Prenatal Care Flashcards
Gestational Age (GA)
age in days/weeks from the last menstrual period
Embryo
from time of fertilization to 8 weeks (GA 10 weeks)
Fetus
after 8 weeks to time of birth
Infant
time between delivery and 1 year old
First trimester
1st 14 weeks
Second Trimester
14-28 weeks
Third Trimester
28 weeks until after delivery
Previable
infant delivered before 24weeks
Preterm
24-37 weeks
Term
37-42 weeks
Post term
past 42 weeks
Gravidity
number of times woman has been pregnant
Parity
number of pregnancies led to birth after 20 weeks (or >500g infant
Term, Preterm, Abortions, Living Children
Goals of Prenatal Care
- accurate estimate of gestational age
- deliver healthy, term infant without impairing maternal health
- identify and treat high risk patients
- patient education
Maternal Physiology: Cardiology
Output increases
stroke volume increases
pulse increases (15-20BPM)
systolic ejection murmur and S3 gallop common
PVR falls
Fall in BP in 2nd trimester, return to normal in 3rd trimester
Maternal Physiology: Respiratory System
- Unchanged: RR, VC, Inspiratory reserve volume
- Decreased: functional residual capacity, expiratory reserve volume, residual volume, TLC
- Increased: IC, TV
Maternal Physiology:
Renal System
- increased kidney size and weight, ureteral dilation, bladder becomes intra-abdominal organ
- GFR increases 50%
- CrCL increases 150-200cc/min
- BUN and serum Cr decrease by 25%
- increase in tubular reabsorption of sodium
- marked increase in renin and angiotensin but reduced vascular sensitivity to their hypertensive effects
- increased glucose excretion
Maternal Physiology:
Hematologic System
- plasma volume increase 50%
- RBC volume increase 30%
- WBC count increases
- platelet count decreases ( But still WNL!)
- increases fibrinogen, factors 7-10 (hypercoaguable state)
- placenta produces plasminogen activator inhibitor
Maternal Physiology: GI system
decreased motility (due to progesterone) reduced gastric acid secretion
Maternal Physiology: Uterus
weight increases (70-110g) blood flow increases to about 750cc/min or 10-15% of CO (significant: risk during c-section)
Maternal Physiology: Cervix
increased water content and vascularity
increases cervical mucous secretions
Diagnosis of Pregnancy
Confirm –>HCG (urine as sensitive as serum)
-can be positive 1wk after fertilization
Viable pregnancy
- TVUS shows gestational sac as early as 5wks or 1500-2000HcG
- shows fetal HR as early as 6wks or 5000-6000HcG
First questions to ask pregnant female
Was it planned?
Are you planning to continue this pregnancy?
History of Prenatal Patient
Menstrual Cycle
Previous pregnancies–>complications
Dating
PMH: HTN, DM, asthma, depression, bladder or kidney infections, bleeding/clotting disorders, anesthesia problems
PSH: C-sections, cervical procedures, abdomino-pelvic surgeries
Allergies
Genetic Hx
High Risk for Pre eclampsia
High BP (chronic or in prior pregnancy) DM1 or 2 Twins/triplets Renal disease Autoimmune disease
Moderate Risk for Pre eclampsia
1st baby BMI>30 mother/sister with it AA receive public health insurance (low ses) 35 or older Hx of LBW previous miscarriage/complicated pregnancy >10yrs since last pregnancy
Prevention of Pre eclampsia
81mg daily ASA orally from 12 weeks until delivery if:
- any high risk factor
- 2 or more moderate RFs
Important Questions to ask Prenatal Patient
Financial concerns
Domestic Violence
-homicide leading cause of pregnancy-associated death in 90s
-RFs: age <20, AA, late/no prenatal care
Other Stressors
-access to healthcare
-unplanned pregnancy
-substance abuse (5 Ps Screening Tool!!!)
