MISCARRIAGE

Spontaneous interruption of pregnancy called miscarriage. Medical synonym for miscarriage is spontaneous abortion.

World Health Organization (WHO) defines this unsurvivable state as an embryo or fetus weighing 500 grams or less, which typically corresponds to a fetal age (gestational age) of 20 to 22 weeks or less. Miscarriage occurs in about 15% to 20% of all recognized pregnancies; in most cases it occurs before the 13 week of pregnancy. With the development of highly sensitive assays for hCG levels that can detect an early pregnancy even prior to the expected next period, researchers have been able to show that about 65%-70% of all pregnancies (recognized and not-recognized) are lost. Because the loss occurs so early, many miscarriages occur without the woman ever having known she was pregnant.

About 15% of fertilized eggs are lost before the egg even has a chance to implant in the uterus wall. Women would not be able to identify this type of miscarriage. Another 15% of conceptions are lost before eight weeks' gestation. Once fetal heart function is detected in a given pregnancy, the chance of miscarriage is less than 5%.

Miscarriage Causes

Most common causes of miscarriage in the first third of pregnancy (first trimester) are:

• chromosomal abnormalities
• collagen vascular disease (such as lupus)
• hormonal dysfunctions
• diabetes
• infections
• uterus abnormalities
• stress

Chromosomal abnormalities. Certain genetic abnormalities are known to be more prevalent in couples that experience repeated pregnancy losses. These genetic traits can be screened for by blood tests prior to trying to conceive.

Half of the fetal tissue from1st trimester miscarriages contain abnormal chromosomes. This number drops to 20% with 2nd trimester miscarriages.

Chromosomal abnormalities also become more common with aging, and women over age 35 have a higher rate of miscarriage than younger women. Advancing maternal age is the most significant risk factor for early miscarriage in otherwise healthy women.

Collagen vascular diseases are illnesses in which a person's own immune system attacks their own organs. These diseases can be potentially very serious, either during or between pregnancies. In these diseases, a woman makes antibodies to her own body's tissues. Examples of collagen vascular diseases associated with an increased risk of miscarriage are systemic lupus erythematosus, and antiphospholipid antibody syndrome. Blood tests can confirm the presence of abnormal antibodies and are used in the diagnose of these conditions.

Hormonal dysfunctions. Hormones (mainly estrogens and progesterone) are crucial in pregnancy development and any dysfunction can be a cause for pregnancy interruption. Some hormonal diseases can provoke hormonal disturbances - Cushing's Syndrome, thyroid disease, and polycystic ovary syndrome (PCOS). It also has been suggested that inadequate function of the corpus luteum in the ovary (which produced progesterone necessary for maintenance of the very early stages of pregnancy) may lead to miscarriage - "luteal phase defect".

Diabetes generally can be well managed during pregnancy, if a woman and her health care practitioner work closely together. However, if the diabetes is insufficiently controlled, not only is the risk of miscarriages higher, but the baby can have major birth defects. Other problems can also occur in relation to diabetes during pregnancy. Good control of blood sugars during pregnancy is very important.

Infections are recognized as an increased risk for miscarriage. Fetal or placental infection by the offending organism then leads to pregnancy loss. Examples of infections that have been associated with miscarriage include infections by Listeria monocytogenes, Toxoplasma gondii, parvovirus B19, rubella, herpes simplex, cytomegalovirus, and lymphocytic choriomeningitis virus.

Uterus abnormalities (congenital defects, tumors). Normal pregnancy development needs normal uterus size and structure. In some women there can be a tissue bridge (uterine septum), that acts like a partial wall dividing the uterine cavity into sections. The septum usually has a very poor blood supply, and is not well suited for placental attachment and growth. Therefore, an embryo implanting on the septum would be at increased risk of miscarriage.

Some fibroids also can provoke miscarriage. Fibroid tumors are benign growths of muscle cells in the uterus. While most fibroid tumors do not cause miscarriages, some can interfere with the embryo implantation and the embryo's blood supply, thereby causing miscarriage.
Some post-operation uterus scars also can be a problem for normal pregnancy development.
Sometimes surgical procedures also can be a cause for miscarriage such as amniocentesis, cervical procedures even appendectomy.

Stress. There isn't enough evidence to show whether or not stress is a risk factor for miscarriage, but it's a good idea to take time during the day to relax.

Miscarriage Symptoms

The most common symptom of miscarriage is vaginal bleeding. This can vary from light spotting to bleeding that is heavier than your period. You may also see blood clots, a brown discharge, or other tissue that isn't clearly identifiable.

You can often get cramping and pain in your pelvis or back. You may find that the usual symptoms of pregnancy, such as breast tenderness, feeling sick and having to pass urine more frequently than usual, stop unexpectedly.

Sometimes there are no symptoms and your miscarriage may only be discovered in a routine scan.

Miscarriage Prevention

Every pregnancy is at risk of miscarriage; however, if you drink alcohol or smoke, your risk of having one is higher. You can help to reduce your risk of pregnancy problems by eating a balanced diet, losing any excess weight and by not drinking too much alcohol or smoking.

Threatened miscarriage

If you have vaginal bleeding but tests suggest that your pregnancy is still progressing, your doctor may recommend:

	Resting You will be advised to temporarily avoid sexual intercourse (pelvic rest) and heavy activity. Your doctor may recommend bed rest. But most research shows that bed rest does not prevent miscarriage.
	Progesterone You may be treated with the hormone progesterone to help maintain the pregnancy. This treatment, though, may serve only to delay a miscarriage and has not been proved effective for preventing a miscarriage.
	Avoiding non-steroidal anti-inflammatory drugs (NSAIDs) You will be advised to avoid aspirin and other nonsteroidal anti-inflammatory drugs, such as ibuprofen. Use only acetaminophen, such as Tylenol, for nonprescription pain relief.

Treatment of Miscarriage

There is no medical treatment to stop or prevent an inevitable miscarriage. The physician generally directs the woman with symptoms to rest in bed and abstain from sexual intercourse and douching. As noted above, in the case of incomplete abortion, prompt surgical removal of any products of conception is required.

It is normal for a woman to feel depressed by the loss of an expected child and counseling may be very helpful. On the advice of her physician, it is usually safe for her to attempt to conceive a soon time afterward (six to eight weeks later).