Severity of pain and circadian changes in uterine artery blood flow in primary dysmenorrhea

Ultrasound and magnetic resonance imaging-based investigation of the role of perfusion and oxygen availability in menstrual pain

BACKGROUND

The mechanisms responsible for menstrual pain are poorly understood. However, dynamic, noninvasive pelvic imaging of menstrual pain sufferers could aid in identifying therapeutic targets and testing novel treatments.

OBJECTIVE

To study the mechanisms responsible for menstrual pain, we analyzed ultrasonographic and complementary functional magnetic resonance imaging parameters in dysmenorrhea sufferers and pain-free controls under multiple conditions.

STUDY DESIGN

We performed functional magnetic resonance imaging on participants with and those without dysmenorrhea during menses and outside menses. To clarify whether regional changes in oxygen availability and perfusion occur, functional magnetic resonance imaging R2∗ measurements of the endometrium and myometrium were obtained. R2∗ measurements are calculated nuclear magnetic resonance relaxation rates sensitive to the paramagnetic properties of oxygenated and deoxygenated hemoglobin. We also compared parameters before and after an analgesic dose of naproxen sodium. In addition, we performed similar measurements with Doppler ultrasonography to identify if changes in uterine arterial velocity occurred during menstrual cramping in real time. Mixed model statistics were performed to account for within-subject effects across conditions. Corrections for multiple comparisons were made with a false discovery rate adjustment.

RESULTS

During menstruation, a notable increase in R2∗ values, indicative of tissue ischemia, was observed in both the myometrium (beta ± standard error of the mean, 15.74±2.29 s-1; P=.001; q=.002) and the endometrium (26.37±9.33 s-1; P=.005; q=.008) of participants who experienced dysmenorrhea. A similar increase was noted in the myometrium (28.89±2.85 s-1; P=.001; q=.002) and endometrium (75.50±2.57 s-1; P=.001; q=.003) of pain-free controls. Post hoc analyses revealed that the R2∗ values during menstruation were significantly higher among the pain-free controls (myometrium, P=.008; endometrium, P=.043). Although naproxen sodium increased the endometrial R2∗ values among participants with dysmenorrhea (48.29±15.78 s-1; P=.005; q=.008), it decreased myometrial R2∗ values among pain-free controls. The Doppler findings were consistent with the functional magnetic resonance imaging (-8.62±3.25 s-1; P=.008; q=.011). The pulsatility index (-0.42±0.14; P=.004; q=.004) and resistance index (-0.042±0.012; P=.001; q=.001) decreased during menses when compared with the measurements outside of menses, and the effects were significantly reversed by naproxen sodium. Naproxen sodium had the opposite effect in pain-free controls. There were no significant real-time changes in the pulsatility index, resistance index, peak systolic velocity, or minimum diastolic velocity during episodes of symptomatic menstrual cramping.

CONCLUSION

Functional magnetic resonance imaging and Doppler metrics suggest that participants with dysmenorrhea have better perfusion and oxygen availability than pain-free controls. Naproxen sodium's therapeutic mechanism is associated with relative reductions in uterine perfusion and oxygen availability. An opposite pharmacologic effect was observed in pain-free controls. During menstrual cramping, there is insufficient evidence of episodic impaired uterine perfusion. Thus, prostaglandins may have protective vasoconstrictive effects in pain-free controls and opposite effects in participants with dysmenorrhea.

The effect of Ding-kun-dan comparing with Marvelon on primary dysmenorrhea: A prospective, double-blind, multicenter, randomized controlled trial

ETHNOPHARMACOLOGICAL RELEVANCE

Ding-kun-dan (DKD), as one of well-known traditional Chinese medicine (TCM), is considered as an effective prescription to regulate menstruation, benefit Qi and nourish the blood. Previous studies had showed that DKD could improve sex hormone levels, insulin resistance, metabolism abnormalities and regulate immunity in animal models with polycystic ovary syndrome or endometriosis, however, little study conducted to reveal its clinical efficacy in Primary Dysmenorrhea (PD).

AIM OF THE STUDY

To compare the effect of Ding-kun-dan (DKD) with Marvelon on relief of symptoms and change of serum pain-related factors in patients with primary dysmenorrhea.

