Medical Abortion

Medical abortion (MA) is the termination of an early intrauterine pregnancy using medications instead of a surgical procedure, most often a combined mifepristone-misoprostol regimen. Mifepristone blocks progesterone receptors, destabilizing the pregnancy and priming the cervix and uterus to respond to a prostaglandin; misoprostol, given afterward, induces uterine contractions that expel the pregnancy.^[1] In Canada, mifepristone-misoprostol (dispensed as the co-packaged product Mifegymiso) is the regimen of choice and the only combination formally approved by Health Canada for this indication^[2], though a misoprostol-only regimen remains a real, evidence-based alternative when mifepristone cannot be used, and a methotrexate-misoprostol regimen exists as a less commonly used further alternative. Pharmacists are central to safe MA care: dispensing the two-drug sequence with correct counselling on timing and route, anticipatory guidance on the expected bleeding and pain pattern versus red-flag symptoms, and helping ensure an effective post-abortion contraceptive plan is in place before the fertile window resumes.

The patient

The person presenting for MA is not describing a disease process but requesting termination of a confirmed or suspected early intrauterine pregnancy. The first clinical tasks are to confirm the pregnancy is intrauterine, establish gestational age, and confirm eligibility for medical rather than surgical management — see Assessment & Diagnosis for the differential between a normal early intrauterine pregnancy, a pregnancy of unknown location, and a suspected ectopic pregnancy.

The expected course once treatment starts

Once misoprostol is administered, most patients experience the onset of vaginal bleeding within a few hours, progressing to bleeding heavier than a typical menstrual period with clots and passage of tissue, accompanied by cramping that typically begins 2 to 4 hours after the misoprostol dose.^[1] Prostaglandin-related effects — nausea, vomiting, diarrhea, headache, dizziness, and transient chills or fever — are common on the day misoprostol is taken and are generally self-limited.^[1] Most patients complete the process within days, though intermittent bleeding and spotting can continue for one to two weeks afterward.

• Risk factors for ectopic pregnancy that must be excluded before proceeding with MA: previous ectopic pregnancy, tubal surgery or tubal ligation, pregnancy conceived through assisted reproductive technology, an intrauterine device in place, and a history of salpingitis or pelvic inflammatory disease.
• Risk factors for incomplete abortion or treatment failure: higher maternal age, a greater number of previous pregnancies, and a history of spontaneous abortion.
• Factors favoring surgical over medical management: a hemorrhagic disorder or concurrent anticoagulant therapy, significant anemia, gestational age near the eligibility limit, and patient preference for a shorter, clinician-controlled procedure.
• An intrauterine device in place at the time of pregnancy diagnosis is itself a risk factor for ectopic pregnancy and requires ultrasound exclusion of ectopic pregnancy before MA; if the pregnancy is confirmed intrauterine and the device strings are visible, remove it before proceeding.

Distinguishing an eligible intrauterine pregnancy from a pregnancy of unknown location or ectopic pregnancy

Before any MA regimen is dispensed, pregnancy location must be established with enough certainty to exclude ectopic pregnancy — mifepristone-misoprostol and misoprostol-only regimens are not appropriate treatment for ectopic pregnancy and can delay its diagnosis given overlapping symptoms.^[1]

History

• Confirm the date of the last menstrual period and cycle regularity; in patients certain of their LMP with a regular cycle, LMP alone can establish gestational age.
• Obstetric and gynecologic history, including recent bleeding or pelvic pain, and any ectopic-pregnancy risk factors above.
• Full medical history relevant to contraindications: adrenal insufficiency, porphyria, uncontrolled asthma, inflammatory bowel disease, hemorrhagic disorder or anticoagulant use, known hypersensitivity to the regimen's components.
• Current medication list, including any hormonal contraceptive in use, and whether an intrauterine device or system is in place.
• Sexual history and STI risk, since chlamydia and gonorrhea are associated with increased post-abortion endometritis risk.
• Psychosocial history, decisional certainty, and screening for intimate partner violence or coercion — ambivalence about the decision is itself a contraindication to proceeding.

Physical examination

• Baseline vital signs (pulse, blood pressure, temperature).
• Weight, needed if a methotrexate-misoprostol regimen is being considered.
• Bimanual pelvic and abdominal examination — cervical softening and uterine enlargement can be appreciated as early as 6 to 8 weeks; a uterus larger or smaller than expected for the stated LMP warrants further evaluation (multiple pregnancy, fibroids, or molar pregnancy if larger; possible ectopic pregnancy if smaller).

