HHHoldorf PhD, MPA, RDMS (Ob/Gyn, Ab, BR), RVT, LRT(AS)

 Lecture one The obstetrical ultrasound examination  Lecture two Genetics and prenatal diagnosis  Lecture three First Trimester Screening for Aneupoloidy  Lecture four The second trimester Genetic sonogram  Lecture five Fetal syndromes  Lecture six Ultrasound examination during the first Trimester  Lecture seven Ultrasound evaluation of fetal biometry and normal fetal growth  Lecture Eight Ultrasound evaluation of Multiple Pregnancies  Lecture Nine Ultrasound evaluation of normal fetal anatomy  Lecture Ten Ultrasound evaluation of the fetal neural axis

 Lecture 11The fetal face and neck  Lecture 12The fetal musculoskeletal system  Lecture 13 Ultrasound evaluation of the fetal thorax  Lecture 14 Ultrasound evaluation of the fetal heart  Lecture 15 Ultrasound evaluation of the fetal Gastrointestinal tract and fetal anterior abdominal wall defect  Lecture 16Fetal Genitourinary Tract

Ob/Gyn outline  Pelvic anatomy  Physiology of the female pelvis  Uterine and Ovarian Pathology  Adnexal Pathology and Infertility  Assessment of the First Trimester 0-12 weeks  Assessment of the Second Trimester weeks  Assessment of the Third Trimester weeks  Fetal Abnormalities  Complications in Pregnancy  Placenta, Amniotic Fluid, and Cord  Patient Care, Preparation, and Technique

 Obstetrical Sonography 1  Lecture 1  The Obstetrical US examination  The Sonography Boards (ARDMS and ARRT) states that 1- 6% of the OB/Gyn questions may be related to patient care techniques.  SUPINE HYPOVOLEMIC SYNDROME (IVC SYNDROME)  This condition occurs when a large, heavy gravid uterus compresses the IVC.  Diminished venous return to the heart may lower blood pressure causing the patient to feel faint, light headed, sweaty or nauseous. A change in patient position, such as turning the patient on her side, will alleviate this problem.

 PATIENT HISTORY  Prior to beginning the sonographic examination, a brief patient history should be obtained.  The findings may alert the Sonographer to a particular area or areas that should be examined more carefully.  The following information should be obtained:

 LMP (Last Menstrual Period) – the first day of the last onset of menses is used.  Pregnancy test – Serum beta hCG (Human Chorionic Gonadotropin) is the most accurate. Serum tests positive as early as 6 days post conception. Urine pregnancy tests may not be positive until 4-6 weeks post LMP.  Clinical problems such as:  Pain  Fever  Vaginal bleeding or discharge

Quick Quiz  Define Gravidity: the total number of pregnancies  Nulli-gravida: a woman who has never been pregnant  Gravida: a pregnant woman  Primigravida: a woman who is pregnant for the first time

 Multigravida: a woman who has been pregnant several times.  The term gravida 4 means what? The woman has had four pregnancies  When reflecting on a patient’s past obstetric history, what are the “categories”? (List them-5 cats)  Time pregnant  Full-term births  Premature births  Abortions  Children currently alive

 Pertinent medical history such as:  Presence of underlying diabetes, hypertension, infections  Previous obstetric problems  History of congenital anomalies in family

 Clinical estimation of duration of pregnancy  A variety of clinical methods are available to estimate the stage of gestation, and most of them rely on the measurement of the fundal height (FH)  The linear distance between the symphysis pubis and the uterine fundus is the fundal height (FH) measurement. Obtain the measurement in CMs and use a chart.

Lecture Two Outline  Teratogenesis:  Congenital malformations are anatomical or structural abnormalities present at birth.  A teratogen is any substance causing abnormal structures in an embryo.  Causes of congenital malformations include:  Genetic factors  Environmental factors  Multifactorial inheritance  Sensitive period concept: Certain structures are sensitive to specific teratogenic agents at given times and only at given times.  Teratogens are divided into three categories:

 Physical Agents  Radiation  Heat: defined as hyperthermia exposure between 4 to 14 weeks (Hot tubs, saunas)  Mechanical factors: uterine anomalies, fibroids, amniotic bands.  Drugs and Chemical Agents  Alcohol (fetal alcohol syndrome)  Antithyroid Drugs : polydactyly, goiter  Coumadin: Encephalocele, anencephaly, spina bifida, CHD, Growth retardation  DES (Diethylstilbestrol): T shaped uteruses in Female offspring  Methotrexate: Absence of frontal bone, growth retardation  Mercury: Microcephaly  Maternal factors  Maternal diseases and conditions: infections, diabetes, sickle cell anemia.

