Threatened Abortion

Any pregnancy complicated by any form of bleeding from the uterus during the first 20 weeks of pregnancy is considered a “threatened abortion.”

embryo abortion
Embryo at approximately 8 weeks from conception, 10 weeks estimated gestational age from LMP.
Author: lunar caustic
CC BY-SA 2.0

The bleeding may be heavy or light, spotting or just brown discharge. It may or may not be accompanied by uterine cramping. If pregnancy tissue is passed, it is reclassified as either an incomplete or complete abortion. Inevitable abortion means the cervix has begun to dilate and bleeding is so heavy that spontaneous abortion must occur.

About 1 in every 3 or 4 pregnancies demonstrates some evidence of bleeding. The majority of these women will continue the pregnancy uneventfully and the remainder will ultimately abort.

Bedrest will usually slow the bleeding temporarily, but will not change the final outcome of the pregnancy.

Incomplete Abortion

When some pregnancy tissue has been passed, but more remains inside the uterus, this is an “incomplete abortion.”

These patients have moderate to heavy bleeding, uterine cramping, uterine tenderness and sometimes low-grade fever.

amniotic sac abortion
Author: suparna sinha
CC BY-SA 2.0

If tissue is seen protruding through the cervix, you may grasp is gently with sponge forceps and ease it the rest of the way out of the cervix. The goal of treatment is to convert the “Incomplete Abortion” to a “Complete Abortion”.

Definitive treatment is D&C (dilatation and curettage). If D&C is not available, bedrest and oxytocin, 20 units (1 amp) in 1 Liter of any crystalloid IV fluid at 125 cc/hour may help the uterus contract and expel the remainder of the pregnancy tissue, converting the incomplete abortion to a complete abortion.

Alternatively, ergonovine 0.2 mg P.O. or IM three times daily for a few days may be effective.

If fever is present, broad-spectrum antibiotics are wise, particularly if D&C is not imminent. Rh negative women should ideally receive Rhogam (Rh immune globulin) within 3 days of a completed miscarriage to prevent Rh sensitization, but it may still be effective even 7-10 days later.

If hemorrhage is present, bedrest, IV fluids, oxygen, and blood transfusion may all be necessary.

Complete Abortion

A complete abortion is the passage of all pregnancy tissue from inside the uterus.

Typically, these patients complain of vaginal bleeding and cramping which leads to passage of tissue. Then, the bleeding and pain subside.

It is sometimes difficult to know whether the abortion is “complete” or “incomplete.” To resolve this issue, some gynecologists recommend D&C for all patients who miscarry, while others recommend D&C only for those who obviously have an incomplete abortion, and those who continue to bleed and cramp.

Bedrest for a day or two may be all that is necessary to treat a complete abortion. Ergonovine 0.2 mg PO TID may be given for two days to stimulate the uterus to contract and reduce bleeding. Some physicians give a broad-spectrum oral antibiotic for a few days to protect against infection. If fever is present, IV broad-spectrum antibiotics are wise, to cover the possibility that the complication of sepsis has developed. If the fever is high and the uterus tender, septic abortion is probably present and you should make preparations for D&C.

Save in formalin any tissue which the patient has passed for pathology examination.

Continuing hemorrhage suggests an “incomplete abortion” rather than a “complete abortion” and your treatment should be reconsidered.

Inevitable Abortion

An early pregnancy which is destined to miscarry or abort is known as an inevitable abortion.

These pregnancies are complicated by bleeding and cramping and dilation (opening) of the cervix at the internal os. Such a pregnancy will not survive and can be considered in the same category as an incomplete abortion. Unless hemorrhage is present, patients can safely wait up to six weeks for definitive treatment (D&C).

Septic Abortion

Infection may complicate any abortion. Such infections are characterized by fever, chills, uterine tenderness and occasionally, peritonitis. The responsible bacteria are usually a mixed group of streptococci, coliforms and anaerobic organisms.

Usual treatment consists of bedrest, IV antibiotics, uterotonic agents (such as ergotamine or pitocin), and complete evacuation of the uterus. If the patient does not respond to these simple measures and is deteriorating, surgical removal of the uterus, fallopian tubes and ovaries may be life-saving.

If your patient responds well and quickly to IV antibiotics and bedrest, you may safely continue your treatment. Remember that the patient has the potential for becoming extremely ill very quickly and transfer to a definitive care facility should be considered.

Evacuation of the uterus can be initiated with oxytocin, 20 units (1 amp) in 1 Liter of any crystalloid IV fluid at 125 cc/hour or ergonovine 0.2 mg P.O. or IM three times daily. If the patient response is not favorable, D&C is the next step.

IV antibiotics should be started immediately. Reasonable antibiotic choices include:

Clindamycin 900 mg IV every 8 hours, plus

Gentamicin 2.0 mg/kg IV, followed by 1.5 mg/kg every 8 hours,


Metronidazole 500 mg IV every 6-8 hours, plus Gentamicin 2.0 mg/kg IV, followed by 1.5 mg/kg every 8 hours,


Cefoxitin 2.0 gm IV every 6 hours

Second Trimester Abortion

Middle trimester abortions are uncommon and usually uncomplicated. They typically involve a labor-type experience for the patient, with delivery of a nonviable fetus.

After delivery of the placenta, cramping and bleeding usually stop or reduce to a minimal amount. Pitocin, 10 units IM or 20 units in 1 L of crystalloid at 125 cc/hr are helpful in reducing postpartum blood loss.

Pitocin at reduced dosage (same IV mixture, but at 2-10 drops/minute) can be useful in stimulating the uterus to contract in the case of a retained placenta, but has the potential of overstimulating the uterus.

If the placenta remains inside longer than 6 hours, D&C is indicated to remove it. This surgery is among the more dangerous types of procedures because of the relatively large amounts of placental tissue left inside and the extreme softness of the uterus which lends itself to perforation and injury.

In the presence of vaginal hemorrhage, D&C is indicated immediately, although you might attempt a manual removal of the placenta.

If D&C fails and hemorrhage continues, hysterectomy may be life-saving.

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