[miscarriage]

Information for TTC Couples...

Written by TTC Couples.

 

Medical Definitions: Pregnancy and Pregnancy Loss

In memory of Robert Moreau Phipps, stillborn on 9/17/96 due to trisomy 18


The definitions on this page were compiled by Patty Phipps with assistance from several other members of the soc.support.pregnancy.loss newsgroup. Thank you to all who assisted.





A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z


Note: Different terms are "medically" applied to a baby at different points in time during pregnancy, ie, embryo, fetus. However, in recognition of the fact that all of us have lost a baby, the term "baby" is used throughout the glossary without regard to the gestational age.




A

Abortion: (elective, therapeutic, or voluntary) Deliberate ending of a pregnancy by medical intervention. (But medical personnel will also use this term for a miscarriage, which is involuntary, calling it a "spontaneous abortion.")
Abruptio placentae: a condition in which the placenta separates from the inner wall of the uterus before the baby is born. Normally the placenta does not begin separating from the uterus until after birth has occurred, but if this process occurs before or during labor, the baby's lifeline for oxygen and nutrients is cut off at the source (the mother's body). Women who have 1 early placental separation leading to a stillbirth have a 10% chance of experiencing a second abruption. The chances are increased to >25% for women who have abruptions in 2 pregnancies. In most cases, there is no way to predict or prevent an abruption.
Alloimmune factors: natural killer cells, leukocyte antigen cross match. Alloimmune factors can lead to pregnancy loss in two different ways. First, the body fails to recognize a pregnancy, and second, there is an abnormal immunological response to the pregnancy. A patient may be tested for leukocyte antibodies, natural killer cells, and embryo toxic factor. Possible treatments are intravenous immunoglobulin (IVIg) or paternal white blood cell immunization. This area of reproductive medicine is considered controversial.
Alpha fetoprotein: a protein produced by the baby that can be measured prenatally, by taking a tube of your blood, to identify possible neural tube disorders and other potential problems, such as Down's Syndrome or anencephaly. A similar test is the triple screen. These tests are not really "positive" or "negative" but rather give you a risk profile for neural tube disorders, Down's Syndrome, etc.
Amniocentesis: the removal of a sample of amniotic fluid by means of a needle inserted through the mother's abdominal wall; used for genetic and biochemical analysis of the baby.
Amniotic fluid: the liquid surrounding and protecting the baby within the amniotic sac throughout pregnancy.
Amniotic sac: the membrane within the uterus that contains the baby and the amniotic fluid.
Anencephaly: a fatal congenital condition in which most or all of the baby's brain and skull are absent. The overall risk for this is 1:1000 but rises to 1:100 for women with a prior baby who had this condition. Folic acid may prevent this condition.
Anomaly: a physical malformation or abnormality.
Antibody: a substance produced in the body that attacks bacteria and viruses.
Anticardiolipin antibody (ACA): an antibody directed against cardiolipin. These are one of the antiphospholipid group of antibodies. They are the most widely accepted and tested for immune factor. Approximately 80% of patients who have an antiphospholipid antibody problem will test positive for anticardiolipin antibodies, but the remaining 20% will test positive for one of the other six antiphospholipid antibodies. These antibodies can cause a miscarriage or stillbirth and can be tested for by a blood sample.
Antinuclear antibody (ANA): an antibody showing an affinity for cell nuclei; this antibody is found in a high proportion of people with lupus (systemic lupus erythematosus), rheumatoid arthritis, and certain collagen diseases, and in about 1% of normal individuals. If you have systemic lupus erythematosus, it can be transmitted through the placenta to the baby, resulting in heart problems.
Antiphospholipid antibody (APA): a group of antibodies that includes lupus anticoagulant and anticardiolipin antibodies. There are seven antibodies included in a test for antiphospholipid antibodies: anticardiolipin antibodies, phosphoethanolamine, phosphoinositol, phosphatidic acid, phosphoglycerol, phosphoserine, and phosphocholine. May cause a false-positive syphilis test. Can cause strokes, blood clots in the legs, and pregnancy loss.
Autoimmune disease: the process in which the body's defense system acts against its own tissues, causing damage.
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B

