Adverse event reporting in studies of penetrating acupuncture during pregnancy: a systematic review

This systematic review conducted a comprehensive analysis of the quality of adverse event reporting in studies of penetrating acupuncture during pregnancy, examining 17 studies that included 1,919 pregnant women between 2000 and 2014. The main objective was to investigate the quality of adverse event reporting and identify trends in their occurrence, type, and severity, comparing groups that received penetrating acupuncture with non-acupuncture control groups. Methodology included systematic searches in the MEDLINE, CINAHL, AMED, and PEDro databases, with assessment of study quality using the PEDro and Downs and Black scales, and analysis of reporting quality according to STRICTA and CONSORT guidelines. Results revealed that the overall quality of adverse event reporting was poor, with information frequently vague or incomplete.

Only two of the 17 studies provided adequate data on adverse events. The analysis showed that adverse events occurred in 3-17% of acupuncture sessions versus 4-25% in control sessions, affecting 14-17% of women in the acupuncture group and 15-19% in the control group. Most adverse events were classified as non-serious and transient, including symptoms such as dizziness, drowsiness, local pain at the needle insertion site, mild nausea, and fatigue. Only one serious adverse event was recorded — preterm labor — which was possibly related to acupuncture, representing a rate of 1 case in 1,193 treated women.

Importantly, this event did not result in lasting consequences for mother or baby. The types of adverse events reported were similar between acupuncture and control groups, including taste alterations, tiredness, discomfort during treatment, mild uterine contractions, and localized pain. No study found lasting adverse effects on the fetus or newborn attributable to acupuncture. The clinical implications suggest that acupuncture during pregnancy presents a safety profile comparable to other non-invasive interventions, with adverse events predominantly mild and self-limited.

This is particularly relevant considering that acupuncture has shown efficacy for several pregnancy-related conditions, such as lumbopelvic pain, nausea and vomiting, depression, and gestational insomnia. The review identified several important limitations. The main one was the inconsistent and frequently inadequate quality of adverse event reporting in primary studies, hindering accurate risk assessment. Many studies did not follow STRICTA and CONSORT guidelines for adequate reporting, failing to clearly specify whether adverse events were attributable to the interventions or to provide sufficient information about participant dropout.

The heterogeneity of studies in terms of population, conditions treated, and acupuncture methodologies also limited the ability to make direct comparisons. For clinical practice, the results suggest that practitioners can inform pregnant women that acupuncture presents minimal risks when properly performed, with adverse events generally mild and temporary. However, informed consent should include discussion of possible effects such as local tenderness, mild dizziness, or transient fatigue. The review emphasizes the need for better standardization in adverse event reporting in future research, following established guidelines to ensure transparency and allow more accurate safety assessments.

Future studies should implement rigorous safety monitoring protocols and detailed reporting of all adverse events, regardless of perceived severity.