Your obstetrician is your primary source of care. There are several indications for “high-risk” pregnancy. When your pregnancy is considered high-risk, your OB will refer you to Perinatal Diagnostic Center . A perinatalogist will consult with you, offer relevant diagnostic tests and coordinate your care with you and your OB for the duration of you pregnancy. At Perinatal Diagnostic Center, Inc., we strive to improve pregnancy outcomes and ensure optimal health for every woman and infant.
- High resolution ultrasound services
- Prenatal diagnostic testing
- Genetic counseling
- Pre-conceptual and pregnancy consultations
- First trimester screening
- Patient's who have pregnancy's that are considered “high-risk” are or have:
- Advanced Maternal Age (AMA)
- Multiple Gestation
- Personal or family history of genetic disorders
- Personal or family history of congenital defects
- Medical issues such as Diabetes Mellitus
- Hypertension in pregnancy
- Abnormal thyroid function
- RH factor
- Repeated pregnancy loss
- Cervical incompetence
- Teratogen exposure
- Antiphospholipid antibody syndrome (APS)
- Abnormal results from genetic screening or diagnostic test
Advanced Maternal Age (AMA)
A patient who will deliver after turning 35 years old is considered to be at a higher risk of having a child with Down syndrome. The
risk is 1 in 365 at age 35 and increases yearly from there. The risk is 1 in 109 at age 40. Genetic counseling is advised for the AMA patient and genetic testing will be offered.
Women aged 35 and over are more likely to be diabetic or develop gestational diabetes.
Miscarriage, stillbirth and low birth weight infants are more common in women over 35.
Twin, triplet, and quadruplet (and so on) pregnancies are considered high risk because of the complications often associated with them. Factors such as whether or not the fetuses share a placenta or an amniotic sac are important to determine early on. When the fetuses share an amniotic sac there is the possibility that they may tangle in each other's umbilical cords. Twin-to-twin transfusion syndrome (TTTS) is a term you may have heard before and it refers to fetuses that share a placenta. These fetuses may not receive the same amount of nutrition resulting in one fetus not growing adequately and may result in demise of one the fetuses.
Preterm labor and/or delivery is another concern associated with multiple gestations. A premature baby may have varying degrees of low birth weight, physical complications, and irreversible mental conditions and have increased risk of death.
Patient's with multiple gestation also are at higher risk for developing hypertension and diabetes.
Large chromosomal abnormalities, such as extra or missing chromosomes or chromosome fragments, can be detected by a standard laboratory procedure called karyotyping. Karyotyping involves the identification and analysis of all 46 chromosomes from a cell. In this systematic display, abnormalities in chromosome number and structure are apparent.
In cases involving more subtle abnormalities, on the scale of single genes or even DNA bases, highly specialized techniques are required. Such methods rely on the fundamental principles of the genetic code, and specifically on the ability to generate a matching, or complementary segment of DNA. Structurally, DNA is composed of two single strands attached to each other to form a double helix. The bases of one strand always bind to the bases of the other in a specific fashion: A pairs with T, and G with C. If one knows the sequence of the bases in one strand, one can deduce the complementary sequence of bases in the other strand. Based on a known sequence of DNA, scientists can create a synthetic copy of the matching strand, called a DNA probe that will then bind, or hybridize to a specific gene within a chromosome.
In a method called fluorescence in situ hybridization (FISH), DNA probes are labeled with colored fluorescent tags that light up so one can see specific chromosomes or genes under a microscope. Using FISH, subtle genetic abnormalities that cannot be detected by standard karyotyping are readily identifiable. This procedure typically takes 24-48 hours to complete. Additionally, using a panel of multi-colored DNA FISH probes, abnormal chromosome copy numbers can be seen.
Birth defects are defined as abnormalities of structure, function, or body metabolism that are present at birth. These abnormalities lead to mental or physical disabilities or are fatal. There are more than 4,000 different known birth defects ranging from minor to serious, and although many of them can be treated or cured, they are the leading cause of death in the first year of life. Birth defects can be caused by genetic, environmental, or unknown factors.
Structural or metabolic defects are those that result when a specific body part is missing or formed incorrectly or when there is an inborn problem in body chemistry.
Heart defects, congenital heart defect (one that's present at birth).
Special form of sonography (looking at the fetus by means of sound waves) called echocardiography can accurately identify many heart defects. If certain heart problems, such as a heart that is beating too fast or too slowly, are diagnosed before birth, medications may restore a normal heart rhythm before the fetal heart starts to fail. In other cases, where the heart defect can't be treated before birth, knowing that it exists enables doctors to be ready to give the baby the treatment it needs as soon as it is born.
