MEDICAL EVALUATION PRIOR TO ASPIRATION
History and Physical
- Review medical history, obstetrical and gynecologic history, medications, substance use and allergies. A screening tool can ensure a thorough history is obtained (sample here).
- Review information for the following medical conditions (Guiahi 2012):
- Cardiovascular (hypertension, valvular disease, arrhythmias)
- Pulmonary (asthma, active respiratory infection)
- Hematologic (bleeding and clotting disorders, anticoagulants, severe anemia)
- Hemorrhage risk factors: See Chapter 5: Managing Complications Table.
- Endocrine (diabetes, hyperthyroidism)
- Renal and hepatic disease (affecting drug metabolism & clearance)
- Neurologic (seizure disorder) or psychiatric (severe depression or anxiety)
- Abortion is an essential and urgent service. Delays should be minimized, especially in people with significant medical problems, as risk increases with advancing gestational age. Medical conditions occasionally warrant management or referral prior to abortion (see table below).
- Complete physical exam as indicated by history and patient symptoms.
- Patients choosing medication abortion with sure LMP do not need a pelvic exam.
- Pelvic and bimanual exam may be performed immediately prior to the procedure.
- Bimanual for uterine size and position (may be affected by fibroids or anomalies)
- Speculum exam can assess cervicitis warranting testing / treatment
Lab Tests if Indicated
Patients without underlying medical conditions do not need routine pre-abortion lab testing. Lack of testing is not a barrier to abortion access. Some labs indicated by history, exam or dating.
- Tests pertinent to underlying conditions
- Glucose for patients with IDDM
- INR for patients on certain anti-coagulants (Warfarin) > 12 weeks
- Rh (D) testing:
- Patients > 56 days from LMP with unknown Rh status. (NAF CPGs 2020)
- Medication abortion patients may forego Rh testing <70 days LMP.
- Document Rh status or informed waiver declining Rh testing >56 days.
- Can use donor card if Rh negative, chart, patient report, or lab.
- If patient wants no future children or declines testing, may forego Rh testing.
- Hemoglobin / Hematocrit
- Only if history or symptoms of anemia, (fingerstick; not complete CBC).
- Chlamydia (CT) / Gonorrhea (GC):
- For asymptomatic patients ≤ 25 or at increased risk (i.e. new or multiple sexual partners in last year). If not offered at facility, may refer for testing.
- If cervicitis on exam, test for GC/CT, and initiate empiric prior to aspiration.
- Universal antibiotic prophylaxis is supported by available evidence for aspiration abortion (Low 2012; Achilles 2011), and less clear for aspiration for EPL (Lissauer 2019). See Chapter 5 for regimens.
Selected Health Condition Considerations and Management in First Trimester Aspiration Abortion Adapted from Ipas 2016 |
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Health Condition | Considerations |
Hypertension (HTN) |
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Seizure Disorder |
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Anemia |
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Blood-clotting disorders |
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Insulin-Dependent Diabetes |
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Heart Disease |
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Asthma |
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Active respiratory infection |
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Cervical Stenosis |
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Uterine Fibroids |
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Previous Cesarean Delivery |
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Alcohol or substance use disorders> |
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ULTRASOUND: OVERVIEW, METHODS, TIPS & IMAGES
Ultrasound can be used for pregnancy dating when clinical dating is uncertain. Ultrasound can also be used to determine pregnancy location, viability, and / or provide procedural support. Ultrasound is not a requirement for medication abortion or uterine aspiration.
Whether to use transabdominal or transvaginal ultrasound depends on patient preference, pregnancy dating, and the skill of the sonographer. Transabdominal ultrasound may be used to confirm intrauterine pregnancy (IUP) and date a pregnancy, although if landmarks are unclear or pregnancy is early, transvaginal ultrasound may be helpful. Generally, transvaginal ultrasound gives a good view of the pregnancy landmarks and can be helpful to rule out ectopic pregnancy or early pregnancy failure.
Transabdominal Probe | Transvaginal Probe |
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- A limited first trimester ultrasound exam must include: (NAF CPGs 2020)
- Uterine scan in both longitudinal and transverse planes to confirm IUP
- Evaluation of pregnancy number (singleton or multiple gestation)
- Measurements to document pregnancy dating
- Evaluation of pregnancy landmarks, such as yolk sac, embryonic pole, or the presence or absence of fetal/embryonic cardiac activity
When Performing US
- Ask if the patient wants to view image, be informed of multiple gestations or other pregnancy findings.
- Inform the patient that ultrasound is being used only to confirm the location and dating of the pregnancy and is not a diagnostic ultrasound.
