According to the 1996 Swedish study by Stener-Victorin et al, electro-acupuncture may increase blood flow to the uterus and therefore may increase endometrial receptivity in an IVF transfer.
This is significant because there is a lower rate of pregnancy when there is a high blood-flow impedance in the uterine arteries (measured by a pulsatility index, or PI of >=3) during an IVF cycle.
In the study, ten healthy women with the diagnosis of infertility and a high PI (>=3) were given electro-acupuncture (EA). Prior, the women were down-regulated with a gonadotropin releasing hormone analogue (GnRHa) so endogenous hormones would not interfere with the PI.
What was the acupuncture prescription and dosage?
The acupuncture points were bilateral BL23, BL28, SP6, and BL57. Each needle was inserted 10-20mm in depth, and manipulated to create a needle sensation. They were “then attached to an electrical stimulator for 30 min.”
BL23 and BL28 “were stimulated with high frequency (100 Hz) pulses of 0.5 ms duration. The intensity was low, giving non-painful paraesthesia.”
SP6 and BL57 “were stimulated with low frequency (2 Hz) pulses of 0.5 ms duration. The intensity was sufficient to cause local muscle contractions.”
The dosage of EA was 8 times (twice a week for 4 weeks).
How does electro-acupuncture (EA) potentially increase blood flow to the uterus?
The PI was significantly reduced after the 8th treatment and 10-14 days after the EA period. This suggests that EA may increase uterine artery blood flow by decreasing the “tonic activity in the sympathetic vasoconstrictor fibres to the uterus.”
Since EA creates a central inhibition of the sympathetic system, it may be why the skin temperature on the forehead (STFH) during and after EA treatments were elevated.
The reduction in PI may also be caused by EA’s local stimulation of sensory nerve fibers. The “sympathetic outflow may be inhibited at the segmental level and, for this reason, acupuncture points were selected in somatic segments according to the innervation of the uterus (T12-L2, S2-S3).”
Are there any flaws in this study?
There are potential flaws in this study. There is a lack of a control arm. The sample size is small (of the 10 women recruited, 2 were excluded from the study for a total of only 8 patients). To verify these results, further randomized controlled studies should be conducted with a larger sample size.
Study Referenced: Stener-Victorin, E., Waldenstrom, U., Andersson, S. A., & Wikland, M. (1996). Reduction of blood flow impedance in the uterine arteries of infertile women with electro-acupuncture. Human Reproduction