3. TEACHING POINTS: EVALUATION BEFORE UTERINE ASPIRATION

EXERCISE 3.1

Purpose: To distinguish appropriate uses for different types of pregnancy tests. For the following scenarios, indicate whether you would use a high sensitivity urine pregnancy test (HSPT) or a serum quantitative hCG test, the reasons why. Address related questions.

  1. A patient comes to your office requesting pregnancy confirmation and to discuss her options. She is 4 weeks 2 days LMP.
    • A HSPT is the most useful test to confirm an early pregnancy, both for home and office-based confirmation of pregnancy.
    • The modern HSPT can detect levels as low as 20 mIU/ml. These levels may be seen in urine as early as a week after conception or before a missed period (although 95% sensitivity may not be reached until cycle day 32-35). Up to 10% of pregnancies have a negative HSPT at the time of missed menses, due often to delayed ovulation & implantation and to variable hCG concentrations in urine (Paul 2009; p.67); furthermore there is variable sensitivity among HSPT assays.
    • If positive, assess if pregnancy is desired, and proceed with clinical dating.
      If negative, patient should retest in a week if menses does not start.
  2. A patient is 6 weeks by LMP with a pregnancy of unknown location (transvaginal ultrasound examination shows no intrauterine gestational sac and no ectopic pregnancy). The patient has been spotting intermittently but is otherwise asymptomatic. The quantitative hCG you draw comes back at 1000, and another 48 hours later comes back at 1400.
    1. What is the differential diagnosis?
      • The patient’s hCG rise is <53% in 48 hours.  Early pregnancy loss or ectopic are most likely, but early viable pregnancy is also a possibility.
    2. Would your approach to care differ with a desired vs undesired pregnancy?
      • Although a rise of hCG level <53% over 48 hours rules out IUP 99% of the time, a lower cutoff of <35% rise rules out IUP 99.9% of the time (Morse 2012), and this stricter criterion of <35% can be considered in a desired pregnancy, instead of <53% (See Chapter 8 PUL algorithm).  A third hCG measurement on day 4 can help clarify the diagnosis for PUL (Zee 2014).
      • If the pregnancy is undesired, an immediate diagnostic uterine aspiration will expedite the evaluation for possible ectopic pregnancy.  If pregnancy tissue is found in the aspirate, an ectopic pregnancy can be ruled out.  In the more likely case that pregnancy tissue is not found, a repeat hCG level 24-48 hours after the aspiration will be helpful.  If the gestational sac was aspirated, the hCG level will drop by more than 50%.  If the patient is symptomatic or the hCG does not drop by 50%, an ectopic pregnancy becomes more likely, and an immediate high level TVUS is warranted.  Return to Exercises
  3. A patient returns for a follow-up visit 3 weeks after a first trimester aspiration because of intermittent bleeding since. The patient started taking oral contraceptive pills the day following the aspiration and have been sexually active since the uterine aspiration.
    • The HSPT can stay positive for 4 to 6 weeks following an abortion. Only a negative HSPT test is helpful in that window.
    • Take history for other signs of pregnancy. Keep in mind that breast tenderness may be a consequence of starting estrogen-containing oral contraceptives.
    • Consider checking the procedure record to check that aspiration was complete and appropriate POC (products of conception) were noted.
    • If there are ongoing symptoms or signs of pregnancy or retained POC, check serial hCGs to assess trend. Repeat US can also be helpful.

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EXERCISE 3.2

Purpose: To review key information about ultrasound in early pregnancy.

