Nutrition and Micronutrients in Pregnancy

1
Nutrition and Micronutrients in Pregnancy

• Advances in Maternal and Neonatal Health

2
Evidence of Nutritional Intervention Effectiveness

• Maternal malnutrition
• Folate
• Iron
• Iodine
• Vitamin A
• Zinc
• Calcium

3
Maternal Malnutrition and Pregnancy Outcome

• Severe nutritional deprivation (Netherlands
  194445)
• Birth weight significantly influenced by
  starvation
• Perinatal mortality rate not affected
• No increase incidence of malformation
• In healthy women, state of near starvation is
  needed to affect pregnancy outcome
• Severe nutritional deprivation (Netherlands
  194446)
• Periconception Decreased fertility, increased
  neural tube defect
• 1st trimester Increased stillbirths, preterm
  births, early newborn deaths
• 3rd trimester Low birth weight, small for
  gestational age, preterm birth

Cunningham et al 1997 Susser and Stein 1994.
4
Maternal Malnutrition and Pregnancy Outcome
(continued)

• Dietary restriction trials in pregnant women
• High weight for height or high weight gain
• Inconclusive results to demonstrate or exclude
  effect on fetal growth or any significant effect
  on other outcomes
• Mixed result with nutritional supplementation
  trials
• High protein No evidence of benefit on fetal
  growth
• Balanced protein and energy minimal increase in
  average birth weight (30 g) and small decrease
  in incidence of small for gestational age
  newborns
• Women manifesting nutritional deficits can
  benefit from a balanced energy/protein
  supplementation

Enkin et al 2000 de Onis, Villar and Gülmezoglu
1998.
5
Folic Acid

• Strong evidence that folic acid prevents
  preconceptionally recurrent and first occurent
  neural tube defects
• Increasing evidence that folic acid reduces risk
  of some other birth defects
• Improves the hematologic indices in women
  receiving routine iron and folic acid
• USPHS/CDC recommends for US women
• 400 ?g/day All women in childbearing age
• 1 mg/day Pregnant women
• 4 mg/day Women with history of neural tube
  defect deliveries take folic acid 1 month prior
  to conception and during first trimester

Czeizel 1993 Czeizel and Dudas 1992 Mahomed et
al 1998 MRC Vitamin Study Research Group 1991.
6
Nutritional Supplementation and Anemia

• WHO definition of severe anemia Hemoglobin lt 7
  g/dL
• Level of risk
• Moderate anemia (Hgb 711 g/dL) Not increased
• Severe anemia Significant risk
• Severe anemia associated with
• Low birth weight newborns
• Premature newborns
• Perinatal mortality
• Increased maternal mortality and morbidity

7
Anemia and Obstetrical Hemorrhage

• Anemia does not cause obstetrical hemorrhage
  (even severe anemia)
• Etiology of obstetric hemorrhage
• Early pregnancy Abortion complications
• Mid/late pregnancy to delivery Previa,
  abruption, atony, retained placenta, birth canal
  laceration
• Primary factors affecting outcome
• Rapid intervention to prevent exsanguination
• Availability of skilled provider, drugs, blood
  and fluids
• There is no evidence that high levels of
  hemoglobin are beneficial in withstanding a
  hemorrhagic event.

Enkin et al 2000 Mahomed 2000a.
8
Iron Supplementation

• Iron requirements
• Average non-pregnant adult
• 800 ?g iron lost/day
• 500 ?g iron lost/day during menses
• Pregnant woman Increased need
• Expanded blood volume
• Fetal and placental requirements
• Blood loss during delivery
• Routine vs. selective iron supplementation
• Prevalence of nutritional anemia
• Routine iron and folate supplementation where
  nutritional anemia is prevalent
• Recommended dose 60 mg elemental iron 5 ?g
  folic acid

Mahomed 2000b WHO 1994.
9
Iodine Supplementation

• Iodine deficiency is a preventable cause of
  mental impairment
• Iodine supplementation and fortification programs
  have been largely successful in decreasing iodine
  deficiency conditions
• Population with high levels of mental retardation
  (e.g., some parts of China)
• Supplementation may be effective at preconception
  up to mid-pregnancy period
• Form of iodine supplementation (iodinating food
  or oral/injectable iodine) depend on
• Severity of iodine deficiency
• Cost
• Availability of different preparation

Enkin et al 2000 Mahomed and Gülmezoglu 2000.
10
Vitamin A

• Indications for vitamin A supplementation
• Vertical transmission of HIV (ongoing)
• Infant survival
• Maternal anemia Positive interaction with iron
  in reducing anemia
• Infection
• Maternal mortality
• Vitamin A vs. placebo RR 0.60 (0.370.97)
• Beta-carotene vs. placebo RR 0.51 (0.300.86)
• Potential adverse effects of Vitamin A and
  related substances
• Total daily dose gt 10,000 IU before 7th week of
  gestation associated with birth defects
  craniofacial, central nervous system, thymic
  cardiac
• Overall effectiveness and safety of vitamin A
  supplementation needs to be evaluated

Rothman et al 1995 Suharno et al 1993 West et
al 1999.
11
Other Micronutrients Calcium

• Association between reduction in pregnancy
  induced hypertension (PIH) and calcium
  supplementation
• Reduction of incidence of PIH
• Routine supplementation likely beneficial in
  women at high risk of developing PIH or have low
  dietary calcium intake
• High calcium doses (2 g/day) not associated with
  adverse events
• Need adequately sized and designed trials in
  different settings to confirm beneficial effects
• Recommend increase in calcium intake through diet
  in women at risk of hypertension or low calcium
  areas

