1. 產科常見檢查 R 4 蔡曉文

2. Screening for neural tube defects and Down syndrome Screening: identifies individuals whose risk is high for further evaluation. Screening: identifies individuals whose risk is high for further evaluation. Maternal serum AFP screening: 15-22 wks Maternal serum AFP screening: 15-22 wks A confirmed increase in maternal serum AFP to greater than 2.0 to 2.5 MOM indicates increased risk for a fetal NTD or other structural anomaly and warrants further evaluation. A confirmed increase in maternal serum AFP to greater than 2.0 to 2.5 MOM indicates increased risk for a fetal NTD or other structural anomaly and warrants further evaluation.

3. Elevated levels of AFP Neural tube defects Neural tube defects Esophageal or intestinal obstruction Esophageal or intestinal obstruction Cystic hygroma Cystic hygroma Abdominal wall defects- omphalocele, gastroschisis Abdominal wall defects- omphalocele, gastroschisis Urinary obstruction Urinary obstruction Renal anomalies- polycystic or absent kidneys Renal anomalies- polycystic or absent kidneys Low birth weight Low birth weight Oligohydramnios Oligohydramnios Multifetal gestation Multifetal gestation Decreased maternal weight Decreased maternal weight

4. Biochemical screening for Down syndrome Down syndrome: most common cause of congenital mental retardation; VSD, anterior abdominal wall defects. Typical faces. Down syndrome: most common cause of congenital mental retardation; VSD, anterior abdominal wall defects. Typical faces. Combination of maternal age, hCG, AFP and uE3( unconjugated estriol) Combination of maternal age, hCG, AFP and uE3( unconjugated estriol) DS screening was based on maternal age alone and women aged 35 years and over were offered amniocentesis. DS screening was based on maternal age alone and women aged 35 years and over were offered amniocentesis. Utilizes two analytes( hCG ↑, AFP ↓ ) — double test Utilizes two analytes( hCG ↑, AFP ↓ ) — double test Triple test: high hCG, low AFP, and low uE3 Triple test: high hCG, low AFP, and low uE3

5. Ultrasonography The mid-trimester anomaly scan: for structural abnormality at 18-20 wks. The mid-trimester anomaly scan: for structural abnormality at 18-20 wks. Cardiac defect: Four-chamber view identify 60% of severe lesions and a complete fetal cardiac scan identifies 75% of all cardiac abnormalities. Cardiac defect: Four-chamber view identify 60% of severe lesions and a complete fetal cardiac scan identifies 75% of all cardiac abnormalities. NTD: 95% of all spina bifida; The recognized association of frontal bone scalloping( lemon sign) and abnormally shaped cerebellum( banana sign) aids the detection of neural tube lesions. NTD: 95% of all spina bifida; The recognized association of frontal bone scalloping( lemon sign) and abnormally shaped cerebellum( banana sign) aids the detection of neural tube lesions.

6. Ultrasonography Gastrointestinal abnormalities: anterior abdominal wall defect( omphalocele and gastroschisis) at the mid-trimester scan Gastrointestinal abnormalities: anterior abdominal wall defect( omphalocele and gastroschisis) at the mid-trimester scan obstruction and atresia is more often diagnosed in late second trimester or the third trimester because of polyhydramnios or an incidental finding of dilated loops of bowel. obstruction and atresia is more often diagnosed in late second trimester or the third trimester because of polyhydramnios or an incidental finding of dilated loops of bowel. Thoracic abnormalities: congenital diaphragmatic hernia may be diagnosed in the second trimester but is usually more apparent in the third; usually left-sided. Thoracic abnormalities: congenital diaphragmatic hernia may be diagnosed in the second trimester but is usually more apparent in the third; usually left-sided.

7. Nuchal fold translucency Edema of the fetal neck, detectable in the first trimester by ultrasound, is associated with cardiac defects, Down syndrome, and other trisomies. Edema of the fetal neck, detectable in the first trimester by ultrasound, is associated with cardiac defects, Down syndrome, and other trisomies. Performed between 10 and 14 wks. Performed between 10 and 14 wks. Training of personnel and scanning time. Training of personnel and scanning time.

