Pgo - 31 Prenatal Care And Screening

Front 1

Initial screening labs

Back 1

ABO & Ab screen,
Hgb/Hct- blood cell count,
PAP smear,
RPR - rapid plasma reagin - test for syphilis
GC/Chlamydia,
urine screen,
Hep B,
HIV,
colposcopy

Front 2

When is 1st trimester screening performed?

Back 2

Between 11 and 14 weeks
Combined screen: blood test + ultrasound

Front 3

Triple test
Quad test

Back 3

MSAFP, uE3, hCG or B-hCG
MSAFP, uE3, hCG or B-hCG and Inhibin - A

Front 4

24-28th week screening

Back 4

Glucose tolerance test

Front 5

Weeks 36-40 screening

Back 5

Non-stress testing.
Fetal HR should increase by 15 bpm two times over the course of 20 min. ECG

Stress testing give small dose of oxytocin and reaction of fetoplacental unit.

Front 6

Routine prenatal care - done on every screening

Back 6

Record swelling ?
weight
urinalysis
bimanual vaginal exam
after 24 week detection of viability

Front 7

Goal of prenatal care is

Back 7

to select gravidas at risk for development of major complications and early prevention/intervention in order to affect improved outcome

Front 8

Developmental gestational age markers (approx)
Fetal heart auscultation
Quickening
Fundal height measurements

Back 8

10-11 weeks ( heart formed by 5th week)
16-20 weeks ( mother feels fetus movements)
20 weeks - at umbilicus, after that every cm from pubic symphisis and up to fundus of uterus = 1 week

Front 9

Best way to determine gestational age

Back 9

Menstrual age (calendar gestational age) =
gestational age is often defined as the time elapsed since 14 days prior to fertilization. This is approximately the duration since the woman's last menstrual period (LMP)

Front 10

Ultrasound dating Early pregnancy -

Back 10

Crown Rump Length (CRL): CRL + 6.5 approximates gestational age (+7 days)

Ie if CRL 1.2 cm gestational age in weeks is 7.7 weeks

Front 11

Ultrasound dating Mid pregnancy (12-28 weeks) -

Back 11

correlation between ultrasound and menstrual dating is +10-14 days

Front 12

Ultrasound dating in late pregnancy

Back 12

ultrasound accuracy as single estimate of gestational age is not great (+21 days)

Front 13

Circumstances that may alter measurement reliability of ultrasound

Back 13

• Multiple gestation
• Oligohydramnios/Polyhydramnios
• Uterine pathology

Front 14

Fetal movements:
indicates what
when in pregnancy is fetal movement greatest

Back 14

greater movement better wellbeing of fetus
force of fetal movement greatest in early pregnancy

Front 15

What is H/H - how is it changed in pregnancy
When is it lowest in pregnancy

Back 15

Hemoglobin / hematocrit - both Hb and plasma increase but plasma increases more.
Lowest by week 28

Front 16

Anemia can be a screen for:

Non-invasive screen for anemia in fetus

Back 16

o Maternal disease
o Hemoglobinopathy
o Anemia (Iron deficiency; Folate; B12)

Fetal middle cerebral artery peak systolic velocity (Doppler)

Front 17

Urinalysis for what and what may it signify

Back 17

Proteinurea - renal disease, preeclampsia, infection
glucose - not reliable association with serum glucose
Cystitis and Pyelonephritis much more common in pregnancy - use low threshold for diagnosis

Front 18

Laboratory tests – prenatal care

Back 18

• Hemoglobin/Hematocrit
• Urinalysis/Urine Culture/Urine Dipstick
• Glucose testing
• Blood Type/Rh
• Serologic test for Syphilis
• N. Gonorrhea/Chlamydia
• Other tests

Front 19

Visit interval – pregnancy (uncomplicated patient)

Back 19

• Conception until 36 weeks gestational age - Every 4 weeks
• 36-40 weeks gestation - Every week
• High risk pregnancy may alter visit intervals
• Preterm labor risk may alter pelvic exam interval
• Post dates pregnancy - (Nonstress testing) - Twice a week

Front 20

Down syndrome (trisomy 21) risk factor and lab

Back 20

• 1/800 Live births
• Risk increases with advancing maternal age
• Lab findings
o Elevated hCG + INH-A (inhibin alpha → regulate gonadal stromal cell proliferation negatively)
o Lower than average levels of MSAFP and unconjugated estriol

Front 21

Edward’s syndrome (trisomy 18) - inc and lab

Back 21

• 1/5000 live births
• High rate of fetal and neonatal death
• Lab findings:
o Lower than average levels of all three markers

Front 22

Open neural defect - incidence and lab results

Back 22

• 7-15/10,000 live births
• Adequate folic acid reduces incidence
• Lab findings:
o Elevated MSAFP

Front 23

What has evolved in the first trimester (11-14 weeks)?