Chadwick’s sign
bluish discoloration of vagina and cervix
Hegar’s sign
softening of uterine consistency and ability to palpate/compress the connection between the cervix and funds
Goodell’s sign
softening and cyanosis of the cervix at or after 4 wks
Ladin’s sign
softening of uterus after 6 weeks
Other pregnancy signs
Breast swelling/tenderness
Linea nigra
Telangiectasias
Palmar erythema
Pregnancy Sx
Amenorrhea N/V Breast pain Fatigue Quickening (fetal movement)
Initial PE
Vitals Thyroid Heart Lungs Breast (teach BSE/discuss BF) Abdomen Pelvic (pap, GC/CT, bimanual) Extremities: edema Influenze Vax \+/-US
Nagele’s Rule
Dating Pregnancy
Calculate EDC by subtracting 3 mos from LMP + 7 days
Uncertain LMP–>US to determine EDC
- most accurate in 1st trimester
- measure by crown-rump length in the 1st half of 1st trimester (usually accurate to within 3-5 days)
1st Trimester Labs
CBC Blood type and screen RPR/VDRL Rubella antibody screen Hep B surface antigen VZV titer HIV Gonorrhea and Chlamydia cultures Pap smear Urinalysis and Culture \+/-PPD GTT if BMI>30 \+/- CF, Taysachs, SMA, other genetic tests
CBC
Initial labs and 28wks Slightly evaluated WBC normal Dilutional anemia normal -start iron and colace when Hct <32% Consider Thalassemia if MCV is low Thrombocytopenia can be normal -caution <100!
Type and Screen
- if Rh negative –>patient will need Rhogam at 28wks or anytime she has vaginal/uterine bleeding
- Ab screen positive: consult perinatologist
- ->Rh antibodies can destroy fetal RBCs causing hemolytic anemia (can be fatal to fetus)
GDM Screening in 1st Trimester
- BMI>30
- prior pregnancy with GDM or previous infant >4000g (9lbs)
- high risk ethnicity: AA, latino, Native American, asian American, Pacific Islander)
- HgbA1c>5.7% or hx of known impaired glucose metabolism (PCOS, DM)
- physical inactivity
- 1st degree relative with DM
- HTN
- Hx of CVD: HDL <35mg/dL or Triglyceride >250mg/dL
GDM Screening Results
- Pass 1st trimester–>repeat at 24-28weks
- Fail 1st trimester, 3hr GTT is done
- passes 3hr GTT–>repeat GTT at 26-28 weeks
- Fails 3hr GTT–>dx of GDM
- 1st trimester DS>200, dx of GDM
GDM Screening (all patients)
24-28wks
GLT: glucose loading test
GTT: glucose tolerance test –>DIAGNSOTIC
GLT : Glucose Loading Test
50g oral glucose loading dose and check serum glucose 1 hr later
> 130mg/dL–>do GTT
GTT: Glucose Tolerence Test
DIAGNOSTIC
- fasting serum glucose
- 100g oral glucose loading dose
- serum glucose at 1, 2, 3 hrs after oral dose
- elevation of 2/more values=GDM
RPR/VDRL
rapid plasma regain/venereal dz research lab –> SYPHILLIS
*pregnancy is a risk for false positive
- if reactive –>check FTA-ABS
- fluorescent treponemal antibody-absorption
- consult perinatologist
- 50% untreated syphillis leads to infected baby
- risks: miscarriage, stillbirth, neonatal death, baby with severe neurological problems
Rubella
administer vaccine post partum if non-immune
HBsAg : Hep B surface antigen
detects 1-12 weeks post exposure
- HBsAb=recovery and immunity
- HBeAg= acute infection
- diagnosed with IgM HBcAB
chronic infection diagnosed by IgG HBcAB (no IgM)
*if pt. infected–>notify Peds
Gonorrhea and Chlamydia
DNA probe, swab mucus and insert into os
- if positive-
- treat patient and partner, -promote abstinence during treatment
- test of cure 4wks after tx
CF Carrier Screening
- offer at pre conceptual or new OB visit
- increased change of carrying if close relative affected or being white
- tests for 33 mutations on chromosome 7
Tay Sachs
- mutations in HEXA gene
- AR inheritance
- accumulation of gangliosides in CNS causes early childhood death
- carrier testing should be offered when at least 1 parent is
- Ashkenazi Jewish (1/30 carrier frequency)
- Pennsylvania Dutch
- Southern Louisiana Cajun
- Easter Quebec French Canadian Descent
Spinal Muscular Atrophy
- progressive muscle weakness and paralysis
- 1 in 50 regardless of ethnicity are carriers of gene