  1. What is the differential diagnosis of the following ultrasound findings? What steps would you take to clarify the diagnosis?
    1. Mean gestational sac diameter 18 mm with no yolk sac or embryo visible.
      • A mean sac diameter of 16-24 mm with no yolk sac or embryo is highly suggestive of a non-viable pregnancy, while a mean sac diameter of ≥25 mm without an embryo is diagnostic of early pregnancy loss (anembryonic pregnancy).
      • If a pregnancy is undesired, there is no reason to delay uterine aspiration to wait for diagnosis; and a diagnostic aspiration will assist in the evaluation of a possible ectopic pregnancy.
      • If a pregnancy is desired, recheck US in 7-10 days.
  2. Embryonic pole length 5 mm with no visible cardiac activity.
    • Early pregnancy loss is highly suggested by lack of embryonic cardiac activity in a 5-7 mm embryonic pole, and diagnostic > 7 mm embryonic pole.
    • If a pregnancy is undesired, avoid delaying uterine aspiration / management.
    • If the pregnancy is desired, repeat US in 7 – 10 days.
  3. A 3 mm x 3 mm central anechoic fluid collection in pregnant patient 5w3d by LMP with history of intermittent right lower quadrant cramping.
    • This case indicates likely ectopic pregnancy. By 5 3/7 weeks, or 38 days, the mean sac diameter should be 8 mm. A normal sac should also be eccentrically placed and not centrally located in the uterine cavity. Combined with the cramping pain in the right lower quadrant, findings consistent with a pseudosac should make you think of ectopic pregnancy. Refer for workup.
  4. Embryonic pole length 8 mm with no visible cardiac activity
    • Embryonic pole length > 7 mm is diagnostic for early pregnancy loss (Doubilet 2013). Management options including aspiration, medication, or expectant management. See Chapter 8 for more on EPL counseling and management.
  5. Irregular, flattened gestational sac without embryo, with cystic changes present resembling “swiss cheese” pattern in patient who is 8 weeks LMP.
    • This suggests molar pregnancy, which may appear with heterogeneous or mixed-density echoes resembling early pregnancy loss on ultrasound. The classic moth-eaten, “swiss cheese”, or what was described as “snowstorm” appearance of molar pregnancy on ultrasound often is not visible until after 10 weeks gestation.
    • Patients with molar pregnancy are at increased risk for bleeding. Some clinicians will refer for inpatient management after 12 weeks.
    • If performing aspiration, send tissue for pathologic examination, and obtain baseline serum hCG.
    • Can monitor hCGs according to established protocols (such as ACOG 2004) or refer for further management.

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EXERCISE 3.3

Purpose: To identify pre-procedure conditions that may warrant special management. Consider how would you manage the following case scenarios. Not all material is covered in the Chapter.

