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  • Trisomy 18 – Edwards Syndrome

    WHAT IS IT?  Trisomy 18 is also sometimes referred to as Edwards syndrome  It is unusual for a baby to have trisomy 18 without multiple birth defects seen during a detailed prenatal ultrasound (some of which are detailed below)   Present in approximately 1 in 5000 live births  Approximately 70% of trisomy 18 pregnancies result in loss between first trimester to term  […]

  • Renal Pyelectasis on Prenatal Ultrasound

    WHAT IS IT?   Renal pyelectasis (also called hydronephrosis or dilation) describes the condition where the tube that carries urine from the fetal kidney to the bladder is distended and wider than expected Diagnosis is based on prenatal ultrasound measurements  Renal pyelectasis is seen in 1 to 3 per 100 pregnancies during second trimester   Most cases will resolve on […]

  • Exposure to Radiation During Pregnancy

    WHAT ARE THE EFFECTS OF RADIATION DURING PREGNANCY?  When considering the effects of radiation during pregnancy  Radiation exposure used for most x-rays, CT scans or nuclear imaging is usually at a dose that is lower than amount known to be associated with risk to the pregnancy If these tests are necessary during pregnancy, they should […]

  • Screening for Neural Tube Defects

    WHAT IS IT?   Neural tube defects are serious birth defects of the brain and spine.  Taking folic acid (a type of B vitamin) prior to pregnancy and continuing this vitamin once pregnant has been shown to prevent neural tube defects.   The neural tube starts as a flat structure along the baby’s back that folds up in […]

  • Drugs in Pregnancy and Breastfeeding – Helpful Resources 

    STARTING AND STOPPING MEDICATIONS IN PREGNANCY While it is important to not start any new medications in pregnancy without speaking to your Obstetric provider, it is just as important to not stop medications without a discussion   A basic principle is that a healthy mother is important to give a baby the best chance possible of […]

  • Prenatal Screening for Down Syndrome and other Chromosomal Disorders

    Standard Screening NIPS/NIPT Key Points The key to understanding prenatal ‘screening’ tests is to focus on the word ‘screening’.  Screening tests can not tell you for sure whether or not the baby will have a genetic problem at birth. Only a diagnostic test like amniocentesis or CVS (see ‘Related Topics’ below) can tell you that with […]

  • The Chromosome – More about DNA and How It Is Packaged 

    WHAT IS IT?  A chromosome is the structure for the efficient packaging of DNA that is found in the cellular nucleus. Humans have 23 chromosome pairs, typically one chromosome in each pair is inherited from the mother and one from the father, for a total of 46 chromosomes DNA  DNA is the ‘instruction manual’ for the cell and […]

  • Spinal Muscular Atrophy

    WHAT IS IT?  In the US, all women who are considering or who are currently pregnant are offered a test that looks for whether a pregnancy may be at risk for a disorder called ‘spinal muscular atrophy’ (SMA). SMA is a severe progressive disorder caused by a loss of cells in the spinal cord, which leads to the […]

  • Fragile X Syndrome

    WHAT IS IT?  Fragile X syndrome is a serious genetic disorder that is associated with significant findings, including developmental delay and autism.  Prenatal screening for Fragile X should be offered based on a professional assessment of family and personal history   Fragile X occurs in approximately 1 in 4000 males and 1 in 8000 females and is an important cause of inherited developmental […]

  • Prenatal Screening for Cystic Fibrosis

    WHAT IS IT?  Genetic screening for cystic fibrosis (CF) has been recommended in the US for over a decade  CF screening should be offered to all pregnant women or those considering pregnancy  CF is caused by a change in the CFTR gene   The CFTR gene instructs a cell to build a protein that helps control how salts move through cells  Damage […]

  • Prenatal Carrier Screening Including Hemoglobinopathies

    SUMMARY: The most important point when considering prenatal genetic screening in pregnancy is that most often, these tests are looking for potential disorders in the baby by identifying otherwise healthy parents who are ‘carriers’. Babies are not at risk unless both parents are carriers. New technologies can now test for many disorders at the same […]

  • Turner Syndrome

    WHAT IS IT?  Turner syndrome is sometimes referred to as 45,X, monosomy X, Turner’s syndrome or Ullrich-Turner syndrome  Present in 1 of 2500 live births  Normally, most individuals have two sex chromosomes   The mother will always send along one X chromosome to the baby  The father will send along either an X or Y chromosome  The baby will, […]

  • Intellectual Disability Defined

    WHAT IS IT?  Intellectual Disability (formerly known as mental retardation)  Official definition   Characterized by significant limitations both in intellectual functioning (IQ <70-75) and behaviors that cover many everyday social and practical skills; originating before age 18  It is no longer defined by IQ alone, rather IQ is only part of the evaluation  UNDERLYING CAUSE:  Intellectual disability can have […]