Investigations — including when one is not indicated

• Hemoglobin to identify significant anemia, which raises the threshold for offering surgical management instead of MA.
• Baseline serum beta-hCG when pregnancy location is not yet confirmed by ultrasound — used both to work up a possible ectopic pregnancy or PUL, and as the reference value for confirming completion later.
• STI screening (urine or cervicovaginal swab for chlamydia and gonorrhea) as part of pre-abortion care.
• Ultrasound is not a mandatory prerequisite for MA in Canada — Health Canada removed the requirement for routine pre-treatment ultrasound from the Mifegymiso product information in April 2019.^[2] It remains required, rather than optional, when the patient has ectopic pregnancy risk factors or symptoms, when gestational age is uncertain, or when uterine size on examination does not match the stated LMP.
• Rh(D) typing — see Choose Initial Treatment for the current, evidence-based approach to Rh testing and anti-D immune globulin, which has changed substantially from older practice of routine testing beyond 49 days' gestation.

• Safely and completely terminate the confirmed, eligible intrauterine pregnancy without requiring surgical intervention.
• Exclude ectopic pregnancy before treatment and remain alert to it throughout, since MA does not itself treat or reliably rule out an ectopic pregnancy.
• Keep bleeding and pain within the expected range, with the patient equipped to recognize and act on red-flag symptoms.
• Detect and treat infection promptly if it occurs.
• Confirm complete abortion at follow-up, and move promptly to surgical management if it is not complete.
• Have an effective contraceptive method in place before the return of fertility, which can occur as early as 8 days after starting treatment.

Counselling and decision support

• Use nonjudgmental, nondirective language in a confidential setting; discuss all pregnancy options (continuing the pregnancy, adoption, abortion) unless the patient has already made a firm decision and does not wish to revisit it.
• A validated decision aid can help patients with genuine decisional uncertainty; proceeding with treatment should wait until the patient is certain, since ambivalence is itself a contraindication to starting MA.
• Explain that abortion is not associated with an increased risk of infertility, ectopic pregnancy, subsequent miscarriage, birth defects, or preterm/low-birth-weight delivery in a future pregnancy, and that patients are not at increased risk of depression, anxiety, or lower life satisfaction afterward.
• Offer trauma-informed care to every patient (privacy, choice, and safety) regardless of whether a specific trauma history is disclosed, and watch for factors associated with a harder emotional adjustment (history of depression, high decisional conflict, low social support, interpersonal violence).

Medical versus surgical abortion — counselling comparison

What to expect during treatment

• Use thick, full-sized sanitary pads to track bleeding — not tampons.
• Expect bleeding to start within a few hours of the misoprostol dose, heavier than a menstrual period, with clots and passage of tissue; cramping typically begins 2 to 4 hours after the misoprostol dose.
• Avoid sexual intercourse until follow-up confirms the abortion is complete.
• Every patient needs a clear plan for reaching emergency care at any hour, and should be told explicitly what symptoms mean "call now" versus what is expected.

Follow-up logistics

A reliable follow-up plan — in-clinic or remote (telephone/telemedicine) — should be arranged before the patient leaves the first visit, using clinical history combined with ultrasound and/or serial beta-hCG measurement; remote and in-clinic follow-up achieve similar completion and attendance rates and can be offered based on patient preference and access.^[1]

Managing an incomplete abortion without hemorrhage or infection

When retained products of conception are identified without heavy bleeding or signs of infection, expectant management (allowing the tissue to pass on its own) is a reasonable non-pharmacologic option alongside repeat misoprostol or surgical evacuation — see Treatment Failure & Next Step for the full decision sequence.

Pregnancy

Breastfeeding

Mifepristone and misoprostol both reach breast milk in low concentrations, and breastfeeding can continue through MA without interruption.^[1] Methotrexate transfers into breast milk and is contraindicated during breastfeeding — do not use the methotrexate-misoprostol regimen in a breastfeeding patient.

Adolescents

The same evidence-based regimens apply; provide age-appropriate, confidential counselling and follow local/provincial consent requirements for minors seeking abortion care.

Renal and hepatic impairment

Methotrexate is contraindicated in active liver disease or significant renal impairment — use mifepristone-misoprostol or the misoprostol-only regimen instead. No specific dose adjustment is described for mifepristone-misoprostol in renal or hepatic impairment; use clinical judgment and specialist input for significant impairment.

Multiple pregnancy

Not a contraindication to MA; the mifepristone-misoprostol regimen remains appropriate, though treatment success may be modestly lower than with a singleton pregnancy.^[1]

Long-term systemic corticosteroid therapy

Mifepristone can transiently reduce the effectiveness of corticosteroid therapy for 3 to 4 days after administration — adjust the corticosteroid dose accordingly in patients on long-term therapy for a non-adrenal-insufficiency indication (chronic adrenal insufficiency itself is an absolute contraindication to mifepristone).

