The efficacy of oxytocin gel in postmenopausal women with vaginal atrophy: an updated systematic review and meta-analysis

BACKGROUND

Genitourinary syndrome of menopause (GSM) is a common and disturbing issue in the postmenopausal period. Unlike vasomotor symptoms, it has a progressive trend. Our study aims to evaluate the efficacy and safety of oxytocin gel versus placebo gel in postmenopausal women with GSM.

METHODS

A systematic review and meta-analysis synthesizing randomized controlled trials (RCTs) from Web of Science, SCOPUS, PubMed, and Cochrane Central Register of Controlled Trials databases on January 18, 2023. Keywords such as "oxytocin," "intravaginal," "vaginal," "atrophic," and "atrophy" were used. We used Review Manager (RevMan) version 5.4 in our analysis. We used the risk ratio (RR) for dichotomous outcomes and the mean difference (MD) for continuous outcomes; both were presented with the corresponding 95% confidence interval (CI) and were calculated with the Mantel-Haenszel or inverse variance statistical method. Cochrane's Q test and the I2 statistic were used as measures of statistical inconsistency and heterogeneity. The Cochrane Risk of Bias Tool for RCTs was used for the quality assessment of the included studies.

RESULTS

Seven studies with 631 patients were included. Regarding the maturation index, there was a statistically insignificant increase in the oxytocin arm (MD = 12.34, 95% CI (-12.52-37.19), P = 0.33). Clinically assessed vaginal atrophy showed a statistically significant reduction in the oxytocin group (RR = 0.32, 95% CI (0.23 - 0.10), P < 0.00001). For dyspareunia, vaginal pH, and histological evaluation of vaginal atrophy, there was a statistically insignificant difference between the two groups (RR = 1.02, 95% CI (0.82-1.27), P = 0.84), (MD = -0.74, 95% CI (-1.58-0.10), P = 0.08), and (MD = -0.38, 95% CI (-0.82-0.06), P = 0.09), respectively. There was no significant difference in the safety profile between the two groups as measured by endometrial thickness (MD = 0.00, 95% CI (-0.23-0.23), P = 0.99).

CONCLUSIONS

Although oxytocin has been proposed as a viable alternative to estrogen in the treatment of GSM, our findings show the opposite. Larger, high-quality RCTs are needed to confirm or refute our results.

TRIAL REGISTRATION

PROSPERO registration number CRD42022334357.

Oxytocin versus a combination of tranexamic acid and ethamsylate in reducing intraoperative bleeding during abdominal myomectomy: a randomized clinical trial

OBJECTIVE

Myomectomy is the preferred surgical approach to manage uterine fibroids. However, uterine fibroids are highly vascular tumors and, consequently, extremely susceptible to problems from myomectomy-related hemorrhage. Hence, we aim to compare oxytocin efficacy and safety profile versus tranexamic acid (TA) with ethamsylate for reducing bleeding during myomectomy.

METHODS

This randomized, double-blinded multicenter study was performed between 20th August 2020 and 20th October 2020 at El-Galaa Teaching Hospital, El Hussein University Hospital, Al-Azhar University Hospitals of Assiut, and Al-Azhar University Hospitals of Damietta. One hundred and eighty patients were enrolled and divided into three groups: group (1) received an injection of 30 IU of oxytocin in 500 ml of normal saline; group (2) received injections of 1 g of TA, 250 mg of Ethamsylate, and 110 ml of normal saline IV; and group (3) received an injection of 110 ml of normal saline IV just before surgical incision.

RESULTS

In 180 premenopausal women, oxytocin and TA with ethamsylate had no significant value in lowering intraoperative blood loss compared with the placebo for abdominal myomectomy (666.25 ± 183.03, 630.72 ± 145.83, and 646.67 ± 168.92, respectively (P = 0.506)). Non-significant trends were observed for a reduction in operation time (P = 0.760), intra/postoperative blood transfusion (P = 0.624), hospital stay (P = 0.986), postoperative fever (P = 0.659), and wound infection (P = 1).

CONCLUSION

Oxytocin and TA with ethamsylate had no significant value in lowering intraoperative blood loss compared with the placebo for abdominal myomectomy which opens a new question about the role of the use of the hemostatic drug during myomectomy especially in centers with limited resources and had higher rates.

TRIAL REGISTRATION

The study was registered on Pan African Clinical Trials Registry with the following number: PACTR202008739887429 and was approved on 24/08/2020.

Comparative study between oxytocin and combination of tranexamic acid and ethamsylate in reducing intra-operative bleeding during emergency and elective cesarean section after 38 weeks of normal pregnancy

OBJECTIVE

Cesarean Section (CS) is associated with an increased risk of hemorrhage. Many drugs are used to decrease this risk. We aim to compare the combination of ethamsylate and tranexamic acid, oxytocin, and placebo in women undergoing CS.

METHODS

We conducted a double-blinded, randomized, placebo-controlled trial between October and December 2020 in four university hospitals in Egypt. The study included all pregnant women in labor without any complications who accepted to participate in the study between October and December 2020. The participants were divided into three groups. The subjects were randomly allocated to receive either oxytocin (30 IU in 500 ml normal saline during cesarean section), combined one gram of tranexamic acid with 250 mg of ethamsylate once before skin incision, or distilled water. Our main outcome was the amount of blood loss during the operation. The secondary outcomes were the need for blood transfusion, hemoglobin and hematocrit changes, hospital stay, operative complications, and the need for a hysterectomy. The one-way ANCOVA test was used to compare the quantitative variables between the three groups while the Chi-square test was used to compare the qualitative variables. Post hoc analysis then was performed to compare the difference between every two groups regarding the quantitative variables.

RESULTS

Our study included 300 patients who were divided equally into three groups. Tranexamic acid with ethamsylate showed the least intra-operative blood loss (605.34 ± 158.8 ml) compared to oxytocin (625.26 ± 144.06) and placebo (669.73 ± 170.69), P = 0.015. In post hoc analysis, only tranexamic acid with ethamsylate was effective in decreasing the blood loss compared to placebo (P = 0.013); however, oxytocin did not reduce blood loss compared to saline (P = 0.211) nor to tranexamic acid with ethamsylate (P = 1). Other outcomes and CS complications showed no significant difference between the three groups except for post-operative thrombosis which was significantly higher in the tranexamic and ethamsylate group, P < 0.00001 and the need for a hysterectomy which was significantly increased in the placebo group, P = 0.017.

CONCLUSION

The combination of tranexamic acid and ethamsylate was significantly associated with the least amount of blood loss. However, in pairwise comparisons, only tranexamic acid with ethamsylate was significantly better than saline but not with oxytocin. Both oxytocin and tranexamic acid with ethamsylate were equally effective in reducing intra-operative blood loss and the risk of hysterectomy; however, tranexamic acid with ethamsylate increased the risk of thrombotic events. Further research with a larger number of participants is needed.

TRIAL REGISTRATION

The study was registered on Pan African Clinical Trials Registry with the following number: PACTR202009736186159 and was approved on 04/09/2020.