Investigation Of The Effect Of High Intensity Focused Ultrasound Treatment On Pregnancy In Patients With Uterine Fibroids

Uterine fibroids are the most common benign tumors in female reproductive system.The prevalence of uterine fibroids is generally reported as 20% ～ 50% in childbearing age women,and up to 70% in women over 35 years.The etiology and pathogenesis of uterine fibroids are still unclear,which may be related to genetic,hormone levels and environmental factors.Uterine fibroids may lead to symptoms,such as heavy and prolonged menstrual flow,urinary frequency,and anemia.Uterine fibroids can lead to infertility because of the uterine anatomical structure changes,abnormal uterine contraction and peristalsis,and reduced uterine receptivity.It is reported that 5%～10% of infertile patients are related to uterine fibroids.Uterine fibroids can also increase the risk of abnormal fetal position,miscarriage,premature delivery,dystocia and postpartum hemorrhage.Many studies showed that the pregnancy rate of patients with uterine fibroids is significantly lower than that of normal women.At present,we are facing the severe situation of declining birth rate.Therefore,it is particularly important to choose appropriate treatment for patients with uterine fibroids who wish to conceive.The conventional treatments of uterine fibroids included medicine and surgery.Administration of medicine can effectively control the symptoms related to uterine fibroids,but withdrawal often leads to the recurrence of symptoms.Surgical treatments included hysterectomy and myomectomy.Laparotomy has been gradually replaced by laparoscopic surgery due to its large amount of bleeding and damage.Myomectomy is the treatment of choice for patients who wish to conceive.Although myomectomy retains their uterus,the incidence of postoperative adhesion is as high as 34%,the recurrence is reported as 10% in 2 years,and the patients need to wait for at least 1 to 2 years for pregnancy after myomectomy.The probability of uterine rupture in the middle and late pregnancy is around 0.23% ～ 1%after myomectomy.Uterine artery embolization(UAE)has been used in the treatment for uterine fibroids,but the risk of puncture site hematoma,pelvic ischemic pain,ovarian function failure,uterine necrosis caused by miss embolization limited the utility in clinical practice.With the changes of the national family plan policy and the improvement of people’s requirements for the quality of life,the treatment strategies for patients with uterine fibroids who have fertility intention are also changing accordingly.As a non-invasive treatment,high intensity focused ultrasound(HIFU)has been widely used in the treatment of uterine fibroids.The main mechanism of this therapy is thermal effect,mechanical effect,cavitation effect and sonochemical reaction by focusing ultrasound to make the temperature increase to 60～100 ℃ in the target tissue.The coagulation necrosis occurred in the treated area,and the tumor nourishing blood vessels were also destroyed,then the treated uterine fibroids were shrank or disappeared,and the symptoms relieved.At present,many studies have demonstrated that HIFU can achieve similar therapeutic effects comparable to gynecological surgery through real-time monitoring system.With the widely application of HIFU technology in clinical practice,some experts and scholars put forward that HIFU could cause coagulation necrosis of uterine fibroids.Does it affect normal uterine smooth muscle? Does it affect the patient’s pregnancy? Does it increase the risk of pregnancy complications?Currently,the effect of HIFU on pregnancy and pregnancy outcomes is still uncertain because of the limited papers with small sample size.Wu et al.analyzed the pregnancy outcomes of 35 patients with uterine fibroids after HIFU treatment,their results showed that HIFU did not increase the risk of complications during pregnancy and delivery.The conceive time was generally 12～24 months after HIFU.Lumsden et al.also showed that HIFU is a safe and effective way for patients with pregnancy desire.Qin et al.retrospectively reviewed 435 patients who received HIFU treatment,24 patients had pregnancy one year after HIFU,17 of them had abortion because they had no desire to have children,and the remaining 7 patients delivered healthy babies at terms,of which 6 patients underwent cesarean section due to social factors in 5 patients,and 1 patient was suspected of fetal distress.No pelvic adhesions were found during cesarean section.Froelingn et al.reported that 25% of patients with uterine fibroids treated by HIFU had successful pregnancy,and 70% of them had vaginal delivery.Therefore,based on the clinical data,this study hopes to explore the influence of high-intensity focused ultrasound on fertility and perinatal outcomes of patients with uterine fibroids through retrospective analysis and prospective clinical control study.So as to provide some reference for patients with uterine fibroids who have fertility requirements.At present,the etiology and mechanism of uterine fibroids are unclear.In the past,it was thought that the over-expression of estrogen and progesterone receptors in uterine fibroid tissue could promote the growth of uterine fibroid,and estrogen and progesterone receptor antagonists can significantly inhibit the growth of uterine fibroids and improve symptoms.Several studies have analyzed the correlation between the expression of estrogen and progesterone receptors and the recurrence rate of uterine fibroids after myomectomy.It is found that the high expression of estrogen and progesterone receptors resulted in the higher recurrence rate of uterine fibroids.Qin et al.discussed the mechanism of residual tissue of isolated uterine fibroids after HIFU ablation,and