there are two types of gnrha , the multi - low - dose ( short - acting ) or the single depot ( long - acting ) .
the currently available depot products were prepared for endometriosis or fibroids , the objective being to achieve a profound pituitary desensitization for a protracted period of time . however , because of oversuppression , the ampoules of gonadotrophin used and the duration of cos cycle were increased without improving clinical outcomes when depot gnrha was compared with daily - low - dose gnrha in a recent cochrane review .
it might be enough to induce partial pituitary desensitization for ivf.[46 ] halving the dose of depot triptorelin has been studied against its full dose with similar or better clinical outcomes . following that , two studies compared a half - dose depot gnrha with short - acting gnrha in a long protocol .
they showed similar results , but the length of cos was longer and lh and estradiol levels were lower .
thus , we originally compared a one - third - dose depot triptorelin with a half - dose depot triptorelin in a long protocol .
the study was a prospective , randomized , open ( no blind ) clinical trial and approved by the ethics committee of sun yat - sen memorial hospital of sun yat - sen university .
because of no previous study for calculating the sample size , we decided that 100 patients would be enrolled in this prospective , randomized , and open clinical trial .
inclusion criteria were : ( 1 ) patients were 38 years old with infertility caused by tubal , idiopathic , male factors or polycystic ovary syndrome ( pcos ) ; ( 2 ) they had body mass index ( bmi ) of no more than 28 kg / m ; ( 3 ) serum follicle stimulating hormone ( fsh ) level was under 12 iu / l on day 3 of the previous menstrual cycle ; ( 4 ) they needed to undergo their first or second ivf / icsi treatment cycle ; and ( 5 ) they had no active endometriosis , adenomyoma or uterine fibroid . from january to december in 2005 , the eligible patients were randomized by a staff nurse into two treatment groups on the day of initiating down - regulation , using a sealed envelope supplied by the statistician , and then no blindness for patients and clinicians . in group
i ( 50 patients ) , pituitary desensitization was obtained with a one - third - dose ( 1.25 mg ) depot triptorelin ( dipherelin 3.75 mg , beaufour ipsen , paris , france ) in a single i.m . injection in mid - luteal phase ( day 21 ) of the menstrual cycle preceding treatment or on day 16 of oral contraceptive pill , and in group ii ( 50 patients ) with a half - dose ( 1.88 mg ) depot triptorelin on the same timing .
the 3.75-mg triptorelin depot was mixed with 2 ml sterile water for injection , then shaking the vial well after mixing , and used right away with 1 ml sterile syringe ; 0.67 ml and 1.0 ml medication contained 1.25 mg and 1.88 mg triptorelin depot , respectively .
after the confirmation of pituitary down - regulation on day 35 of the cycle by sonographic detection of an endometrium with the thickness of 5 mm and suppressed ovaries ( no antral follicles 10 mm ) and serum estradiol levels of 50 pg/ ml and lh levels of 5 iu / l , gonadotrophin stimulation with recombinant fsh ( gonal - f , serono , switzerland ) was started at the usual dose of 23 ampoules ( 150225 iu ) daily .
we adjusted the initial and ongoing dosage according to the patient 's age , antral follicle count , bmi , basic fsh level , and follicular growth response .
ovulation was induced with 10,000 iu of hcg ( profasi , serono , switzerland ) when at least one follicle had reached a diameter of 18 mm .
evaluation of the quality of embryos on day 3 according to  embryo grading  and embryos of modified hu 's grades 1 or 2 were considered of high quality ( 69 cell ; blastomeres of equal size ; 020% cytoplasmic fragments ) . as a rule , and when available , two embryos were transferred in young women ( < 35 years ) and three embryos were transferred in older women ( 3538 years ) or repeated ivf cycles .
embryo transfers were done under ultrasound guidance with a full bladder using a wallace catheter ( wallace ltd , colchester , england ) .
blood assays for -hcg measurement were performed 13 days after embryo transfer , with a result > 25 iu / l being considered biochemical pregnancy .
clinical pregnancy was confirmed with the detection of gestational sacs by ultrasound 45 weeks after the embryo transfer .
early pregnancy loss was defined as a biochemical pregnancy without subsequent ultrasound signs of gestational sacs .
implantation rate was calculated as the ratio of the number of gestational sacs over the number of transferred embryos .
blood samples were obtained on day 35 of menstrual cycle just before gonadotrophin was commenced for fsh , lh , and estradiol activity .