  • Klinefelter Syndrome

    WHAT IS IT?  Klinefelter syndrome is also known as XXY syndrome   Klinefelter syndrome is present in 1 in 500 to 1 in 1000 newborn males  Normally, most individuals have two sex chromosomes The mother will always send along one X chromosome to the baby  The father will send along either an X or Y chromosome  […]

  • Trisomy 13 – Patau Syndrome

    WHAT IS IT?  Trisomy 13 is also sometimes referred to as Patau syndrome  It is very unusual for a baby to have trisomy 13 without multiple birth defects seen during a detailed prenatal ultrasound (some of which are detailed below)   Most affected individuals do not survive fetal/newborn life   Approximately 50% of Trisomy 13 pregnancies end in loss […]

  • Hypoplastic Left Heart Syndrome

    WHAT IS IT?  Hypoplastic left heart syndrome (HLHS) can be diagnosed prenatally, using ultrasound   There are 4 chambers (sections) that make up the heart  Two ventricles (lower chambers) and two atria (upper chambers)    HLHS will appear on an ultrasound report when the lower chamber of the left side of the heart – the left ventricle – […]

  • What Does a ‘Short Fetal Humerus’ Mean?

    WHAT IS IT?  A short humerus, or upper arm bone, will appear on a prenatal ultrasound report when the measurement of the bone is smaller than expected for a particular gestational age The length of the baby’s humerus will change and grow over time, and while there is an average measurement, some babies will have longer bones, and […]

  • Transposition of the Great Arteries

    WHAT IS IT?  Transposition of the Great Arteries (TGA) is a serious heart condition that can be detected using prenatal ultrasound, although it can be difficult to identify and may not be diagnosed until after delivery    In a normal heart The pulmonary artery carries deoxygenated (low oxygen) blood to the lungs Oxygenated (high oxygen) blood returns […]

  • Ventricular Septal Defect

    WHAT IS IT?  A ventricular septal defect (VSD) describes a “hole” in the wall/septum between the two major heart chambers (sections) and may be detected during pregnancy using ultrasound   There are 4 chambers that make up the heart  Two ventricles (lower chambers) and two atria (upper chambers)    VSD will appear on an ultrasound report when there is a […]

  • Tetralogy of Fallot

    WHAT IS IT?    Tetralogy of Fallot (TOF) is a congenital heart defect, that occurs in approximately 1 in every 2,500 live births and accounts for 7 to 10% of all congenital heart defects  TOF derives its name (‘tetra’logy) from being a combination of 4 serious heart disorders that together cause abnormal blood flow that can be […]

  • Second Trimester Nuchal Fold

    WHAT IS IT? The nuchal fold (NF) thickness is a measurement performed on prenatal ultrasound, and is the distance from the outer edge of the bone at the back of the head to the outer edge of the overlying skin. A nuchal fold thickness is only performed in the second trimester and should not be […]

  • Short Femur on the Second Trimester Ultrasound Report

    WHAT IS IT?  A short femur, or upper leg bone, will appear on a prenatal ultrasound report when the measurement of the bone is smaller than expected for a particular gestational age.   Femur length is one of the key measurements used to measure a baby’s growth during pregnancy and is therefore part of a standard ultrasound in the second […]

  • Ashkenazi Jewish Background and Genetic Carrier Screening

    WHAT IS IT?    Professional organizations recommend testing individuals of Ashkenazi (Central/Eastern European) Jewish (AJ) heritage who are pregnant or considering pregnancy    AJ screening entails offering a group of genetic tests often called ‘panels’   All people carry a few variants (changes in their DNA, also called ‘mutations’) that may impair the function of an important enzyme or other types of proteins  […]

  • Nuchal Translucency and First Trimester Screening

    WHAT IS IT?  Nuchal translucency (NT) describes a fluid filled space seen behind the fetal neck on ultrasound and is obtained during a first trimester ultrasound.  This fluid filled space, usually a normal finding, represents fluid that is circulating around the fetus (developing baby) early in pregnancy. While every fetus will have this NT space, […]

  • Gastroschisis – What Does it Mean?

    WHAT IS IT?   Gastroschisis is the presence of bowel loops floating in the amniotic fluid outside the abdomen   There is no membrane covering the bowel loops, therefore organs are exposed to amniotic fluid and can be damaged  The opening in the abdomen is usually just off to the side of where the umbilical cord connects Incidence is […]

  • Omphalocele Explained

    WHAT IS IT?  Omphalocele, or exomphalos, is the protrusion of internal organs (may include intestines, liver and other abdominal organs) through the abdominal wall of the fetus and has a thin covering  Occurs where the umbilical cord  attaches to abdomen   Abdominal organs are normally found outside the body between 6 to 10 weeks of development   Omphalocele occurs when the organs fail to return to the abdomen […]

  • Single Umbilical Artery, or the ‘Two Vessel Cord’

