Induced abortion refers to the termination of pregnancy using artificial methods due to unintended pregnancy, medical conditions, or other reasons. It is considered a remedial measure for contraceptive failure. Induced abortion can have an impact on women’s reproductive health. Effective contraceptive measures aimed at preventing or reducing unintended pregnancies are an essential part of reproductive planning. Methods of induced abortion for early pregnancy termination include surgical abortion and medical abortion.
Surgical Abortion
Surgical abortion involves the termination of pregnancy using surgical techniques, including vacuum aspiration and dilation and curettage (D&C).
Vacuum Aspiration
Vacuum aspiration is the removal of pregnancy tissue from the uterine cavity using suction created by negative pressure.
Indications
These include:
- Early pregnancy (within 10 weeks) where the patient requests termination and has no contraindications.
- Severe medical conditions in which pregnancy continuation poses a significant health risk.
Contraindications
These include:
- Genital tract infections.
- Acute phases of systemic illnesses.
- Poor general health that makes the procedure intolerable.
- Two consecutive preoperative temperature measurements of ≥37.5°C.
Preoperative Preparation
This involves:
- Collecting a detailed medical history and performing a comprehensive physical and gynecological examination.
- Confirming pregnancy through blood or urine hCG testing and ultrasound.
- Conducting additional laboratory tests, including routine vaginal discharge analysis, complete blood count, and coagulation function tests.
- Monitoring vital signs such as temperature, pulse, and blood pressure before surgery.
- Providing education through various means (e.g., counseling or one-on-one consultation) to ensure patients fully understand the risks of surgery and the potential impact on fertility, while also recommending and guiding the use of effective contraceptive methods immediately following the procedure.
- Obtaining informed consent.
- Ensuring the bladder is emptied.
Surgical Procedure
The patient is placed in the lithotomy position. Sterilization procedures are performed on the vulva and vagina, followed by the placement of sterile drapes. A bimanual examination is conducted to assess the position, size, and adnexa of the uterus. A speculum is used to retract the vaginal walls and expose the cervix, which is sterilized. The anterior cervical lip is secured with cervical forceps. The uterine cavity depth is measured using a uterine probe inserted in the direction of the uterine axis. The cervix is gradually dilated using progressively larger dilators until it is slightly wider than the size of the suction cannula to be used. A suitable suction cannula is connected to the vacuum aspirator and gently inserted into the uterine cavity up to the fundus; upon encountering resistance, the cannula is slightly retracted. Negative pressure is typically maintained at 400–500 mmHg. The uterine cavity is swept in a clockwise direction 1 to 2 times. A gritty sensation typically indicates complete removal of pregnancy tissue. At this point, the rubber tubing is pinched, and the cannula is removed. A small curette is then used to lightly scrape the fundus and uterine horns to ensure complete evacuation. If necessary, the cannula is reinserted, and a second low-pressure vacuum sweep is performed. The cervical forceps are removed. The cervix and vagina are cleaned with a cotton ball to remove residual blood. The procedure is concluded. The uterine contents are filtered to measure the volume of blood and pregnancy tissue, and chorionic tissue is checked. In the absence of chorionic tissue, a pathology examination is performed, along with ultrasound imaging, to rule out incomplete evacuation.
Points of Attention
These include:
- Proper assessment of uterine size and orientation, with gentle manipulation to minimize tissue damage.
- Even application of pressure when dilating the cervical canal to prevent cervical tears.
- Strict adherence to sterile surgical protocols.
- Anesthesia should be administered and monitored by a trained anesthesiologist to prevent complications related to anesthesia.
- Pregnancies of 10 weeks or later are typically managed with D&C. In such cases, mechanical or pharmacological methods to soften the cervix are recommended to reduce the risk of complications such as intraoperative bleeding, cervical lacerations, or uterine perforation. Fetal and placental tissues must be carefully inspected postoperatively to confirm their completeness.
- In cases involving high-risk factors, intraoperative ultrasound guidance is recommended to enhance surgical safety.