- Consider starting your scan with transabdominal US, and switching to vaginal US only if you are unable to effectively visualize the pregnancy.
- For vaginal ultrasound, use a non-latex probe cover or condom, with ultrasound gel inside and lubricating jelly outside, where in contact with patient.
- Ask if the patient would prefer to self-insert the ultrasound probe.
- Use clear and simple language to discuss ultrasound findings with the patient.
- Systematically scan in the longitudinal and transverse planes.
TVUS planes (Image ARMS 2007)
- Longitudinal view is used to confirm pregnancy is intrauterine. For longitudinal view, notch is up (at 12 o’clock) and uterus is scanned side to side, from ovary to ovary. This view should show uterine fundus connected to cervix with pregnancy inside the uterus.
- Transverse view is used for dating and pregnancy landmarks, to evaluate for multiple gestations, and get full 3D image of the uterus. For transverse view, the probe is turned 90 degrees to the patient’s right (counterclockwise or notch turned to 9 o’clock) and uterus is scanned anterior to posterior, from fundus to cervix.
Clinicians should understand the sonographic pregnancy features that should be visible based on the patient’s last menstrual period.
Pregnancy Landmarks by Weeks LMP | |
Gestational Sac | 4.5 – 5 weeks LMP |
Yolk Sac | 5.5 weeks LMP |
Embryonic Pole | 6 – 6.5 weeks LMP |
Cardiac Activity | 6 – 6.5 weeks LMP |
*Above landmarks are better characterized using transvaginal ultrasound
ULTRASOUND LANDMARKS IN EARLY PREGNANCY
The Gestational Sac
- Gestational Sac (GS) is first single US evidence of pregnancy, can appear as early as 4.5 weeks LMP; should always be seen by 5 weeks 5 days LMP (Barnhart 2012).
- Although location of a pregnancy cannot definitely be diagnosed as intrauterine until a yolk sac or embryo is seen (Richardson 2015), a gestational sac still has a high likelihood of being an IUP even in the absence of certain sonographic features if there is no adnexal mass (Benson 2013, Phillips 2020).
- A true gestational sac should be located in the mid to upper portion of the uterus, be eccentric (not midline) to the endometrial canal, be round or oval in shape, and have the double decidual (or double ring) sign, as demonstrated by the FEEDS mnemonic below.
- Meeting these criteria does not completely exclude the possibility of ectopic pregnancy (Fjerstad 2004).
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- F – Fundal (in mid to upper uterus)
- E – Elliptical or round shape in 2 views
- E – Eccentric to the endometrial stripe
- D – Decidual reaction (surrounded by a thickened choriodecidual reaction; appears like fluffy white cloud or ring surrounding sac)
- S – Size > 4 mm (soft criteria)
Gestational Sac vs. Pseudosac
Pseudosac
(May be associated with ectopic)
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Image: Fjerstad M, et al. CAPS, 2004 | Image: Dr Matt A. Morgan, Radiopaedia.org, rID: 34217 |
The Yolk Sac
The Yolk Sac (YS) is first single US finding that confirms an IUP. The YS is a round echoic ring with anechoic (dark) center seen within GS. It appears typically at 5 ½ weeks when the MSD is 5-10 mm. The YS should not be included when taking a measurement of the embryo.
The size of the YS is not diagnostic.
The Embryo and Cardiac Activity
The embryo follows a predictable path of development and therefore can be used to date a pregnancy based on its size. The embryo appears at approximately 6 weeks and grows 1 mm per day thereafter until 12-14 weeks. See below for pregnancy dating using embryonic and fetal measurement. Cardiac activity appears around 6 ½ weeks.

Image from AIUM 2018
Determining Pregnancy Viability
The following data on viability evaluated patients with desired pregnancies (Doubilet 2013). If a pregnancy is undesired, there is no reason to delay an abortion to wait for confirmation of viability. If a pregnancy is desired, and findings are suggestive of early pregnancy loss (see table below), recheck ultrasound in 7-10 days.
Guidelines for TVUS Diagnosis of Early Pregnancy Loss in a Patient with an IUP of Uncertain Viability
(Adapted from Doubilet 2013, ACOG 2018)
US findings DIAGNOSTIC of EPL | US findings HIGHLY SUGGESTIVE of EPL † |
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EARLY PREGNANCY DATING USING ULTRASOUND
Crown Rump Length (CRL) Measurement and Calculation of Gestational Age: | |
Calculate: GA (days) = CRL (mm) + 42 |
![]() Image: AIUM 2018 |