found that HIFU ablation did not change the expression of estrogen and progesterone receptors at different sites outside the target area.By comparing the expression of cytokines in myometrium of patients with uterine fibroid and the patients without uterine fibroids,a study concluded that the expression pattern related to chronic inflammation in LPCs may play a role in the increase risk of adverse obstetric outcomes(infertility,spontaneous miscarriage,and premature birth).However,no study has explored the differences of estrogen and progesterone receptor expression in target lesion tissue,peripheral muscular tissue and new fibroids after HIFU treatment.Metabonomics has attracted much attention in recent years.When the body is stimulated by external stressors,it will produce multifaceted responses,thus cause corresponding changes in metabolism level.Metabolomics can directly reflect the physiological activities of cells and is a useful tool for identifying biomarkers and revealing pathogenic mechanisms.Chromatography-mass spectrometry(GC-MS)has become one of the main research techniques in metabolomics because of its advantages of high resolution,throughput and sensitivity.Metabolomics based on GC-MS has advantages in the detection of metabolites such as glycolysis,Tricarboxylic Acid cycle(TCA),amino acids and organic acids.In addition,compared with other metabolomics technologies,GC-MS technology is more mature and more stable.The classic Warburg effect proposed that the growth rate of tumor cells was much higher than that of normal cells because of the difference in energy sources,and the occurrence and development of tumor was related to abnormal glycolysis metabolism.Under the condition of adequate oxygen,the cells absorb glucose to generate lactic acid,which activates related signaling pathways and changes the tumor micro-environment.Many proteins regulating metabolism can regulate apoptosis,and some proteins regulating apoptosis also play messenger role in metabolic pathway.Some basic studies have found that lipids,very low density lipoprotein,lactate and threonine were significantly increased in the uterine fibroid model group through Wistar rat uterine fibroid model and metabonomics method based on NMR-spectrum,indicating that uterine fibroids can cause metabolic changes.In addition to coagulative necrosis of the focal tissues,will HIFU treatment lead to changes in the micro-environment and metabolic characteristics of local tissues?Therefore,with the increasing application of HIFU in the treatment of uterine fibroids,more and more experts and scholars pay attention to the impact of HIFU on pregnancy.Some studies have shown that HIFU does not affect pregnancy,but some case reports showed that HIFU may lead to uterine rupture.Its advantages and disadvantages are still controversial.Based on the above clinical questions,this study intends to explore and verify whether HIFU has an impact on pregnancy rate and perinatal outcome through retrospective and prospective clinical studies;At the same time,we explored the possible effect of HIFU on pregnancy and its possible mechanism through estrogen and progesterone receptor expression and metabolomic changes.ObjectiveTo retrospectively analyze the pelvic adhesions and the perinatal outcomes of patients with uterine fibroids treated by HIFU.To analyze the pregnancy and neonatal related outcomes of patients with uterine fibroids treated by HIFU through prospective concurrent control study.To analyze the expression of ER,PR in in the treated or non-treated tissue of the uterine fibroids.To explore the metabolites and metabolic pathways affected by HIFU in uterine fibroids through GC-MS.Method1.Analysis of pelvic adhesions in patients with uterine fibroids after HIFU treatment by Retrospective clinical study(single center).The patients who underwent hysterectomy,myomectomy and cesarean section in our Hospital from October 2010 to March 2020 were selected and divided into HIFU group and control group according to the inclusion and exclusion criteria.The age,menstrual history,pregnancy history,operation history,main clinical symptoms,location,classification,size and number of myoma were collected.The pelvic adhesions of the subjects were analyzed by pelvic adhesions score system,and the ablation time,ablation power and target myoma ablation rate were compared.2.Analysis of the pregnancy outcomes in patients with uterine fibroids treated by HIFU through Retrospective clinical study(double centers).Patients with uterine fibroids treated by HIFU were collected from October2010 to October 2017 in two Haifu Central(HIFU Hospital and Suining central hospital)according to the inclusion and exclusion criteria.The age,menstrual history,pregnancy and childbirth history,main clinical symptoms,location,classification,size and number of fibroids were recorded before operation.And the sonication time,sonication power,non-perfusion volume ratio(NPVr),reduction rate,target fibroid location,energy efficiency factor(EEF),treatment time and treatment dose of HIFU were collected.3.Through the prospective concurrent control study to analysis the perinatal outcomes of patients with uterine fibroids in HIFU treatment group and non-treatment group.Collect the patients with a single uterine fibroid treated by HIFU according to the inclusion and exclusion criteria from June 2017 to June 2019 in our hospital.And the patients with uterine fibroids,but without intervention were divided into control group.Menstrual volume,birth history,BMI,uterine volume and energy efficiency index(ablation time,ablation power,target myoma ablation rate,reduction rate),pregnancy complications during treatment were collected.4.From June 2019 to June 2020,uterine fibroids patients who were