Basal body temperature (BBT): your temperature when taken in the morning, upon awakening and before beginning any activity. Used to predict ovulation.
Bicornate uterus: a congenital malformation of the uterus in which it is divided internally to some degree by a septum (a membrane) and appears to have two "horns." A known and treatable cause of pregnancy loss.
Blighted ovum: An embryo that has stopped developing and is no longer viable. Pregnancy hormones are produced by the placenta and an egg is fertilized, but the sac that is supposed to contain the fertilized egg is empty, no baby has developed, and the pregnancy is miscarried.
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C

Calcification, placental: a condition in which excessive calcium in the placenta interferes with its functions.
Cerclage: a surgical method for closing an incompetent cervix during pregnancy to prevent premature delivery.
Cervix: the neck of the uterus; Pap smears are taken from the cervix.
Cesarean section: Delivery of the baby through an incision into the skin of the abdomen, the underlying tissues, and the uterus.
Chemical pregnancy: an early loss that ends before the next period is due. There are usually no pregnancy symptoms, but a blood test can reveal small amounts of the pregnancy hormone HCG.
Chlamydia: a bacteria associated with various diseases of the eye and urogenital tract; may be transmitted by sexual contact. This is the most common infection passed from mother to baby; the baby may develop pneumonia (often a mild case) and eye infections. Although the best time to treat the mother for Chlamydia is before pregnancy, antibiotics can be administered during pregnancy to prevent infant infection. Antibiotic ointment used at birth protects the newborn from chlamydial eye infection.
Chorionic villus sampling: a prenatal test in which a soft, thin tube is inserted through the cervix, or a needle through the abdomen, to the chorionic villi, the embryonic tissue that forms the placenta, to withdraw a tissue sample for chromosomal and genetic analysis. This can be performed as early as 10-12 weeks' gestation.
Chromosome analysis: an analysis in which cells are studied to look for abnormalities. Testing a baby may show if there is a chromosomal reason for the pregnancy loss, which causes about 50% of miscarriages. Testing the parents can help determine if there is an underlying chromosomal problem that increases the chances of repeated losses, which occurs in about 3% of couples with multiple (recurrent) pregnancy loss.
Clomid: a brand name for clomiphene citrate, a synthetic hormone that stimulates the pituitary and ovulation. Another brand name is Serophene.
Clomiphene citrate: See "Clomid."
CMV: See "cytomegalovirus."
Complete miscarriage/complete abortion: an early loss in which all of the products of conception (including the baby, the sac, and the forming placenta) are expelled from the uterus.
Cone biopsy: the surgical removal of a cone-shaped wedge of tissue from the cervix for microscopic analysis, in cases of a very abnormal Pap smear.
Cord accident: Any problem with the umbilical cord that causes distress or death of the baby (the cord is wrapped tightly around the baby's neck, cord prolapse [in which part of the umbilical cord is presented before the baby at delivery, potentially causing the baby's death because the cord becomes compressed between the baby and the mother's pelvis, cutting off the baby's oxygen supply], etc.).
Cordocentesis: Transabdominal blood sampling of the fetal umbilical cord, performed under ultrasound guidance. Used to test for certain abnormalities.
Corpus luteum: the small yellowish body of cells that forms after ovulation each month and occupies the space formerly occupied by the egg. It produces progesterone and estrogen and is programmed by nature to disintegrate in about 14 days. When it does, diminishing hormone levels trigger menstruation. In pregnancy, the corpus luteum, sustained by the pregnancy hormone HCG, continues to grow and produce progesterone and estrogen to nourish the baby until the placenta takes over. In most cases, it starts to shrink about 6 or 7 weeks after the last menstrual period and ceases to function at about 10 weeks.
Cytomegalovirus (CMV): a group of viruses that cause enlargement of cells of various organs. Infection in a baby in utero can cause jaundice, high-tone deafness, eye problems, malformation, or fetal death.
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D