- both parents carries –>1 in 4 chance
Screening for Fetal Chromosomal Abnormalities
should be offered to all women before 20 weeks regardless of maternal age
type of screening is patient dependent (risks/desires)
Maternal Serum Screening
offered to all, most important for AMA
MS-AFP, First screen and NIPT testing
Sequential Screening
1a: Blood test for serum levels of PAPP-A and free B-hCG (11-13wks)
1b: US for nuchal translucency (11-13wks)
Part II: blood test for serum levels of MS-AFP, estriol, B-hCG, and inhibit (15-18wks)
- part I detects 70% DS, 80% trisomy 18
- part II detects 95% DS, 90% t18 and 80% NTD
- detection of DS in twins (dizygotic) 80% and monozygotic 93% (no T18)
- not recommended for triplet +, fetal anomaly or reduction of fetus
Alternatives for patients late to prenatal care (fetal chromosomal anomaly screening)
- MSAFP (16-18wks)
- elevated: increased risk of NT defects
- decreased: DS/aneuploidies
*NIPT
- US (18-20weks)
- fetal survey, amniotic fluid volume, placental location and gestational age
Quad Screen
- MSAFOP, HCG, estriol, inhibin A
- detects Trisomy 21, 18, and NTD
- between 15-18wks (up to 20)
- cannot be used for multiple gestations, screening test only
- positive:
- refer to genetic counseling
- high resolution US
- +/-amniocentesis
Advanced Maternal Age (AMA)
women 35 or older at time of delivery
offer maternal serum screening
offer NIPT
offer genetic counseling with possible diagnostic test
-CVS or amniocentesis
NIPT Recommendations
- AMA (>35)
- Fetal US findings indicating increased risk of aneuploidy
- HX of prior pregnancy with trisomy
- test result for aneuploidy (1st trimester, sequential or quad screen)
- parental balanced robertsonian translocation with increased risk of fetal trisomy 13 or 21
NIPT: Non-invasive Parenteral Testing
*cell-free fetal DNA (cfDNA) testing for fetal trisomies (21, 18, 13) in maternal blood
- 99% detection for DS
- 98% for trisomy 18
- 70-90% Trisomy 13
- detection of abnormal # of sex chromosomes 99%
NIPT additional considerations
- no in twins (including vanishing twins)
- should not substitute other diagnostic testing
- indeterminate result?
- genetic counseling
- detailed US
- other diagnostic testing
- risk with obesity >200lbs
Ultrasound
- at initial visit to measure CRL if uncertain LMP
- 1st trimester bleeding
- anatomy survey b/t 18-20wks
- any time fundal height is >3cm discrepant from Ga
- confirm presentation at or after 37 wks
Amniocentesis
- 15-20wks to obtain fetal karyotype
- procedure related loss 1 in 300-500
- complications: transient vaginal spotting, amniotic fluid leakage, preterm labor, chorioamnionitis, and rarely needle injury to fetus
- <15wks not recommended (high risk)
Chorionic Villus Sampling
- obtains fetal karyotype 10-13wks (99%)
- catheter placed intrauterine cavity, sm amount of chorionic villi aspirated from placenta
- fetal loss rate same (ish) as amniocentesis
Cordocentesis
- percutaneous umbilical blood sampling (PUBS): puncture umbilical vein under direct US guidance
- karyotype analysis of fetal blood w/in 24-48hrs
- pregnancy loss rate <2%
- rarely needed, may be useful to evaluate chromosomal mosaicism discovered after CVS or amniocentesis is performed
3rd Trimester Diagnostics
*27-29wks
CBC
GLT
RPR/VDRL
- if high risk–>repeat GC and CT, also HSV screening
- CXR if PPD+
- group B strep (36 wks)
Group B Streptococcus
screen all patients at 36wks
culture lower vagina and anus (must go through sphincter)
PCN allergy, ask for sensitivities
Routine Prenatal Vistis
- BP
- weight
- urine dipstick (protein and glucose)
- fundal height, weight and fetal position
- auscultation of fetal heart tones
Frequency of visits
less than 28wks: every 4wks
28-36: every 2 wks
> 36: every week
1s trimester questions
cramping or bleeding?
N/V?
2nd trimester questions
Cramping/bleeding?
fetal movement?
3rd trimester questions
contractions, leaking of fluid, bleeding?
fetal movement?
