Micronutrients & PregnancyJosie Mirabelli, UWGB Intern

Objectives

● Overview of micronutrients

● Healthy pregnancy diet

● 3 key micronutrients in pregnancy

● Research review

Overview of Micronutrients

● Vitamins and minerals

● Vital to healthy development, disease prevention, and wellbeing

● Primarily obtained from diet and supplementation

● Deficiencies → devastating consequences

Healthy Pregnancy Diet

● Promote baby’s growth and development

● Basic principles: plenty of fruits, vegetables, whole grains, lean protein,

healthy fats

● Daily prenatal vitamin (begin 3 months before conception)

● 3 key micronutrients: calcium, folate, iron

Calcium

● Builds strong bones and teeth

● Aids in circulatory, muscular, and nervous system function

● Decrease risk of preeclampsia, preterm birth, low birth weight

● Good sources: dairy, broccoli, kale, fortified fruit juices and cereals

● 1,000 mg/day

Folate

● Helps prevent neural tube defects

● Folic acid = synthetic form in supplements and fortified foods

● Decrease risk of premature birth

● Good sources: fortified cereals, leafy green vegetables, citrus fruits, dried

beans and peas

● 400 to 1,000 mcg/day

Iron

● Increase blood production to supply oxygen to the baby

● Need double the amount during pregnancy

● Decrease risk of iron deficiency anemia

● Good sources: lean meat, poultry, fish; iron-fortified breakfast cereals,

beans, vegetables

● 27 mg/day

Article 1

Title: Calcium: A Nutrient in Pregnancy

Year Published: 2017

Objective: Determine the effects of calcium intake on maternal and infant

health.

Kumar, A., & Kaur, S. (2017). Calcium: A nutrient in pregnancy. The Journal of Obstetrics and Gynecology of India, 67(5), 313-318.

Article 1: Overview

● Dependent Variables: preeclampsia, preterm birth, birth weight, infant

bone density

● Method: supplementing 0.5-2 grams calcium/day during pregnancy

● Studies: cohort, Cochrane review, randomized control trials

Article 1: Cohort Study - Preeclampsia and Preterm birth

● Participants: 524 healthy primigravidas

● Where: tertiary care hospital in North India

● Method: daily supplementation of 2 grams calcium/day between 12 & 15

weeks gestation

● Findings: 66.7% risk reduction of preeclampsia, risk for preterm delivery

decreased by 12.7%

Article 1: Cochrane Review - Preeclampsia

● Participants: 15,730 pregnant women, 13 trials

● Findings: Risk of preeclampsia reduced in those receiving calcium

Article 1: Randomized Control Trial - Birth Weight

● Participants: 510 healthy, Argentinian women <20 weeks gestation

● Two groups: placebo (n = 230), treatment group w/ 1.5 grams

calcium/day (n = 231)

● Findings: 15% decrease in low birth weight

Article 1: Randomized Trial - Infant Bone Density

● Participants: 256 women, before 22 weeks gestation

● Two groups: 2 grams calcium/day, placebo

● Measures: DEXA within first week of life

● Findings: total body mineral content much higher in treatment group

Article 1: Randomized Control Trials

Preterm Birth:

● 11 trials

● Findings: 24% decrease in

preterms births

Preeclampsia:

● 15 RCTs

● Findings: 52% decreased risk for

preeclampsia, significantly

reduced risk of maternal

mortality/severe morbidity

Article 1: Conclusion

Calcium supplementation for pregnant women with deficient intake offers

modest benefits in preventing preeclampsia and preterm births and improving

maternal and infant bone health.

Article 2

Title: Effect of continued folic acid supplementation beyond the first trimester of pregnancy on cognitive performance in the child: a follow-up study from a randomized controlled trial (FASSTT Offspring Trial)

Year Published: 2019

Objective: Determine the effect of folic acid supplementation during trimesters 2 and 3 of pregnancy on cognitive performance in the child.

McNulty, H., Rollins, M., Cassidy, T., Caffrey, A., Marshall, B., Dornan, J., Pentieva, K. (2019). Effect of continued folic acid Supplementation beyond the first trimester of pregnancy on cognitive performance in the child: A follow-up study from a randomized controlled trial (FASSTT OFFSPRING TRIAL). BMC Medicine, 17(1).

Article 2: Methods - Study Population

● Follow-up investigation: children with mothers previously in FASSTT Trial

● Criteria (mothers): healthy, pregnant, 18-35 years, took recommended

400 mcg folic acid/day

● Recruited from antenatal clinics 14th week gestation

● Randomly assigned:

○ 59 in treatment group (400 mcg folic acid/day)

○ 60 in placebo group

Article 2: Methods

FASST Offspring Trial Measurements:

● Cognitive tests

● Anthropometric measures

● Laboratory assessment

● Statistical analyses

Article 2: Methods - Cognitive Tests

7 years old:

● WPPSI-III: 40-50 minutes, full scale IQ

● Room: well-lit, ventilated, free from distractions

3 years old:

● BSITD-III

● Assess cognitive performance, communication, motor skills

Article 2: Methods

Anthropometric: height, waist, head circumference, body fat

Laboratory: non-fasting blood samples from mother at 14th and 36th

gestational weeks, umbilical cord blood at delivery

● Analyzed serum and RBC folate

Article 2: Methods - Statistical Analyses

● 3 years: 39 children, both groups

● 7 years: 43 children in each group

● Group differences analyzed with t tests

Article 2: Results

● 70 of 119 participants completed trial at 7 years

● 39 completed at 3 years (34 from 7 year group)

● No significant differences in general for maternal and child characteristics

between groups

Article 2: Results - Folate Biomarkers

● Serum and RBC folate significantly higher in FA groups

● Significantly higher folate concentrations in FA treatment group in

cord blood at delivery

Article 2: Results - Cognition

WPSI-III:

● Treatment group much higher in word reasoning; 13.3 vs. 11.9

● Folate status at 36 weeks → significant predictor for subsequent verbal IQ

BSITD-III:

● Treatment group much higher in cognitive domain

Both groups:

● Treatment groups had greater proportions scoring above median value

Article 2: Conclusion

Continued FA supplementation through second and third trimesters can

influence cognitive performance of child up to 7 years old.

