Lifecycle Exam 1 Preconception - Lactation

energy availability in RED-S

energy intake is insufficient relative to exercise and needs

Which DRI value best answers the question: What is the amount of nutrient needed to prevent deficiency in almost all healthy individuals?

RDA

Before pregnancy, iron status is important because iron deficiency can lead to what risk during pregnancy?

iron-deficiency anemia and low infant iron stores

What waist circumference threshold is associated with increased cardiometabolic risk for women?

>35 in

What is the average menstrual cycle length?

28 days

What can negative energy balance impair?

hypothalamic GnRH signaling

What results in hypothalamic GnRH signaling is impaired?

downstream hormone signaling is altered, possibly causing anovulation, cycle irregularity, or functional hypothalamic amennorhea

secondary amenorrhea

absence of periods after having a cycle

RED-S

relative energy deficiency in sports

RED-S impact on females

menstrual dysfunction, lower estrogen, impaired bone formation/repair, fertility concerns

RED-S impact on males

reproductive hormone disruption, lower testosterone, libido/sperm effects, bone and performance concerns

RED-S and amenorrhea are relevant to

bone health

average length of menstrual cycle

28 days

in women GnRH from hypothalamus stimulates

pituitary

in women FSH stimulates

follicle development

in women LH surge stimulates

ovulation

in women estrogen stimulates

endometrial growth and bone effects

in women progesterone supports

luteal phase and endometrium

in men GnRH stimulates

pituitary FSH and LH

in men FSH supports

sertoli cells and spermatogenesis

in males LH stimulates

interstitial (Leydig) cells that stimulate testosterone

in men testosterone supports

sperm maturation and reproductive function

Inadequate and excessive body fat is associated with

reduced fertility in males and femaless

What nutrition factors can influence fertility?

dietary patterns, nutrient intake, calorie intake and body fat

Underweight and weight loss can be associated with

lower reproductive hormone concentrations, anovulation and amenorrhea

What can impair hypothalamic GnRH signaling?

negative energy balance

amenorrhea

absence of menstruation in someone that has never had a period

secondary amenorrhea

absence of periods in a person that has had them

How does male obesity affect hormones?

lower testosterone and higher estrogen

What deficiency can impair sperm quality and function?

zinc

Heavy metal exposure is associated with

lower testosterone and abnormal sperm production/motility

What mineral deficiency before pregnancy can impact the infants stores?

iron

Iron stores should be assessed and adequate ideally

before pregnancy

Early pregnancy hormones

estrogen and progesterone promote insulin and glycogen formation

later pregnancy hormones

placenta hormones reduce maternal insulin

pregnancy weight gain for BMI < 18.5

28-40 lbs

pregnancy weight gain for BMI 18.5-24.9

25-35 lbs

pregnancy weight gain for BMI 25-29.9

15-25 lbs

pregnancy weight gain for BMI > 30

11-20 lbs

protein requirements for pregnancy

0.8g/kg + 25 g

fatty acids relevant to fetal development

DHA and EPA

What micronutrients are important for healthy blood development during pregnancy?

iron, folate, B12

What micronutrients are important for neural development during pregnancy?

folate, B12, iodine, choline

What micronutrients are important for bone and mineral development during pregnancy?

calcium and vitamin D

chronic hypertension

present before pregnancy or before 20 weeks

gestational hypertension

occurs first during pregnancy

preeclampsia

pregnancy-specific syndrome; can affect multiple maternal organs

Alveoli contain secretory cells that produce

milk

What cells surround the alveoli and contract to move milk into the ducts?

myoepithelial

Lactogenesis I

milk formation begins during pregnancy, around 16 weeks

Lactogenesis II

major increase in milk production after birth; milk comes in during the early postpartum period

Lactogenesis III

established lactation; milk production becomes primarily regulated by milk removal and infant demand

What hormone stimulates milk production?

prolactin

What is prolactin released in response to?

suckling and nipple stimulation

What does oxytocin do in breastfeeding?

causes myoepithelial contraction and milk ejection

What is central to establishing and maintaining milk supply?

frequent and effective milk removal

What does milk production respond to?

how effectively, how often and how long milk is removed

colostrum

first milk during the early days postpartum

composition of colostrum

high in protein, minerals, immunoglobins and lactoferrin

When does colostrum production begin?

lactogenesis I, midpoint of pregnancy

When is mature milk produced?

lactogenesis II and III, after infant and placenta are delivered

mature milk composition

high CHO and fat

How many calories is human milk?

20 cal/oz

What are infant allergies a reaction to?

mom’s diet, not her breastmilk

What vitamin is human milk low in?

vitamin K

What vitamin is a concern when there’s poor maternal status, vegan mom, or malabsorption?

vitamin B12

What degree should a babys mouth be open at when breastfeeding?

150 degrees

What are early hunger cues in infants?

hand-to-mouth activity, sucking, and head turning/rooting

What is a late hunger cue?

crying

How many calories does milk expenditure cost in the first 6 months?

540 kcal/day

How many calories does milk expenditure cost during 7-12 months?

380 kcal/day

What is a common but not normal problem during breastfeeding?

cracks, fissures, or pain throughout a feeding

What can cause delayed or difficult milk letdown?

stress, pain, and persistent ineffective removal

What can happen if there is an oversupply or forceful letdown of milk?

infant may cough, choke, gulp, pull away or become fussy

Mastitis

milk gets stuck in breast and leads to infection with flu-like symptoms, redness, swelling, fever and requires antibiotic

What does medication risk of transfer to breastmilk depend on?

drug properties, maternal dose/duration, milk concentration, infant absorption and clearance, infant age, feeding pattern, and health

galactagogue

food, herb, or medication that affects breast milk production

What are common galactagogues?

fenugreek, goat’s rue, and milk thistle

caffeine intake during breastfeeding

moderate intake is tolerated by most infants

How do babies excrete bilirubin?

pooping

What can help lower bilirubin in babies?

light exposure and eating enough to poop regularly

breastfeeding jaundice

occurs within first week, associated with poor milk transfer, low caloric intake, or infrequent feeding

breast milk jaundice

occurs within 2-3 weeks, happens despite adequate feeding and milk transfer

galactosemia

infant can’t break down galactose, breastfeeding is contraindicated

How long can fresh breastmilk sit out at room temperature?

4 hours

How long can breastmilk last in the fridge?

4 days

How long can breastmilk last in the freezer?

6 months

If a baby doesn’t finish a bottle of formula, how long until it can’t be used?

2 hours

How long is exclusive breastfeeding recommended?

6 months