Midterm 2 Section 6 Flashcards
Weeks of gestation
first trimester: 12 weeks or less
second trimester: 13-28 weeks
third trimester: 29-delivery
preterm babies:20-36 weeks
term babies: 37+ (40 weeks is typical)
post 40 weeks requires medical intervention
placenta anatomy
metabolically active organ that connects baby and mother, blood never mixes
Fetal blood vessels project into placenta, in pool of mother’s blood coming from outer side of placenta
Fetal veins transport excreted products back to mother for external excretion
Fetus is entirely dependent on this system for respiration, nutrition and excretion
placenta functions
supply of nutrients and waste-removal system
produces hormones that maintain pregnancy and prepare body for lactation such as lactogen, estrogen and progesterone
progesterone - growth of uterus and block contractions
estrogen peaks towards the end of pregnancy and also helps uterus and fetus grow but stimulates contractions
lactogen adapts metabolic state of mom to to feed baby
when is the blastocyst implanted?
when is a fetus considered living?
when should the neural tube be closed by?
after 1 week post conception
after 11 weeks
6 weeks
when is the critical period of development?
first 2-3 months
folic acid fortification reduced neural tube defects from?
4 out of 1000 to .4 out of 1000
energy requirements per trimester
first trimester - nothing additional
second trimester -340 kcal extra
third trimester - 450 kcal extra
carbohydrates - 175g daily, 135g minimum
protein DRI during pregnancy
fat recommendations
25g additional per day
additional omega 3/6 including 200mg DHA per day
5oz fish per week (2 servings)
tuna to choose
tuna UL for pregnant women
low mercury fish
light tuna has lower mercury than white albacore tuna
not more than 300g (2 cans) of albacore tuna per week
small fish and seafood
calcium and iron DRI for pregnancy
same calcium DRI because absorption doubles during pregnancy
iron absorption increases 3x because fetus takes priority over mother’s needs
vitamin A during pregnancy
DRI is reduced to avoid teratogenic effects
at risk births
young women, many previous pregnancies, short intervals between pregnancies, history of trouble pregnancies, chronic disease, socioeconomic status, smoking, drugs, multiplies, weight gain too high or too low during pregnancy
risks related to weight prior to conception
underweight: increased pre-term and infant deaths
overweight/obese: gestational diabetes, large babies, gestational hypertension, complications for mother, health risks like heart problems for infants
weight gain recommended for BMI categories
under weight <18.5 gain 28-40lb
healthy 18.5-24.9 gain 25-35
overweight 25-29.9 gain 15-25
obese >30 gain 11-20
weight gain patterns
healthy: 3.5 lbs first trimester, 1lb per week after that
underweight: 5 lbs first trimester, 1lb per week after
overweight: 2lbs first trimester, 2/3lb per week after
components of weight gain during pregnancy
increased breast size, increased fluid, placenta, increased blood, amniotic fluid, infant, uterus and uterine muscle growth
what is considered a small size baby?
preterm or 5 1/2 lbs or less
higher risk of complications
gestational diabetes
can develop during 2nd half of pregnancy
leads to complications during labor, high infant birth weight, increased risk of type II later in life
hypertension in the mother
Preeclampsia
existing hypertension: risk of heart attack, stroke
risk of low weight birth and stillbirth
gestational hypertension: second half of pregnancy
preeclampsia: gestational hypertension with protein in the urine, diminished blood flow decreases fetal development, can progress to eclampsia (risk of mother convulsions and death)
treatment is to induce birth before it becomes eclampsia
risks for older birth
older father: risk of preterm, LBW, medical problems and ventilation needs
older mother: chronic conditions, maternal death rates, preterm birth, LBW and amniocentesis recommended over age 35 to do genetic testing on amniotic fluid
smoking during pregnancy risks
other things to avoid during pregnancy
decreased bloodflow to infant, decreased lung growth, sudden infant death syndrome, reduced brain size
mercury, lead, drugs, alcohol, herbal supplements, over the counter drugs
food borne illness in pregnancy
Listeria can cause miscarriage or impact brain/vital organ development
No soft cheeses, pasteurized products, washed produce, uncooked meats or fish, paté, refrigerated smoked seafood