D&C: dilation and curettage. A procedure in which the cervix is dilated and the endometrium (the inner wall of the uterus) is scraped to remove tissue remaining after a miscarriage, or the tissue is removed by suction. Usually performed between conception and 12 weeks of pregnancy.
D&E: dilation and evacuation. A procedure in which the cervix is dilated and the baby and placenta are removed. Usually performed between the 14th and 20th weeks of pregnancy. Induced labor can be an alternative to a D&E and will result in an intact baby who can be held, viewed, etc, as opposed to the results of a D&E.
DES: see "diethylstilbestrol."
DIC (disseminated intravascular coagulation): a condition in which the blood will not clot correctly, often leading to life-threatening bleeding. Can occur in some cases of placental abruption.
Diethylstilbestrol (DES): a synthetic, nonsteroidal estrogenic compound. Currently, it is sometimes used after sex to prevent implantation of the fertilized egg. Women whose mothers took DES during pregnancy (at a time when it was wrongly thought to prevent threatened miscarriage) can pass it along to their unborn children, causing stillbirth or birth defects. This was banned by the US FDA in 1971 for use in pregnant women.
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E

Eclampsia: the final stage of toxemia syndrome/preeclampsia/eclampsia. It is signaled by the occurrence of one or more convulsions, not attributable to other cerebral conditions such as epilepsy, in a patient with preeclampsia. These are often preceded by spiking blood pressure, seriously increased levels of protein in the urine, and exaggerated reflex reactions, as well as severe headache, nausea or vomiting, irritability, restlessness, and twitching, upper abdominal pain, visual disturbances, drowsiness, fever, or rapid heartbeat.
Ectopic pregnancy: a pregnancy occurring elsewhere than in the uterus, most often in a fallopian tube. Symptoms includes spasmodic, crampy pain with tenderness starting on one side and often spreading throughout the abdomen; pain may worsen on straining of the bowels, coughing, or moving. Often, brown vaginal spotting or light bleeding, intermittent or continuous, may precede pain by several days or weeks. Sometimes nausea and vomiting, dizziness or weakness, shoulder pain, and/or rectal pressure may be experienced. Getting to the hospital immediately is important. Unless the fallopian tube has irreparable damage, it is usually possible to save it, either by surgery or medication.
Elective abortion: the voluntary termination of a pregnancy for non-medical reasons.
Embryo: the developing baby from conception to about the end of the second month. After that point, the baby is called a fetus.
Endocrine: the system of glands that secrete hormones.
Endocrinologist: a doctor who specializes in disease of the endocrine or hormone system.
Endometrial biopsy: the removal of a small sample of uterine lining (endometrium) through the cervix, done for laboratory analysis between the 21st and 25th days of the menstrual cycle. Helps determine evidence of ovulation.
Endometriosis: a condition in which pieces of the endometrium (uterine lining) are located outside the uterus; often results in severe pain and infertility.
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F

Fetus: The baby from the end of the eighth week until birth.
Fibroid tumors (myomas): Nonmalignant growths within the wall of the uterus that may expand during pregnancy. Most common in women over 35 years of age. Occasionally, these cause problems, increasing slightly the risk of ectopic pregnancy, miscarriage, placenta previa, abruptio placenta, premature labor, premature rupture of the membranes, stalled labor, fetal malformation, and breech and other more difficult to deliver fetal positions.
FISH test: fluorescence in situ hybridization test. A method of chromosome evaluation done with amniotic fluid. The results are usually available in about 3 days and can show evidence of disorders such as trisomy.
Follicle: (mature ovarian follicle) a small sac in the ovary in which the egg develops.
Follicular phase: the first half of the menstrual cycle, prior to ovulation. During this phase, the follicles grow and the eggs mature until ready to be released.
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G

