劉林麗+齊碧如+黃勉+林舟+劉欣茹+林珺
[摘要] 目的 觀察及比較不同時(shí)期促排卵方案對(duì)POR患者的臨床結(jié)局。 方法 回顧性分析37例卵巢低反應(yīng)患者第1周期行卵泡期促排卵失敗后,第2周期改行黃體期促排卵,與109例行卵泡期微刺激促排卵患者對(duì)比,比較兩組促排卵方案的胚胎發(fā)育及妊娠結(jié)局情況。 結(jié)果 黃體期促排卵組共獲卵120枚,卵泡期促排卵組獲卵379枚,兩組平均獲卵數(shù)[(4.37±1.07) vs (4.79±1.12)]無(wú)統(tǒng)計(jì)學(xué)差異(P>0.05)。但黃體期促排卵組的正常受精率[(93.3%) vs (73.4%)]、優(yōu)質(zhì)胚胎率[(88.7%) vs (78.7%)]及臨床妊娠率[(27.0%) vs (13.4%)]均顯著高于卵泡期促排卵組,差異有統(tǒng)計(jì)學(xué)意義(P<0.05)。 結(jié)論 黃體期促排卵是可行的,不失為卵巢反應(yīng)低下患者促排卵的新思路。
[關(guān)鍵詞] 黃體期促排卵;卵泡期促排卵;微刺激;卵巢低反應(yīng);妊娠結(jié)局
[中圖分類號(hào)] R711.75 [文獻(xiàn)標(biāo)識(shí)碼] B [文章編號(hào)] 1673-9701(2017)08-0062-04
[Abstract] Objective To observe and compare the clinical outcome of ovariectomized patients in different periods. Methods 37 poor ovarian response patients were retrospectively analyzed. The patients switched to undergo the promotion ovulation at luteal phase in the second cycle after the failure of promoting ovulation at follicular phase. And the patients were compared with 109 cases undergoing micro-stimulation to promote ovulation. The embryo development and pregnancy outcome between the two ovulation promotion programs were compared. Results There were 120 ova in the luteal-phase ovulation promotion group and 379 ova in the follicular-period ovulation promotion group. There was no statistical difference in the average number of obtained ova between the two groups[(4.37±1.07) vs (4.79±1.12)]. Normal fertilization rate[(93.3%)vs.(73.4%)], good quality embryo rate[(88.7%) vs (78.7%)]and clinical pregnancy rate[(27.0%) vs (13.4%)] in the luteal-phase ovulation promotion group was higher than that of the follicular period ovulation promotion group, respectively. And the differences were statistically significant(P<0.05). Conclusion Promoting ovulation at luteal-phase is feasible, which is a new idea for ovulation induction in patients with low ovarian response.