Bucher et al 1996 Kulier et al 1998
Lopez-Jaramillo et al 1997.
12
Calcium Supplementation Objective and Design

• Objective To assess effects of calcium in
  prevention of hypertensive disorders of pregnancy
• Methods Meta analysis of randomized controlled
  trial
• Outcomes
• Mothers Hypertension /- proteinuria, maternal
  death or serious morbidity, abruption, cesarean
  section, length of stay
• Newborns Preterm delivery, low birth
  weight/small for gestational age, neonatal
  intensive care unit admission, length of stay,
  still birth/death, disability, hypertension

Atallah, Hofmeyr and Duley 2000.
13
Calcium Supplementation Results

• Mothers
• Hypertension/-proteinuria
• Less hypertension RR 0.81 (0.740.89)
• Less pre-eclampsia RR 0.70 (0.580.83)
• Better if low calcium intake, high risk
• Newborns
• Low birth weight RR 0.83 (0.710.98), best for
  women at highest risk
• Chronic hypertension RR 0.59 (0.390.91)
• No difference in preterm delivery, neonatal
  intensive care unit admission, stillbirth, death

Atallah, Hofmeyr and Duley 2000.
14
Calcium Supplementation Conclusions

• Calcium decreases risk of hypertension,
  pre-eclampsia, low birth weight, and chronic
  hypertension in children
• Recommend for high risk women with low calcium
  intake, if pre-eclampsia is important in the
  population
• Calcium has other health benefits not related to
  pregnancy
• Maintaining bone strength
• Proper muscle contraction
• Blood clotting
• Cell membrane function
• Healthy teeth

Atallah, Hofmeyr and Duley 2000.
15
Summary of Nutritional Review Findings

• Evidence of nutritional intervention
  effectiveness
• Iron supplementation
• Periconceptional folic acid intake
• Iodine use
• Balanced energy/protein supplementation
• Calcium
• Confirmatory studies to examine effectiveness
• Vitamin A
• Zinc

16
References

• Atallah AN, GJ Hofmeyr and L Duley. 2000. Calcium
  supplements during pregnancy for prevention of
  hypertensive disorders and related problems
  (Cochrane Review), in The Cochrane Library, Issue
  3.
• Bucher HC et al. 1996. Effect of calcium
  supplementation on pregnancy-induced hypertension
  and preeclampsia a meta-analysis of randomized
  controlled trials. JAMA 275(4) 11131117.
• Cunningham FG et al. 1997. Williams Obstetrics,
  20th ed. Appleton Lange Stamford, Connecticut.
• Czeizel AE. 1993. Controlled studies of
  multivitamin supplementation on pregnancy
  outcomes. Ann N Y Acad Sci 678 266275.
• Czeizel AE and I Dudas. 1992. Prevention of the
  first occurrence of neural-tube defects by
  periconceptional vitamin supplementation. N Engl
  J Med 327 (26) 183235.
• de Onis M, J Villar and M Gülmezoglu. 1998.
  Nutritional intervention to prevent intrauterine
  growth retardation Evidence from randomized
  controlled trials. Eur J Clin Nutr 52(Suppl 1)
  S83S93.

17
References (continued)

• Enkin M et al. 2000. A Guide to Effective Care in
  Pregnancy and Childbirth, 3rd ed. Oxford
  University Press Oxford.
• Kulier R et al. 1998. Nutritional interventions
  for the prevention of maternal morbidity. Int J
  Gyn Obstet 63 231246.
• Lopez-Jaramillo P et al. 1997. Calcium
  supplementation and the risk of preeclampsia in
  Ecuadorian pregnant teenagers. Obstet Gynecol
  90(2)162167.
• Mahomed K. 2000a. Iron supplementation in
  pregnancy (Cochrane Review), in The Cochrane
  Library. Issue 4. Update Software Oxford.
• Mahomed K. 2000b. Iron and folate supplementation
  in pregnancy (Cochrane Review), in The Cochrane
  Library.Issue 4. Update Software Oxford.
• Mahomed K and A Gülmezoglu. 2000. Maternal iodine
  supplements in areas of deficiency (Cochrane
  Review), in The Cochrane Library. Issue 4. Update
  Software Oxford.

18
References (continued)

• Mahomed K et al. 1998. Risk factors for
  pre-eclampsia among Zimbabwean women maternal
  arm circumference and other anthropometric
  measures of obesity. Paediatr Perinat Epidemiol
  12 253262.
• Medical Research Council Vitamin Study Research
  Group. 1991. Prevention of neural tube defects
  results of the Medical Research Council Vitamin
  Study. Lancet 338 (8760)131137.
• Rothman KJ et al. 1995. Teratogenicity of high
  vitamin A intake. N Engl J Med 333 (21)
  13691373.
• Suharno D et al. 1993. Supplementation with
  vitamin A and iron for nutritional anaemia in
  pregnant women in West Java, Indonesia. Lancet
  342 13251328.
• Susser M and Z Stein. 1994. Timing in prenatal
  nutrition A reprise of the Dutch famine study.
  Nutrition Reviews 52 (3) 8494.
• West Jr. KP et al. 1999. Double blind, cluster
  randomised trial of low dose supplementation with
  vitamin A or beta carotene on mortality related
  to pregnancy in Nepal. Br Med J 318 570575.