Genetic counseling: the advice offered by experts in genetics on the detection, consequences, and risk of recurrence of chromosomal and genetic disorders.
Gestation: the period of fetal development in the womb from implantation to birth.
Gestational diabetes: carbohydrate intolerance during pregnancy that usually resolves itself after delivery. This is the most common pregnancy complication. Can usually be controlled through diet and, if necessary, medication. About 3% of pregnancies are complicated by diabetes.
Gonadotropins: the pituitary hormones that stimulate the reproductive system (follicle-stimulating hormones).
Gonorrhea: a contagious inflammation of the genitals. Can cause conjunctivitis, blindness, and serious generalized infection in the baby delivered through an infected birth canal. Drops of silver nitrate or an antibiotic ointment can be squeezed into the eyes of the newborn at birth as an extra precaution if the mother has had gonorrhea.
Gynecologist: a doctor who specializes in the diseases and the routine physical care of the reproductive system of women.
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H

Habitual aborter: a rather insensitive term for a woman who has repeated miscarriages. See "habitual miscarriage."
Habitual miscarriage: the recurrent spontaneous loss of a baby.
HCG (human chorionic gonadotropin): A hormone produced by the placenta throughout pregnancy and necessary for maintenance of normal gestation. The blood test called beta subunit of HCG is used to diagnose pregnancy. HCG is also given to infertility patients to help burst follicles and to sustain the corpus luteum. In some cases, following levels of beta-HCG helps to determine if the pregnancy is viable. It should increase about 66% every 48 hours in the first few months of pregnancy.
HELLP Syndrome: a type of severe preeclampsia involving Hemolysis (alteration, dissolution, or destruction of red blood cells in such a manner that hemoglobin, the red protein of blood, gets into the medium in which the cells are suspended), Elevated Liver function, and Low Platelets. Immediate delivery of the baby may be required to preserve the life of the mother.
Hemorrhage: profuse, life-threatening bleeding.
Hepatitis B & C: Hepatitis B is a virus disease with a long incubation period (usually 50 to 160 days), usually transmitted by injection of infected blood or blood derivatives or by use of contaminated needles, etc. Hepatitis C is one of the principal types of hepatitis contracted after a blood transfusion. Both types may be transmitted from an infected mother to her unborn child.
Heparin: a "blood thinner" given as an injection to prevent blood clots from forming. Sometimes used to treat patients with a history of antiphospholipid syndrome.
Herpes: any of several inflammatory viral diseases of the skin characterized by clusters of vesicles (blisters). Herpes is an infection that can be harmful to pregnancy. It is passed on through skin-to-skin contact. Simplex 1 is usually seen in the form of mouth sores, while simplex 2 includes sores on the genitalia. Simplex 2 can cause serious health problems or the death of a baby if the baby is vaginally delivered while the mother has active herpes on the genitals; therefore, active herpes on the genitals during labor often requires a Cesarean section. Simplex 1 can cause early health problems; people with mouth sores should therefore not be allowed to kiss your child. Active herpes can also delay infertility treatments such as in vitro fertilization.
Hydatidiform mole: see "Molar pregnancy."
Hypoplastic left heart syndrome: an underdevelopment of the left side of the heart in an infant; often fatal.
Hypoplastic uterus: an underdeveloped uterus.
Hypothyroidism: diminished production of thyroid hormone, leading to clinical manifestations of thyroid insufficiency, including low metabolic rate, tendency to gain weight, somnolence, and sometimes myxedema (severe hypothyroidism). Hypothyroidism can lead to infertility or miscarriage by disrupting the balance of hormones, especially estrogen, leading to a thin uterine lining and ovulatory dysfunction.
Hysterosalpingogram: a procedure in which a dye is introduced into the uterine cavity and coursed through the uterus and fallopian tubes while x-ray pictures are taken to identify scarring, blockage, or other reproductive problems.
Hysteroscopy: visual instrumental inspection of the uterine cavity. A small optical instrument is inserted into the cervix so the doctor can visualize the lining and contour of the uterus, including any fibroid tumors or uterine malformations. Also called uteroscopy.
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I