    WHAT IS IT?  Typically, there are 3 blood vessels in the umbilical cord  1 umbilical vein, which takes blood with high levels of oxygen from mother to the baby   2 umbilical arteries, that bring the blood back to the mother after the oxygen is taken out of the blood and used by the baby   A single umbilical artery and single […]

  • Echogenic Intracardiac Focus

    WHAT IS IT?   An echogenic intracardiac focus (EIF) is a relatively common ultrasound finding, even in otherwise normal fetuses  EIF is not a heart defect, but rather represents calcified deposits in the fetal heart muscle    Calcium can cause bright spots on ultrasound   WHAT TO EXPECT:   Your doctor may suggest the following to determine the best management plan for your pregnancy    […]

  • Second Trimester Echogenic Bowel

    WHAT IS IT?  As the baby develops during pregnancy, the bowel (intestines) can sometimes appear bright on prenatal ultrasound ‘Echogenic’ or ‘bright’ bowel is not, by itself, a significant finding, unless the bowel appears very bright on ultrasound  Studies differ on how common this finding is, but echogenic bowel may be present in up to 1% […]

  • Duodenal Atresia Seen on Prenatal Ultrasound

    WHAT IS IT?  Duodenal atresia results from failure of the duodenum, the section of the bowel between the stomach and small intestine, to form normally.   The incidence of duodenal atresia is 1/5000 – 1/10,000 live births (considered ‘rare’)   Excess amniotic fluid is present in 80% of cases of duodenal atresia  The developing baby actually breaths and swallows amniotic fluid (important for […]

  • Prenatal Diagnostic Testing: Amniocentesis and Chorionic Villus Sampling

    WHAT IS IT?  ‘Invasive prenatal diagnostic testing’ usually refers to amniocentesis (analysis of amniotic fluid cells) or chorionic villus sampling (placental cells)   Chorionic Villus Sampling (CVS)  Tiny pieces of the placenta, called chorionic villi, are tested to check for chromosomal or genetic disorders in the developing baby (or fetus)  Placental DNA usually matches the baby’s DNA as they both start […]

  • 22q11.2 Deletion Syndrome

    WHAT IS IT?  22q11.2 deletion syndrome is referred to by other names such as  22q deletion syndrome, DiGeorge syndrome or Velocardiofacial (VCF) syndrome are alternate references  Approximately 1/3000 to 1/6000 children are born with this disorder  While there may be noticeable characteristic facial features in some affected individuals, this syndrome may be missed at birth and can have life threatening […]

  • Down Syndrome/ Trisomy 21

    WHAT IS IT?  Down syndrome is the most common chromosomal cause of intellectual disability  May affect almost every organ system   Prenatal Ultrasound Findings   Extra fluid or thickening around the neck First trimester: ‘Increased nuchal translucency’  Second trimester: ‘Nuchal fold’ or ‘Nuchal Thickening’    Congenital heart disease (50%)  Duodenal atresia   The section of the bowel that […]

  • Cystic Hygroma Explained

    WHAT IS IT?  Cystic hygroma is a large fluid-filled cavity located behind and around the fetal neck  On ultrasound, a cystic hygroma can extend the length of the fetus   A cystic hygroma is an abnormality of the ‘lymphatic’ system, which is made up of vessels that help circulate fluid around the body   A cystic hygroma can be seen as early […]

  • Prenatal Detection of Clubfoot

    Clubfoot (congenital talipes equinovarus) is one of the most common orthopedic conditions diagnosed on prenatal ultrasound and is found in 1-3 per 1000 infants at birth.  WHAT IS IT?  In a fetus with clubfoot, the sole of the foot is turned in   It occurs twice as often in males compared to females    Can occur in one leg (unilateral) or both legs (bilateral)     […]

  • Cleft Lip and Palate

    WHAT IS IT?  ‘Orofacial clefts’ include cleft lip, cleft palate or combined cleft lip and palate The orofacial clefts   Occur in approximately 1 in 1000 births   Cleft palate alone occurs in approximately 1 in 2000 births  Are more common in Asians and some Native American groups  Are less common in African-Americans  Cleft lip and/or palate is more common in […]

  • Choroid Plexus Cysts – Usually Not a Reason for Concern

    WHAT IS IT? Choroid Plexus   Choroid plexus is a normal structure found in the brain that forms cerebrospinal fluid (CSF)  CSF is also normal and circulates around the brain and spinal cord  Choroid Plexus Cysts  Choroid plexus cysts (also called CPCs)  Can be seen during 2nd trimester ultrasound   Are present in 0.3-3.6% of all pregnancies   Are caused by CSF […]

  • Atrial Septal Defect (ASD)

     WHAT IS IT?   There are 4 chambers (sections) that make up the heart  Two ventricles (lower chambers) and two atria (upper chambers)    An atrial septal defect (ASD) means that there is a hole in the wall (septum) between the two upper chambers   The hole allows blood to flow between the two atria   If the hole is small, there may […]