Prenatal Assessment Flashcards
gestation
of weeks from last menstrual period
1st trimester
0-12 weeks
2nd trimester
13-24 weeks
3rd trimester
25-40 weeks
term pregnancy
37-42 weeks
Preterm
37 weeks
post-dates
after 42 weeks
gravida
total # of pregnancies regardless of whether they were carried to term
para
# of viable (>20 wks) births multiples count as 1 birth
nulligravida
never pregnant
nullipara
never delivered
primigravida
pregnant for the 1st time or has been pregnant 1 time
multigravida
pregnant more than one time
multipara
given birth 2 or more times
Reason for preconception counseling
ID pts at increased risk of complications before pregnancy
Age >35 at increased risk
Diet: folic acid, MVI; avoid EtOH, tobacco/drugs, caffeine, meds
Vaccinations: varicella, rubella, hep B
PMH: DM, mental health, STI, etc
Wt: under/over weight discussed
First 2 weeks of developing fetus
period of dividing zygote, implantation & bilaminar embryo
usually not susceptible to teratogens
prenatal death
Embryonic period 3-8 weeks
major morphological abnormalities
fetal period 9-40 weeks
physiological defects & minor morphological abnormalities
Urine pregnancy test
accurate 95-98% of the time sensitive w/in 7 days of implantation pregnancy detected before 1st missed period inexpensive use 1st morning void when possible
Serum hCG
gold std
qualitative results read as -/+
quantitative used for serial testing
level doubles q 48 hrs 1st 3-4 wks
leve peaks @ 60-70 days then level off
level should be 50-250 mlU/mL at the time of the first missed
period
progesterone levels
remain constant thru 1st 9-10 wks non viable pregnancies have lower levels highly predictive of preg outcomes performed if freq SAB if level <20, progesterone vaginal suppository Prometrium 100-200 mg
Risk factors for ectopic pregnancy
prior tubal preg tubal reversal surgery endometriosis IUD once IUP seen on sono, pt can be reassured
Sx’s of pregnancy
n/v heartburn breast tenderness back pain abdominal pain/cramping quickening vaginal d/c or bleeding skin changes urinary frequency ptyalism HA absence of menses nosebleeds, gums bleed constipation fatigue
ptyalism
excessive secretion of saliva
abdominal pain & cramping
assoc. w/ round ligament pain
MC problem associated with pregnancy
hyperemesis gravidum: freq. constant vomiting- dehydration, wt loss, electrolyte imbalance, poor appetite or food intake, ketonuria
Cervical & Vaginal tests on PE
pap
chlamydia
gonorrhea
as needed: BV, HSV, trichomonas
Pelvic exam
Hegar's sign Chadwicks sign cervical position & length uterine size via bimanual adnexal tenderness/enlarement fetal heart tones fetal mvnts after 18-20 weeks fetal position after 28 weeks
Hegar’s sign
softening of the cervix, about 4-6 weeks after conception
Chadwick’s sign
bluish discoloration of the cervix from vascular congestion, after 6th week of pregnancy
FHT (fetal heart tones)
120-160 bpm
heard at 10-12 weeks with Doppler
determining gestational age
+ signs
Fetal heart: fetoscope auscultation 17-20 weeks, ULS 5-8 wks
for cardiac activity
Mvnt: palpation of active fetal motion (quickening) at 18-20 wks
Visualization of fetus: ULS- fetal pole seen 5-6 wks
Dx of pregnancy
gestational sac appears at about 4 wks gestational age
grows at 1 mm a day thru the 9th week of pregnancy
gestational sac seen at the 4th-5th wk of gestation
serum hCG levels 1000-1500 mIU
gestational sac size
3-6 mm
dating the pregnancy
LMP- exact date? regular cycles?