Immunology: a science that deals with the immune system.
Immunological: anything that pertains to the body's natural defenses or immunity against disease. Immunological factors for pregnancy loss include antiphospholipid antibodies, lupus anticoagulant, antinuclear antibodies, and antithyroid antibodies.
Impaired pregnancy: a baby that is abnormal due to environmental, genetic, chromosomal, or unknown causes.
Implantation (also called nidation): the process by which the fertilized egg attaches to the uterine lining. Usually occurs around 1 week after the egg is fertilized.
Implantation failure: failure of the fertilized egg to properly implant in the uterine lining.
Incompetent cervix: one that opens prematurely under the pressure of the growing uterus and baby. It is believed responsible for 20% to 25% of all second-trimester miscarriages. (See also "cerclage.")
Incomplete miscarriage/incomplete abortion: an early loss in which some products of the pregnancy remain inside the uterus. Often requires a D&C for removal.
Induction of labor: the process, not always successful, in which labor is started by artificial means due to a pregnancy complication.
Infertility: the inability to conceive after 1 year of unprotected sex. Repeated consecutive pregnancy losses without a live birth may also be referred to as infertility.
Interrupted pregnancy: a pregnancy in which labor is induced before the end of the nine-month term.
Intrauterine growth retardation (IUGR): a condition in which the baby does not develop at the rate that it should. There are many different potential causes of IUGR, including poor maternal health or dietary/lifestyle habits, birth defects, DES exposure, and progesterone deficiency.
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J

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K

Karyotype: the chromosomal characteristics of a cell.
Karyotyping: chromosomal analysis of cells obtained by amniocentesis. Karyotyping can only determine if specific chromosomal abnormalities are present in the person tested (for instance, a balanced translocation), but having a normal karyotype does not lessen a person's chances of having a chromosomal problem in their baby (since most such problems are "accidental" and not the result of a chromosomal abnormality in a parent).
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L

Laminaria: a rod made of kelp (seaweed) that when placed in the cervical canal absorbs moisture, swells, and gradually dilates the cervix. Used to help induce labor.
Laparoscopy: a procedure performed under general anesthesia in which an optical instrument, the laparoscope, is inserted through a small incision in the abdominal wall, enabling the doctor to see the fallopian tubes, uterus, and ovaries directly.
Laparotomy: incision into the abdominal wall.
Lupus: an inflammatory connective tissue disease of unknown cause that occurs chiefly in women, is characterized by fever, skin rash, and arthritis, often by acute anemia, by small hemorrhages in the skin and mucous membrane, by inflammation of the pericardium, and in serious cases by involvement of the kidneys and central nervous system. If needed for arthritic symptoms or by women with the lupus anticoagulant, daily doses of aspirin and the steroid prednisone seem to reduce overall risk of pregnancy complications. Pregnancy complications in women with lupus can include blood clotting problems and a high risk of preterm delivery.
Lupus anticoagulant: an antiphospholipid antibody causing elevation in partial thromboplastin time (the time needed for plasma to form a clot after the addition of calcium and a phospholipid reagent; used to evaluate the clotting system), associated with venous and arterial thrombosis (clotting within an artery or vein).
Luteal phase defect: a somewhat controversial condition in which the menstrual cycle is abnormal during its second half (after ovulation; a short second half of the cycle could mean that the egg will not implant correctly because the uterus has not been prepared sufficiently to receive it). Too little progesterone is produced after ovulation, affecting the menstrual cycle and the ability to sustain a pregnancy.
Luteinizing hormone (LH): a hormone secreted by the pituitary during the entire menstrual cycle, with a peak just before ovulation. May be given therapeutically in infertility conditions. LH is the hormone that urine home-testing kits use to predict ovulation.
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M

