Table 1. Characteristics of selected studies.
| Author | Study type | Acupuncture group | Control group | Acupuncture type | Acupoints | Treatment session | Follow-up, weeks |
|---|---|---|---|---|---|---|---|
| Lee 2008 (12) | RCT | 44 | 45 | MA | CV1, CV4, SP6, SP9 | 20 | 34 |
| Qin 2018 (23) | RCT | 34 | 34 | MA | BL23, BL33, BL35, SP6 | 24 | 32 |
| Sahin 2015 (24) | RCT | 50 | 50 | MA | BL33, BL34, BL54, CV1, CV4, SP6, SP9 | 6 | 24 |
| Zhou 2017 (25) | RCT | 38 | 39 | EA | BL30, BL35 | 6 | 24 |
| Chen 2003 (26) | Case series | 12 | NA | MA plus EA | BL10, BL23, BL28, BL35, BL39, BL40, BL54, BL67, KI1, KI10, CV3, CV4, SP6 | 12 | 33 |
| Tugcu 2010 (27) | Case series | 93 | NA | MA | BL33 | 6 | 24 |
RCT, randomized controlled trial; NA, not available; MA, manual acupuncture; EA, electroacupuncture; CV, conception vessel; SP, spleen meridian; BL, bladder meridian; KI, kidney meridian.