blood sample were obtained on the day of hcg administration and the day of embryo transfer for lh , estradiol , and progesterone activity .
all samples were centrifuged at 2000 g for 15 min , and measurements were performed on the same day .
fsh , lh , estradiol , and progesterone concentrations were measured by chemiluminescent immunoassay ( beckman coulter access 2 immunoassay system ( beckman coulter , fullerton , usa ) . the assay 's intra- and inter - assay coefficients of variation for fsh , lh , estradiol , and progesterone were 3.1% and 5.4% , 3.6% and 4.3% , < 8% and < 12% , and 6.1% and 7.51% , respectively .
the secondary outcomes were : length of gonadotrophin stimulation , amount of gonadotrophins used , peak estradiol on day of hcg administration , number of oocytes retrieved , clinical pregnancy rate per embryo transfer , implantation rate , first trimester abortion rate , and live birth rate .
independent samples t - test or mann  whitney test were used for continuous variables in both groups .
dichotomous variables were analyzed by chi - square test or fisher 's exact test , as appropriate .
the study was a prospective , randomized , open ( no blind ) clinical trial and approved by the ethics committee of sun yat - sen memorial hospital of sun yat - sen university .
because of no previous study for calculating the sample size , we decided that 100 patients would be enrolled in this prospective , randomized , and open clinical trial .
inclusion criteria were : ( 1 ) patients were 38 years old with infertility caused by tubal , idiopathic , male factors or polycystic ovary syndrome ( pcos ) ; ( 2 ) they had body mass index ( bmi ) of no more than 28 kg / m ; ( 3 ) serum follicle stimulating hormone ( fsh ) level was under 12 iu / l on day 3 of the previous menstrual cycle ; ( 4 ) they needed to undergo their first or second ivf / icsi treatment cycle ; and ( 5 ) they had no active endometriosis , adenomyoma or uterine fibroid . from january to december in 2005 , the eligible patients were randomized by a staff nurse into two treatment groups on the day of initiating down - regulation , using a sealed envelope supplied by the statistician , and then no blindness for patients and clinicians . in group
i ( 50 patients ) , pituitary desensitization was obtained with a one - third - dose ( 1.25 mg ) depot triptorelin ( dipherelin 3.75 mg , beaufour ipsen , paris , france ) in a single i.m .
injection in mid - luteal phase ( day 21 ) of the menstrual cycle preceding treatment or on day 16 of oral contraceptive pill , and in group ii ( 50 patients ) with a half - dose ( 1.88 mg ) depot triptorelin on the same timing .
the 3.75-mg triptorelin depot was mixed with 2 ml sterile water for injection , then shaking the vial well after mixing , and used right away with 1 ml sterile syringe ; 0.67 ml and 1.0 ml medication contained 1.25 mg and 1.88 mg triptorelin depot , respectively .
after the confirmation of pituitary down - regulation on day 35 of the cycle by sonographic detection of an endometrium with the thickness of 5 mm and suppressed ovaries ( no antral follicles 10 mm ) and serum estradiol levels of 50 pg/ ml and lh levels of 5 iu / l , gonadotrophin stimulation with recombinant fsh ( gonal - f , serono , switzerland ) was started at the usual dose of 23 ampoules ( 150225 iu ) daily .
we adjusted the initial and ongoing dosage according to the patient 's age , antral follicle count , bmi , basic fsh level , and follicular growth response .
ovulation was induced with 10,000 iu of hcg ( profasi , serono , switzerland ) when at least one follicle had reached a diameter of 18 mm .
evaluation of the quality of embryos on day 3 according to  embryo grading  and embryos of modified hu 's grades 1 or 2 were considered of high quality ( 69 cell ; blastomeres of equal size ; 020% cytoplasmic fragments ) . as a rule , and when available , two embryos were transferred in young women ( < 35 years ) and three embryos were transferred in older women ( 3538 years ) or repeated ivf cycles .
embryo transfers were done under ultrasound guidance with a full bladder using a wallace catheter ( wallace ltd , colchester , england ) .
blood assays for -hcg measurement were performed 13 days after embryo transfer , with a result > 25 iu / l being considered biochemical pregnancy .
clinical pregnancy was confirmed with the detection of gestational sacs by ultrasound 45 weeks after the embryo transfer .
early pregnancy loss was defined as a biochemical pregnancy without subsequent ultrasound signs of gestational sacs .