Methotrexate: a toxic anticancer drug that is an analogue of folic acid and an antimetabolite. Used as an antineoplastic agent (to attack abnormal tissue growth). Sometimes used to treat ectopic and molar pregnancies.
Midwife: a person who assists women in childbirth.
Miscarriage: a lay term describing spontaneous loss of pregnancy before the middle of the second trimester (20 weeks). (After this point, the event is labeled a preterm birth because the baby is capable of life outside the womb, with support.) The medical term for miscarriage is actually "abortion," and many doctors and technicians may use this term instead.
Missed miscarriage/missed abortion: an early loss in which the baby has died but remains in the uterus, along with the placenta and other elements of conception, without being expelled.
Molar pregnancy (trophoblastic disease): the fertilization of an egg without a nucleus. A baby (usually anomalous) may or may not be present, and the placenta develops into a nonmalignant tumor called a hydatidiform mole. The layer of cells that line the gestational sac and normally give rise to the chorionic villi convert into a mass of clear, tapioca-like vesicles instead of into a healthy placenta. The fertilized egg then deteriorates. Probably caused by a chromosomal abnormality in the fertilized egg. A continuous or intermittent brownish discharge is the prime symptom. A molar pregnancy is treated by a D&C and sometimes methotrexate.
Monosomy: the absence of one chromosome of a pair.
Mycoplasma (T-strain mycoplasma): a microscopic organism thought to be responsible for pregnancy loss.
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N

Neonatal death: the death of a baby within 28 days of live birth.
Neural tube defect (NTD): a birth defect of the brain and/or spinal cord.
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O

Obstetrician: a physician specializing in pregnancy and delivery.
Ovary: the female organs that produce sex hormones and ova (eggs).
Ovulation: the release of a mature, unfertilized egg from the ovary.
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P

Pelvic inflammatory disease (PID): infection and inflammation of the woman's pelvic organs. Thought to be a cause of some cases of infertility.
Perinatal doctor/perinatologist: a doctor specializing in treating the baby and mother during pregnancy, labor, and delivery, particularly when the mother and/or baby are at a high risk for complications.
Pitocin (oxytocin): a drug (given intravenously) used to induce labor.
Pituitary: a gland located at the base of the brain that secretes a number of important hormones related to normal growth and development and fertility.
Placenta: the spongy, vascular organ that supplies the baby with maternal blood and nutrients through the umbilical cord.
Placenta previa: a condition in which the placenta is located over the cervix, creating a risk of hemorrhage during labor and delivery. Such pregnancies can usually be delivered safely through cesarean section.
Placental abruption: See "abruptio placentae."
Polycystic ovaries/polycystic ovarian syndrome (PCO/PCOS): a condition in which many ovarian cysts enlarge the ovaries and cause infertility. Commonly characterized by obesity, menstrual abnormalities, infertility, abnormal facial and body hair, and enlarged ovaries.
Preclinical pregnancy: an early loss that ends before the next period is due. There are usually no pregnancy symptoms, but a blood test can reveal small amounts of the pregnancy hormone HCG. Also called "chemical pregnancy."
Preeclampsia: development of hypertension (high blood pressure) with proteinuria (an excess of urinary protein) or edema (an excessive amount of fluid in the tissues), or both, due to pregnancy or the influence of a recent pregnancy; it usually occurs after the 20th week of gestation but may develop before this time in the presence of trophoblastic disease. High blood pressure can be dangerous to the mother and can lead to early induction of labor as a means of protecting the mother's life. Also called "toxemia." In some cases, preeclampsia may lead to eclampsia or to HELLP syndrome.
Pregnancy-induced hypertension (PIH): see "preeclampsia."
Premature: a baby born before 37 weeks' gestation.
Preterm: labor that begins between the 20th and 37th weeks of pregnancy.
Progesterone: a female hormone important during pregnancy and menstruation. It is secreted by the corpus luteum to prepare the endometrium for implantation and later by the placenta during pregnancy to prevent rejection of the developing baby.
Prostaglandin: Also called by various more specific names, such as dinoprost; a hormone produced by the body that may be administered to induce labor.
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R