MATERIALS AND METHOD

136 patients with primary dysmenorrhea were randomly assigned to the DKD group (n = 73, take one tablet per day from 5th day of the menstrual cycle for 10 days every 28 days) and the Marvelon group (n = 63, take one tablet per day from 5th day of the menstrual cycle for 21 days every 28 days), the therapeutic effects were analyzed through evaluating the change of VAS scores, CMSS scores and the level of PGF2a, PGE2, PGF2a/PGE2 and NO during the 12 weeks intervention.

RESULTS

Both DKD and Marvelon could effectively relief pain and other associated symptoms at each visit (Baseline, 4th week, 8th week and 12th week). Although Marvelon was significantly superior to DKD in reducing VAS scores, the total CMSS, CMSS severity and duration scores at each posttreatment follow-up (P < 0.01), VAS scores in the DKD group decreased significantly over time while scores in the COC group only dropped rapidly after the first two months of treatment. Efficacy gap between two interventions continuously narrowed over time and the efficacy of DKD became non-inferior at the 12th week compared to that of Marvelon (the difference between groups, - 0.78%; 95% confidence interval (CI), -13.67%-12.75%; non-inferiority margin, 15%). DKD group had better efficacy on mild pain compared to that of the COC group with no statistical difference (75% VS 61.9%, P > 0.05). DKD and Marvelon could effectively reduce PGF2a, PGE2 and higher PGF2a/PGE2 in patients with PD. There was no statistical difference in the level of PGF2a, PGE2, PGF2a/PGE2 and NO between DKD and Marvelon group at each follow-up. No serious adverse effect was observed.

CONCLUSION

Ding-kun-dan is another available, effective and safe method for patients with primary dysmenorrhea to choose, especially for those who are suffered from mild pain and/or contraindicated to hormonal agents.

The Effect of Exercise on Pulsatility Index of Uterine Arteries and Pain in Primary Dysmenorrhea

BACKGROUND

Primary dysmenorrhea (PD) is one of the most common diseases in women of reproductive age. Our aim was to examine whether a twice-weekly thirty-minute exercise intervention could result in a difference in the pulsatility index (PI) of the uterine arteries (UAs) and level of menstrual pain in patients with PD.

METHODS

In our prospective observational trial, the observation period included one spontaneous menstrual cycle and the consecutive time of the next menstruation of all participants, aged 18-44, with no extensive sports experience. In total, 73 volunteers were enrolled: 38 persons in the intervention group (IG) and 35 in the control group (CG). The intervention program was accompanied by music, performed in groups under the supervision of a qualified instructor in Hungary. The primary outcome was the difference between the IG and CG regarding the PI values of UAs at the 1st and the 2nd ultrasound (US) Doppler flowmetry. The secondary outcome was the difference between the IG and CG regarding the PI of UAs and menstrual pain measured by using the Numeric Rating Scale and adherence to the intervention. Statistical tests such as an independent-samples t-test, chi-square test, Mann-Whitney test and analysis of covariance (ANCOVA) were used during the analyses.

RESULTS

Examining the mean of the PI of UAs in the IG and the CG at the 1st and the 2nd US measurement, a significant difference was found in the change in the measured value (Z = -2.545; p = 0.011). The IG showed a significantly higher increase in the mean of the PI of UAs (Median = 0.825) than the CG (Median = 0.130). The difference in the PI of the UAs of the IG and the CG is not related to the level of pain in any group (p = 0.336) and not related to the whole sample (p = 0.354); furthermore, the level of pain did not significantly differ between the two groups.

CONCLUSIONS

Our study is the first to document the significant effects of mild-to-moderate exercise training on the change in the PI of the UAs in individuals with PD. The IG had a reduced blood flow due to circulatory redistribution after exercise. The level of menstrual pain of primary dysmenorrhea patients is independent of the level of blood circulation regarding the PI of the UAs. Randomized controlled studies with more participants and a longer research period are needed to confirm our findings regarding the association between regular exercise and the PI of UAs. The study was registered at clinicaltrials.gov: NCT04618172.

