Pregnancy loss is the death of an unborn baby at any time during pregnancy. It is estimated that pregnancy loss occurs in over half of all early pregnancies. Most of these occur so early that the mother does not even know she is pregnant. Although 15 to 20 percent of diagnosed pregnancies are lost in the first or second trimesters of pregnancy, nearly all occur during the first trimester. Only about 1 percent of diagnosed pregnancies are lost after 16 weeks. Pregnancy loss includes:
Blighted ovum - the egg is fertilized but never develops into an embryo
Miscarriage - early pregnancy loss, also called spontaneous abortion
Ectopic pregnancy - the development of the fetus outside the uterus, in a fallopian tube, the cervical canal, or the pelvic or abdominal cavity
Molar pregnancy - an abnormal development of placental and fetal tissues, occurring in about one in 1,000 to one in 1,500 pregnancies
Stillbirth - when the fetus dies before birth
The vast majority of pregnancy losses are due to genetic or chromosomal abnormalities. However, other factors can also play a role in pregnancy loss. These include, but are not limited to, the following:
Abnormal embryo development
Hormone problems in the mother including low levels of progesterone or abnormal thyroid function
Diabetes in the mother (especially in women who have poorly-controlled blood glucose levels)
Abnormalities of the uterus including scar tissue inside the uterus, abnormal formation or shape of the uterus, or myomas (fibroid tumors)
Incompetent cervix - the opening of the uterus cannot stay closed during pregnancy
Infection including organisms such as cytomegalovirus (CMV), mycoplasma, chlamydia, and ureaplasma, as well as listeriosis and toxoplasmosis
Anti-fetal antibodies - the mother's immune system recognizes the fetus as a foreign body and rejects it
Autoimmune diseases - conditions such as lupus erythematosus in which the body makes antibodies against one's own normal body chemicals. Other autoimmune problems include antiphospholipid antibody syndrome.
Exposure to toxic substances and chemicals such as anticancer drugs (studies are conflicting about the relationship of substances such as anesthetic gases, alcohol, and caffeine to pregnancy loss; exposure to video display terminals, or computer screens, has not been shown to be related to pregnancy loss)
Some women have recurrent problems in which pregnancy loss occurs over and over, usually three or more times. It is often difficult to find a cause for recurrent losses and couples may need additional testing for genetic or chromosomal problems.
Fortunately, most pregnancy losses are usually isolated events. A woman with a spontaneous early pregnancy loss has an 80 to 90 percent chance of a normal pregnancy the next time she conceives.
Some pregnancy losses do not cause any problems, while others may be very serious and life threatening for the mother, if untreated. However, the most difficult part for most families is the emotional stress of the loss itself.
The loss of a baby at any time in pregnancy can be emotionally and physically difficult for the mother and other members of the family. For some families, the timing of the loss in the pregnancy may make the experience more or less difficult. For example, an early loss, before the mother even knew she was pregnant, may not be as stressful as a loss later in pregnancy, such as after feeling fetal movement or seeing the fetus on ultrasound examination. However, parents may have strong feelings and sadness whenever a loss occurs.
Parents often experience a grief reaction to a loss, including feelings of the following:
Shock, numbness, denial, and confusion
Anger, guilt, searching, and yearning
Disorientation, depression, withdrawal, or lack of energy
These are normal responses to loss and may take months and sometimes years to work through. Experience with grieving families has found the following to be helpful:
Seeing or holding (this is especially important in later pregnancy losses and with babies who die with a birth defect)
Remembrances (including a lock of hair, hand or footprint, photographs, naming of the baby)
Counseling (with a professional who is experienced in bereavement counseling)
Holding a memorial or funeral service
Vaginal bleeding is the most common symptom of pregnancy loss. In later pregnancy, a woman with a stillborn may no longer feel fetal movements. However, each type of loss has specific symptoms. Also, each woman may exhibit different symptoms or the symptoms may resemble other conditions or medical problems. Always consult your physician for a diagnosis.
In addition to a complete medical history and physical examination, diagnosis of pregnancy loss is usually based on laboratory tests, with reported symptoms aiding in the diagnosis. Tests used to diagnose pregnancy loss may include:
Pregnancy blood tests for the hormone human chorionic gonadotrophin (hCG)
Ultrasound - a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs.
Specific treatment for pregnancy loss will be determined by your physician based on:
Your pregnancy, overall health, and medical history
Gestational age of the fetus
Your tolerance for specific medications, procedures, or therapies
The type of pregnancy loss
Your opinion or preference
Once pregnancy loss occurs, the uterus must be emptied of all the fetal tissues to prevent further complications. Counseling and support of the family are important. Your physician can help you find resources and support organizations that can help after pregnancy loss.