Abortion Complications

Updated: Jan 25, 2022
  • Author: Slava V Gaufberg, MD; Chief Editor: Jeter (Jay) Pritchard Taylor, III, MD  more...
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Complications of spontaneous miscarriages and therapeutic abortions include the following:

  • Complications of anesthesia

  • Postabortion triad (ie, pain, bleeding, low-grade fever)

  • Hematometra

  • Retained products of conception

  • Uterine perforation

  • Bowel and bladder injury

  • Failed abortion

  • Septic abortion

  • Cervical shock

  • Cervical laceration

The term "septic abortion" refers to a spontaneous miscarriage or therapeutic/artificial abortion complicated by a pelvic infection.



Postabortion complications develop as a result of 3 major mechanisms as follows: incomplete evacuation of the uterus and uterine atony, which leads to hemorrhagic complications; infection; and injury due to instruments used during the procedure.

In septic abortion, infection usually begins as endometritis and involves the endometrium and any retained products of conception. If not treated, the infection may spread further into the myometrium and parametrium. Parametritis may progress into peritonitis. The patient may develop bacteremia and sepsis at any stage of septic abortion. Pelvic inflammatory disease (PID) is the most common complication of septic abortion.



Two major factors contribute to the development of septic abortion: retained products of conception and infection introduced into the uterus.

Retained products of conception due to incomplete spontaneous miscarriage or therapeutic abortion

Introduction of infection into the uterus: Pathogens causing septic abortion usually are mixed and derived from normal vaginal flora and sexually transmitted bacteria. These organisms include the following:

  • Escherichia coli and other aerobic, enteric, gram-negative rods

  • Group B beta-hemolytic streptococci [1]

  • Staphylococcal organisms [2]

  • Bacteroides species

  • Neisseria gonorrhoeae

  • Chlamydia trachomatis

  • Clostridium perfringens

  • Mycoplasma hominis

  • Haemophilus influenzae



United States statistics

Frequency of complications depends on gestational age (GA) at the time of miscarriage or abortion and method of abortion (see the Gestational Age from Estimated Date of Delivery calculator). Complication rates according to gestational age at the time of abortion are as follows:

  • 8 weeks and under - Less than 1%

  • 8-12 weeks - 1.5-2%

  • 12-13 weeks - 3-6%

  • Second trimester - Up to 50%, possibly higher

A study that estimated the abortion complication rate on a total of 54,911 abortions, including those diagnosed or treated at emergency departments, found that abortion complication rates are comparable to previously published rates even when ED visits are included. The abortion complication rate for all healthcare sources came to 2.1% (n = 1156) for medication abortion, 1.3% (n = 438) for first-trimester aspiration abortion, and 1.5% (n = 130) for second-trimester or later abortions. [3, 4]


Medical/Legal Pitfalls

Do not underestimate the amount and rate of bleeding. In the supine position, more than 500 mL of blood may collect in the vagina without severe external bleeding. Always perform a pelvic examination on a postabortion patient who is bleeding.

Failure to aggressively treat vaginal bleeding, even if it seems minimal: Stabilize the patient with 2 large-bore IVs and with oxygen. Closely monitor vital signs.

Failure to diagnose uterine perforation may lead to life-threatening complications: In postabortion patients with abdominal pain beyond the pelvic area, suspect perforation and evaluate with kidney, ureter, and bladder (KUB)/upright radiographs, pelvic ultrasonography, or CT. Consult a gynecologist and, if suspicion is high, insist on laparoscopy.

Failure to diagnose ectopic pregnancy: The chance of a missed ectopic pregnancy always exists. Do not presume intrauterine pregnancy in a patient who has just had an abortion; she may have had a missed ectopic pregnancy.

Failure to promptly administer broad-spectrum antibiotic therapy may result in complications, including sepsis and septic shock. Do not delay administration of antibiotics if a patient has signs of severe postabortion infection. Administer broad-spectrum antibiotics before completing a diagnostic workup. [5]

Failure to obtain information about recent termination of pregnancy may lead to a wrong diagnosis or delayed/inappropriate treatment.

Failure to evacuate retained products of conception from the uterus leads to treatment failure and possible complications.

Failure to diagnose bowel injury may lead to life-threatening complications.




Mortality and morbidity depend on gestational age at the time of miscarriage or abortion. [6]  In the United States, mortality rates per 100,000 abortions are as follows: fewer than 8 weeks, 0.5%; 11-12 weeks, 2.2%; 16-20 weeks, 14%; and more than 21 weeks, 18%. [7, 8]

Septic abortion remains a primary cause of maternal mortality in the developing world, mostly as a result of illegal abortions. Unsafe abortions account for nearly one half of abortions, [9]  and morbidity/mortality occurs particularly often women who live in developing nations. [10, 11, 12, 13]

According to the World Health Organization, about 68,000 women die each year due to complications from unsafe abortions, with sepsis as the main cause of death. [14]  In the United States in 2010 (the most recent year for which data were available), 10 women reportedly died from complications of legal induced abortion. [15]  There were no reports of deaths associated with known illegally induced abortions; however, this may be due to reporting issues.

In the United States, mortality from septic abortion rapidly declined after legalization of abortion. Death now occurs in less than 1 per 100,000 abortions. Figures for most European countries are similar to US rates.

The risk of death from septic abortion rises with the progression of gestation.


Other problems to be considered include the following:

  • Perforated viscus
  • Acute peritonitis

Complications of septic abortion may include the following:


Patient Education

For patient education resources, see Pregnancy Center, as well as MiscarriageAbortion, and Dilation and Curettage (D&C).