Spina bifida, is a birth defect that involves the incomplete development of the spinal cord or its coverings. The term spina bifida comes from Latin and literally means "split" or "open" spine.
Hypospadias, a condition in which the opening of the male urethra (where urine exits from the penis) is in the wrong place.
Defects caused by congenital infections result when a mother gets an infection before or during the pregnancy.
(None of these infections affect 100% of babies whose mothers are infected during pregnancy. If the mother is infected during early pregnancy, rubella carries the highest risk for birth defects - approximately 20%.)
Rubella — commonly known as German measles or 3-day measles — is an infection that primarily affects the skin and lymph nodes. It is caused by the rubella virus ( not the same virus that causes measles), which is usually transmitted by droplets from the nose or throat that others breathe in. It can also pass through a pregnant woman's bloodstream to infect her unborn child. As this is a generally mild disease in children, the primary medical danger of rubella is the infection of pregnant women, which may cause congenital rubella syndrome in developing babies.
cytomegalovirus (CMV), Infection with cytomegalovirus (CMV), a member of the herpes virus family, is very common. CMV is mainly a problem for certain high-risk groups, including:
- unborn babies whose mothers become infected with CMV during the pregnancy
- children or adults whose immune systems have been weakened by disease or drug treatment, such as organ transplant recipients or people infected with HIV
Syphilis is an infection that is usually acquired through sexual contact with another infected person. Syphilis can be frightening because if it goes untreated, it can lead to serious health problems and increase a person's risk for HIV, the human immunodeficiency virus that causes AIDS. A pregnant woman can avoid passing syphilis on to her unborn child by getting tested and treated for the disease during pregnancy.
Chickenpox - Pregnant women and anyone with immune system problems should not be near a person with chickenpox. If a pregnant woman who hasn't had chickenpox in the past contracts it (especially in the first 20 weeks of pregnancy), the fetus is at risk for birth defects and she is at risk for more health complications than if she'd been infected when she wasn't pregnant. If she develops chickenpox just before or after the child is born, the newborn is at risk for serious health complications. There is no risk to the developing baby if the woman develops shingles during the pregnancy. If a pregnant woman has had chickenpox before the pregnancy, the baby will be protected from infection for the first few months of life, since the mother's immunity gets passed on to the baby through the placenta and breast milk.
Other causes of birth defects include alcohol abuse by the mother and Rh disease, which can occur when the mother's and baby's Rh factors (the "positive" or "negative" part of a person's blood type) are different. Although a few medications can cause problems, of the 200 most commonly prescribed drugs, none is associated with a significant risk of birth defects.
Abnormal Numbers of Chromosomes (Trisomies and Monosomies)
Genetic problems can happen for many different reasons. Sometimes, a mistake occurs during cell division, causing an error in the chromosome number either before or shortly after conception. The developing embryo then grows from cells that have either too many chromosomes or too few.
In trisomy , for example, there are three copies of one particular chromosome instead of the normal two (one from each parent). Down syndrome, trisomy 18 (Edwards) syndrome, and trisomy 13 (Patau) syndrome are all examples of this type of genetic problem. (Down syndrome (DS) is a condition in which extra genetic material causes delays in the way a child develops, and often leads to mental retardation. It affects 1 in every 800 babies born.)
Trisomy 18 syndrome affects one out of every 8,000 newborns. Children with this syndrome have a low birth weight and a small head, mouth, and jaw. Their hands typically form closed fists with abnormal finger positioning. They may also have malformations involving the hips and feet, heart and kidney problems, and mental retardation. Only about 5% of these children live longer than 1 year.
Trisomy 13 syndrome affects one out of every 20,000 newborns. This syndrome causes cleft lip( birth defect in which the tissues of the mouth or lip don't form properly during fetal development), flexed fingers with extra digits, hemangiomas (blood vessel malformations) of the face and neck, and many different structural abnormalities of the skull and face. It can also cause malformations of the ribs, heart, abdominal organs, and sex organs. Long-term survival is unlikely but possible.
In monosomy , another form of number error, one member of a chromosome pair is missing. There are too few chromosomes rather than too many.
