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Updated: Jan 15, 2026

External Cephalic Version: Is it an Effective and Safe Procedure?
Published on: June 6, 2020
Delayed Administration of Carboprost Methylate Reduces Perioperative Complications Without Affecting Cervical
Yifei Zhao1, Wei Xue2, Weilin Chen2
1Department of Anesthesiology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, People's Republic of China.
Aim:
This study aimed to investigate whether optimizing the timing of vaginal administration of carboprost methylate (CM), a prostaglandin F2α analogue, could ensure surgical safety and effectiveness while minimizing its side effects.
Methods:
This randomized controlled trial included 120 patients undergoing surgical abortion who were equally divided into two groups in a tertiary hospital. Group A received CM about 2 h before surgery, while group B received the medication just before anesthesia. The primary outcome was the cervical dilation time and the secondary outcomes included parameters of surgery completeness (surgery time, blood loss, and first-pass success rate of 7.5 Hegar dilator) and adverse events (abdominal pain, vomiting, nausea, diarrhea, defecation urgency, and fever).
Results:
The cervical dilation time and parameters of surgery completeness were similar between the two groups, and the concentration of cervical matrix metalloproteinase was no different. However, adverse events related to CM were significantly lower in group B than in group A (93.4% vs. 28.8%, p < 0.01) before anesthesia. The abdominal pain numerical rating scale (NRS) score before anesthesia was 10 times higher in group A (2.84 ± 2.11 vs. 0.27 ± 0.53, p < 0.01). Postoperative vomiting and nausea (PONV) percentage were significantly lower in group B (6.7% vs. 19.0%, p = 0.04).
Conclusion:
Delayed administration of CM until before anesthesia is effective in cervical priming for surgical abortion in early pregnancy and significantly reduces adverse symptoms, including PONV, diarrhea, and abdominal pain.
Trial Registration:
ClinicalTrials.gov: NCT05834361.