Dysmenorrhoea as a risk factor for pain with intrauterine device insertion

BACKGROUND

Understanding predictors of pain with gynaecological procedures may facilitate individualised counselling and pain management. We aimed to study the effect of dysmenorrhoea on intrauterine device (IUD) insertion pain.

METHODS

This was a planned secondary analysis of a randomised trial evaluating self-administered lidocaine gel versus placebo for IUD insertion pain. We included those participants who reported menses in the past 3 months. We assessed dysmenorrhoea (in the past 3 months) and procedural pain using a 100 mm visual analogue scale (VAS). We categorised dysmenorrhoea as none/mild (<40 mm), moderate (40-69 mm) or severe (≥70 mm). We assessed participant pain scores at speculum insertion, tenaculum placement, IUD insertion, and overall. We compared median procedural pain scores by dysmenorrhoea group with three-way and post hoc pairwise analyses.

RESULTS

We analysed 188 participants. Demographic characteristics were similar among the three dysmenorrhoea groups. Pairwise comparisons revealed higher median procedural pain scores in the severe dysmenorrhoea group compared with the none/mild dysmenorrhoea group at speculum insertion (25 mm vs 8 mm; p=0.007), tenaculum placement (51 mm vs 31 mm; p=0.04) and IUD insertion (74 mm vs 61 mm; p=0.04). Overall pain did not differ among the three groups (p=0.32).

CONCLUSIONS

Patients with severe dysmenorrhoea experienced increased pain with all aspects of IUD insertion, including speculum and tenaculum placement, compared with those with only mild or no dysmenorrhoea. Clinicians may consider this finding when providing individualised counselling and pain management for patients undergoing IUD insertion and other gynaecological procedures. Larger studies are needed to validate the effect of dysmenorrhoea severity on pain throughout IUD insertion.

The Relationship between Serum Ischemia-Modified Albumin Levels and Uterine Artery Doppler Parameters in Patients with Primary Dysmenorrhea

OBJECTIVE

 Primary dysmenorrhea occurs due to abnormal levels of prostanoids, uterine contractions, and uterine blood flow. However, the reasons for pain in primary dysmenorrhea have not yet been clarified. We examined the blood flow alterations in patients with primary dysmenorrhea and determined the relationship between ischemia-modified albumin (IMA) levels, as an ischemia indicator, and primary dysmenorrhea.

METHODS

 In the present study, 37 patients who had primary dysmenorrhea and were in their luteal and menstrual phase of their menstrual cycles were included. Thirty individuals who had similar demographic characteristics, who were between 18 and 30 years old and did not have gynecologic disease were included as control individuals. Their uterine artery Doppler indices and serum IMA levels were measured.

RESULTS

 Menstrual phase plasma IMA levels were significantly higher than luteal phase IMA levels, both in the patient and in the control groups (p < 0.001). Although the menstrual phase IMA levels of patients were significantly higher than those of controls, luteal phase IMA levels were not significantly different between the two groups. Menstrual uterine artery pulsatility index (PI) and resistance index (RI) of primary dysmenorrhea patients were significantly different when compared with luteal uterine artery PI and RI levels. There was a positive correlation between menstrual phase IMA and uterine artery PI and RI in the primary dysmenorrhea.

CONCLUSION

 Ischemia plays an important role in the etiology of the pain, which is frequently observed in patients with primary dysmenorrhea. Ischemia-modified albumin levels are considered as an efficient marker to determine the severity of pain and to indicate ischemia in primary dysmenorrhea.

A comparison of two different oral contraceptives in patients with severe primary dysmenorrhoea