Deletions, Translocations, and Inversions
sometimes it's not the number of chromosomes that's the problem. Instead, one or more chromosomes is incomplete or abnormally shaped. In both deletions and microdeletions , for example, some small part of a chromosome is missing. In a microdeletion, the missing part of a chromosome is usually so small that it amounts to a single gene or only a few genes. Some important genetic disorders caused by deletions and microdeletions include: Wolf-Hirschhorn syndrome (affects chromosome 4); Cri-du-chat syndrome (chromosome 5); DiGeorge syndrome (chromosome 22); and Williams syndrome (chromosome 7).
In translocations (which affect one out of every 500 newborns), bits of chromosomes shift from one chromosome to another, whereas in inversions (which affect about one out of every 100 newborns), small parts of the DNA code seem to be snipped out and reinserted flipped over. Translocations may either be inherited from a parent or arise spontaneously in a child's own chromosomes. Both translocations and inversions typically cause no malformations or developmental problems in the children who have them. However, when children with either translocations or inversions grow to adulthood and wish to become parents, they may have an increased risk of miscarriage or chromosome abnormalities in their own children.
Genetic problems also occur when abnormalities affect the sex chromosomes. Normally, a child will be a male if he inherits one X chromosome from his mother and one Y chromosome from his father. A child will be a female if she inherits a double dose of X (one from each parent) and no Y. Sometimes, however, children are born with only one sex chromosome (usually a single X) or with an extra X or Y. Turner syndrome is the name of the disorder affecting girls born with only one X chromosome, whereas boys with Klinefelter syndrome are born with XXY or XXXY.
Sometimes, too, a genetic problem is X-linked , meaning that it's carried by the X chromosome. Fragile X syndrome, which causes mental retardation in boys, is one such disorder. Other diseases that are carried by genes on the X chromosome include hemophilia and Duchenne muscular dystrophy (Muscular dystrophy (MD) is a genetic disorder that gradually weakens the body's muscles. It's caused by incorrect or missing genetic information that prevents the body from making the proteins it needs to build and maintain healthy muscles.). Females may be carriers of these diseases, but because they also inherit a normal X chromosome, the abnormal X may be canceled out. Males, on the other hand, only have one X chromosome and are almost always the ones who have the disease.
Some genetic problems are caused by a single gene that's present but altered in some way. Such changes in genes are called mutations . When this is the case, the number and appearance of the chromosomes are often entirely normal. To pinpoint the defective gene, scientists use sophisticated DNA screening techniques. Some examples of genetic illnesses caused by a single problem gene include: cystic fibrosis (Cystic fibrosis (CF) is a genetic disorder that particularly affects the lungs and digestive system and makes a child more vulnerable to repeated lung infections.), sickle cell anemia, Tay-Sachs disease, and achondroplasia (a type of dwarfism , is a condition characterized by short stature. Technically, that means an adult height of 4 feet 10 inches or under).
Although experts originally believed that no more than 3% of all human diseases were caused by errors in a single gene, new research suggests that this may be an underestimate. Within the last 2 years, scientists have discovered genetic links to many different diseases that weren't originally thought of as genetic, including several different types of cancer.
Oncogenes (Cancer-Causing Genes)
Researchers have identified 20 to 30 cancer-susceptibility genes that greatly increase a person's odds of getting some form of malignancy. For example, a gene has been identified on chromosome number 9 that may be linked to a common skin cancer called basal cell carcinoma. This gene, labeled PTC or patched, may someday be important in screening for this type of cancer. Another gene, called HNPCC, is carried by one out of every 300 Americans and may greatly increase an individual's chance of getting colon cancer. And the doubly dangerous gene called BRCA-1 seems to give women an 85% chance of developing breast cancer, as well as a 50% chance of ovarian tumors.
Other Genetically Linked Diseases
Altered genes may play a role in the development of many other devastating illnesses. Parkinson's disease, for example, may be linked to a gene on chromosome number 4, and multiple sclerosis may be linked to alterations in a gene on chromosome number 6. Alzheimer's disease, linked to a gene on chromosome 19, can already be diagnosed (in some cases) by screening for that altered gene, although such screening is viewed by many as controversial.
Although heart disease and diabetes appear to be related to simultaneous changes in many different genes, the first of these may already have been identified. According to the American Heart Association, this gene may be an artery-clogging gene that almost doubles the risk of fatty deposits blocking the coronary arteries. Having the gene may also triple someone's chances of getting adult-onset diabetes. Like heart disease, depression and other mental illnesses may be the result of alterations in several genes at once. Although no specific genes have yet been found, doctors estimate that 48% to 75% of depression is inherited, and they believe that they'll find the exact genetic mechanism very soon.
