Maternal Nutrition Flashcards
What does preconceptual mean?
1-3 months prior to conception
What does periconceptual mean?
Immediately prior to conception and early gestational phase
What is the first trimester?
0-13 weeks (most crucial for baby’s development)
What is the second trimester?
14-26 weeks
What is the third trimester?
27-40 weeks
What does preconceptual nutritional status influence?
Birth outcomes
Why does mother need to be at optimal nutritional status during the embryonic stage of fetal growth (weeks 2-8) and what is the problem with this?
- Nutrients primarily from maternal blood
- Critical period of development
- Often before the pregnancy is confirmed - 50% pregnancies are ‘unplanned’ so women may not be nutritionally ready for pregnancy
- Lack of certain nutrients may cause specific congenital abnormalities
Why is maternal nutrition important throughout pregnancy?
1) During pregnancy the maternal diet must provide sufficient nutrients to meet the mother’s usual requirements as well as those of the growing fetus and stores for use during the third trimester and lactation
2) Nutritional requirements during pregnancy to support fetal growth and development and expanding maternal tissues (incl. preparation for lactation)
3) > 90% fetal growth during 2nd half of pregnancy - nutrients stored in early pregnancy in preparation for rapid growth
4) Fetal nutrition in utero has a key role in the health of the newborn infant and throughout the lifecycle
What is the normal weight gain in pregnancy for a mother who is normal weight when they conceive?
12kg (mean weight gain in pregnancy) - but variation and SD is huge
What causes the weight gain in pregnancy?
1) Fetus
2) Placenta and amniotic fluid - variable depending on size of mother
3) Uterus and breasts - variable depending on size of mother
4) Blood
5) Extracellular fluid
6) Maternal fat stores - v variable
What is the consequence of inadequate gestational weight gain (GWG)?
Low birth weight
What are the consequences of excessive GWG?
1) Adverse maternal and neonatal outcomes
2) Postpartum weight retention - pregnancy can result in obesity of the mother
What guidelines are used for GWG recommendations?
- No UK evidence based GWG recommendations - use American guidelines
- IOM weight gain targets depending on BMI
- However not realistic for obese women
- Good to advise underweight women to put on weight
- Recommending to lose weight can lead to still birth (ketones)
When should how much weight be gained in pregnancy?
Normally 0.5-2kg of weight is gained during the first trimester of pregnancy and the remainder of the recommended weight gain is expected during the second and third trimesters
What are the risks associated with maternal obesity?
1) Gestational diabetes
2) Pre-eclampsia
3) Thromboembolism
4) C section
5) Stillbirth
6) Congenital malformation
7) Miscarriage
8) Haemorrhage
9) Infection
What is the mean optimal birth weight?
3.3kg
Is it necessary to eat for two in pregnancy?
- No - unless underweight
- Should only eat an additional 191 kcal/day in third trimester
- Also have reduced physical activity
- Weight loss not advised
Why is the neural tube vulnerable to preconceptual nutritional deficiencies?
Bc closure of the neural tube occurs very early in pregnancy (12 weeks)
What are the oral folate supplement recommendations in early pregnancy?
1) All women planning pregnancy should take 400 micrograms per day 8 (3) weeks pre-conception until 12 weeks post conceptually (need 20x more folic acid in first trimester/pre-conception) - if taking 5mg can mask B12 deficiency
2) If have had a child with a prior NTD, they should supplement 5mg of folic acid per day (if higher risk of NTDs)
What is folic acid critical for?
- It is critical in early pregnancy to protect against NTDs in the development fetus - should consume folic acid 8 weeks prior to conception
- It also prevents megaloblastic anaemia in later pregnancy