What is a Spontaneous Abortion?

Spontaneous abortion is substitute term for miscarriage. It means the involuntary loss of pregnancy usually before the 20th or 22nd week of gestation, and it typically occurs very early in the pregnancy. There are estimates suggesting that 50% of pregnancies end in spontaneous abortion, but many of these are never recognized. Failure of a fertilized egg to implant may cause extremely early miscarriage that isn’t ever suspected as a pregnancy.

Of the miscarriages that are recognized as actual pregnancy, most end on or before the 12th week of pregnancy. The rates for miscarriage decline significantly after the 13th week. This is especially the case if the heart is found to be functional. Once heart function is determined, women generally have a 95% chance of not miscarrying. This doesn’t preclude risk for pre-term labor.

There are a number of things that can cause spontaneous abortion. Lifestyle choices like smoking and using drugs may increase risk. Chromosomal abnormalities of the fetus are usually the number one cause, and these aren’t always genetic diseases, but are often simply mistakes that occur in the reproduction of new cells after egg fertilization. When these are severe, they can create a situation where a fetus is not viable, and it dies in utero. The body naturally responds to this by miscarrying.

Other spontaneous abortion causes include abnormalities of the uterus, and exposure to certain diseases and conditions. Often it is unknown why a miscarriage occurs, and if it is a first or second pregnancy, doctors may do no investigation because of the high spontaneous abortion rate. If pregnancy loss occurs after the 20th week, there may be more interest in identifying cause since this is rarer. Doctors tend not to investigate miscarriage cause unless a woman has three of them in succession.

When spontaneous abortion occurs in recognized pregnancies, the main symptoms are cramping or pain in the pelvis, and possibly back, and bleeding from the vagina. Women who are pregnant and who experience vaginal bleeding or cramping should see their doctors immediately. Sometimes these symptoms come and go without a miscarriage occurring, especially if fetal heartbeat is detected. Yet they are always symptoms that suggest a pregnancy at risk.

Doctors may prescribe bed rest for a woman who is at risk for a miscarriage, but if spontaneous abortion is already in progress, they will analyze the woman to see if the miscarriage has completely occurred. If not, doctors may recommend a dilation and curettage (D & C) to remove placenta and the fetus from the uterus. Sometimes when fetal death occurs, this may be necessary because spontaneous abortion hasn’t occurred, which is called a missed miscarriage. Generally D & Cs are considered to prevent infection and end miscarriage discomfort, which can be significant.

Miscarriage, especially in recognized and desired pregnancies may fuel depression, and this is not entirely because of the loss of a child. Women who have had a miscarriage are at as great a risk for postpartum depression as are women who have carried a child to term. Those who desired a child may be even more at risk because they are in grief in addition to suffering the decline of pregnancy hormones. Women should report symptoms of depression to doctors, as occasionally treatment with antidepressants may be helpful or necessary.