[Key words] Ovulation promotion at luteal-phase; Ovulation promotion at follicular period; Micro-stimulation; Poor ovarian response; Pregnancy outcome
卵巢低反應(yīng)(poor ovarian response,POR)主要表現(xiàn)為促排卵獲卵數(shù)少,卵子質(zhì)量下降,臨床妊娠率低等。探索合理個(gè)體化的促排卵方案以提高卵子質(zhì)量,改善妊娠結(jié)局是目前的一大難題。過(guò)去我們認(rèn)為,在卵泡早期一批卵泡開(kāi)始募集發(fā)育,最終只有一個(gè)優(yōu)勢(shì)卵泡排卵而其他卵泡發(fā)生閉鎖凋亡,這成為卵泡期促排卵的理論基礎(chǔ)[1,2]。直到2003年,有學(xué)者提出,正常月經(jīng)周期中存在2~3個(gè)卵泡募集波的理論,利用排卵后FSH峰或者外源FSH/CC的作用,使黃體期卵泡募集繼續(xù)發(fā)育為成熟卵泡而供取卵使用,這為黃體期促排卵方案奠定了理論基礎(chǔ)[3]。據(jù)有關(guān)報(bào)道,某卵巢低反應(yīng)患者多次常規(guī)促排卵失敗后,經(jīng)一次黃體期促排卵后獲得臨床妊娠,本文將進(jìn)一步比較黃體期促排卵與卵泡期促排卵對(duì)卵巢低反應(yīng)患者的臨床結(jié)局的影響。
1 資料與方法
1.1 一般資料
根據(jù)歐洲人類生殖與胚胎學(xué)會(huì)(ESHRE)就卵巢低反應(yīng)診斷在博洛尼亞達(dá)成的共識(shí),以下3條至少符合2條者定義為POR:(1)高齡(妻40歲)或具備低反應(yīng)的任何危險(xiǎn)因素;(2)前次低反應(yīng)(常規(guī)刺激促排卵獲卵≤3個(gè)卵子);(3)一個(gè)異常卵巢儲(chǔ)備實(shí)驗(yàn)結(jié)果(如AFC<5~7個(gè),或抗苗勒管撤素(AMH)<1.6~3.5 nmol/L)[4]。本研究根據(jù)以上標(biāo)準(zhǔn),回顧性分析2015年1月~2016年6月146例卵巢低反應(yīng)患者,其中37例均為前一周期行卵泡期促排卵失敗,本周期采用黃體期促排卵方案,其余109例行卵泡期微刺激方案促排卵。兩組患者一般資料間無(wú)明顯差異(表1)。本研究經(jīng)過(guò)我院生殖醫(yī)學(xué)中心醫(yī)學(xué)倫理委員會(huì)的批準(zhǔn)。
1.2 方法
1.2.1 黃體期促排卵組 自然周期監(jiān)測(cè)卵泡直徑≥18~20 mm,當(dāng)晚注射HCG 10000 U,34~36 h后穿刺取卵,陰道超聲監(jiān)測(cè)卵巢內(nèi)有一個(gè)或者多個(gè)6~12 mm 的小卵泡,當(dāng)日即口服克羅米芬(CC)100 mg/d 直至注射HCG日,根據(jù)卵泡大小、生長(zhǎng)速度及激素水平適時(shí)調(diào)整果納芬(Gn)用量75~150 IU/L,當(dāng)有1個(gè)卵泡直徑≥18~20 mm,或者有2~3個(gè)卵泡直徑≥16 mm,停用Gn,當(dāng)晚注射HCG 10000 U,34~36 h后陰道超聲下取卵,根據(jù)精子質(zhì)量選擇授精方式,卵子體外培養(yǎng)4~6 h后行體外授精(IVF)或行單精子胞漿內(nèi)注射(ICSI)。并行全胚冷凍,待下一周期移植。
