) and trace

elements.• Major minerals sodium, chloride, potassium,

calcium, phosphorus and magnesium.• Trace elements iron, zinc, iodine, selenium, copper

and fluorine. These are needed in smaller amounts.

Iron• Compulsory for haemoglobin synthesis and proper

functioning of organs.• Being the most prevalent nutrient deficiency in the

world, lack of Fe affects more than 50% of pregnant women.

• Major impact of this deficiency is the inhibition of fetal growth as neonatal Fe depends on status of maternal Fe.

• This leads to anaemia, intrauterine growth retardation, neonates small for gestational age and oxidative damage to fetal erythrocytes. Cortisol production as well as maternal and fetal stress are increased.

Iron• Prolonged gestational Fe deficiency leads to cognitive

and behavioural problems in childhood.• Fe is supplemented in case of low haemoglobin and

plasma ferritin.• Surplus of Fe increases the risk for gestational DM and

preterm delivery.• Sources include red meats, dark green leafy

vegetables and dried fruits.

Calcium• Essential for bone development, muscle and cell membrane

functions, nerve impulse transmission and blood coagulation.• Ca demand is increased during pregnancy as it is needed for

mobilisation from skeleton and doubling of intestinal absorption.

• Hypocalcaemia causes pre-eclampsia and intrauterine growth retardation but it occurs rare in pregnant women.

• However, statistics reveals that low birth weight can be associated with low intake of milk and vitamin D during pregnancy.

• Sources: milk and dairy products.

Magnesium• Common enzyme cofactor and activator, Mg is needed for

muscle contraction, nerve transmission and protein manufacture.

• Mg deficiency during pregnancy interrupts fetal growth and development which eventually causes haematological and teratogenic harm.

• Diabetic pregnant women with hypomagnesaemia increases the risk for both maternal and fetal hypoparathyroidism and hypocalcaemia.

• Sources: nuts, green leafy vegetables and chocolates.

Zinc• Required for the activity of about 100 enzymes, Zn has also

antioxidant properties, protects immune system and is involved in embryogenesis and growth.

• Gestational Zn deficiency affects fetal growth which can lead to severe teratogenic effects.

• Fetal demand for Zn occurs through absorption in intestine but the transfer of Zn depends on the maintenance of maternal Zn concentration.

• Zn absorption is altered by high intake of Fe, GI dysfunction and cereal-based diets rich in phytate.

• Excess of Zn during pregnancy can increase birth weight of neonates.

• Sources: meat, poultry, fish and whole grains.

Selenium• Requested for its good antioxidant properties, Se protects the

immune and reproductive systems.• Low level of Se during pregnancy is associated with pre-

eclampsia, intrauterine growth retardation and abortion.• Studies have proved that Se supplementation decreases the

prevalence for pre-eclampsia.• Sources: seafood, grains and meat.

VITAMINS• Organic compounds

– Fat soluble or water soluble• Required in small quantities• Support of normal physiologic functions• Humans do not biosynthesize enough to meet the needs of the

body• 20-30% of pregnant women suffer from vitamin deficiency• About 75% vitamin deficiency was observed without

prophylaxis• In a study, despite vitamin supplementations, reduced level of

vit A, B6, B3, B1, and B12 was observed during all pregnancy trimesters.

Vitamin A• Fat soluble vitamin essential for the following:

– Gene regulation, cell differentiation, proliferation and growth, innate and adaptive immune system, maintenance of mucosal surfaces, intestinal iron uptake, haematopoiesis, vision and reproduction.

• Vit A deficiency is prevalent in developing countries while overdose is mostly common in developed countries.

• Vit A is beneficial in right amount while teratogenic in high amount– The recommended dose is 5000 IU/day; – High doses (8000-10000 IU/day) may not result in malformations

• Vit A supplementation lead to improvement in birth weight and growth is observed among infants born to HIV-infected women due to enhanced immunity.

Vitamin B1-Thiamine• Water soluble• Acts as coenzyme essential in metabolism and lipid &

nucleotide synthesis• Deficiency is more common in developing countries

especially during pregnancy which may result in impairment of brain development and impair fetal growth

• Higher level are encountered in fetus than in maternal blood due to specific active placental transport systems.

• However, there is lack of data on the role of Vit B1 in pregnancy.