Naegele’s rule: add 7 days, subtract 3 months from LMP for EDD
avg length of gestation ~280 days
confirm with ULS, best in 1st trimester
determination of gestational age using CRL
crown rump length (CRL) up to ~14 wks: +/- 5-7 days accuracy >16 wks, less accurate biparietal diameter (BPD) head circumference (HC) abdominal circumference (AC) femur length (FL)
Assessing fetal growth
10-12 wk: fundus at symphysis pubis
16 wk: fundus midway btw symphysis pubis & umbilicus
20-22 wk: fundus at umbilicus
measure from symphysis pubis to top of fundus
measure in cm: weeks gestation +/- 3 cm, most accurate btw 22-34 weks
topics of discussion: 1st visit
prenatal vitamins lab tests exercise nutrition sex outline of care handouts, books grooming, dental hygiene, travel
General health & nutrition counseling
drink plenty of water/fluids
get plenty of rest
exercise: avoid overheating/ maintain adequate hydration
contraindications
Nutrition: assess risk factors
encourage approp. wt gain 25-30 lbs pre-pregnant wt less than 90% or >135% adolescent less than 15 2+ more pregnancies during 2 yrs breast feeding multiple gestation food faddism, smoking, drugs, alcoholism therapeutic diet for chronic systemic dz
Diet
2000-3000 cal/day
veg may be deficient in essential AAs, iron, complex lipids
food allergies
Ca2+ intake 1000-15000 mg/day 4 servings (lactose intolerance?)
protein 5-6 gm/day above non-pregnant, 8 servings/day
breads & cereals 6 servings
fruits & veggies 3 servings
Folic Acid
800 mcg start preconception
prevention of neural tube defects
neural tube closes 18-26 days post conception
Iron
15 mg/day over RDA of 30 mg/day
Vitamin A
> 10,000 IU/ day is teratogenic
Vit C
vit C rich foods 3 servings
Common discomforts of pregnancy
n/v changes in libido
diarrhea angry/irritable
hemorrhoids constipation
heartburn loss of appetite
fatigue numbness of hands carpal tun
sciatica leg cramps
irregular heart beat abd. pain & cramping
schedule of future visits
once a month for 28-30 wks
every 2 wks until 36 wks
weekly until delivery
more frequent visits as indicated
evaluate at each visit
wt gain- eval fetal growth, nutritional intake BP: screen for PIH Fundal ht: eval fetal growth Leopold's maneuver: det. fetal position Fetal heart tones: eval fetal well being edema: screen for PIH UA: glucose & protein sx's: ID problems, discomforts
prenatal revisit questions
HA exposure to dz
visual changes skin rashes/itching
swelling signs of labor
pain in chest, legs, abd, back accidents/falls
problems w/ urination changes in fetal motion
vaginal bleeding/abnl d/c vaginal lesions/sores
vaginal bleeding
miscarriage
SAD
ectopic
fluid leaking from vagina
PROM (premature rupture of membranes)
persistent HA, dizziness, edema, RUQ pain
PIH (pregnancy induced hypertension)
decreased fetal mvnt
fetal compromise
fever, chills
infection
recurrent vomiting
hyperemis gravidum
std OB panel
blood type, Rh & antibody screen Hgb & Hct pap smear & chlamydia screening rubella immunity, Hept B sAG urine cx RPR, HIV thyroid function
What causes less severe hemolytic anemia, jaundice in newborns
ABO incompatibility occurs in 1st pregnancies
majority occurs in Type O mothers carrying type A or B fetus
Rhesus (Rh) factor
an inherited antigen on RBC surface
Dd, Cc, Ee are antigens
Rh-D presence is Rh +
Rh-D absence is Rh-
Rh negative pregnant women
pt produces IgG antibodies in response to Rh+ fetal RBC in maternal circulation- sensitization thru previous pregnancy, transfusion, trauma causing maternal/fetal blood to mix
IgG crosses placenta
coated erythrocytes destroyed in reticuloendothelial system causing fetal hemolytic anemia, hydrops & fetal death
