Early Pregnancy Loss Clinical Presentation

Patients with spontaneous complete abortion usually present with a history of vaginal bleeding, abdominal pain, and passage of tissue. After the tissue passes, the vaginal bleeding and abdominal pain subsides.

• Vaginal bleeding is usually heavy.

  • Quantification of the amount of bleeding is very important because life-threatening hemorrhage may occur. The patient may be able to quantify the number of pads or tampons used over a specified time and qualify the amount that each pad is soaked. This is just an estimate; yet, soaking a pad or more an hour suggests significant and worrisome amounts of bleeding that require prompt attention. These patients should be sent to the emergency department.
  • The presence of blood clots suggests heavy bleeding. The presence of blood clots also may be confused with passage of tissue.
  • Examining the passed material helps clarify whether the material is clot or tissue. If the material is tissue, then the type of abortion may be identified. If the tissue is evaluated and appears complete, then a complete abortion is confirmed.
• Abdominal pain is associated with concurrent abortion and resolves with the completion of the abortion.

  • The pain usually is in the suprapubic area, but reports of pain in one or both lower quadrants are not uncommon.
  • The pain may radiate to the lower back, buttocks, genitalia, and perineum.
  • If the pain is occurring only on one side, consider an ectopic pregnancy or a ruptured ovarian cyst as possible causes.
• Consider any reproductive-aged woman presenting with vaginal bleeding to be pregnant until proven otherwise.
• Other symptoms, such as fever or chills, are more characteristic of infection, such as in a septic abortion. Septic abortions need to be treated immediately, otherwise they may be life threatening.

Patients who are pregnant and bleeding vaginally need immediate evaluation.

• Estimating the patient's hemodynamic stability is the first step.

  • Obtain orthostatic vital signs.
  • Initiate fluid resuscitation early in cases of orthostatic hypotension.
  • Abdominal and pelvic examinations are next.
• The abdominal examination helps determine whether or not the state of an acute abdomen is present.

  • In a complete abortion, the abdomen is benign, with no distension, no rebound, normal bowel sounds, no hepatosplenomegaly, and mild suprapubic tenderness.
  • Usually, the uterus is either not palpable abdominally or is just slightly above the pubic symphysis in a first-trimester pregnancy loss. The uterus can be enlarged due to other pathology (eg, leiomyomas).
  • If rebound tenderness or a distended abdomen is present, a complete abortion is unlikely. Assume instead that an ectopic pregnancy is present and if rebound tenderness is present, then provide the patient with aggressive fluid resuscitation with 2 IV lines, quantitative hCG, stat ultrasound (if stable enough) and an emergent laparoscopy or an emergent exploratory laparotomy.
• In the case of a complete abortion, pelvic examination may show some blood on the perineum or vagina but limited active bleeding.

  • Cervical motion tenderness does not exist.
  • The cervical canal is closed.
  • The uterus is smaller than expected for dates, and it is nontender to mildly tender.
  • The adnexa are nontender to mildly tender. Usually, no adnexal masses exist, unless a corpus luteum is still palpable.
  • In summary, the pelvic examination check list includes assessment of the following:
    • Source of bleeding (cervical os)
    • Intensity of bleeding (active, heavy, clots)
    • Any presence or passage of tissue
    • Cervical motion tenderness (increases suspicion for ectopic pregnancy)
    • Cervical os closed for complete or threatened abortion (If it is open, consider inevitable or incomplete abortion.)
    • Uterine size and tenderness
    • Adnexal masses (suspicious for ectopic pregnancy)

• In the first trimester, embryonic causes of spontaneous abortion are the predominant etiology and account for 80-90% of miscarriages (See following image.) Second transvaginal sonogram obtained 1 week after the initial study fails to demonstrate fetal development. This confirms the diagnosis of an embryonic pregnancy.
• One study suggests that an inflammatory reaction occurs in normal pregnancy and may be disrupted during miscarriage.^[7]
• Genetic abnormalities within the embryo (ie, chromosomal abnormalities) are the most common cause of spontaneous abortion and account for 50-65% of all miscarriages.

  • The most common single chromosomal anomaly is 45,X karyotype, with an incidence of 14.6%.
  • Trisomies are the single largest group of chromosomal anomalies and account for approximately one half of all anomalies associated with miscarriage. Trisomy 16 is the most common trisomy found.
  • Approximately 20% of genetic abnormalities are triploidies.
• Teratogenic and mutagenic factors may play a role, but quantification is difficult.
• Maternal causes of spontaneous miscarriage include the following:

  • Genetic: Maternal age is directly related to the aneuploidy risk (>30% in people aged 40 y). Couples with recurrent miscarriages have a 2-3% incidence of a parental chromosomal anomaly (ie, balanced translocation).
  • Structural abnormalities of the reproductive tract include the following:
    • Congenital uterine defects (particularly uterine septum)
    • Fibroids
    • Cervical incompetence
• Iatrogenic causes (ie, Asherman syndrome)
• Acute maternal factors include the following:

  • Corpus luteum deficiency
  • Active infection (eg, rubella virus, cytomegalovirus, Listeria infection, toxoplasmosis)
• Chronic maternal health factors include the following:

  • Polycystic ovary syndrome
  • Poorly controlled diabetes mellitus (A successful pregnancy requires much tighter control.)
  • Renal disease
  • Systemic lupus erythematosus (SLE)
  • Untreated thyroid disease: A meta-analysis evaluating the association between thyroid autoantibodies and miscarriage and preterm birth in women with normal thyroid function found a strong link between maternal thyroid autoantibodies and miscarriage and preterm birth.^[8] Evidence suggests that treatment with levothyroxine may attenuate the risks.
  • Severe hypertension
  • Antiphospholipid syndrome
• Exogenous factors include the following:

  • Tobacco
  • Alcohol
  • Cocaine
  • Caffeine (high doses)
• Independent risk factors for a spontaneous miscarriage include the following:^{[3, 4, 5]}

  • Advanced age
  • Extremes of age
  • Feeling stressed
  • Advanced paternal age
• Symptoms of vaginal bleeding but not abdominal pain are associated with increased risk of miscarriage. One paper suggests that miscarriage can occur in about 50% of patients who present with threatened abortion.
• NSAID use: Gestational exposure to nonaspirin NSAIDs may increase the risk for miscarriage. Nakhai-Pour et al identified 4705 women who had spontaneous abortions by 20 weeks’ gestation. Each case was matched to 10 control subjects (n=47,050) who did not have a spontaneous abortion. In the women who had a miscarriage, 352 (7.5%) were exposed to a nonaspirin NSAID, whereas NSAID exposure was lower (1213 exposed [2.6%]) in women who did not have a miscarriage.^[9]