Pain Relief with Low-Intensity Focused Ultrasound After First-Trimester Surgical Abortion: A Multicenter, Randomized Controlled Trial

INTERVENTION: treatment group:low intensity focused ultrasound therapy;control group:sham treatment; CONDITION: Postoperative Analgesia for Induced Abortion PRIMARY OUTCOME: NRS (Numerical Rating Scale) pain score; SECONDARY OUTCOME: 15‐minute post‐treatment NRS score reduction value;patient departure time;NRS score reduction at departure; INCLUSION CRITERIA: 1. Age >= 18 years; 2. Patients with early intrauterine pregnancy undergoing induced abortion for pregnancy termination; 3. Patients with a post‐abortion NRS (Numerical Rating Scale) pain score >= 4; 4. Signed informed consent and voluntary participation in the trial.