Postoperative Management and Follow-Up
High-efficiency contraceptive methods should be implemented immediately following the procedure. For example, an intrauterine device can be inserted immediately after vacuum aspiration, depending on the patient’s requirements for contraception.
Postoperative observation should last 1–2 hours, ensuring minimal vaginal bleeding before discharge.
The vulva should be kept clean after the surgical procedure.
Sexual activity should be avoided for one month.
Follow-up visits should be scheduled at two weeks, one month, and three months postoperatively. The two-week visit primarily involves checking for any retained pregnancy tissue in the uterine cavity, while the one- and three-month follow-ups focus on endometrial recovery and contraceptive method use.
Complications of Induced Abortion and Their Management
Post-Abortion Syndrome
Post-abortion syndrome refers to a set of symptoms caused by pain or local stimulation during the procedure, leading to vagus nerve reactions. Patients may experience nausea, vomiting, bradycardia, arrhythmia, pallor, dizziness, chest tightness, cold sweats, and in severe cases, a drop in blood pressure, syncope, or convulsions. This condition is influenced by the patient’s emotional state, physical health, and the surgical approach. The incidence of these symptoms has decreased due to the use of anesthesia in most abortion procedures. Symptoms generally resolve with oxygen administration after halting the procedure. Severe cases may require intravenous atropine (0.5–1 mg). Counseling and reassurance before surgery, gentle operation during the procedure, and controlled suction pressure during uterine evacuation, along with minimizing unnecessary repeated curettage, can significantly reduce the occurrence of post-abortion syndrome.
Bleeding
Significant bleeding may occur in pregnancies further along (later in the first trimester) due to the larger uterus and suboptimal uterine contraction. This can be managed by cervical injection of oxytocin after cervical dilation, followed by prompt removal of the chorionic tissue. Bleeding may also result from inadequate suction pressure, undersized suction cannula, or overly soft tubing, necessitating adjustments to the equipment.
An increase in cesarean deliveries has led to a notable rise in cesarean scar pregnancies, which require heightened attention from the operator. Additional imaging may be necessary, and contingency plans should be in place for intraoperative crises.
Pregnancies complicated by coagulation disorders or other conditions affecting clotting require preoperative treatment to prevent excessive intraoperative bleeding.
Uterine Perforation
Uterine perforation is a serious complication of induced abortion, with its frequency linked to the surgeon’s skill and the condition of the uterus (e.g., pregnancy during breastfeeding, cesarean scar pregnancies). A sudden lack of resistance during the procedure or extension of surgical instruments beyond the measured uterine depth may suggest uterine perforation. Once detected, the procedure is suspended. For small perforations with no organ damage or internal bleeding, and if the procedure is complete, treatment involves conservative management with uterotonics and antibiotics to prevent infection. Vital signs such as blood pressure and pulse should be closely monitored. If uterine contents remain, an experienced surgeon may complete the procedure under ultrasound guidance or laparoscopic assistance, avoiding the perforation site. For large perforations, suspected internal bleeding, or organ injury, exploratory laparotomy or laparoscopy may be necessary, with subsequent management based on findings. If no evacuation has been performed and there is no bleeding, uterine evacuation may be delayed for one week.
Incomplete Suction or Empty Suction
Incomplete suction refers to partial retention of fetal or chorionic tissue, leading to continued pregnancy or fetal demise. This is often associated with uterine anomalies, abnormal uterine positioning, or insufficient surgical technique. A repeat vacuum aspiration is warranted when incomplete suction is diagnosed. Empty suction occurs when a misdiagnosed intrauterine pregnancy is targeted, resulting in the absence of chorionic tissue in the extracted material. Post-procedure, if chorionic tissue is not visually detected, repeated pregnancy tests and ultrasound are performed to confirm the absence of an intrauterine gestational sac. All extracted tissue is sent for pathological examination, and ectopic pregnancy should be ruled out as a potential diagnosis.