1.2.2 卵泡期促排卵組 月經(jīng)第3天起口服來(lái)曲唑(LE)5 mg/d,連用5 d,第8天起隔日或每日肌注Gn150~225 U,同時(shí)嚴(yán)密超聲監(jiān)測(cè)并測(cè)定血清黃體生成素(LH)、雌二醇(E2)及孕酮(P)水平,調(diào)整Gn每日用量。當(dāng)LH及P值較基礎(chǔ)明顯上升,皮下注射短效達(dá)菲林針0.1 mg至注射HCG日。當(dāng)主導(dǎo)卵泡直徑≥16 mm 時(shí)HCG 10000 U肌注,34~36 h后陰道超聲引導(dǎo)下穿刺取卵。根據(jù)精子質(zhì)量選擇授精方式,卵子體外培養(yǎng)4~6 h后行體外授精或行單精子胞漿內(nèi)注射。
1.2.3 體外培養(yǎng)及胚胎評(píng)分 卵子體外授精或行單精子胞漿內(nèi)注射后,18~20 h 后觀察受精情況。將雙原核雙極體者(2PN)視為正常受精。選取正常受精卵繼續(xù)培養(yǎng),每 24 小時(shí)觀察受精卵發(fā)育情況。胚胎的評(píng)分[5]:Ⅰ級(jí):卵裂球大小均勻,形狀規(guī)則,透明帶完整,胞質(zhì)均勻、清晰,胚胎內(nèi)碎片<10%;Ⅱ級(jí):卵裂球大小稍不均勻,形狀略不規(guī)則;胞質(zhì)可有顆?,F(xiàn)象,碎片在10%~20%之間;Ⅲ級(jí):卵裂球大小明顯不均勻,可有明顯的形狀不規(guī)則;胞質(zhì)可有明顯顆?,F(xiàn)象,碎片在21%~50%之間;Ⅳ級(jí):細(xì)胞大小嚴(yán)重不均勻,胞質(zhì)可有嚴(yán)重顆粒現(xiàn)象,碎片在50%以上。d2 4~5個(gè)卵裂球,d3至少6個(gè)卵裂球,評(píng)級(jí)為Ⅰ~Ⅱ級(jí)為優(yōu)質(zhì)胚胎。
1.2.4 胚胎移植 黃體期促排卵患者在下一個(gè)月經(jīng)周期當(dāng)子宮內(nèi)膜厚度>8 mm 時(shí),按照常規(guī)接受凍融胚胎移植。卵泡期促排卵患者在受精后2~3 d 后行胚胎移植。移植后10~14 d 檢測(cè)血清 β-hCG 水平確定是否妊娠,移植后 4~6 周后行 B 超檢查,以 B 超見(jiàn)到宮腔內(nèi)妊娠囊有胎心搏動(dòng)診斷為臨床妊娠。周期取消率指因?yàn)槿÷押鬅o(wú)可移植的胚胎而取消移植。
1.3統(tǒng)計(jì)學(xué)方法
應(yīng)用SPSS 19.0統(tǒng)計(jì)學(xué)軟件,計(jì)量資料用(x±s)表示,采用t檢驗(yàn),計(jì)數(shù)資料用率表示,采用χ2檢驗(yàn),P<0.05 為差異有統(tǒng)計(jì)學(xué)意義。
2 結(jié)果
2.1 兩組患者一般資料
兩組患者年齡、不孕年限、體重指數(shù)、基礎(chǔ)FSH值及竇卵泡數(shù)、血清AMH值等指標(biāo)間比較,差異無(wú)統(tǒng)計(jì)學(xué)意義(P均>0.05),具有可比性。見(jiàn)表1。
2.2 胚胎發(fā)育及妊娠結(jié)局
黃體期促排卵組,Gn用量及Gn刺激天數(shù)少于卵泡期促排卵組,但差異無(wú)統(tǒng)計(jì)學(xué)意義。HCG注射日抽取血清激素發(fā)現(xiàn),黃體期促排卵組的雌激素、孕酮及大卵泡個(gè)數(shù)均顯著高于卵泡期促排卵組,LH值水平卻因?yàn)楦咴型囊种谱饔蔑@著低于對(duì)照組。由于抑制了LH峰的出現(xiàn),卵子早排幾率下降,獲得卵子質(zhì)量也有提高,主要表現(xiàn)為黃體期促排卵組卵子正常受精率、優(yōu)質(zhì)胚胎率及臨床妊娠率顯著高于卵泡期促排卵組,其差異有統(tǒng)計(jì)學(xué)意義。結(jié)果還顯示卵泡促排卵期組的周期取消率高于黃體期促排卵組,差異有統(tǒng)計(jì)學(xué)意義,考慮可能因微刺激方案,卵泡發(fā)育不同步或者沒(méi)有進(jìn)行垂體降調(diào),過(guò)高的LH值導(dǎo)致優(yōu)勢(shì)卵母細(xì)胞完成第一次減數(shù)分裂,導(dǎo)致卵子提前成熟、黃素化,卵母細(xì)胞質(zhì)量下降,導(dǎo)致無(wú)可移植胚胎。見(jiàn)表2。