It's important to note that much of the newest information from genetic research has not yet been translated into useful screening tests. However, experts predict that this will soon change, and they estimate that the number of available genetic tests will increase tenfold in the next decade.
Environmental causes of birth defects have more to do with the mother's health and exposure to chemicals or diseases. When a mother has certain infections, such as rubella, during pregnancy, it can cause birth defects. Alcohol abuse by the mother causes fetal alcohol syndrome, and certain medications taken by the mother can cause birth defects.
Multifactorial birth defects are caused by a combination of genetic and environmental factors and include neural tube defects and cleft lip and palate.
Gestational Diabetes Mellitus (GDM)
GDM is a specific type of diabetes that only pregnant women get. To support the fetus as it grows, the mother's body makes hormones. In some women, these hormones work against their bodies, making them less able to make the insulin needed to get energy from body cells. Without this insulin, the level of sugar in the mother's blood starts to build up, which, if left untreated, can cause health problems for both mother and fetus. Even though it usually goes away after the baby is born, GDM can affect the health of both mother and baby later in life. For instance, women who have GDM during pregnancy have a 40 percent greater chance of developing type 2 diabetes later in life. And, babies born to mothers with GDM are at greater risk than babies born to other mothers of developing type 2 diabetes or being obese (extremely overweight) later in life. Because babies born to mothers with GDM tend to be larger than average, GDM can also affect the way a baby is delivered. In some cases, the safest way to deliver a baby from a mother with GDM is by surgery, called cesarean section.
Although many pregnant women with high blood pressure have healthy babies without serious problems, high blood pressure can be dangerous for both the mother and the fetus. Women with pre-existing, or chronic, high blood pressure are more likely to have certain complications during pregnancy than those with normal blood pressure. However, some women develop high blood pressure while they are pregnant (often called gestational hypertension).
The effects of high blood pressure range from mild to severe. High blood pressure can harm the mother's kidneys and other organs, and it can cause low birth weight and early delivery. In the most serious cases, the mother develops preeclampsia--or "toxemia of pregnancy"--which can threaten the lives of both the mother and the fetus.
Abnormal thyroid function
Hyperthyroidism and Hypothyroidism
About 2 percent of pregnant women have a thyroid disorder, though many have no symptoms. In some cases, the thyroid produces too much thyroid hormone (hyperthyroidism); in others, not enough (hypothyroidism)
When the thyroid becomes inflamed, it will first emit large quantities of thyroid hormone into the bloodstream (hyperthyroidism). During this phase, most women are unaware of any symptoms, which are often mild and short-lived. However, once this initial phase passes, a woman either recovers completely or has sustained damage to her thyroid. If the thyroid gland was damaged, this damage, together with a depleted reservoir of thyroid hormones, can lead to hypothyroidism (underactive thyroid). This condition, too, may also clear up or result in further damage and complications.
The following are the most common symptoms of hyperthyroidism or hypothyroidism that accompany postpartum thyroiditis. However, each women may experience symptoms differently. Symptoms may include:
experiencing muscle weakness
loss of memory
cannot tolerate cold weather
cramps in the muscles
loss of concentration
Rh disease can occur when a pregnant woman who has an Rh-negative blood type carries a baby with Rh-positive blood. The woman's body senses the difference and develops antibodies to "fight" the different type blood. Since the antibodies are almost never formed until late in the pregnancy, the pregnancy in which the antibodies are formed is usually not at risk, but subsequent babies may be. In future pregnancies, an Rh-positive baby could be at risk of severe anemia during pregnancy. The anti-Rh antibodies will go from the mother through the placenta and into the baby's bloodstream, where they can destroy the baby's red blood cells. However, a medication called RhoGam is available. The RhoGam destroys the fetal cells before they can "signal" the mother's body to form antibodies to the Rh factor on the fetal cells.
Repeated Pregnancy Loss
Miscarriage is the loss of a pregnancy before 20 weeks. It occurs in 10 percent to 15 percent of all known pregnancies. Most miscarriages occur in the first 3 months of pregnancy. When pregnancy loss occurs two or more times in a row, it may be called repeated miscarriage.
There are many reasons for repeated miscarriage. In at least one half of all repeated miscarriages the cause cannot be found. Sometimes a miscarriage can be linked to chromosomal problems in the fetus, medical conditions in the woman, or problems with the woman's uterus. There are tests to help your doctor determine what caused the miscarriage and in some cases treatment is available to avoid problems in future pregnancies.
