Type 3 fibroids are a special subtype of IM fibroids that are most likely to affect pregnancy outcomes of assisted reproductive techniques. They can affect endometrial receptivity, the hormonal milieu, and alter endometrial development that may be underlying causes of primary or secondary infertility . Hysteroscopic resection is a treatment for type 3 fibroids, but there has been no specific study of its efficacy to date. Moreover, we did not know whether hysteroscopic myomectomy could improve fertility and IVF-ICSI outcomes of infertile women with type 3 fibroids. Our study focused on the effectiveness of hysteroscopic resection of type 3 fibroids on pregnancy outcomes in infertile women.
The current study demonstrates that hysteroscopic resection, as a treatment for type 3 fibroids, can improve cumulative live birth rates in patients with type 3 fibroids undergoing IVF-ICSI, and significantly improve the transfer time to live birth for patients after surgery. Although the cumulative live birth rate between Surgery and Non-surgery group were not statistically significant, rates for the Surgery group were higher than Non-surgery group (62.1% vs. 55.3%) and there was a statistical difference between Non-surgery group and control group (55.3% vs. 79.6%). However, there was no statistical difference between the control group and surgery group (62.1% vs. 79.6%). Statistical differences were found in the average transfer times to live birth among the three groups; the Non-surgery group was significantly higher than the other two groups. Hysteroscopic myomectomy can improve the time to live birth to a certain extent, although, before and after hysteroscopic myomectomy, the average transfer times to live births, the cumulative clinical pregnancy rate and cumulative live birth rate were not statistically different. But compared with the two groups, the average transfer times to live birth after operation were less than those of the preoperative group [1(1,1) vs. 2(1,3)]; the cumulative clinical pregnancy rate and the cumulative live birth rate were higher than the preoperative group at 42.9% vs. 28.6% and 42.9% vs. 14.3%. Therefore, in a sense, hysteroscopic resection can improve the clinical pregnancy rate and live birth rate of patients with type 3 fibroids, and shorten the time to live birth. In addition, three postoperative patients were followed up who obtained a spontaneous pregnancy and a live birth.
In our hospital and unit, TVS and hysteroscopy are performed by experienced clinicians, so the reliability of the data can be guaranteed. In this study, the length of time between diagnosis and surgery was quite short. On the other hand we let each patient go through two menstrual cycles before returning since the endometrial recovery time after hysteroscopy is 6–8 weeks .
In this study, we used a series of matching and exclusion criteria to keep interference factors to a minimum. As it is known that COS protocols can affect IVF success , there was no statistically significant difference in ovarian stimulation protocols among the three groups. As previously reported in the literature , type 3 fibroids with SD or TD > 2.0 cm can significantly decrease the live birth rate after IVF-ICSI, so we choose patients with SD or TD fibroids > 2.0 cm and single fibroids < 5.0 cm as the research subjects. In order to select the appropriate research population and exclude the influence of other infertility factors, we selected patients who were treated with IVF only because of fallopian tube factors as the control group. Age was used as the screening index, so the ovarian function of the control group was better than the other two groups. Because of this, the number of MII oocytes retrieved and the Day 3 serum FSH values of control group were significantly different from those of the other two groups.
The principal limitation of this study was the small number of patients, which led to a low statistical power. However, there are not many women with type 3 myoma who undergo hysteroscopic myomectomy. Sensitivity analysis suggests that the estimated value of the included study was basically within the confidence interval of the total effect size, that is to say, the result was stable. Selection bias in data analysis is inevitable in a retrospective study. In addition, some patients underwent surgery after COS, and the stimulation of COS on fibroids cannot be ruled out. Therefore, large cases of randomized controlled long-term observational research are suggested in the future.
To the best of our knowledge, this is the first independent study to address the impact of hysteroscopic resection of type 3 fibroids on the pregnancy outcomes of infertile women. Furthermore, this study shows the necessity of a clinical consultation with infertile patients with type 3 fibroids with SD or TD > 2.0 cm regarding the need for hysteroscopic myomectomy. One of the important advantages of the present study was the use of multiple matching criteria and randomization principles to minimize the clinical heterogeneity of the included patients.