The participants in the electroacupuncture at'four sacral points'group will receive treatment that consists of 8 acupuncture sessions over an 4-week period after baseline (2 sessions in each week), each for 30 minutes. Hua Tuo brand disposable acupunctureneedles (size 0.40 × 100mm) and electronic needle therapy instrument SDZ-IIB will be used.The device will be set at a frequency of 2.0 Hz, continuous wave and a moderate intensity the patient can tolerate. Electrostimulation will be performed for 30 min during each treatment. BL30 (Baihuanshu )(both sides and BL35 (Huiyang )(both sides), were selected as acupoints protocol.BL30 is located on either side of the sacrococcygeal joint, approximately 1 cm from the joint. BL35 is in the buttock region, 0.5 cun lateral to the extremity of the coccyx.

The participants in the conventional electroacupuncture group will select RN3 (Zhongji), CV4 (Guanyuan), and ST28 (Shuidao, both sides), KL3 (Taixi).A needle measuring 0.25×40 mm will be inserted perpendicularly to a depth of 25- 40 mm to RN3, CV4 and ST28 and 0.5 cun to KL3 to induce a local sensation (distention or sourness).Subsequently, the electrodes from the SDZ-IIB electroacupuncture device will be connected to the needles at these points, with the anode connected to ST28 and RN3, the cathode connected to ST28 and CV4. The protocol includes the same duration, frequency of sessions and the parameter setting of electroacupuncture as for the'four sacral points'treatment.

For'four sacral points'group, Hua Tuo brand disposable acupuncture needles (size 0.40 × 100mm) and electronic needle therapy instrument SDZ-IIB will be used.Bilateral BL30 and BL35, were selected as acupoints protocol.

'Four sacral points'group consists of 8 sessions over an 4-week period after baseline(2 sessions in each week), each for 30minutes. The electroacupuncture will be set at a frequency of 2.0 Hz, continuous wave, a moderate intensity the patient can tolerate and 30 min during each treatment.

IPSS is a valid, reliable and sensitive measure for patients with lower urinary tract symptoms; it iswidely used in clinical practice and research to determine the severity of lower urinary tractsymptoms, including incomplete bladder emptying, frequency of urination, intermittency, urgency,weak urine stream, straining and nocturia. Each of the questions is rated from 0 (not at all) to 5(almost always). IPSS score ranges from 0 to 35, with higher score indicating more severe urinary symptoms.Significant effect was defined as most of the major symptoms and signs disappeared, and the score decreased between 60% and 89%.

Effective is that the main symptoms and signs disappear partially, and the score decreases by 30%-59%.

OABSS is a valid self-assessment questionnaire, four questions were set according to OAB syndrome to determine the severity of OAB, which include daytime and nighttime urination frequency, urgency, urge incontinence. Score range is 0-15, with higher scores indicating increasing symptom severity.