Hemorrhagic disorders or anticoagulant therapy

Relative contraindication — MA is associated with more bleeding than surgical abortion, and that bleeding is unsupervised. Discuss surgical abortion as the preferred option with a patient who has a significant bleeding disorder or is on anticoagulant therapy.

All patients need a follow-up assessment 7 to 14 days after starting treatment to confirm the abortion is complete, delivered in-clinic or remotely (telephone/telemedicine) using clinical history combined with ultrasound and/or serial beta-hCG measurement.^[1] A fall in beta-hCG of 80% or more from the pre-treatment baseline to this follow-up indicates a completed abortion; a fall of less than 80% requires further investigation.^[1] When patient history alone is used — heavier-than-menses bleeding, passage of tissue, and resolution of pregnancy symptoms — both patient and clinician judging that expulsion has occurred is a reasonable basis to consider the abortion complete, without requiring routine ultrasound in every patient.^[1] If ultrasound is used, endometrial thickness alone does not predict the need for surgical intervention and should not be used in isolation to decide on aspiration.^[1] Reassess contraceptive uptake and effective use at this visit, and use it as the scheduled opportunity for delayed intrauterine device insertion if that is the patient's preferred method. Provide 24-hour access to emergency advice throughout the process, and document the follow-up plan clearly in the chart.

1. Confirm the regimen was actually taken as directed (both drugs, correct route and timing) before assuming pharmacologic failure.
2. If bleeding is heavy and uncontrolled, or infection is suspected, proceed directly to surgical (aspiration) management rather than a repeat medical attempt.
3. If ultrasound at follow-up shows a retained gestational sac without fetal cardiac activity, options are expectant management, a repeat dose of misoprostol, or aspiration, guided by the patient's symptoms and preference.
4. If fetal cardiac activity is present 7 to 14 days after mifepristone, options are a repeat misoprostol dose or aspiration; if cardiac activity persists 1 week after the misoprostol dose, proceed to aspiration.
5. Ongoing pregnancy 14 to 21 days after starting a mifepristone-misoprostol regimen should be offered surgical evacuation.
6. Ongoing pregnancy after a methotrexate-misoprostol regimen should proceed to surgical evacuation — this regimen is not repeated for a second attempted course.
7. If the beta-hCG fall is less than expected (less than 80% by 7-14 days, or less than 50% at 24 hours in an early-follow-up PUL protocol) without a clear alternative explanation, investigate further for ectopic pregnancy before assuming an ongoing intrauterine pregnancy.

• Proceeding with MA before ectopic pregnancy has been adequately excluded in a patient with risk factors, symptoms, or an elevated beta-hCG without a visualized intrauterine gestational sac.
• Treating early prostaglandin-effect symptoms (nausea, vomiting, diarrhea, abdominal pain) as automatically benign in a patient whose fever pattern, blood pressure, and heart rate instead fit toxic shock syndrome.
• Continuing to apply the older routine Rh-testing-beyond-49-days approach without recognizing that current guidance no longer supports routine Rh testing or anti-D under 12 weeks' gestation.
• Giving the methotrexate-misoprostol regimen to a breastfeeding patient — methotrexate is contraindicated during breastfeeding.
• Repeating a methotrexate-misoprostol regimen after ongoing pregnancy is confirmed — this scenario calls for surgical evacuation, not a second attempt.
• Leaving post-abortion contraception as an afterthought — return of fertility can occur within 8 days, well before most patients would otherwise think to arrange contraception.
• Delaying intrauterine device insertion indefinitely out of excess caution — insertion at the confirmed-complete follow-up visit has higher uptake than delayed insertion, with no clear safety advantage to waiting further.
• Assuming any bleeding after misoprostol confirms a completed abortion without applying an actual confirmation method (history plus ultrasound and/or serial beta-hCG).
• Missing that an intrauterine device in place at the time of pregnancy diagnosis is itself a red flag for ectopic pregnancy, not simply a device to remove and move on.

How to use this table: doses are adult doses and require patient-specific confirmation, including renal/hepatic adjustment. Select any drug name to open its complete Pharmasist Drug Database page.

Progesterone receptor modulator + prostaglandin combination

Prostaglandin analogue — misoprostol-only regimen

Folate antagonist + prostaglandin combination

A less commonly used alternative now that mifepristone-misoprostol is widely available in Canada.

Rh alloimmunization prevention

Pain management

NSAIDs are first-line; as-needed dosing is as effective as prophylactic dosing and does not reduce misoprostol's efficacy.

Nausea, vomiting, and diarrhea management (prostaglandin effects)

Emerging option — not currently approved by Health Canada for this indication

Included for awareness only; not standard Canadian practice.