Pain relief of two different oral contraceptive pills (OCPs) in severe primary dysmenorrhoea (PD) was compared. Sixty-six nulliparous patients with severe PD requiring contraception were evaluated. Group 1 comprised 33 healthy controls. Patients with severe PD were divided into two groups. Patients in Group 2 were administered oestradiol valerate/dienogest and patients in Group 3 were administered ethinylestradiol/drospirenone. Doppler indices of both uterine arteries (left and right) including systolic/diastolicrates (S/D), pulsatility index (PI) and resistance index (RI) were measured, and a visual analogue scale (VAS) was applied to patients before treatment. VAS scores and Doppler indices were repeated after 3 months of OCP treatment and the changes in values were compared. The demographic and clinical characteristics of the patients were similar. The mean value of RI was significantly lower after therapy in Groups 2 and 3 in the right and left uterine arteries (p = .001 and p = .039, respectively). The clinical trial number was NCT03124524. Impact Statement What is already known on this subject: OCPs are the most appropriate treatment option for PD. There is no clear data about OCP containing dienogest for treatment in PD. Dienogest has been reported to be highly effective in the treatment of endometriosis and is also recommended as first-line therapy for pelvic pain-associated endometriosis. What the results of this study add: In this study, although there was no superiority in pain relief between the treatment groups, lower VAS scores and lower RI values of uterine arteries were seen after treatment. Both OCPs relieve pain in severe PD. There was no serious adverse effect in the patients. What the implications are of these findings for clinical practice and/or further research: Estradiol valerate/dienogest, which is a routinely prescribed drug for heavy menstrual bleeding in women who desire oral contraception, is as effective as ethinylestradiol/drospirenone in pain relief.

Anticipated pain as a predictor of discomfort with intrauterine device placement

BACKGROUND

Intrauterine devices have been gaining popularity for the past 2 decades. Current data report that >10% of women who use contraception are using an intrauterine device. With <1% failure rates, the intrauterine device is one of the most effective forms of long-acting reversible contraception, yet evidence shows that fear of pain during intrauterine device placement deters women from choosing an intrauterine device as their contraceptive method.

OBJECTIVES

The objective of this analysis was to estimate the association between anticipated pain with intrauterine device placement and experienced pain. We also assessed other factors associated with increased discomfort during intrauterine device placement. We hypothesized that patients with higher levels of anticipated pain would report a higher level of discomfort during placement.

STUDY DESIGN

We performed a secondary analysis of the Contraceptive CHOICE Project. There were 9256 patients enrolled in Contraceptive CHOICE Project from the St. Louis region from 2007-2011; data for 1149 subjects who came for their first placement of either the original 52-mg levonorgestrel intrauterine system or the copper intrauterine device were analyzed in this study. Patients were asked to report their anticipated pain before intrauterine device placement and experienced pain during placement on a 10-point visual analog scale. We assessed the association of anticipated pain, patient demographics, reproductive characteristics, and intrauterine device type with experienced pain with intrauterine device placement.

RESULTS

The mean age of Contraceptive CHOICE Project participants in this subanalysis was 26 years. Of these 1149 study subjects, 44% were black, and 53% were of low socioeconomic status. The median expected pain score was 5 for both the levonorgestrel intrauterine system and the copper intrauterine device; the median experienced pain score was 5 for the levonorgestrel intrauterine system and 4 for the copper intrauterine device. After we controlled for parity, history of dysmenorrhea, and type of intrauterine device, higher anticipated pain was associated with increased experienced pain (adjusted relative risk for 1 unit increase in anticipated pain, 1.19; 95% confidence interval, 1.14-1.25). Nulliparity, history of dysmenorrhea, and the hormonal intrauterine device (compared with copper) also were associated with increased pain with intrauterine device placement.

CONCLUSION

High levels of anticipated pain correlated with high levels of experienced pain during intrauterine device placement. Nulliparity and a history of dysmenorrhea were also associated with greater discomfort during placement. This information may help guide and treat patients as they consider intrauterine device placement. Future research should focus on interventions to reduce preprocedural anxiety and anticipated pain to potentially decrease discomfort with intrauterine device placement.

Wenjing decoction (herbal medicine) for the treatment of primary dysmenorrhea: a systematic review and meta-analysis

PURPOSE

Wenjing decoction is a well-accepted traditional Chinese medicine for the treatment of primary dysmenorrhea in East Asia, but its clinical effectiveness and risk have not been adequately assessed. In this paper, we conducted a systematic review and meta-analysis to evaluate the efficacy of Wenjing decoction for the treatment of primary dysmenorrhea.