Recurrent pregnancy loss/recurrent miscarriage/recurrent spontaneous abortion: repeated pregnancy losses. Testing can be done to try to determine the cause of such losses. If an underlying condition is found, the woman may need to be treated for the problem before a pregnancy can be carried to term.
Reproductive endocrinologist: An endocrinologist specializing in reproductive disorders.
Rh factor: any of one or more genetically determined antigens present in the red blood cells of most persons and capable of inducing intense immunologic reactions. Some women develop a sensitization to Rh during pregnancy. If a woman is Rh negative and her husband is Rh positive, she is a candidate for Rh incompatibility problems. After the first pregnancy, the Rh factor enters the Rh-negative mother's circulatory system during the delivery (or miscarriage) of a child who has inherited the Rh factor from his father. The mother's body then produces antibodies against it. If she becomes pregnant with another Rh-positive baby, the antibodies cross the placenta and attack the baby's red blood cells, causing mild to serious anemia in the baby. The medication Rhogam (called "Anti-D" in Britain and New Zealand) is given to prevent these problems.
Rhogam: an immunization given to Rh-negative women after a miscarriage, stillbirth, or live birth to prevent production of antibodies in any Rh-positive babies they may have in future pregnancies.
Rubella (German measles): a viral disease characterized by headache, fever, rash, and inflammation of the throat. Infection in a pregnant mother can damage the baby. The risks are greater the earlier in the pregnancy that the mother contracts the illness.
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S

Secondary infertility: the inability of a couple to conceive after a previous successful pregnancy.
Septic miscarriage: an early loss complicated by uterine infection, usually from an incomplete miscarriage.
Serophene: see "Clomid."
Sexually transmitted disease (STD): any disease that can be transmitted by sex, such as syphilis.
SIDS (Sudden Infant Death Syndrome): abrupt and inexplicable death of an apparently healthy infant; various theories have been advanced to explain such deaths (for example, sleep-induced apnea, laryngospasm, overwhelming infectious disease), but none has been generally accepted or demonstrated at autopsy. Also called crib death or cot death.
Small for gestational age: a baby whose measurements (height, weight, etc) are below the norm for its gestational age. Can be a sign of a problem with the pregnancy or the baby.
Sonogram (also called ultrasound): a visualization of internal organs achieved by bouncing sound waves into the area to be examined (for example, a pregnant woman's abdomen). A level 1 ultrasound is usually done to date a pregnancy. A level 2 ultrasound is used for more specific diagnostic purposes. Sonograms can detect a number of problems, but like all medical tests, they are not 100% perfect.
Spina bifida: an abnormality in the development of the spine that can cause severe neurological impairment and paralysis.
Spontaneous miscarriage/spontaneous abortion: any unplanned termination of a pregnancy in the first 20 weeks.
Stillbirth: the death of a baby of at least 20 weeks' gestation before delivery.
Syphilis: a contagious and chronic venereal disease that can produce rashes and lesions. In the baby, it can cause bone and tooth deformities, progressive nervous system damage, stillbirth, and eventual brain damage. Antibiotic treatment of the infected mother before the fourth month of pregnancy, when the infection usually begins to cross the placental barrier, will almost always prevent damage to the baby.
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T