Sometimes premature effacement (shortening of the vaginal portion of the cervix and thinning of the walls) and dilation of the cervix is not caused by labor, but rather by structural weakness in the cervix itself. This is called cervical incompetence. The weakness can result from a number of conditions, most due to prior injury to the cervix or resulting from an inherited physical condition of the cervix. Risk factors for an incompetent cervix are: a history of incompetent cervix with a previous pregnancy, surgery, cervical injury, DES (diethylstilbestrol) exposure, and anatomic abnormalities of the cervix. A prior abortion can, for example, damage the cervix. Other causes of cervical weakness include cervical cautery (to remove growths or stop bleeding) and cone biopsy (removal of a cone-shaped section of tissue for study to detect possible precancerous growth). Prior to pregnancy or during the first trimester, there is usually no method to determine whether the cervix will eventually be incompetent.
Diagnosis is made by medical history, physical exam, and ultrasound study. A pregnancy test will also be performed. Once the problem of incompetence is diagnosed, the condition may be treatable through a surgical procedure called cerclage. The cerclage is usually removed just before childbirth so that the patient can give birth vaginally. In some cases, the cerclage may be left in place, and the baby is then delivered by cesarean section.
Teratogen is any medication, chemical, infectious disease, or environmental agent that might interfere with the normal development of a fetus and result in the loss of a pregnancy, a birth defect, or a pregnancy complication.
There are a variety of teratogens that are relatively common. Some examples are listed, but there are other teratogens which are not on this list.
- Social Drugs: alcohol, cocaine, cigarettes
- Medications: Seizure medications (such as Dilantin, Valproic Acid, Tegretol), Accutane, thalidomide, chemotherapy, lithium
- Environmental Agents: organic solvents, chemicals, lead, anesthetic gases, organic mercury
- Infectious Diseases: rubella, cytomegalovirus, genital herpes, toxoplasmosis, Fifth's disease, chicken pox (varicella)
- Other: diabetes, radiation, hyperthermia (high fever)
If you have had exposure to a medication or chemical during your pregnancy, including some of those listed above, you may want to get additional information on the possible effects on your pregnancy.
Antiphospholipid antibody syndrome (APS)
Antiphospholipid antibody syndrome (APS) is an illness that involve the immune system, and causes increased clotting of the blood. Normally antibodies, chemicals made by the immune system, are helpful in fighting germs or viral infections from outside the body. However in APS, the immune system makes antibodies that cause blood to clot abnormally. This may cause problems with the pregnancy.
The manifestations of APS are variable. Most people will not have more than one of these problems.
- Recurring miscarriage
- Insufficient function of the placenta causing poor growth of the baby and/or inability of the baby to tolerate labor
- Blood clot in an artery or large vein either during the pregnancy, or up to six weeks after the baby is born
A very rare APS condition exists of a severe postpartum illness with fever and heart, lung and kidney failure and multiple blood clots.
Patients with APS are more prone to blood clots during pregnancy and up to 6 weeks after pregnancy. The blood clots may migrate to the lungs which is a very serious and life threatening event. Frequent office visits will be needed to screen for preeclampsia and ultrasound examinations every 3-4 weeks to check the growth of the baby.
It appears that maternal morbidity is substantially reduced if conception takes place when the disease is in remission. Lupus nephritis may present during pregnancy and, if this is the case, Lupus is usually severe. Even though disagreements exist as to whether pregnancy has an adverse effect on the course of Lupus and Lupus nephritis, there are convincing reports that the frequency of flare is higher during pregnancy. This exacerbation during pregnancy may be wide-ranging, causing increased proteinuria and leading to renal failure. Pre-eclampsia with hypertension and proteinuria may be mistaken for the flare of lupus. Very severe exacerbation of lupus in pregnancy may require termination of pregnancy. It is generally accepted that if exacerbation requires termination, the disease will not necessarily improve, but it is unlikely to become worse.
Pregnancies with women with Lupus and Lupus nephritis are also marked by an increase in fetal loss and increased fetal morbidity. Since IgG antibodies cross the placenta, there is a risk of lupus in the new-born. These manifestations of lupus disappear in 3-6 months. Some babies have congenital heart block associated with anti-SSA antibodies in the maternal serum and the baby's heart lesions may be permanent.
Abnormal results from genetic screening or diagnostic test
The first step is often to have an ultrasound exam. This test can check on the age of the baby and look at the brain, spinal cord, kidneys and heart for any problems. Another test that you might have is called amniocentesis. This test checks the fluid around the baby. The results of these tests will help your doctor decide if your baby might have a problem.