METHODS

Eight databases were used in our research: the Cochrane Library, the Web of Science, PubMed, EMBASE, the Chinese Biomedical Literature Database (CBM), the Chinese National Knowledge Infrastructure (CNKI), the Chinese Scientific Journal Database, and the Wan-fang Database. The following search terms were used: (Wenjing decoction OR Wenjing formula OR Wenjing tang) AND (primary dysmenorrhea OR dysmenorrhea OR painful menstruation) AND (randomized controlled trial). No language limitation was used.

RESULTS

A total of 18 studies, including 1736 patients, were included in the meta-analysis. Wenjing decoction was shown to be significantly better than nonsteroidal anti-inflammatory drugs for the improvement of primary dysmenorrhea according to the clinical effective rate (RR 1.41, 95% CI 1.24-1.61), the visual analogue scale (MD -1.77, 95% CI -2.69 to -0.84), and the pain scale for dysmenorrhea (MD -1.81, 95% CI -2.41 to -1.22).

CONCLUSIONS

The results supported the clinical use of Wenjing decoction for the treatment of primary dysmenorrhea. However, the quality of the evidence for this finding was low due to a high risk of bias in the included studies. Therefore, well-designed randomized controlled trials are still needed to further evaluate the efficacy of Wenjing decoction for the treatment of primary dysmenorrhea.

The role of treatment timing and mode of stimulation in the treatment of primary dysmenorrhea with acupuncture: An exploratory randomised controlled trial

OBJECTIVES

We examined the effect of changing treatment timing and the use of manual, electro acupuncture on the symptoms of primary dysmenorrhea.

METHODS

A randomised controlled trial was performed with four arms, low frequency manual acupuncture (LF-MA), high frequency manual acupuncture (HF-MA), low frequency electro acupuncture (LF-EA) and high frequency electro acupuncture (HF-EA). A manualised trial protocol was used to allow differentiation and individualized treatment over three months. A total of 74 women were randomly assigned to one of the four groups (LF-MA n = 19, HF-MA n = 18, LF-EA n = 18, HF-EA n = 19). Twelve treatments were performed over three menstrual cycles, either once per week (LF groups) or three times in the week prior to menses (HF groups). All groups received a treatment in the first 48 hours of menses. The primary outcome was the reduction in peak menstrual pain at 12 months from trial entry.

RESULTS

During the treatment period and nine month follow-up all groups showed statistically significant (p < .001) reductions in peak and average menstrual pain compared to baseline but there were no differences between groups (p > 0.05). Health related quality of life increased significantly in six domains in groups having high frequency of treatment compared to two domains in low frequency groups. Manual acupuncture groups required less analgesic medication than electro-acupuncture groups (p = 0.02). HF-MA was most effective in reducing secondary menstrual symptoms compared to both-EA groups (p<0.05).

CONCLUSION

Acupuncture treatment reduced menstrual pain intensity and duration after three months of treatment and this was sustained for up to one year after trial entry. The effect of changing mode of stimulation or frequency of treatment on menstrual pain was not significant. This may be due to a lack of power. The role of acupuncture stimulation on menstrual pain needs to be investigated in appropriately powered randomised controlled trials.

Treating primary dysmenorrhoea with acupuncture: a narrative review of the relationship between acupuncture 'dose' and menstrual pain outcomes

OBJECTIVE

A number of randomised controlled trials have been performed to determine the effectiveness or efficacy of acupuncture in primary dysmenorrhoea. The objective of this review was to explore the relationship between the 'dose' of the acupuncture intervention and menstrual pain outcomes.

METHODS

Eight databases were systematically searched for trials examining penetrating body acupuncture for primary dysmenorrhoea published in English up to September 2015. Dose components for each trial were extracted, assessed by the two authors and categorised by neurophysiological dose (number of needles, retention time and mode of stimulation), cumulative dose (total number and frequency of treatments), needle location and treatment timing.

RESULTS

Eleven trials were included. Components of acupuncture dose were well reported across all trials. The relationship between needle location and menstrual pain demonstrated conflicting results. Treatment before the menses appeared to produce greater reductions in pain than treatment starting at the onset of menses. A single needle during menses may provide greater pain reduction compared to multiple needles. Conversely, multiple needles before menses were superior to a single needle. Electroacupuncture may provide more rapid pain reduction compared to manual acupuncture but may not have a significantly different effect on overall menstrual pain.