Tamoxifen: an estrogen antagonist used to treat infertility caused by a failure to ovulate properly (it is also used to treat postmenopausal breast cancer). The dose for infertility depends on the menstrual cycle. In women who are having regular periods, the treatment usually begins by taking 20 mg on the 2nd, 3rd, 4th, and 5th days of the menstrual cycle. If this is not successful, the dosage might be increased to 40 mg daily and then to 80 mg if required. In women who do not have regular periods, the treatment can be started on any day.
Termination: the ending of a pregnancy by choice by induced labor (resulting in a live birth or stillbirth) or abortion.
Tetraploidy: cells containing 4 sets of chromosomes instead of the normal two.
Therapeutic abortion: a termination (due to severe abnormalities or when the mother's health is at risk) of a pregnancy not intended to result in a live birth.
Threatened miscarriage: an incidence in which certain symptoms, such as vaginal bleeding or severe cramping, occur during pregnancy. The symptoms may stop or may progress to a miscarriage.
Toxemia: see "preeclampsia."
Toxoplasmosis: infection by disease caused by a bacteria that invades the tissues and may seriously damage the central nervous system, especially of infants. It also may be transmitted by a mother to her unborn child, resulting in abnormalities such as water on the brain (hydrocephalus), the development of jaundice shortly after birth, etc. Often found in cat feces, which is why doctors ask their pregnant patients to refrain from changing kitty litter during pregnancy.
Transvaginal ultrasound: an ultrasound examination performed by means of inserting a probe into the vagina. This can produce better images in early pregnancy that could be obtained with conventional abdominal sonograms.
Trendelenburg position: the position in which the patient lies on her back with the bed tilted so that her knees and hips are higher than her head. Used to help prevent preterm delivery.
Trimester: one of the 3-month periods into which a pregnancy is divided.
Triploidy: the presence of 3 chromosomes instead of 2.
Trisomy: a cell with an extra chromosome. There are various types of trisomies depending on which chromosome is affected. Trisomy 8 is characterized by abnormal face/head, short wide neck but narrow cylindrical trunk, and multiple joint and digit defects. Trisomy 13 (also called trisomy D syndrome and Patau's syndrome) is characterized by mental retardation and malformed ears, cleft lip or palate, defects of the eyes, small jaw, extra fingers or toes, cardiac defects, convulsions, renal anomalies, umbilical hernia, malrotation of the intestines, and other anomalies (not all patients have all signs of this syndrome), and is usually fatal within 2 years. Trisomy 18 (also called Edward's syndrome) is usually fatal within 2 months and is characterized by mental retardation, abnormal skull shape, low-set and malformed ears, small jaw, cardiac defects, short sternum, abnormal flexion of the fingers (for instance, the fetus is shown with clenched fists), and diaphragmatic or inguinal hernia. Trisomy 20 is characterized by profound mental retardation, abnormally large mouth and tongue, minor abnormalities of the ears, and other skeletal defects. Trisomy 21 (Down's syndrome) includes abnormalities such as mental retardation, retarded growth, flat face with short nose, prominent skin folds, small low-set ears, thickened tongue, broad hands and feet, stubby fingers, and others. Heart disease in Down's syndrome patients is common, and Alzheimer's disease by age 40 is almost inevitable. The majority of babies with trisomies are miscarried.
Trophoblastic disease: trophoblastic cells normally contribute to the formation of the placenta and are the pathway through which the baby receives nutrients from the placenta. See "molar pregnancy."
Tubal pregnancy: see "ectopic pregnancy."
Turner's Syndrome: a genetically determined condition that is associated with the presence of only one complete X chromosome and no Y chromosome and that is characterized by a female phenotype with underdeveloped and infertile ovaries. When these women grow up, they are often infertile but have very normal mental acuity.
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U

Ultrasound: see "sonogram."
Ureaplasma: a bacteria (from the same family as mycoplasma) found in the genitourinary tract; in women, it may be associated with reproductive failure. It is thought that it may cause an inflammation of the uterine lining that can result in miscarriage (usually an early loss due to implantation problems). Can also contribute to pelvic inflammatory disease in women and production of anti-sperm antibodies in men.
Uterus/Womb: the female reproductive organ that contains the developing baby.
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V

Viable/viability: the ability of an infant to survive outside the womb.
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Copyright © 1997 by Patty Phipps.
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Last revision: July 10, 1997