3 討論
卵巢低反應(yīng)(POR)是指卵巢對(duì)促性腺激素(Gn)刺激(超促排卵)反應(yīng)不良的病理狀態(tài)。主要表現(xiàn)為卵巢刺激周期發(fā)育的卵泡數(shù)量少,血E2峰值低、Gn用量多、周期取消率高、獲卵數(shù)少和較低的臨床妊娠率,并常伴有卵母細(xì)胞的受精率低和胚胎質(zhì)量低下[6]。有研究報(bào)道,年齡、基礎(chǔ)AFC、基礎(chǔ)FSH及血清AMH是臨床預(yù)測(cè)卵巢功能低下較好的指標(biāo)[7-9],本研究對(duì)象平均年齡≥35歲,平均基礎(chǔ)AFC≤5個(gè),基礎(chǔ)FSH>10 U/L,血清AMH低,均提示患者卵巢儲(chǔ)備功能低下,而兩組患者的一般資料均無(wú)顯著性差異(P>0.05),說(shuō)明本研究具有可比性。通過(guò)超促排卵從卵巢低反應(yīng)患者有限的儲(chǔ)備卵泡中獲得足量、優(yōu)質(zhì)的卵子是我們臨床醫(yī)生努力的方向。以往臨床常用的促排卵方案以卵泡期促排為理論基礎(chǔ),包括改良超長(zhǎng)方案、拮抗劑方案、長(zhǎng)方案、微刺激方案、短方案及自然周期方案等,其中微刺激因其減輕了患者的卵巢損耗,保持卵巢對(duì)Gn的敏感性,可重復(fù)性高,OHSS發(fā)生率低,被認(rèn)為是卵巢低反應(yīng)或多次IVF-ET失敗患者的首選。但其獲卵少,正常受精率及臨床妊娠率低,再次迫使臨床醫(yī)生尋找新的方案。近年的研究顯示人類卵泡募集形式是多個(gè)卵泡波模式,即一個(gè)排卵間期(interovulational interval,IOI)內(nèi)有2或3個(gè)卵泡波。黃體期出現(xiàn)的卵泡在發(fā)育過(guò)程中不一定閉鎖而是另一批卵泡募集發(fā)育的開(kāi)始[3]。Hall JE等[10]提出LH峰后12 h FSH升高,可見(jiàn)黃體期卵泡募集就已經(jīng)開(kāi)始,而卵巢低反應(yīng)患者相對(duì)更早,根據(jù)這一理論,人們發(fā)現(xiàn)黃體期給予FSH或CC等可使卵泡在高孕酮的環(huán)境下解除閉鎖,繼續(xù)生長(zhǎng)發(fā)育,引起黃體期出現(xiàn)卵泡周期募集從而獲得成熟卵[11]。這提示我們可以根據(jù)特有的卵巢周期變化特點(diǎn),一個(gè)月經(jīng)周期多次促排以獲得有用卵泡,增加胚胎利用率,以使POR患者獲得臨床妊娠。有學(xué)者[12,13]對(duì)卵巢反應(yīng)正常患者行黃體期GnRH拮抗劑方案促排卵,獲得較滿意的妊娠率。Wolff MV等[14]對(duì)40例要求保留生育能力,即將接受化療的癌癥婦女的隨機(jī)對(duì)照研究中發(fā)現(xiàn),卵泡期和黃體期促排卵均獲得成熟卵泡和優(yōu)質(zhì)胚胎。Bedoschi GM等[15]對(duì)1例24歲患有霍奇金淋巴瘤的未婚女性,采用黃體期促排卵,經(jīng)過(guò)7 d 卵巢刺激,共獲得12枚成熟卵母細(xì)胞行玻璃化冷凍。Maman E等[16]研究顯示卵泡期和黃體期來(lái)源的卵母細(xì)胞,其成熟率、受精率并無(wú)統(tǒng)計(jì)學(xué)差異。這與Buendgen HK等[12]研究結(jié)果相似。