  1. A 41-year-old patient presents for aspiration at 5 weeks LMP. Pelvic examination reveals an irregular uterus that is 17 weeks in size. Ultrasound examination shows an intrauterine sac in the fundus consistent with 5 weeks gestation and multiple submucosal uterine fibroids.
    • Uterine fibroids may inhibit our ability to complete the procedure, and medication aspiration is an excellent alternative to aspiration.
    • Consider checking hemoglobin, as patients with significant fibroids can be anemic, and also may bleed more than others during MAB & aspiration.
    • Use ultrasound to identify sac location in relation to the fibroids. If a small 5-week sac is high in the fundus “behind” the curve of large or multiple fibroids, it may be very difficult to reach. Refer beyond the outpatient setting with an experienced provider.
    • Ultrasound guidance may be a helpful adjunct to any procedure with fibroids.
  1. A 26-year-old patient presents to your office at 7 weeks gestation. They had a chest x-ray and abdominal series after a motor vehicle accident 2 weeks ago and decided to have an abortion because of concerns about the effects of the radiation on the fetus.
    • Many patients overestimate the harmful effects of exposures. While this may be a conscious or unconscious way to justify a pregnancy termination, it is so useful to point this out. But it is our responsibility to give accurate information for informed choices.
    • A cumulative fetal radiation exposure should be limited to less than 5 rad (radiation absorbed dose). (ACOG 2016, ACR 2014)
    • Although fetal exposure to ionizing radiation is linked to malformations, the exposure of most plain-film radiographs is far below the harmful threshold.
      Chest x-ray (2 view) 0.00007 rad
      Abdominal x-ray (1 view) 0.1 rad
      IVP ≤ 1 rad
      CT of head or chest ≤ 1 rad
      CT of abdomen or LS spine 3.5 rad
    • MRI: Although there have been no documented adverse fetal effects, its use is advised against in the first trimester (National Radiological Protection Board).
  2. You are preparing to perform a uterine aspiration on a patient who is 5 weeks pregnant. When you insert the speculum, you note that the cervix looks inflamed and friable and has pus at the os.
    • CT / GC testing and treatment is indicated, as cervical infection with these pathogens greatly increases risk of post-abortal endometritis.
    • Pre-treatment prior to the procedure is indicated (Achilles 2011). Most providers delay the aspiration until at least one dose of antibiotic is given pre-procedure. No randomized trials have compared no delay / pre-aspiration treatment with delay/post-abortion treatment (Paul 2009; p.82).
    • CDC 2015 Guidelines for treatment of cervicitis include:
      • Chlamydia: Azithromycin 1 gm single oral dose OR Doxycycline 100 mg orally twice daily for 7 days are the recommended regimens.
      • Gonorrhea: Ceftriaxone 250 mg intramuscular PLUS treatment for Chlamydia.
    • Symptomatic BV at the time of aspiration should be treated with metronidazole 500 mg orally twice daily for 7 days. There is no need to delay the abortion to complete treatment. There is insufficient data to recommend that treatment for asymptomatic BV is superior to routine pre-procedure antibiotic prophylaxis (Achilles 2011).
  3. 40-year-old G4P3 patient at 7w4d presents for termination with a BMI of 35 and a history of three previous cesareans.
    • The patient’s age, obesity and previous cesarean sections put this patient in the moderate risk category for hemorrhage (Kerns 2013) in addition to a difficult uterine aspiration. In addition to what you would do for a low risk patient (see Chapter 5 Managing Complications Table), the following should also be considered:
      • Have uterotonic medications and Foley balloon readily accessible.
      • If not routinely used, add vasopressin or epinephrine to paracervical block
      • Consider intraoperative ultrasound guidance.
      • With additional risk factors, consider referring out to center with transfusion capability, anesthesia, and / or interventional radiology.
  4. A 29-year-old patient presents for aspiration at 7 weeks gestation. They have a prior history of venous thromboembolism and are currently anti-coagulated on warfarin; the INR is in the therapeutic range.
    • Additional blood loss in anti-coagulated patients was not clinically significant in a recent small study of anti-coagulated patients seeking aspiration < 12 weeks gestation compared with matched controls (Kaneshiro 2011). A likely explanation is that myometrial contraction is the primary mechanism of hemostasis after uterine aspiration.
    • Cases such as this can be done in the outpatient setting with appropriate preparation for unlikely bleeding. Some providers will ask the patient to hold the morning dose of low- warfarin or molecular-weight heparin although the benefit of this is unclear. Return to Exercises
  5. A 38-year-old patient presents for an aspiration at 6 weeks gestation, with a blood pressure is 170/110 and a headache.
    • Mild to moderate hypertension is not a contraindication for an outpatient procedure, but requires subsequent referral for treatment of hypertension.
    • Confirm the blood pressure with adequate cuff size; check if patient is on anti-hypertensive medication and if they took it today. Consider allowing patient to take their anti-hypertensive medication if they have it, or relax for a while and recheck. Sedation will also reduce the blood pressure.
    • For severe hypertension (i.e. >160/110) who is symptomatic – with new onset headache or neurologic changes and pressures concerning for malignant hypertension.  The patient should be treated prior to the procedure (beta-blocker or vasodilator) or referred for additional management.
  6. A 26-year-old patient with a history of diabetes presents for an aspiration at 8 weeks gestation. A pre-operative glucose level is 520 mg/dL.
    • Take patient history for diabetic control medications and whether taken today, trends, A1c, typical levels, history of emergency care.
    • Mild hyperglycemia (200-400 mg/dL) is not a contraindication for uterine aspiration, but an assessment is appropriate above this range to determine if the patient has ketoacidosis (including urine dip for ketones and evaluation of volume status); in which case they should be stabilized or referred prior to the procedure.
    • Hypoglycemia (<70 mg/dL) warrants a patient to be fed or stabilized prior to a procedure.

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