Purpose: To review key steps in early pregnancy evaluation and pregnancy dating.

  1. A 25-year old G1 P0 patient calls your office for a telehealth visit about options for an undesired pregnancy, following a positive home pregnancy test.
    1. How will you determine the patient’s estimated gestational age?
      • In early pregnancy, LMP alone has been shown to be an accurate means of estimating gestational age with low rates of under- or over-estimation in abortion evaluation to mid first trimester or 63 days (Kapp 2020, Ipas 2021, Macaulay 2019, Raymond 2015, Schonberg 2014)
      • Pairing bimanual exam with LMP dating may increase the accuracy of gestational age estimation but is not required to proceed with a medication or aspiration abortion.
      • If LMP is unknown, a series of questions (Are you >10 weeks pregnant? Have you missed >2 periods? Are you >2 months pregnant?) may be used to determine eligibility for medication abortion (Ralph 2021).
      • If pregnancy dating is uncertain, or if there are any signs or symptoms of ectopic pregnancy, US may be warranted (Raymond 2020).
    2. What additional diagnostic data would you consider obtaining?
      • No labs are required unless:
      • Rh if indicated (See Chapter 3 or 5: Rh Isoimmunization)
      • Hgb or Hct only if recent history and / or symptoms of anemia
      • CT / GC if symptoms or risk factors (See Chapter 5)
      • Tests pertinent to underlying conditions if needed
        1. Glucose for patients with insulin-dependent diabetes mellitus
        2. INR for patients on certain anti-coagulants (Warfarin) > 12 weeks

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Purpose: To review appropriate uses for different types of pregnancy tests. For each scenario, indicate whether you would use clinical assessment alone, a high sensitivity urine pregnancy test (HSPT), or a serum quantitative hCG test and why; and / or answer related questions.

  1. A 20-year-old G2 P1 patient at 4 weeks 2 days by LMP comes to your office requesting pregnancy confirmation and to discuss options.
    • A HSPT is the most useful test to confirm an early pregnancy, both for home and office-based confirmation of pregnancy.
    • A 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, often due to delayed ovulation & implantation and to variable hCG concentrations in urine (Paul 2009; p.67). Furthermore, not all HSPT tests are equal; with detection hCG levels varying from 20-30 mlU/ml.
    • If positive, assess if the patient desires to continue the pregnancy, and proceed with clinical dating. If negative, patient should retest in a week if menses does not start.

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  1. A 27-year-old G3 P2 patient is 6 weeks by LMP with a pregnancy of unknown location (transvaginal US 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?
      • Research indicates that the minimum expected hCG rise for a viable IUP is 35-53% at 48 hours (Butts 2013). This patient’s hCG rise is 40% in 48 hours. The differential still includes early pregnancy loss, ectopic, and early viable pregnancy. The hCG patterns need to be combined with EGA and clinical symptoms when clinically managing patients.
    2. Would your approach to care differ if the patient desires to terminate vs continue the pregnancy?
      • According to prediction models (Morse 2012), 99.9% of viable IUPs will have a rise in hCG of at least 35% in 48 hours. However, because some viable IUPs will have a slower rise, it is important to obtain a third hCG measurement and repeat the US if the intent is to continue the pregnancy (Zee 2014).
      • If the patient desires to terminate the pregnancy, offer a diagnostic uterine aspiration, because that 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 a referral is warranted.

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  1. A 32-year-old G2 P1 patient returns for a follow-up visit 5 weeks after a first trimester aspiration because of intermittent bleeding since their procedure, and has been sexually active since the uterine aspiration.
    • The HSPT is helpful if negative, but can stay positive 4 + weeks post-abortion.
    • If there are ongoing symptoms or signs of pregnancy or retained tissue, consider serial hCGs to assess trend. Repeat US may also be helpful.

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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. A 36-year-old G4 P2 patient at 5 weeks by LMP. In the longitudinal view of the uterus, a gestational sac is elliptical, fundal and eccentric to the midline. Mean sac diameter is 18 mm with no yolk sac or embryo visible.
      • This is an intrauterine gestational sac. The mean sac diameter of 16-24 mm with no yolk sac or embryo is highly suggestive of a non-viable pregnancy in this case, although early viable pregnancy and ectopic are still in the differential. If the mean sac diameter was ≥25 mm without an embryo, it would be diagnostic of early pregnancy loss (anembryonic pregnancy).
      • Based on what the patient desires to do with the pregnancy, may use shared decision making to offer either aspiration procedure or medications. Aspiration procedure should not be delayed for diagnosis and can help confirm pregnancy location (RHAP 2017) . If patient prefers medication, can be offered with ectopic precautions and paired with serum hCG trend and close follow-up.
      • If patient desires to continue the pregnancy, diagnosis will be clarified by repeating US in 7-10 days.
    2. Embryonic pole length 8 mm with no visible cardiac activity
      • Embryonic pole length > 7 mm with no cardiac activity 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.
    3. A 24-year-old G2 P1 patient at 5 weeks and 3 days by LMP reports having intermittent right-sided pelvic pain and cramping. On ultrasound, you visualize a small 3 mm x 3 mm intrauterine fluid collection in the endometrial canal. The shape of the collection is triangular and there is no double decidual sign.
      • This case is concerning for 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 unilateral cramping pain, findings consistent with a pseudosac should prompt ectopic pregnancy workup and management.
    4. A 30-year-old G3 P0 patient reports they are 10 weeks by LMP and having intermittent spotting. On ultrasound, there is a flattened gestational sac without embryo or yolk sac, with cystic changes in the decidua present resembling “swiss cheese”.
      • This suggests molar pregnancy, which may appear with heterogeneous or mixed-density echoes on US. The classic moth-eaten, “swiss cheese” or “snowstorm” appearance on US may not be visible until 9-10 weeks EGA.
      • For suspected molar pregnancy, tissue diagnosis is needed, so uterine aspiration is recommended over medication abortion. If uterine size is over 12 weeks, refer for inpatient management due to increased bleeding risk.
      • When aspiration is performed, tissue should be sent for pathologic examination, and baseline serum hCG obtained. If molar pregnancy is confirmed, hCGs should be monitored according to established protocols (ACOG 2004).