fetal hydrops
accumulation of fluid or edema in at least 2 fetal compartments
At risk mothers should also be screened for
gonorrhea TB toxoplasmosis Hep C Ab varicella immunity BV, Trichomonas, HSV Chagas dz lead level
testing for genetic d/o
advanced maternal age >34 yo thalassemia (Asian, Mediterranean background) Hemoglobinopathies (African Americans) Tay-sachs (Ashkenazi Jews) cystic fibrosis (carriers) Serum phenylalanine level (PKU) fragile X (developmental delay)
1st & 2nd trimester screening
all women should be offered screening for Down syndrome & other genetic abnormalities, especially those at higher risk
integrated screening w/ blood tests & nuchal translucency (ULS)
CVS sampling
Amniocentesis
ULS
Integrated screening
Screening test, NOT diagnostic
Nuchal translucency @ 11-14 wks
maternal serum PAPP-A (preg. assoc. plasma protein A) & beta
hCG at 11-14 weeks
maternal serum E3 (unconjugated estriol), AFP, beta hCG at 15-
16 wks
detection of ~90-95% of Trisomy 21
Nuchal Translucency
use ULS to measure amt of fluid accumulation behind baby’s neck
non-invasive test
ID increased risk for Down syndrome
offered to women ages 11-14 wks
90% of fetuses with NT of 3 mm at 12 wks gestation are nl at birth
10% have major abnormalities
blood work at 11-14 wks
performed on mother’s blood at 10w 3d to 13w 6d
measures the levels of a protein found in the blood of all pregnant women, PAPP-A (pregnancy associated plasma protein-A)
also measure quantitative serum beta-hCG
blood work at 15-18 wks
AFP
beta-hCG
E3
Inhibin A
Integrated screen summary
will detect up to 92% of babies affected w/ Down Syndrome & up to 90% w/ Trisomy 18
will also detect up to 80% of babies that have open neural tube defects such as Spina Bifida
1st & 2nd trimester results are combined, so risk assessment available when 2nd trimester blood work is completed
Indications for Amniocentesis
assessment of: presence of bilirubin L/S ratio genetic d/o's fetal sex chromosomes advanced maternal age \+ AFP or 1st trimester screen X-linked dz (hemophilia) carriers of autosomal recessive d/o's
Amniocentesis
under ULS guidance, small amt of amniotic fluid removed thru the abdomen- 20 cc anmiotic fluid- cultured- kayotyped
detects most chromosomal d/o’s w/ high degree of accuracy: Down syndrome, Tay-Sachs, Neural tube defects, spina bifida, etc
risk of miscarriage as a result of amniocentesis 1 in 400 or less
indications for chorionic villus sampling
> 35 yo
previous infant w/ chromosome abnormality
mother carrier for x-linked dz
parents known carriers of autosomal recessive inherited d/o’s (Tay-sachs, CF, inborn errors of metabolism)
CI of chorionic villus sampling
IUD
bleeding
cervical stenosis
PID, HSV, GC
Chorionic Villus Sampling
10-12 wks gestation
provides earlier detection of DS, CF, TS, SCD
Procedure: removal of tiny piece of tissue from the placenta
needle inserted thru abdomen/catheter thru cervix w/ ULS
visualization
cultured for karyotype analysis
Advantages/Disadvantages of CVS over Amniocntesis
Advantage: performed earlier in preg- 10-12 wks rather than 15-20 wks. Results are avail. by end of 3rd month
Disadvantage: spinal cord defects cannot be detected. ULS performed later in pregnancy to screen for spinal cord defects
3rd Trimester Testing
26-28 wks: GDM screening, Rhogam if Rh-
35-37 wks: vaginal rectal swab for GBS
Milestone Visits
6-12 wks: confirm preg, discuss CVS, initial labs, complete Hx, PE
10-12 wks: determine fetal age by ULS; CVS
11-14 wks: 1st trimester screen
15-20 wks: quad screen, ULS, Amnio if high risk
24-28 wks: GTT for GDM, Ab screen if Rh-, Hgb/Hct
35-37 wks: GBS screen