CONCLUSIONS

There appear to be relationships between treatment timing and mode of needle stimulation, and menstrual pain outcomes. Needle location, number of needles used and frequency of treatment show clear dose-response relationships with menstrual pain outcomes. Current research is insufficient to make definitive clinical recommendations regarding optimum dose parameters for treating primary dysmenorrhoea.

Complementary and alternative treatments for primary dysmenorrhea in adolescents

Primary dysmenorrhea is the most common gynecologic complaint among adolescents. Conventional treatments include nonsteroidal anti-inflammatory drugs and hormonal contraceptives, but complementary and alternative medicine is a growing area of interest. As patients seek such treatments, pediatric nurse practitioners should be aware of these options to offer the best advice to patients.

Predicting painful or difficult intrauterine device insertion in nulligravid women

OBJECTIVE

To assess the relationship of preinsertion vaginal ultrasound assessment and menstrual and gynecologic history as predictors of difficult or painful intrauterine device insertion in nulligravid women.

METHODS

Nulligravid women seeking contraception were invited to participate in this nonrandomized study and given the choice between the levonorgestrel-releasing intrauterine system or a copper-releasing intrauterine device. All 165 enrolled women were interviewed and a pelvic examination, including vaginal ultrasonography, was performed before insertion. Insertion difficulties and pain intensity were recorded and assessed against uterine measurements and background characteristics.

RESULTS

Most insertions were assessed as easy (n=144 [89.4%]) and only two (1.2%) failed. Most women had uterine measurements smaller than the studied devices. Odds for difficulties at insertion decreased with every increasing millimeter in total uterine length (odds ratio [OR] 0.86, 95% confidence interval [CI] 0.78-0.96, P=.006) and cervical length (OR 0.85, 95% CI 0.74-0.97, P=.02) and similarly with every decreasing degree of (straighter) flexion angle (OR 0.96, 95% CI 0.94-0.99, P=.005). No absolute threshold measurements could be determined. Still, the majority of insertions in small and flexed uteri were uneventful. Severe insertion pain was common (n=94 [58.4%]). Severe dysmenorrhea was the only predictor of insertion pain (OR 8.16 95% CI 2.56-26.02, P<.001).

CONCLUSION

Ultrasonographic evaluation does not give additional information compared with clinical pelvic examination and sound measure. Although smaller uterine length measurements and steeper flexion angle more often predicted difficulties, the majority of insertions were uneventful in women with small measures. Dysmenorrhea was the only predictor of pain.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, www.clinicaltrials.gov, NCT01685164.

LEVEL OF EVIDENCE

II.

Evaluation of the efficacy of Fructus agni casti in women with severe primary dysmenorrhea: a prospective comparative Doppler study

AIM

The aim of this case-control study was to compare the efficacy of ethinyl estradiol/drospirenone and Fructus agni casti in women with severe primary dysmenorrhea measuring uterine artery blood flow via Doppler ultrasonography.

METHODS

A total of 60 women with severe primary dysmenorrhea and 30 healthy women (control) were included in this study. Thirty patients were treated with ethinyl estradiol 0.03 mg/drospirenone (group 1) and another 30 were treated with Fructus agni casti (group 2) during three menstrual cycles. Before and at the end of third month of therapy visual analog scale (VAS) scores, pulsatility index (PI), resistance index (RI) of uterine artery were recorded before and after receiving therapy on the first day of the menstrual cycle.

RESULTS

Mean PI and RI values in patients with severe primary dysmenorrhea were significantly higher than in the control groups on the first day of the menstrual cycle (P < 0.0001). Mean PI and RI values were significantly lower after the treatment in both groups compared to before values (P < 0.001 for both). After using the drugs for three menstrual cycles, VAS scores were significantly dropped in both groups compared to before treatment values (P < 0.0001 for both); however, there were no significant differences in terms of Doppler findings between group 1 and 2.

CONCLUSION

The effectiveness of Fructus agni casti was similar to that of ethinyl estradiol/drospirenone in patients with primary dysmenorrhea.