8. Amniocentesis Done between 15 and 20 wks; amniotic fluid contains fetal cells shed from the gut and skin. Done between 15 and 20 wks; amniotic fluid contains fetal cells shed from the gut and skin. 1. Chromosomal analysis: most commonly Down syndrome testing for maternal age, high risk serum tests and ultrasound markers. 2. DNA analysis for genetic disease. 3. Enzyme assays for inborn errors of metabolism. 4. Investigation of fetal lung maturity ( lecithin/sphingomyelin ratio or presence of phyophatidyl glycerol) 5. Bilirubin ( for rhesus iso-immunization)

9. Amniocentesis The main risk: miscarriage( <1% procedure- related risk) The main risk: miscarriage( <1% procedure- related risk) Minor complications: transient vaginal spotting, or amniotic fluid leakage(1%), chorioamnionitis. Minor complications: transient vaginal spotting, or amniotic fluid leakage(1%), chorioamnionitis. The risk is higher when the procedure is performed at 14 wks or less( early amniocentesis). The risk is higher when the procedure is performed at 14 wks or less( early amniocentesis). Needle injuries are rare, especially when real- time scanning is used. Needle injuries are rare, especially when real- time scanning is used. Culture failure is rare with a rate of less than 0.5%. Maternal cell contamination occurs in less than 0.2% Culture failure is rare with a rate of less than 0.5%. Maternal cell contamination occurs in less than 0.2%

10. Chorionic villus sampling CVS is performed at 10 to 13 wks; allows earlier and safer methods of pregnancy termination when they are abnormal. CVS is performed at 10 to 13 wks; allows earlier and safer methods of pregnancy termination when they are abnormal. Indications: Indications: 1. Karyotyping when ultrasound findings suggest aneuploidy. 2. DNA analysis, particularly for haemoglobinopathies and recessive or X-linked disorders Complications Complications 1. Pregnancy loss- 2-3% 2. Maternal cell contamination lead to false negative results 3. Limb reduction deformities: before GA 9 wks.

11. Fundal symphyseal height A useful screening method for detection of the baby that is small or large for gestation. A useful screening method for detection of the baby that is small or large for gestation. Third trimester: approximate to the number of the gestation. The variation is 2 from 20-35 wks, 3 from 36-38 wks, and 4 after that. Third trimester: approximate to the number of the gestation. The variation is 2 from 20-35 wks, 3 from 36-38 wks, and 4 after that. Further investigation Further investigation Limitation: multiple pregnancies, maternal obesity, or polyhydramnios. Limitation: multiple pregnancies, maternal obesity, or polyhydramnios.

12. Fetal movement chart The presence of fetal movement is a sign of fetal well-being and occurs in a cyclical pattern. The presence of fetal movement is a sign of fetal well-being and occurs in a cyclical pattern. High risk pregnancies and those where a subjective reduction in movements has already been reported, the use of fetal movement charts( defining normality as 10 movements per day) may be of some benefit. High risk pregnancies and those where a subjective reduction in movements has already been reported, the use of fetal movement charts( defining normality as 10 movements per day) may be of some benefit.

13. Cardiotocography Monitoring fluctuations in fetal heart rate over time and correlating this with any uterine activity. ( after 32 weeks) Monitoring fluctuations in fetal heart rate over time and correlating this with any uterine activity. ( after 32 weeks) Non stress CTG: Non stress CTG: 1. baseline 110-160 beats/min with 2. short-term viability around that baseline of between 5 and 25 beats/min. 3. At least two accelerations should occur within each 20 mins( a rise of at least 15 beats lasting for 15 seconds). 4. No deceleration from the baseline.

14. Cardiotocography Useful means of excluding current fetal hypoxia and acute compromise. Useful means of excluding current fetal hypoxia and acute compromise. The intermediate and long-term prognostic value of CTG is poor. The intermediate and long-term prognostic value of CTG is poor. Not be reactive: hypoxia, anemia, infection, medication, cerebral hemorrhage, maternal metabolic disturbance, chromosomal or congenital malformation. Not be reactive: hypoxia, anemia, infection, medication, cerebral hemorrhage, maternal metabolic disturbance, chromosomal or congenital malformation.