本研究結(jié)果顯示,黃體期促排卵患者在HCG注射日的E2、P均顯著高于卵泡期促排卵,LH低于卵泡期促排卵的患者。究其原因可能是已經(jīng)接受過(guò)內(nèi)源性FSH刺激的小卵泡發(fā)展到卵泡后期,顆粒細(xì)胞數(shù)目增多并出現(xiàn)FSH受體數(shù)量也隨之增加,有的或許已經(jīng)具備分泌雌激素的能力,黃體期在大量外源性CC及FSH的繼續(xù)刺激下,顆粒細(xì)胞進(jìn)一步增殖,加上內(nèi)源性雌激素和高水平孕激素協(xié)同作用,促進(jìn)了雌激素的大量分泌,從而導(dǎo)致黃體期促排卵的卵泡刺激天數(shù)和Gn的用量少于卵泡期,但差異無(wú)統(tǒng)計(jì)學(xué)意義。這與Li YM等[17]研究結(jié)果一致。高水平的孕酮反而抑制了LH分泌,另外CC競(jìng)爭(zhēng)性結(jié)合下丘腦受體,負(fù)反饋刺激FSH釋放,促使卵泡發(fā)育,其次,通過(guò)使高水平E2對(duì)下丘腦的正反饋?zhàn)饔脺p少,抑制內(nèi)源LH的分泌,從而出現(xiàn)卵泡期促排卵的LH值高于黃體期促排卵。即使在高孕激素濃度下,黃體期促排卵獲得成熟卵母細(xì)胞并不少于卵泡期,其受精率和優(yōu)質(zhì)胚胎形成率也明顯升高,表明黃體期高孕激素對(duì)卵母細(xì)胞和胚胎無(wú)負(fù)面影響。這可能與孕激素抑制LH峰出現(xiàn),進(jìn)一步降低卵泡內(nèi)雄激素,從而解除卵泡對(duì)自身及其他卵泡發(fā)育的抑制,改善卵母細(xì)胞受精潛能,可用胚胎數(shù)增加。近期的一項(xiàng)病例對(duì)照研究結(jié)果也顯示黃體期促排卵組的受精率高于卵泡期促排卵組,但其沒(méi)有進(jìn)一步研究胚胎發(fā)育情況。這與Kucuk T[18]和Kansal Kalra S[19]等研究結(jié)果相似。這可能因?yàn)橥庠葱愿叩腇SH作用下抑制了卵泡的閉鎖,使獲得卵子數(shù)量增多,導(dǎo)致優(yōu)質(zhì)胚胎的數(shù)也增加。
本研究結(jié)果還顯示,黃體期促排卵組的臨床妊娠率顯著高于對(duì)照組(P<0.05),也高于Kucuk T等[18]研究的20.1%,但是Kucuk T等[18]認(rèn)為兩組的臨床妊娠率無(wú)顯著差異。某項(xiàng)薈萃分析的研究結(jié)果與Kucuk T等[18]結(jié)果相似,認(rèn)為黃體期促排卵并不能增加臨床妊娠率[20]。Kuang Yanping等[21]研究發(fā)現(xiàn)黃體期促促排卵的患者在第1次FET時(shí)臨床妊娠率高達(dá)54%,明顯高于本研究的妊娠率。2009年美國(guó)張進(jìn)博士報(bào)道,1例卵巢低反應(yīng)婦女在經(jīng)歷1次自然周期和7次微刺激周期獲卵并胚胎移植失敗后,在黃體期用CC促排卵獲得1枚優(yōu)質(zhì)卵子后成功受精,冷凍1枚胚胎后解凍移植,順利分娩1名健康嬰兒。還有學(xué)者提出黃體期聯(lián)合卵泡期促排卵后可得到更好的質(zhì)量的卵母細(xì)胞和滿意的臨床妊娠結(jié)局[22]。Oliveira JB[23]等提出采用黃體期GnRH拮抗劑促排卵方案可顯著提高ICSI的臨床妊娠率。這與本研究結(jié)果一致。這可能是因?yàn)辄S體期促排卵子宮內(nèi)膜與胚胎發(fā)育是不同步的,需要行全胚冷凍,因此對(duì)實(shí)驗(yàn)室的胚胎冷凍技術(shù)要求較高。也正因?yàn)槿绱?,POR患者采用自然周期FET,可能因子宮內(nèi)膜容受性優(yōu)于促排卵周期,再加上高質(zhì)量的胚胎,使其新鮮周期臨床妊娠率高于促排卵周期,Ata B等[24]的隨機(jī)對(duì)照研究顯示,自然周期組較拮抗劑和微剌激組移植成功率高,甚至提出,卵巢低反應(yīng)患者最好在新鮮周期移植以獲得滿意的結(jié)局。
綜上所述,沒(méi)有一種絕對(duì)優(yōu)良的促排卵方案針適合卵巢低反應(yīng)患者,其促排卵方案也是多樣性的,臨床醫(yī)生需要根據(jù)患者的綜合情況制定個(gè)體化的方案[25]。針對(duì)卵泡期促排方案失敗的POR患者,黃體期促排卵方案取卵可作為新的值得探索促排卵方案,但仍需進(jìn)一步大樣本前瞻性研究進(jìn)行臨床效果驗(yàn)證。
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