An Overview of Abortion

• This is the typical case of a patient undergoing an “Accident of Pregnancy”.
  • Presents with irregular, light bleeding with some pain
  • Bimanual exam detects a soft uterus as is the case in pregnancy
    • Contrast with adenomyosis where the uterus feels spongy

• Abortion
  • Two definitions:
    • Lay Definition – termination of pregnancy for whatever reason
    • Medical Definition – unexpected end to pregnancy before 20 weeks gestation
      • “miscarriage” in lay terms
        • When telling a patient they are having a spontaneous abortion you are advised to translate to lay language to avoid any misunderstanding.
  • 15% of all clinically recognized pregnancies will end in abortion
  • 80% of all “chemical pregnancies” (those with positive pregnancy tests) end in abortion
     

Types of Spontaneous Abortion

• Threatened – abnormal bleeding early in pregnant woman who continues to maintain a live intrauterine pregnancy
  • 20% of women experience some bleeding (spotting) within the first and early part of their 2^nd trimester most is considered to be due to implantation bleeding
  • Implantation occurs about 7 days after fertilization and commonly
  • 50% of threatened go on to be normal pregnancies and there is no way to tell which direction the patient will go
  • Cervix is closed and the uterus is appropriately sized and soft

• Complete – pain and bleeding and passed all products of conception
  • Cervix is closed and the uterus is small and firm
• Inevitable – pain (abdomen and back), bleeding but has not passed any tissue
  • Cervix is open allowing a finger usually you can palpate the uterus
  • This person will have an abortion before 20 weeks gestation!
  • There have been recent deaths in New Jersey from rupture of membranes à vaginal bleeding who got septic
• Incomplete – cramping and pain with vaginal bleeding with variable flow which contains some products of conception
  • Cervix is open and the uterus has retained some products of conception
  • We worry most about these patients
    • They usually bleed very heavily before 7-8 weeks gestation they will pass everything at once
    • Between 7-10 weeks they will pass the gestational sac with placental remnants in the uterus and will continue to bleed until the uterus is completely evacuated
• Missed – embryo has either failed to form or has expired but there hasn’t been any passage of tissue and the patient will complain of abdominal pain and vaginal bleeding
  • Cervix is closed and an irregular gestational sac with no fetal pole is seen on ultrasound.
  • This is what the lady in this case had
• Moles
  • Considered “accident in pregnancy” but not discussed in this context because though they present with symptom of abnormal bleeding the way we deal with them is different
     

• Etiology
  • Maternal Factors:
    • Infectious
      • All STD’s
      • Fetuses have been found to culture these organisms but no causal relationship has ever been established and it will never be known due to the unethical study that it would require
    • Environmental exposures
      • Referring to intrauterine environment
        • Smoking increases the risk in a linear fashion
        • Alcohol in a dose dependent response
        • Radiation can cause different effects at different gestational ages
          • Early (1^st 2-4 weeks) usually is fatal at high enough dose à “all or nothing effect” = either has no effect or causes abortion
          • Studies based on atomic bombs the radiation dose we start to worry about is 5 RAD where we start seeing developmental effects
            • Any radiological procedure (below 5RAD) is safe during pregnancy except for fluoroscopy which still is used when absolutely required
            • 100 RAD is the lethal dose of radiation
        •   Caffeine intake greater than 300 mg/day about 5-6 cups of coffee which is close to what you order at Starbuck’s
    • Systemic disorders
      • Hypothyroidism
      • Poorly controlled diabetes and HTN
      • Lupus and Autoimmune Disease
        • Women positive for anti-cardiolypin and IgG, IgM lupus anti-coagulant have a 75% chance of having a subsequent abortion if they have had one previously à they are known as “habitual aborters”
      • Thrombophilias
        • Cause 2^nd and 3^rd trimester losses due to vascular compromise
        • Microinfarcts in the placenta give a clue to underlying thrombophilia as the cause of a still birth
    • Uterine abnormalities à submucosal myomas don’t need to be that big the intramural myomas tend to need to be bigger
      • Acquired
        • Congenital uterine defects
          • Cause miscarriages due to poor implantation
      • Developmental
  • Fetal Factors:
    • Aneuploidy- the overwhelming reason for first trimester abortion!!!
      • Any kind can cause a miscarriage
      • MOST COMMON TYPE OF ANEUPLOIDY THAT CAUSES MISCARRIAGE
        • Autosomal Trisomies as a group
      • MOST COMMON SINGLE ANEUPLOIDY THAT CAUSES MISCARRIAGE
        • Monosomy X (Turner Syndrome)
          • Accounts for 20% of all aneuploidy caused miscarriages
             
• Symptoms
  • Vaginal bleeding
  • Pelvic pain or cramping
  • Passage of products of conception
    • This will guide your diagnosis
       
• Diagnosis
  • History
  • Physical Exam
  • Pregnancy Testing
    • Qualitative – make sure patient is pregnant à Yes or No
    • Quantitative – look at individual beta-HCGs
      • We look at this because it’s difficult to figure out what’s happening with the patient because you only see them in a moment in time.
  • Ultrasonography
    • The most important adjunct test!
    • Remember that you should be able to see the yolk sac
    • Examples were shown in class
      • Baby has a heart beat, enlarged uterus, vaginal bleeding and pain with a closed cervix à Threatened abortion
      • Gestational sac is irregular: not round and nothing inside, vaginal bleeding and the cervix is closed, would still be read as a positive pregnancy  à Missed abortion
      • Cervix is closed, bleeding and cramping are present, no gestational sac à Complete (nothing in uterus at all à thin)
        • Beta HCGs would be very helpful because we need to know for ultrasound what the threshold is that we’ll be able to see anything à discriminatory zone
          • The discriminatory zone is the level of hCG beyond which an intrauterine pregnancy is consistently visible
            • 1500-2000 beta HCG for most hospitals
          • need to ask radiologists at what beta they’ll be able to see an intrauterine gestation
          • if a beta HCG comes back as 800 we need to reevaluate a diagnosis of incomplete à might have a gestation that just can’t be seen yet, the patient needs to come back after another 48 hours to redo ultrasound
      • irregular gestational sac with a little embryo sitting at the bottom (not “floating”), no fetal heart beat, cervix is closed, bleeding and cramping is present à Missed abortion
         
• Treatment of Abortion
  • Observation – just watch the patient
    • Inevitables will complete can help by evacuating the uterus
    • Don’t intervene in case of threatened abortion unless its an undesired pregnancy
    • Missed abortions will eventually pass the pregnancy
  • Surgical evacuation of uterus
    • DNC – up to 12-14 weeks
    • DNE – after that gestational point
      • These two procedures differ in their approach which we’ll learn about next year
  • Remember to check Rh status of the patient
    • Once you have an established fetus with their own blood supply there can be isoimmunization even after 1^st trimester losses, if the mother is Rh –ve they need to receive Rh immunoglobulin    
• Clinical Presentation of the different types of abortion
  • Classic Complete:
    • Patient comes in with cramping and light bleedingà the cramping will get worse and the bleeding will get very heavyà they’ll pass what feels like a large clot à the pain quickly (within a few hours) gets much better and the bleeding decreases and continues for a week or so
  • Missed:
    • Constant light bleeding with a little cramping à no passage of tissue
  • Incomplete:
    • Light cramping and bleeding that worsens to heavy cramping and bleeding à pass what they believe is a little tissue but they continue to bleed and cramp
  • Inevitable
    • Diagnosis made upon physical exam, patient presents with some light bleeding and cramping

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