Antenatal CareDR. Yasir KatibMBBS, FRCSCPerinatologist

Case I20 y old lady newly married for 4 months. Known case of DM since age of 2 years old. She is planning to get pregnant and visiting your clinic for pre-conceptional visit.What we should do?

PreconceptionPreconceptional visitMedical diseases controlMedications reviewDiet, smoking and illicit drugsImmunization SupplementationsConsultation

Prevention Folic acidReduces the risk of neural tube defects, (?required for normal cell division)400 micrograms/day for all women in the childbearing years 4 mg/day starting 3 months prior to conception and continue at least through the 1st trimester of pregnancy for high risk population

Case II20 y old lady newly married 4 months ago. Known case of DM presented with a delayed period and her LMP 5 weeks ago. She had a positive home pregnancy test and visit your clinic for antenatal careWhat we should do?

Antenatal care (ANC) goals and strategy

Explain the components and objectives of prenatal goalsDescribe the frequency and aim of each prenatal visitGenetic counseling and its available toolsRisks and benefits of the genetic tests

ANC ObjectivesTo ensure the birth of a healthy baby with minimal risk for the mother by Early, accurate estimation of GA Identification of the patient at risk for complications Ongoing evaluation of the health status of both mother and fetus Anticipation of problems and intervention, if possible, to prevent or minimize morbidity Patient education and communication

ANCPrenatal care is not a single intervention Quantity" Vs. Quality" of ANCA systematic review of observational studies and randomized trials concluded that there was no conclusive evidence that prenatal care improved birth outcomes Randomized trials have also shown that enhanced prenatal care did not result in improved outcomes compared to routine prenatal care

ANC ComponentsHISTORY PHYSICAL EXAMINATION LABORATORY TESTSDIAGNOSTIC IMIGING PATIENT EDUCATIONMEDICATIONS

HISTORYPersonal and demographic information Past obstetrical history Personal and family medical history Past surgical history Genetic history Menstrual and gynecological history Current pregnancy history Psychosocial information

Physical examination A complete physical examination SpeciallyUterine size and shape Evaluation of the adenexeaBaseline blood pressure, weight, and height

LABORATORY TESTS1st visit A standard panel of laboratory tests (Routine)CBCBlood gp & antibodies screenHbS AgRubella VDRLUrine C&SCervical PAP smear

LABORATORY TESTS1st visitIn high risk population Chlamydia swabHIVTFT

LABORATORY TESTSothers N. gonorrheaTBToxoplasmosis HCVBVOthers HB electrophoresis, cystic fibrosis, phenylalanine level etc

Follow-up visitsMajor goals (PET, malpresentation)Components Wt, B/P, SPH, FH auscultation, FM, presentationPatients concernsEducation

Follow-up visitsUncomplicated pregnanciesEvery 4 weeks until 28 wks Every 2 to 3 weeks from 28 to 36 wksWeekly until delivery

Follow-up visitsLaboratory follow-upGDM screening at 24-28 wksCBC & antibodies screenGBS screening (recto-vaginal swab)

DIAGNOSTIC IMIGINGUltrasoundMinimum requirementUsefulnessLimitationsOthersMRI

1st Trimester U/SConfirm pregnancyViabilityAssess GA (Dating)Multiple gestations (chorionicity / amnionicity)Maternal pelvic anomalies AIUM Standards and Guidelines

2nd Trimester U/SFetal normality: Head shape and size and internal structures (cavum pellucidum, cerebellum, ventricular size at atrium < 10 mm) Spine: longitudinal and transverse Abdominal shape and content at level of stomach Abdominal shape and content at level of kidneys and umbilicus Renal pelvis < 5 mm anteriorposterior measurement Longitudinal axis abdominalthoracic appearance (diaphragm and bladder) Thorax at level of a four-chamber cardiac view Arms: three bones and hand (not counting fingers) Legs: three bones and foot (not counting toes)

VALUE OF PRENATAL GENETIC DIAGNOSIS:Why do we do it?Reassurance Increases options Antenatal fetal treatment Preparation for outcome Avoidance of obstetric complications Selective termination

Prenatal Screening Modalities

Screening at 11-20 wks10 12 14 16 18 20 wksAllows adjustment of age-related risk Improved detection rateCourtesy Dr J Johnson and the Fetal Medicine Foundation

Non-invasive prenatal diagnostic testsMaternal Serum ScreenNuchal ScreenNuchal plus biochemistryUltrasound

Maternal Serum ScreenThree biochemical markersBHCGAFPEstriol

Gives age adjusted risk

Screens for Downs and NTD

MSS1/101/378Risk = age X OR BHCG X OR uE3 X OR AFP

MSS LimitationsSensitivity 70 %Specificity 95% ( False positive 5%)

