N393 Final Flashcards
How do hormones change in pregnancy?
Every woman has cycle with variation; same hormones responsible play key role in maintaining pregnancies upon conception and fertilization
The corpus luteum is endocrine structure(produces hormones) or gland formed in ovary at site where egg is released
If egg not fertilized, the corpus luteum goes away
If egg is fertilized, the CL transforms into endocrine organ that helps maintain pregnancy
We think CL and hormones released is responsible for morning sickness
CL is responsible until placenta is large enough to take over
Hormones
HCG
Estrogen
Progesterone
HCG
(Human Chorionic Gonadotropin)
Produced by developing conceptus and placenta
Is a positive feedback mechanism; tells CL to release larger quantities of sex hormones (estrogen and testosterone)
Basis of many pregnancy tests and lab tests
Prevent involution of corpus luteum
Estrogen
Produced by CL and Placenta
Enlargement of uterus, breasts, and external genitalia
Relax pelvic ligaments so body can accommodate larger growing organ of uterus and baby inside
Progesterone
Produced by CL
Role in nutrition of early embryo
Decreases uterine contractility (tells body to “chill out”)
Helps estrogen prepare breasts for lactation
Shown in graph how it increases and then drops off completely to allow labor
Formation of placenta
Formed from trophoblast cells around the blastocyst (fetal development tissues)
Placenta thickness between mom and baby is about 1 layer of cells in some places - think about this small barrier with pharmacology
Function of placenta
Diffusion: Primary way placenta works
Higher concentration to lower
Flow of blood through placenta
Mom has uterine arteries and veins that empty into middle sides (maternal sinuses)
Baby side has umbilical vein and umbilical arteries, getting what they need from diffusion
Nutrients
Waste is exchanged
Gases (CO2 and O2)
Body’s response to pregnancy: weight
Weight gain- average total: 24 lbs (by end of pregnancy) Fetus: 7lbs Placenta, amniotic fluid: 4 lbs Uterus: 2 lbs Breasts: 2 lbs Plasma volume: 6 lbs Fat: 3 lbs
Body’s response to pregnancy: Metabolism & Nutrition
Metabolism & Nutrition*
Basic metabolic rate increases 15% during later half of pregnancy
Providing nutrients to help baby grow
Placental stores of nutrients are needed to sustain fetal grown during the last months of pregnancy (a lot of moms worry about weight)
Body’s response to pregnancy: Breast Development
Starts in first few weeks of gestation; they are enlarging but not working or prepared to do milk portion of it
Hormones
estrogen, progesterone, prolactin oxytocin
Breast development Hormones
Estrogen: stimulates tissue to grow
Progesterone: stimulates tissue to grow; the ductules, lobes in breasts
Prolactin: stimulated production with baby eating/suckling (baby eats = prolactin levels rise = nipple stimulated = milk produced)
Oxytocin: responsible for let down or milk ejection and responsible for uterine contractions
Will help uterus return to size while breastfeeding
Body’s response to pregnancy: Kidney Function
Increased renal plasma flow and glomerular filtration rate
More fluid that all must go through kidneys
Very little is related to waste of fetus; babies would produce urine and would be in amniotic fluid, it is sterile
Majority of this is mom with increased plasma and fluid she needs to process
Body’s response to pregnancy: Circulatory
Mom’s cardiac output will increase 30-40% by 27th week of pregnancy; By end of pregnancy, 30% greater blood volume
Less RBCs in relation to blood volume may see resulting in dilutional anemia; not anemic, not decrease in hematocrit; in relation to everything going on, she will have/experience decrease in hematocrit
Moms will be monitored closely but in greater context it is just because mom has more plasma volume
Heart working harder to maintain the new volume
Body’s response to pregnancy: Respiratory
Respiratory- increased RR
20% increase in oxygen use by mother at term
May see higher RR taking vitals
Progesterone increases minute ventilation
Uterus presses abdominal content up against the diaphragm
Common complaints during pregnancy and anatomical reason why
Spine
Back pain, displaced center of gravity back pain
Intestines
Constipation, organ moved around
Bladder
Constant urination, bladder squished
Stomach
Gastric reflux/indigestion, change in pressure, no room to expand
Can’t eat as much, get full fast
Lungs
Can’t take deep breaths
Sleeping changes Needing to pee Needing to sleep on side Edema Extra fluid
Breast tenderness
Colostrum can be excreted for weeks
Falls
Increased risk for falls
Massive stretching
Heart should not enlarge
What to avoid during pregnancy (don’t need to know specifics)
Cigarettes, alcohol, illicit drugs, stimulants, Vitamin A at doses higher than 5,000 IU, Liver(?), herbal products, Dieting and skipping meals, Iodine, Limit certain fish, undercooked or raw fish, meat, etc.
Prenatal vitamins
Various products may not be equivalent/interchangeable; Content not standardized
Regulation as “supplement”
Potential compliance issues- health individuals may not appreciate need - Education!
Adverse effects
Nausea, vomiting, constipation (especially Fe- containing)
Take with food or in evening to
Constipation- hydration, fiber intake activity
Notes
Recommend reputable brand if OTC (may have prescription)
Stress on body - need supplement
Folic Acid Function
Cell division, DNA synthesis (makes DNA)
Neurodevelopment
FA goes through reduction with dihydrofolate reductase reduced to tetrahydrofolic acid and goes on to make amino acids
Folic Acid Use in Pregnancy
Start preconception (preferably in months before) Neural tube closure @ 18-26 days post conception Populations at risk for deficient (e.g., epilepsy, family history neural tube defect, etc)
Folic Acid Dose
Decreased neural tube defects Preconception & 1st trimester 400-800 mcg daily Different doses for certain increased risk groups Adverse effects Water soluble-few AE May mask deficiency of Vitamin B12
Iron Function
HB (70-80% of total body Fe); myoglobin; iron-containing enzymes
Other
Transferrin
Ferritin (storage iron pool)
Fe from degraded RBCs recycles (120 days)
As you take iron in, some immediately stored, some go through life cycle, as RBC dies it releases iron again and it will keep going through cycle
Loss largely due to blood loss
Iron deficiency anemia
Fe requirements
Increased RBC production
Iron - Uses in pregnancy
Expansion of maternal RBC mass, blood volume
RBC production in fetus
Iron- Dose
Determined by Hb & iron status prior (highly variable)
General pregnancy RDA=27 mg/day (vs. 15-18 mb/d non-pregnant)