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Fetal growth and well-being. DATING SCAN. SAC FROM 5WKS FETAL POLE 6WKS FETAL HEART 7 WKS LIMB BUDS 8 WKS HEAD 12WKS NT 11 TO 14 WKS FULL ANOMALY 18-20 WKS. CROWN RUMP LENGTH. BPD HC FAC FEMUR LENGTH. ANOMALIES – ULTRASOUND 18 TO 20 WEEKS. Spina Bifida Anencephaly
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DATING SCAN SAC FROM 5WKS FETAL POLE 6WKS FETAL HEART 7 WKS LIMB BUDS 8 WKS HEAD 12WKS NT 11 TO 14 WKS FULL ANOMALY 18-20 WKS CROWN RUMP LENGTH BPD HC FAC FEMUR LENGTH
ANOMALIES – ULTRASOUND 18 TO 20 WEEKS Spina Bifida Anencephaly Cardiac Renal Diaphragmatic hernia limbs Facial Chromosomal aFP Late > 20/40 Renal Microcephaly Hydrocephalus Ureteral valves
ULTRASOUND GUIDANCE AMNIOCENTESIS, L/S RATIO CVS CORDOCENTESIS, TRANSFUSION PARACENTESIS SHUNTS bladder, ascites kidney, head LIVER BIOPSY, SKIN FETAL REDUCTION
OTHER OBSTET Estimated fetal weight Twins discordance Behavioural states ( B.P.S. ) Presentation Placenta ( previa, RPC’S)
DEFINITION OF I.U.G.R Less than 2500 grams SGA vs AGA Less than 5 centile for GA Approx. 4 - 7 % of all infants are IUGR
Appropriate screening tests in an early, uncomplicated pregnancy include all of the following except: a) repeat human chorionic gonadotropin b) hemoglobin c) syphillis serology d) cervical cytology e) blood type and Rh factor
CAUSES OF I.U.G.R MATERNAL FACTORS • Malnutrition • Drugs • Substance Abuse • Diseases • Infections
CAUSES OF I.U.G.R FETAL CAUSES - Chromosomal Abnor mality - Congenital Abnor mality - Multiple Gestation - Congenital Infection
CAUSES OF I.U.G.R PLACENTAL FACTORS Placental Perfusion Placental Abnormalities - Abnormal Cord Insertion - Abruption - Circumvallate placentation - Placental Memangioma - Placental Infection - Twin to Twin Transfusion
CAUSES OF FETAL OVERGROWTH Maternal Diabetes Maternal Obesity Excessive Maternal Weight Gain
IMMEDIATE NEONATAL MORBIDITY IN IUGR Birth asphyxia Meconium aspiration Hypoglycemia Hypocalcemia Hypothermia Polycythemia, hyperviscosity Thrombocytopenia Pulmonary hemorrhage Malformations Sepsis
ULTRASOUND CLINICAL TESTS Growth parameters Fetal weight Amniotic fluid volume Biophysical profile score Fundal height Maternal weight Fetal Kicks BIOCHEMICAL TESTS aFP HPL oestriol crf DOPPLER CARDIOTOCOGRAPHY Stress tests Non stress tests
FUNDAL HEIGHT S - F HEIGHT IN cms + 2 = no of weeks Sensitivity 60 % Use of S - F charts MATERNAL WEIGHT wks gain 0 - 20 4 kg 21 - 28 4 kg 29 - 40 4 kg Average 12 kg Not very reliable guide Big mother
BIOPHYSICAL PROFILE CTG 0 - 2 MOVEMENT TONE LIQUOR VOLUME BREATHING MAX. 10 DOPPLER What is it? Uteroplacental waveforms Umbilical artery Carotid artery Descending aorta
FETAL ACTIVITY Cardiff “count to ten “ chart towards term 10 movements in 12 hours Randomized study
CARDIOTOCOGRAPHY Maybe as good as BPP movement Non - stress uterine activity Syntocinon infusion Stress tests nipple stimulation Features of the normal CTG rate 120 - 160 BTB variation 5 - 15 Accelerations present No decelerations
The perinatal mortality rate is defined as : a) the number of neonatal deaths that occur per 1000 live births b) the number of still births that occur per 1000 births c) the number of fetal deaths within the first week after birth d) the number of still births and neonatal deaths per 1000 live births
WHY FETAL ASSESSMENT ? 1. To prevent damage (asphyxia) 2. To deter unnecessary intervention ( prematurity operative deliveries ) WHICH FETUSES SHOULD BE ASSESSED ALL FETUSES ? small for gestational : age v postdates maternal hypertension, Diabetes antepartum hemorrhage FM’ s etc..... The “high risk” pregnancy
WHAT IS TEST LOOKING FOR ? FETAL HYPOXIA BEFORE ASPHYXIA PLACENTAL FAILURE Poor growth movmt, liquor Poor CTG
The essential characteristics of asphyxia (hypoxic acidemia) are: • umbilical cord arterial pH < 7.0 • base deficit > 16 • Apgar score 0 – 3 for > 5 minutes • neonatal neurologic sequelae (e.g.,seizures, hypotnia, coma) • evidence of multiorgan system dysfunction in the immediate • neonatal period.
Baseline 120 - 160 b.p.m Variability > 5 b.p.m Accelerations present DECELERATIONS EARLY VARIABLE LATE pH sampling normal > 7.25 borderline 7.25 - 7.2 deliver < 7.2 FETAL HEART RATE IN LABOUR
Early decels Early decelerations
Percentage distribution of acidity states in different groups of cardio- tocographical findings according to the HAMMACHER score.
EFM + scalp sampling vs intermittent auscultation in labour (6 trials reviewed) Effect on: Odds Ratio (95% CI) Treatment: ControlAll caesarean sections Caesareans for fetal distress Caesareans for failure to progress Operative vaginal deliveries Apgar score <7 at one minute Apgar score <4 at one minuteAdmission to special care nursery Neonatal seizures All perinatal deaths Intrapartum deaths All operative deliveries General anaesthesiaCerebral palsyCerebral palsy after neonatal seizureLow Bayley mental development index Low Bayley psychomotor index . . . . . . 0.1 0.3 0.5 1 2 4 10 Treatment better Treatment worse
AN IDEAL TEST ? 1. A simple screening test performed in early pregnancy to see whether or not a risk exists. 2. Low rate of false positives and false negatives 3. Cheap 4. Safe 5. Painless 6. Not anxiety inducing for mom 7. Fully assessed
OTHER TESTS CORDOCENTESIS FETAL ECG INFRA RED CONTINUOUS pH
ARE TESTS ANY USE ? Need randomized trials but poor oucomes are infrequent Usually a normal test will result in a favourable outcome
Characteristics or associated findings with late decelerations include all of the following except: a) they may be seen in patients with pre-eclampsia b) they may be associated with respiratory alkalosis c) they are associated with a decreased utero placental blood flow d) they often are accompanied by decreased PO2 e) they usually are accompanied by an increased PCO2