Chromosomal Abnormalities  Can be defined as genetic defects that can be ID’d and diagnosed microscopically. Genetic disease may be the result of”  Abnormal number of chromosomes  Abnormal structure of one or more chromosomes  Single gene defect (unifactorial) inherited one of two ways  Autosomal dominant: one parent is usually affected with the trait and it is transmitted from one generation to another. Genetic expression rarely skips a generation. The probability of transmitting the trait is 50% with each pregnancy.  Autosomal recessive: parents are usually unaffected and the trait may appear to skip a generation. After ID of the genetic defect, the recurrence risk is 25% in each pregnancy.

TERMINOLOGY  Karyotype: The complete set of chromosomes in a cell. May be isolated from a cell, photomicrographed and arranged in pairs for analysis  Euploid: A normal, balanced set of chromosomes (23 sets in humans)  Aneuploid: An unbalanced set of chromosomes (too many or too few)  Phenotype: The entire physical and physiologic makeup of an individual determined both genetically and environmentally.  Genotype: The genetic composition of an individual.

GENETIC TESTS  First trimester Testing: performed between 11.5 and 13.5 weeks of pregnancy:  Two parts: Nuchal translucency scan and a maternal blood test.  Blood test=Free beta –hCG and PAPP-A (Pregnancy associated plasma protein A).  The combination of nuchal translucency measurement and the blood test detects about 85% of fetuses with Down syndrome (Trisomy 21) or Trisomy 18.  The NT is available immediately, the blood test takes about a week.

 When abnormal results are obtained, CVS is offered to determine chromosomal abnormalities. NTD cannot be diagnosed with CVS.  Nuchal Translucency Screening: The nuchal Translucency scan measures the fluid filled area at the back of the neck between 11.5 and 13.5 weeks.  The measurement can be used to calculate the chance that the fetus has Trisomy 21 or 18. It is based on the crown-rump length of the fetus.  Free beta-hCG and PAPP-A: Are produced by the trophoblasitc tissue, and low levels may indicate abnormal implantation, poor placental development, or risk of Trisomy 21.

 Chorionic Villus Sampling (CVS)  Used to provide genetic information about a fetus earlier in gestation. Performed 9 to 12 weeks gestation. Performed either transcervically or transabdominally using direct US guidance. Trophoblasitc cells obtained can be cultured and karyotyped earlier than other tests.

Second Trimester Testing  Multiple Marker Screen  Tests for specific biochemical screening programs include:  Maternal Serum alpha-fetoprotein (MSAFP)  Human chorionic gonadotropin (hCG)  Unconjugated estriol (uE3)  Inhibin-A  Specifically, these markers increase the detection of open neural tube defects (ONTD’s), Down syndrome (Trisomy 21), and  Trisomy 18.  Quadruple screen is used for Trisomy 21

 AFP is a protein produced primarily by the fetal liver.  Elevated MSAFP (> 2 MOM) may be associated with  Wrong dates  Multiple gestations  Open neural tube defects  Ventral wall defects  Other fetal anomalies  Decreased MSAFP is associated with  Wrong dates  Trisomies 13, 18, 21  Fetal demise

 When the MSAFP is not at expected levels, a “level II” sonogram is performed to establish dates, rule out multiple gestations or identify fetal anatomic abnormalities

 Human Chorionic Gonadotropin (hCG) and Unconjugated estriol (uE3) are effective in screening for Down syndrome.  hCG tends to be elevated and uE3 tends to be lower than normal in Down syndrome fetuses.  Inhibin-A is elevated with Down syndrome, and is the most recent maternal serum marker to be included routinely.

 Summary: With Trisomy 18, the maternal serum levels of AFP, hCG, uE3 and Inhibin-A are all decreased.  With Trisomy 21, AFP and uE3 are low while hCG and Inhibin-A are high.

 Amniocentesis  Offered to evaluate amniotic Fluid levels of AFP, acetylcholinesterase *(AChE) levels, and for fetal chromosomal karyotyping. IF EITHER THE AFP OR ACETYLCHOLINESTERASE IS ELEVATED, AN OCCULT NTD IS MOST LIKELY.  Performed around 16 weeks gestation, mostly for women over 35 years of age.  *Enzyme found in neuromuscular (brain) junctions.

Obstetrical Sonography I Lecture 1 homework 1. Is Diagnostic Medical Ultrasound safe? Explain. 2. What are the indications (if any) for an Obstetric ultrasound examination? 3. What are the main items that should be identified in the First trimester ultrasound examination? 4. What are the main items that should be identified in the second and third trimester ultrasound examination? 5. The text refers to Twin Transfusion syndrome: Please define TTS. 6. What are the various fetal presentations which we might consider abnormal? 7. Are those who perform Ultrasound examinations at risk for malpractice suits? Explain.

Lecture 2 Homework Define the following:  Trisomy 21  Trisomy 18  Trisomy 13  Turner syndrome Describe the following:  Alpha-Fetoprotein  Incorporating the importance and consequences of elevated MSAFP  Amniocentesis  CVS Chorionic Villus Sampling  PUBS Peri-umbilical Blood sampling (Fetal Blood sampling)