Incomplete Evacuation
Incomplete evacuation refers to the retention of parts of the pregnancy tissue after the procedure and is one of the most common complications of induced abortion. It is associated with technical inexperience or abnormal uterine positioning. Prolonged vaginal bleeding, heavy bleeding, or recurrent bleeding after an initial cessation may suggest incomplete evacuation. Diagnosis can be supported by blood or urine hCG testing and ultrasound. Depending on the situation, treatment could involve conservative management with medication or uterine evacuation. Uterine evacuation can be performed when there are no significant signs of infection. All removed tissue is sent for pathological analysis, followed by prophylactic antibiotic therapy postoperatively. In cases of concurrent infection, evacuation is delayed until the infection is controlled.
Infection
Infections such as acute endometritis or pelvic inflammatory disease may occur, necessitating treatment with antimicrobial agents administered orally or intravenously.
Amniotic Fluid Embolism
This rare complication can result from cervical damage or placental separation, allowing for the entry of amniotic fluid into open venous sinuses. In cases where it occurs, symptoms during early pregnancy are usually less severe compared to late pregnancy. Treatment focuses on managing allergic and shock-related symptoms.
Long-Term Complications
Repeated induced abortions can have detrimental effects on women’s reproductive health. Long-term complications may include cervical adhesions, intrauterine adhesions, chronic pelvic inflammatory disease, adenomyosis, menstrual irregularities, and secondary infertility. Subsequent pregnancies may carry risks such as fetal growth restriction, preterm birth, placenta previa, placental abruption, and other obstetric complications.
Medical Abortion
Medical abortion is a remedial measure for contraceptive failure that terminates early pregnancy through the use of medications. The drugs currently used in clinical practice are mifepristone and misoprostol. Mifepristone is a steroidal antiprogestin with both anti-progesterone and glucocorticoid-antagonistic properties. Misoprostol is a prostaglandin analog that induces uterine contractions and softens the cervix. When used in combination, the complete abortion rate for early pregnancy exceeds 90%.
Indications
These include:
- Early pregnancy (≤49 days) may be terminated in an outpatient setting with medical abortion. For pregnancies >49 days, inpatient abortion may be considered as needed.
- Voluntary request with blood or urine hCG positivity and ultrasound confirmation of intrauterine pregnancy.
- Presence of high-risk factors for surgical abortion, such as a scarred uterus, lactation, cervical dysplasia, or severe pelvic anomalies.
- A history of multiple surgical abortions or psychological fear and concern regarding surgical abortion.
Contraindications
These include:
- Contraindications to mifepristone use, including adrenal or other endocrine disorders, a history of pruritus gravidarum, hematological conditions, or thromboembolic diseases.
- Contraindications to prostaglandin medications, such as cardiovascular diseases, glaucoma, asthma, epilepsy, or colitis.
- Pregnancy with an intrauterine device in situ or suspected ectopic pregnancy.
- Other conditions, including allergic constitution, hyperemesis gravidarum, or long-term use of medications such as antituberculosis drugs, antiepileptic drugs, antidepressants, or antiprostaglandin medications.
Medication Protocols
Mifepristone can be administered in two ways: single-dose or divided-dose. For the single-dose method, 200 mg is taken orally at once. For the divided-dose method, a total of 150 mg is used: 50 mg is taken on the first morning, followed by 25 mg 8–12 hours later; on the second day, 25 mg is taken both morning and evening; on the third morning, the final 25 mg dose is taken.
For both methods, 0.6 mg of misoprostol is taken orally on the third morning after mifepristone administration. All medications are taken on an empty stomach, with fasting for at least one hour before and after administration. Gastrointestinal symptoms such as nausea, vomiting, abdominal pain, or diarrhea may occur after taking the medication.
Points of Attention
Medical abortion must be conducted in medical institutions equipped with standardized emergency care capabilities.
The procedure must be carried out under the supervision of medical professionals, with close monitoring of bleeding and potential side effects.
Ectopic pregnancy, hydatidiform mole, and other conditions must be carefully ruled out prior to medication use to avoid misdiagnosis or missed diagnosis.
Prolonged bleeding or excessive bleeding is the primary side effect of medical abortion. In rare cases, heavy bleeding may necessitate emergency surgical intervention to terminate the pregnancy.
After medical abortion, effective contraceptive methods should be implemented. Combined oral contraceptive pills can be initiated immediately following the procedure.