Two reasons for a false positive:Wrong datesTwins

=Maternal age-based screening1/200 risk of miscarriageRationale =1/200 chance of abnormality30%70%

Assessment of Background RiskMaternal Age Trisomy 21 Trisomy 18 Trisomy 1347xxx/xxy/xyy45xTriploidyRisk %Courtesy Dr J Johnson and the Fetal Medicine Foundation

%Assessment of Background RiskGestational AgeSnijders et al 1999Courtesy Dr J Johnson and the Fetal Medicine Foundation

the skin is deficient in elasticity. . . . . . too large for the body Langdon DownObservations on an ethnic classification of idiots. Clinical Lecture Reports, London Hospital 1866;3:259.Nuchal TranslucencyCourtesy Dr J Johnson and the Fetal Medicine Foundation

Nuchal Translucency Gestation 11-14 wks CRL 45-84 mm Mid-sagittal view Image size >75% Neutral position Away from amnion Maximum lucency Callipers on-to-onCourtesy Dr J Johnson and the Fetal Medicine Foundation

Chromosome abnormalitiesBirth defects (cardiac, d.hernia)Genetic syndromesIncreased mortality (> 3.5 mm) Significance of increased Nuchal fluidCourtesy Dr J Johnson and the Fetal Medicine Foundation

FETAL CENTRE

Fetal Nuchal Translucency

Pathophysiology of increased nuchal translucencyAbnormal or delayed lymphatic development Venous congestion Cardiac failure Altered composition of extracellular matrix Failure of lymphatic drainage due to fetal hypokinesia Fetal anemia or hypoproteinemia Congenital infection Courtesy Dr J Johnson and the Fetal Medicine Foundation

Courtesy Dr J Johnson and the Fetal Medicine Foundation

FETAL CENTRE

Normal KaryotypeIUD / NND / Major anomaly

Increased NT at 10-14 wks (n=4,767)

Abnormal karyotype

3708 577 210 100 172

3583 470 141 50 62

Courtesy Dr J Johnson and the Fetal Medicine Foundation

FETAL CENTRE

Healthy Live Births

Increased NT at 10-14 wks (n=4,767)

First Trimester Biochemical MarkersPAPP-A: Pregnancy associated plasma protein AProduced by placental trophoblastIncreases in 10-14 week periodLower in DS pregnancies (0.43 MOM)Associated with 42 % DR at 5% FPR.Free - hCg: Free subunit of human chorionic gonadotrophin.Placental proteinDecreases in T1 like total hGCHigher in DS pregnancies (1.79 MOM)Associated with 23% DR at 5% FPRCourtesy Dr J Johnson and the Fetal Medicine Foundation

Fetal NT + Maternal age + hCG + PAPP-A at 11-14 wksInvasiveTesting 5%Screening at 11-14 wksCourtesy Dr J Johnson and the Fetal Medicine Foundation

INVASIVE TECHNIQUES FOR EARLY PRENATAL TESTINGChorionic Villus Sampling Amniocentesis

Amniocentesishttp://wchs.health.wa.gov.au/health/a/amnio.htm

Amniocentesis

AmniocentesisPerformed at or more 15 weeks Takes 2-3 weeks for KaryotypePregnancy loss risk 1/200Can get result of trisomies 13,18,21 and Turners Syndrome X0 in 48 hours with FISH (Florescent Insitu Hybridization)

Chorionic Villus Sampling

Chorionic Villus SamplingPerformed at 10-14 weeksTakes 2-3 weeks for the resultPregnancy loss rate 1/100Operator experience importantLink to limb abnormalities (still controversial)Placental mosaicism up to 3%, but little effect on outcome

Post TestA standard panel of laboratory tests (Routine) dose not includeRubella TFTVDRLUrine C&SCervical PAP smear

Post TestFirst trimester scan does not includeFetal morphologyViabilityAssess GA (Dating)Multiple gestations (chorionicity / amnionicity)Maternal pelvic anomalies

Post TestWhich of the following is not a cause for an abnormal MSSDowns syndromeIUFDTwinsWrong datesCongenital heart disease

Post TestA false positive on the MSS occurs in 1/20 tests

TrueFalse

Post TestList Two advantages of Amniocentesis over CVS

Decreased miscarriage rateLower risk of mosaicismNo association with limb reductions

Post testWhich of the following tests is the best at detecting Downs Syndrome

MSSNuchalNuchal plus PAPP A and Free BHCG

Post TestWhat is the miscarriage rate with amniocentesis?

0.5%3%5%10%

Post TestList one advantage of CVS over amniocentesis

Early results

*http://wchs.health.wa.gov.au/health/a/amnio.htm