Autopsy of pregnant mother

Most deaths associated with pregnancy are not related to medico-legal investigations, these include deaths due to complications of childbirth, pre-existing medical conditions of mother and medical termination of pregnancy.  Furthermore, an estimated 26 million legal and 20 million illegal abortions are performed annually across the globe.

For better understanding of the cause of death in deaths associated with pregnancy, complete postmortem examination should be carried out, including histological and other essential ancillary investigation.

The most common direct causes of maternal deaths include:

  • Thrombosis and thromboembolism
  • Hypertensive disease of pregnancy
  • Amniotic fluid embolism
  • Early pregnancy death
  • Sepsis
  • Hemorrhage
  • Genital tract Trauma
  • Anesthesia related complication

Although, medical termination of pregnancy is legalized in our country, illegal abortions are still being carried out by both trained and untrained medical personnel. Legal abortions has very low maternal mortality as they are carried out in well-equipped facilities and performed by well-trained medical persons.

The usual methods include vacuum aspiration, dilatation and curettage and medically induced termination of pregnancy. Risk of death is still present, even when carried out in a fully functional setup, by well-trained personnel. The common causes of death for such scenarios include:

  • Pulmonary embolism from leg vein thrombosis
  • Anesthetic Mishap
  • DIC and Cerebral damage when abortion was induced by intra-chorionic injection of hypertonic saline or glucose
  • Air embolism following vacuum aspiration though rare
  • When treatment failed in response to excessive bleeding and infection.

Death following illegal abortion
When abortion is carried out by a doctor with aseptic and anti-septic precautions, with full antibiotic coverage, the chance of risk is minimal, as compared to the rough technique applied by an unskilled person using improvised instruments. The most common methods for illegal abortion are as follows:

The gestational sac is damaged by dilatation of cervical canal, using all kinds of instruments from surgical dilators to wooden cylindrical sticks. When abortion is performed by a doctor or paramedic, using sterile instruments, the risk of complications is minimal. On the other hand, when performed by a quack, use of extreme force may lead to perforation of the vault of vagina or fundus of uterus, even damaging coils of intestine or liver. The external os may be injured by repeated blind attempts to introduce thick objects into the undilated cervical canal. Perforation of vaginal wall and uterine cavity may lead to excessive bleeding and sepsis from generalized peritonitis. Another risk of instrumentation is cervical shock when dilatation is performed without anesthesia.

Air insufflation
Abortion is carried out by introducing fluid, under pressure, into the uterine cavity, with the help of a rubber pump or enema syringe. This causes separation of chorionic sac from the wall of the uterus, exposing the placental bed. Complete separation of the sac results in abortion.

Apart from the dangers of bleeding and infection, this procedure carries the increased risk of air embolism. When empty syringe with air is pushed into a uterus having exposed vascular channels, air can enter the venous sinus and pelvic veins and cause embolism.

Physical violence
Pregnant women may suffer violent acts from husband or consorts such as punching and kicking of abdomen, to induce abortion. This may result in rupture of liver, spleen or intestine, ensuing death from complications.

Syringe aspiration
Syringing is safer, when compared with other methods of abortion, so long as aseptic precautions are undertaken. If product of conception are retained, they can acts as a source of infection and can lead to death.

Autopsy technique, in cases of maternal death, does not require significant deviation from a standard postmortem examination. Of course, special attention should be given to known causes of maternal death. In developing countries like Nepal, the cause of death associated with abortion is much more likely to be associated with infection and uncontrolled bleeding. In any case, doctor must use appropriate autopsy techniques and ancillary investigations.

Circumstances of death and detailed medical history should be obtained before starting the autopsy. If death occurred in hospital, it is always advisable to communicate with the treating doctor(s) and obtain medical records. This may help during postmortem examination by helping focus examination as well as for collection of samples for ancillary investigations.

In case of criminal abortion, a careful examination must be carried out as follows:

  • In case of clostridial infection and liver damage, skin may appear bronze in color.
    Abdominal distention and breast changes should be assessed for estimation of duration of pregnancy.
  • In genital examination, signs of recent or current pregnancy and attempted or successful recent abortion(s) should be noted. Vaginal bleeding and injuries like abrasions, contusions and lacerations may be present over vulva, resulting from instrumentation.
  • Any fluid present over the genitalia should be collection for chemical analysis. Swabs should be taken for microbiological culture.
  • When pneumothorax or air embolism is suspected, X-ray of chest and abdomen should be taken before evisceration; if x-ray is not possible then it must be sought during dissection. Air embolism can be detected by visualizing air bubbles in the heart chambers, great veins and inferior vena cava, peritoneal cavity and pelvic veins.
  • The main pulmonary artery should be dissected to check for thromboembolism. Lanugo, vernix or meconium may be seen, indicating amniotic fluid emboli.
  • En-bloc removal of perineum and internal genitalia should be routinely performed

Examination of female pelvic organs by en-bloc resection
The dissector must carefully examine the pelvic organs in cases of suspected criminal abortion and document all vaginal, cervical and uterine injuries. Since, these areas lies deep within the pelvis, complete external examination is often inadequate. Pelvic organs need to be examined following en-bloc removal, which allows for a complete inspection while maintaining the natural positions.

After completion of abdominal evisceration, a diamond-shaped incision is given over the skin enclosing the vulva and anus. The incision should penetrate into the deep soft tissue, and is bounded laterally by ischio-pubic rami, anteriorly by the pubic symphysis, and posteriorly by the coccyx. The internal incision is given along the pelvic inlet, enclosing the pelvic organs. The rectum and adjacent soft tissues are dissected away from the sacrum and urinary bladder is dissected away from the pubis.

Once the internal and external incision joins within the pelvis, the vulva, ureter, urinary bladder, vagina, uterus, fallopian tubes, ovaries, anus and rectum are removed as a single bloc. This tissue bloc can be removed superiorly from pelvic inlet or antero-inferiorly from ischio-pubic rami.

The tissue bloc is thoroughly examined by placing over the cutting board. The anus and rectum is opened with long scissors along the posterior aspect and mucosa inspected for any lesions or injuries after washing with water. The vaginal wall may be opened along the anterior or posterior wall depending upon the presence of injuries. This allows for examination of vaginal mucosa, external Os and junction of vulva and vagina. The urinary bladder, uterus, fallopian tubes and ovaries are examined using the usual procedure.