Back 23

• Nuchal Translucency (NT) - Downs
• Serum biochemistry
• Nasal Bone (NB) - Downs

• Tricuspid regurgitation (TR)
• Frontomaxillary facial angle (FMF Angle)

Front 24

Symptoms to evaluate during pregnancy

Back 24

• Bleeding
• Decreased fetal movement
• Swelling
• Headache
• Visual disturbance
• Contractions
• Leakage of fluid

Front 25

Swelling (edema) and preeclampsia
Weight gain and warning signs

Back 25

o >4 lb weight gain in one week
o Sudden swelling of hands or face
o Presence of other symptoms associated with preeclampsia

Front 26

Headache/Visual Disturbance
• Headache and visual disturbance (double vision, photophobia, etc.) may be:

Back 26

• Headache/visual disturbance with hypertension should be considered preeclampsia until proven otherwise

Front 27

o Warning signs for vaginal discharges during pregnancy. Color and associated pathology

Back 27

o Watery discharge = possible ROM
o Green discharge = possible meconium (=the dark green substance forming the first faeces of a newborn infant)
o Itching discharge = possible vaginitis
o Bloody discharge = cervicitis or serious causes of vaginal bleeding

Front 28

Tests to determine if membranes are ruptured

Back 28

o Temesvary exam - bromthymol – changes colour to blue-green due to alkaline fluid
o pH: Amniotic fluid typically with alkaline pH (>7.0)
o Pooling or direct leakage: Fluid will directly leak out of cervix during Valsalva

Front 29

Consequences of rupture of membranes

Back 29

• Prolonged rupture of amniotic membranes (>24 hours) associated with increase in intrauterine infection
• Preterm ROM associated with spontaneous labor in over 90% of patients

Front 30

Contractions in pregnancy

Back 30

• Uterine contractions occur throughout pregnancy (4/hour in early third trimester)
• Frequency of contractions increases just prior to the onset of perceived labor
• Persistent contractions of closer than 15 minutes apart that do not resolve with simple bedrest or fluids need some sort of evaluation
• Cystitis, multiple pregnancy and polyhydramnios also associated with uterine irritability

Front 31

Weight gain in pregnancy
Normal total sum
Per week
Excessive

Back 31

7kg - 10kg with fat reserve for milk prod
200-500g
Excessive weight gain over 20-25 kg may increase risk of gestational diabetes and other complications

Front 32

Bloop pressure in pregnancy

Back 32

• Blood pressure normally decreases to a nadir at midpregnancy
• Blood pressure then rises to early pregnancy levels by term

Front 33

Pregnancy: risk for abnormal outcome

Back 33

• Major congenital abnormality 1/50
• Single gene disorder 1/100
• Major chromosome disorder 1/200
• SAB in 1st trimester 1/8
• Stillborn (in North America) 1/125
• Perinatal death 1/150

Front 34

Prenatal diagnosis techniques

Back 34

• Chorionic villus sampling (CVS)
• Amniocentesis
• Percutaneous umbilical cord blood sampling (PUBS)
• Fetoscopy – fetal tissue biopsy
• Ultrasound
• Pre-implantation diagnosis
• Fetal cell sorting in maternal blood

Front 35

Indications for prenatal diagnosis

Back 35

• Maternal age ≥ 35
• Previous child with chromosome abnormalities
• Parent with chromosome abnormality
• Family history of chromosome abnormality
• X-linked disorders
• Metabolic disorders
• Neural tube defect risk
• Positive prenatal screening test
• Fetal anomaly suspected/diagnosed on ultrasound

Front 36

Early amniocentesis -
when ?
why is it more difficult ?
how much fluid is withdrawn?

Back 36

between 11 and 14 weeks
membranes not yet fused to uterine wall
1ml for each weak of gestation

Front 37

Second trimester amniocentesis
when?
how much fluid? what to do with first 1-2 ml?
fetal loss % ?

Back 37

15 - 20 weeks
20ml, first 1-2 ml discarded or used for AFP testing
0,5% fetal loss

Front 38

Chorionic villi sampling
when?
route?
benefit?
fetal loss %

Back 38

10-13 weeks
transcervically or transabdominally
allows earlier testing and results
1% fetal loss

Front 39

PCUB - percutaneous umbilical cord sampling
aka?
primary indications?
benefit?
placement of placenta and complications
death rate?

Back 39

- cordocentesis / fetal blood sampling
- assess / treat confirmed red cell or platelet alloimmunization, evaluation of non-immune hydrops
- Rapid diagnosis - 24-48 hrs karyotyping
- anterior placenta increased risk of hemorrhage
- 1,4 %

Front 40

Fetal tissue biopsy
muscle biopsy?
skin biopsy?

Back 40

muscular dystrophy and mitochondrial myopathy
epidermolysis bullosa

Front 41

Thyrotoxicosis and the fetus

Back 41

IgG stimulating antibodies from Graves affected mother cross placenta and cause thyrotoxicosis.

Cordocentesis and check for thyroid hormones.
Propylthiouracil to suppress thyroid if hyperthyroidism of fetus confirmed