Article 3

Title: The contribution of iron deficiency to the risk of peripartum transfusion: a

retrospective case control study

Year Published: 2020

Objective: Identify the prevalence of iron deficiency and anemia in pregnant

women that received peripartum transfusions relative to age-matched

non-transfused controls.

VanderMeulen, H., Strauss, R., Lin, Y., McLeod, A., Barrett, J., Sholzberg, M., & Callum, J. (2020). The contribution of iron deficiency to the risk of

peripartum transfusion: A retrospective case control study. BMC Pregnancy and Childbirth, 20(1).

Article 3: Methods

Type: retrospective case-control study

Where: Sunnybrook Health Sciences Centre in Toronto, Canada

Cases: obstetrical patients receiving peripartum transfusion

When: between January 2014 and July 2018

Article 3: Methods - Exclusion Criteria

● Explanation for anemia

● Pre-existing transfusion dependence

● Different hemoglobin targets for transfusion

● Majority prenatal care outside institution

Article 3: Methods - Data Collected● Demographic and laboratory

● Transfusion history

● Past medical history and dietary restrictions

● Median household income

● Delivery and perinatal outcomes

● Complete blood count and iron study history

Article 3: Methods - Secondary Objective

Determine rate of suboptimal care in pregnancy

● Unaddressed anemia

● Uncorrected iron deficiency or IDA

● Mild or moderate anemia

● Hb <90 g/L postpartum w/ uncorrected iron deficiency

Article 3: Methods - Descriptive Statistics

● Statistical Analysis Software (SAS)

● Predefined risk factors for iron deficiency, anemia, and transfusion

● Dependent variable: univariate logistic regression

● Multivariate logistic regression

● Odds ratio and 95% confidence interval

Article 3: Results - Demographics

● 169 of 18,294 women received transfusions

○ 24 exclusions

● = 145 cases, overall cohort of 290 patients

● Mean age = 33.1

Article 3: Results - Transfusion Metrics

Total = 359 units of RBCs

● 1 unit = 64 cases

● 2 units = 48 cases

● 3+ units = 33 cases

● 4 transfused antepartum, 141 at delivery or postpartum

Article 3: Results - Primary Outcome

● Iron deficiency or anemia in 103 cases, 74 controls

● Odds of moderate postpartum anemia with suboptimal care

significantly higher in cases

Article 3: Results - Iron Status

Iron Status Cases Controls

Iron Deficiency prior to Pregnancy

27 9

Iron Deficiency 72 62

Iron Deficiency Anemia 32 11

Oral Iron Replacement 51 37

IV Iron Therapy 24 3

Article 3: Results - Univariate Analysis

● Socioethnic factors: caucasian, social work involvement, low-income →

significant associations with odds of transfusion

● Women with anemia: 4x higher odds transfusion

● Cases: higher rates of IDA

● Vaginal delivery: lower odds transfusion

Article 3: Results - Multivariate Analysis

Factors associated with higher odds peripartum transfusion:

● Social work involvement

● IV iron supplementation

● Unplanned cesarean section

Article 3: Results - Maternofetal Outcomes

● Cases: more primary postpartum hemorrhage and bacterial

infections

● Babies with transfused mothers: higher rates fetal demise,

prematurity, LBW, and NICU admission

Article 3: Conclusion

Iron deficiency in pregnancy is common, under-recognized and

undertreated. There are implications for mothers and babies and

predisposes women to blood transfusions which may have severe

consequences for future pregnancies.

Summary of Research Findings

Calcium supplementation for pregnant women with deficient intake offers modest benefits in

preventing preeclampsia and preterm births and improving maternal and infant bone health.

Continued FA supplementation through second and third trimesters can influence cognitive

performance of child up to 7 years old.

Iron deficiency predisposes women to blood transfusions which may have severe consequences

for future pregnancies.

Implications for Practice

● Calcium supplementation should be recommended for women with low

dietary intake.

● Folic acid supplementation should be considered past the first trimester to aid

in cognitive performance.

● All pregnant women should be screened for iron deficiency early on for the

best outcome.

References

● M. (2019, December 19). Pregnancy diet: Focus on these essential nutrients. Retrieved April 15, 2021, from

https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/pregnancy-nutrition/art-200

45082

● Kumar, A., & Kaur, S. (2017). Calcium: A nutrient in pregnancy. The Journal of Obstetrics and Gynecology of

India, 67(5), 313-318.

● McNulty, H., Rollins, M., Cassidy, T., Caffrey, A., Marshall, B., Dornan, J., . . . Pentieva, K. (2019). Effect of

continued folic acid Supplementation beyond the first trimester of pregnancy on cognitive performance in the

child: A follow-up study from a randomized controlled trial (FASSTT OFFSPRING TRIAL). BMC Medicine, 17(1).

● VanderMeulen, H., Strauss, R., Lin, Y., McLeod, A., Barrett, J., Sholzberg, M., & Callum, J. (2020). The

contribution of iron deficiency to the risk of peripartum transfusion: A retrospective case control study. BMC

Pregnancy and Childbirth, 20(1).