Routine Problems
- N/V
- LBP
- constipation
- contractions
- dehydration
- edema
- GERD
- hemorrhoids
- PICA
- round ligament pain
- urinary frequency
- varicose veins
- carpal tunnel syndrome
Prenatal Supplements
- 800mcg folic acid
- most effective when given 2 mos prior and during 1st months
- green leafy veggies, oranges cantaloupe, bananas, milk, grains and organ meat
*avoid excessive fat soluble vitamins (D, A, K, E)
prenatal nutrition : what to avoid and limit
caffeine : 500mg/day
Fish: mercury risk
-avoid shark, swordfish, king mackerel and tilefish
-limit shellfish and sm. ocean fish to 12oz/wk
-limit other fish to 6oz/wk
-limit canned tuna to 6 oz/wk
prenatal nutrition: calories
- calories: increase 15%kcal/day (2200 cal)
- protein: add 10-30g/day (75g total)
- Iron: supplement 30-60mg/day
- Ca: 1200mg/day
Nutritional Referral (WIC referral maybe)
- inadequate weight Gian
- PICA
- eating disorder
weight gain
avg: 25-35 pounds
15 lbs if obese
40lbs if underweight
exercise
- continue at usual level
- HR goal: 70% of 220-age (140)
- limit new exercise
- avoid over heating
- avoid supine
- avoid scuba, skiing, contact sports after 1st trimester
2nd trimester counseling
- birthing classes
- preterm labor risks after viability
- breastfeeding
- rhogam at 28wks if negative
3rd trimester counseling
- analgesia/anesthesia in labor
- operative vaginal delivery or C section
- travel
- fetal kick counts
- L&D tour
- pediatricion
- GBS
- HSV
- what to Bring to hospital
- circumcision
genital HSV in pregnancy
- IgG Toc
- HSV-1 positive- could be oral or genital infection
- IgM not helpful
Most women with newborn who acquires neonatal herpes DO NOT have a history of clinically evident herpes
Prevention of Neonatal herpes
- prevent acquisition of genital HSV during late trimester
- avoid exposure of neonate to herpetic lesion and viral shedding during delivery
- avoid vaginal intercourse if partner is + (during 3rd trimester)
- verbally screen for genital herpes
- examine all women for sx
- C-section if sx present (risk not fully elminated)
- suppressive therapy in women at 36wks if recurrent genital herpes
- Valacyclovir 500mg BID or Acyclovir - BF not C/I unless lesion on breast
- universal precautions with active oral HSV
Vaccines recommended ALL
Flu during flu season
Tdap 27-36wks
Vaccines safe if indicated
pneumococcal, hep A or B, rabies, polio typhoid
Vaccines C/I
MMR, varicella, live virus vaccines
Post partum contraception
- discuss 3rd trimester
- consent required tubal ligation
- importance of inter-pregnancy interval (esp. w/ C-section)
prior C -section?
- document uterine scar
- discuss risk/benefits of VBAC vs. repeat C-section
- have pt sign consent
- schedule c-section (39wks )
Fetal movement assessment
Indication
-maternal perception of decreased/absent fetal movement
Technique: mother counts kicks during specific time
-have mom eat/drink something then lay still
Non stress test
- measurement of fetal HR with movement
- Reactive (normal)= 2/more fetal HR accelerations within 20mins
- Nonreactive=insufficient fetal HR accelerations over 40mins
- acidotic, neurologically depressed
Contraction Stress Test
looking for presence/absence of late Fetal HR decelerations in response to uterine contractions
Late decels= decals that reach nadir after the peak of contractions and usually persist beyond the end of the contraction
Variable decels= cord compression
-think oligohydramnios
Biophysical Profile
*NST, fetal breathing movements, fetal movement, fetal tone, AFI
each component =2 or 0
normal: 8 or 10
equivocal: 6
abnormal: 4 or less
*oligohydramnios–>warrants further evaluation regardless fo score
Amniotic Fluid Index (AFI)
summation of the largest cord-free vertical pockets of the 4 quadrants of an equally divided uterus
Oligohydramnios
no US measured pocket of fluid >2cm or AFI of 5cm or less
- BAD: anomalies or placental dysfunction
- requires close maternal/fetal surveillance or delivery
Polyhydramnios
AFI >24cm (or equal)
can be normal, cause Prom or malpresentation
Post partum Visits
Vaginal Delivery: 6wks
C-section: 2 (incision check) and 6 weeks
Consider sooner/follow-up if complications (3/4th degree tear, HTN)