Vitamin B6• Also known as pyridoxine, pyridoxal & pyridoxamine• Water soluble- works as coenzyme in protein metabolism in

the development of CNS• Deficiencies do not occur alone but with deficiencies of B-

Complex vitamins– Pre-eclampsia, gestational carbohydrate intolerance, hyperemesia,

gravidarum, & neuronal disease of infants.• Clinical benefits of Vit B6 supplementation in pregnancy has

not been detected– One trial suggested protection against dental decay.

Folate• Water soluble• Co-enzymatic role in carbon metabolism and in synthesis of

DNA, RNA and certain amino acids.• Deficiency is prevalent in developing countries

– 25% of pregnant women in India– Lead to congenital malformations and complications in pregnancy

• Daily supplemental dose of 400ug/day is recommended– Higher doses (5mg) is recommended in conditions such as obesity,

diabetes & epilepsy• Study showed that folate supplementation in pregnancy

resulted in reduced congenital anomalies

Vitamin B12-Cobalamine• Important support for erythropoiesis• Increased prevalence in low plasma B12 during pregnancy• Long term vegetarian pregnant women have an increased risk

of Vit B12 deficiency.• Decline in plasma cobalamine despite an adequate diet

resulting in –ve fetal outcome– Alterations in haptocorrin-bound cobalamine– Impairment of intestinal absorption

• Strong association between fetal and maternal plasma at delivery– Maternal B12 levels affects fetal vitamin level at birth– Low level reduced fetal growth

Vitamins C & E• Vit C (water-soluble; ascorbic acid) and Vit E (fat-soluble; a-

tocopherol) are powerful antioxidants for prevention & treatment of pre-eclampsia (PE) caused by oxidative stress

• Increased Ox. markers and decreased in Vit C (<85mg) & E in PE

• From a report Use of any antioxidants lead to 39% decreased risk of PE

• From other survey– Use of Vit C & E suppl. in pregnancy does not reduce risk of PE– Vit E may increase incidence of PE due to ability to induce Th1 cytokines

(pro-inflammatory)– Use of Vit E may cause gestational hypertension, LBW, placental ischemia

• Vit C may be advantageous but Vit E is not recommended

Vitamin D• Fat-soluble; Important role in immune function, cell

differentiation, bone growth & reduction of inflammation.• Essential for calcium homeostasis & reduction of chronic

diseases.• Biologically inactive metabolised to active form

– 25-hydroxyvitamin [25(OH)D]• 40% African American women and 4% caucasian-non-hispanic

women have low plasma Vit D conc.• Deficiency is associated with osteomalacia, poor fetal and

infant skeletal growth & tooth mineralisation.• No evidence in general suppl. has been found except that it

improve neonatal handling of Ca in population at risk.

Multiple micronutrients (MMN)• Micronutrient deficiencies are caused due to

– Unavailability of adequate food quality– Cultural differences– Seasonal variations– Poverty & infection in a population

• Several studies showed improved pregnancy upon use of MMN e.g. reduced LBW.

• Large scale blood tests are scarce thus little are known about the range & extent of nutrient deficiencies

• Evidence from studies shows that prevalent deficiencies of Ca, Fe, Vit D, A, Zn and folate are most common in developing countries.

Comments• Vitamin suppl. considered solely as health promoting• Deficiencies may result in morbidity

– Negative consequences to fetus & child health– Effect of vitamins in pregnancy is poorly understood but vit treatment can

be curative• Quantification of individual food component are difficult and

unreliable– Non-homogenous population– MMN may contain unnecessary and harmful overdoses– Nutrient interactions are numerous– Despite antioxidant properties of vit C & E; may lead to complication

• MMN important to prevent adverse pregnancy outcome are: folic acid, Zn, Fe.

Conclusion• Substitution therapy and supplementation may be beneficial

during pregnancy but deficiencies should be sought• Pre- and early pregnancy folate suppl. has been confirmed

via reliable studies• Fe treatment in Fe deficiency also has beneficial effects• Vegetarian pregnant women lacks Vit B12, thus suppl. is

needed.• Vit D and C are beneficial in PE treatment but Vit E is not

recommended.

References• ANON, 2014. Minerals: Their functions and sources-

Topic overview. WebMD [online]. Available from: http://www.webmd.com/vitamins-and-supplements/tc/minerals-their-functions-and-sources-topic-overview [Accessed on 22 January 2016].

• HOVDENAK, N., HARAM, K., 2012. Influence of mineral and vitamin supplements on pregnancy outcome. European Journal of Obstetrics & Gynecology and Reproductive Biology; 164(2012), 127-132.