treated by HIFU in the past underwent hysterectomy in our hospital(HIFU group),and the patients who had hysterectomy in our hospital at the same time were set as control group.In the HIFU group,12 patients(endometrial tissue,myoma tissue after HIFU treatment,new myoma tissue and normal myometrial tissue)and 48 specimens were collected;in the control group,5 patients(new myoma tissue,myometrial tissue and endometrial tissue)and 15 specimens were collected.Through immunohistochemistry analysis the immunohistochemical characteristics of uterine fibroids treated with and without HIFU.Through GC-MS spectrometer to test the metabolomics features of uterine fibroid treated with and without HIFU.Metabo Analyst(5.0)analysis the PLS-DA,Me V,biomaker and metabolic pathway.Results1.There were 42 cases of pelvic adhesions in HIFU group(n=96,43.75%),619 cases in control group(n=1713,36.14%).There was no significant difference in the location and degree of adhesion between the two groups.Excessive total energy input of HIFU treatment(Median=330666J),long ablation time(Median=876S)of treatment and too many times of delivery(>2 times)can increase the incidence of pelvic adhesions,while low energy efficiency factor(Median=2.25)can reduce the incidence of pelvic adhesions(P<0.05).2.There were 6341 patients with uterine fibroids treated by HIFU in Suining Central Hospital and Chongqing Haifu Hospital,including 1268 cases with fertility requirements,189 cases of pregnancy(20 cases had abortion,164 cases had delivery,3 cases had ectopic pregnancy,2 cases had incision pregnancy),and 5073 cases without pregnancy requirement,including 52 cases of pregnancy(50 cases of induced abortion,2 cases of arrested embryo).The rate of pregnancy and delivery in patients who had fertility requirements was 14.9% and 86.8%,respectively.There were significant differences in the volume of uterine fibroids,NPV ratio,EEF,sonication time,treatment time and treatment dose between the pregnant group and the non-pregnant group after HIFU treatment.Total energy delivered was negatively correlated with pregnancy rate.3.80 patients in HIFU group and control group(without treatment)were included in the study,and the lost follow-up rates were 5% and13.75% respectively.The difference was not statistically significant in follow-up lost rate.There was no significant difference in demographic characteristics,menstrual history,educational level,times of pregnancy and childbirth,BMI,distribution and type of uterine fibroids between the two groups.There were 48 cases in HIFU group and 18 cases in control group conceived.The average pregnancy time of HIFU group was shorter than that of control group.There was a significant difference in the distribution of pregnancy time between the two groups,and the HIFU group was concentrated in 7 ～ 18 months after operation.There were significant differences in delivery rate and pregnancy rate between the two groups.The pregnancy rate and delivery rate of HIFU group were higher than those of the control group.The difference of postpartum hemorrhage between HIFU pregnancy group and control group was statistically significant.There was no statistical significance in the incidence of hypertensive disorder complicating pregnancy,intrahepatic cholestasis of pregnancy,gestational diabetes mellitus,premature rupture of membranes,premature delivery,hypothyroidism,cephalopelvic disproportion and placenta previa between the two groups.The fetal distress,placental abruption and uterine rupture were not observed in both groups.4.After HIFU treatment,the expression of ER and PR in uterine fibroid tissue was not significantly different from that in normal myometrium tissue and endometrial tissue,but significantly lower than that in tissue of recurrent fibroids,the difference was statistically significant.HIFU treatment did not affect the expression of ER and PR in non-target tissue.HIFU treatment did not increase the overexpression of ER and PR in non-target tissues and its recurrence risk of fibroids.5.There were differences in metabolite spectrum between HIFU group and control group,which were reflected in fatty acid metabolism intermediates and their derivatives(such as acetamide,γ-ketoglutarate monoamide,etc.)and TCA intermediates and their derivatives(such as malic acid,fumaric acid,niacin,etc.).and there is significant difference in fatty acid oxidation metabolism intermediates and derivatives.HIFU can up-regulate the aerobic oxidation process of fibroids by affecting the fatty acid metabolic pathway in mitochondria,and further promote the oxidative metabolism of tricarboxylic acid cycle.Conclusion1.The average total treatment energy of HIFU over 330666 J and the average ablation time over 876 seconds may increase the risk of pelvic adhesions.However,the average energy efficiency factor less than 2.25 may reduce the incidence of adhesion.Therefore,energy input,ablation time,energy efficiency factors and other factors should be taken into consideration to make a treatment plan for women with uterine fibroids with fertility intention.2.HIFU treatment can shorten the pregnancy preparation period of patients with uterine fibroids who are willing to give birth and reduce the incidence of postpartum hemorrhage in pregnant women with uterine fibroids.No severe complications such as uterine rupture,fetal intrauterine distress and placental abruption were observed.The lower mean total treatment energy of HIFU(less than 321894J)and shorter mean sonication time(less than 733 seconds)may increase pregnancy rate.3.HIFU treatment can reduce the expression of ER and PR,control the growth of fibroids during pregnancy and reduce pregnancy complications.4.HIFU can restore the aerobic oxidation capacity of fibroid tissue microenvironment.