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Purpose: To consider management of case scenarios prior to uterine aspiration. Not all material is covered in the Chapter.

  1. A 41-year-old G4 P3 patient presents for aspiration at 5 weeks LMP. Pelvic examination reveals an irregular uterus that is 17 weeks in size. Ultrasound examination shows a 5-week intrauterine gestation and multiple uterine fibroids.
    • Discuss additional considerations for aspiration vs. medication in setting of fibroids, given increased risk of incomplete aspiration procedures. A small gestational sac can occasionally be high in the fundus “behind” the curve of large or multiple fibroids, and it may be very difficult to reach
    • Consider performing the procedure under US guidance. Refer to a higher-level setting with an experienced provider if necessary.
    • Consider checking hemoglobin if symptomatic, as patients with fibroids can have anemia, and may have a higher risk of increased bleeding during abortion.

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  1. A 17-year-old G1 P0 patient who is 5 weeks pregnant presents for uterine aspiration. As you insert the speculum, the cervix looks inflamed and friable and has pus at the os.
    • CT / GC testing and initiation of empiric pre-procedural treatment is indicated, as cervical infection with these pathogens increases risk of postabortion endometritis (Achilles 2011). Uterine aspiration should not be postponed. An appropriate treatment regimen (CDC 2021 Guidelines) includes:
      • Chlamydia: Doxycycline 100 mg orally twice daily for 7 days is the recommended regimen. Alternatively can use Azithromycin 1 gm single oral dose OR Levofloxacin 500 mg daily for 7 days
      • Gonorrhea: Ceftriaxone 500 mg intramuscular* PLUS treatment for Chlamydia. *For persons weighing ≥ 150 kg dose is Ceftriaxone 1 g intramuscular.
    • Symptomatic BV at the time of aspiration should be treated with metronidazole 500 mg orally twice daily for 7 days, without need to delay the abortion.

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  1. 40-year-old G4P3 patient at 7w4d presents for an abortion procedure. They have a BMI of 35 and a history of three previous cesareans.
    • The patient’s BMI and previous cesarean sections put this patient in the moderate risk category for hemorrhage (Kerns 2013) and a possibly challenging uterine aspiration. Consider medication abortion for this patient.
    • If considering aspiration abortion, the following should be considered:
      • Have uterotonic medications and supplies accessible to manage bleeding.
      • Add vasopressin to paracervical block.
      • Consider intraoperative US guidance.
      • With additional risk factors, consider referring to a center with transfusion capability, anesthesia, and / or interventional radiology. BMI alone does not require transfer from an outpatient facility (Benson 2016).

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  1. A 29-year-old G5 P2 patient presents for aspiration, with history of venous thromboembolism, currently anticoagulated on warfarin; last INR was in the therapeutic range. How would your management change if 10 wk vs. >14 wk EGA.
    • Procedural abortion is generally preferred over medical management for individuals with bleeding disorders or who are on anticoagulation. First-trimester procedural abortion in an individual on anticoagulation can generally be done without interruption of anticoagulation (Lee 2021). Additional blood loss in anticoagulated patients was not clinically significant in a small study of anticoagulated 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.
    • If the patient is 14+ weeks EGA or has other bleeding risks, consider referring to higher level of care.

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  1. A 26-year-old G2 P1 patient with a history of insulin-dependent diabetes presents for an aspiration at 8 weeks gestation. A preoperative glucose level is 520 mg/dL.
    • For patients with insulin dependent diabetes, check blood sugar, and if > 400, take history for diabetic control medications and whether taken today, trends, A1c, and history of recent care.
    • Mild hyperglycemia(200-400 mg/dL) is not a contraindication for uterine aspiration.
    • Above 400, assess for ketoacidosis (including urine dip for ketones and assess volume status); if + ketones or poor volume status, stabilize or refer prior to the procedure.
    • Hypoglycemia (<70 mg/dL) warrants a patient to be given dextrose or food prior to a procedure.


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