implantation rate was calculated as the ratio of the number of gestational sacs over the number of transferred embryos .
blood samples were obtained on day 35 of menstrual cycle just before gonadotrophin was commenced for fsh , lh , and estradiol activity .
blood sample were obtained on the day of hcg administration and the day of embryo transfer for lh , estradiol , and progesterone activity .
all samples were centrifuged at 2000 g for 15 min , and measurements were performed on the same day .
fsh , lh , estradiol , and progesterone concentrations were measured by chemiluminescent immunoassay ( beckman coulter access 2 immunoassay system ( beckman coulter , fullerton , usa ) . the assay 's intra- and inter - assay coefficients of variation for fsh , lh , estradiol , and progesterone were 3.1% and 5.4% , 3.6% and 4.3% , < 8% and < 12% , and 6.1% and 7.51% , respectively .
the secondary outcomes were : length of gonadotrophin stimulation , amount of gonadotrophins used , peak estradiol on day of hcg administration , number of oocytes retrieved , clinical pregnancy rate per embryo transfer , implantation rate , first trimester abortion rate , and live birth rate .
independent samples t - test or mann  whitney test were used for continuous variables in both groups .
dichotomous variables were analyzed by chi - square test or fisher 's exact test , as appropriate .
the clinical characteristics of the patients were comparable between the two groups [ table 1 ] .
lh and progesterone assays performed in each patient on the day of hcg administration showed no evidence of premature lh surge or luteinization in either group .
table 2 shows the hormonal pattern of the two groups of patients during ovarian stimulation . there were no significant differences in fsh , lh , and e2 levels on day 35 of menstrual cycle just before initiating gonadotrophin after down - regulation and lh , estradiol and progesterone levels on the days of hcg administration and embryo transfer .
however , on day 35 of menstrual cycle just before initiating gonadotrophin after down - regulation , fewer patients showed low - level lh ( < 1.0
iu / l ) and low - level estradiol e2 ( < 30 pg / ml ) in group i ( p < 0.05 )
. basic characteristics of the two groups comparison of hormone levels during ovarian stimulation between two groups the length of ovarian stimulation  the total dose of gonadotrophin used , and the number of oocytes retrieved showed no significantly differences ( p > 0.05 ) [ table 3 ] .
there were fewer total embryos and available embryos for cryopreservation in group i ( p < 0.05 ) , while high - quality embryo rate in was higher in group i ( p < 0.05 ) [ table 3 ] . fertilization rate and number of transferred embryos were not significantly different between two groups [ table 3 ] . clinical pregnancy , implantation , live birth , and early miscarriage rates showed no significantly differences between two groups ( p > 0.05 ) [ table 3 ] .
the use of a single - dose depot long - acting gnrha in a long protocol offers the advantages of better compliance , convenience , and economy of cost for patients with less stress of injections and risk of infection .
the recent cochrane review showed no significant difference in clinical pregnancy rate between the long protocol using depot or daily gnrha for ivf cycles .
however , because of profound pituitary desensitization , depot formulations require more gonadotrophin ampoules , which are needed for ovarian stimulation , and a significantly longer duration of ovarian stimulation than daily gnrha . previous study demonstrated a direct correlation between the reduction of the daily dosage of short - acting triptorelin and the decrease in the degree of pituitary suppression . to find a lower depot dose with sufficient suppression potential , several studies have shown that a half - dose ( 1.88 mg ) of triptorelin injection was sufficient to prevent lh surges , and similar or better ivf outcomes were obtained comparing full - dose triptorelin with half dose in cos .
a half - dose depot triptorelin in a long protocol has been accepted in ivf treatment . from 2001 to 2004 , a half - dose depot triptorelin was routinely used for the long protocol of cos in our ivf centre . however ,
when comparing half - dose depot gnrha with daily short - acting gnrha in a long protocol clinical , outcomes were not significantly different , but the length of gonadotrophin stimulation was significantly longer and estradiol level on day 3 and lh level on hcg day were lower in the protocol of half - dose depot gnrha . that indicated the half - dose depot gnrha would still cause profound suppression for ovarian stimulation .
thus , to investigate the efficacy of the further reduced depot dose in this study , we originally compared a one - third - dose depot triptorelin ( 1.25 mg ) with a half - dose depot triptorelin ( 1.88 mg ) in a long protocol for ivf or icsi and embryo transfer cycles .
both one - third dose and half - dose group showed adequate suppression and no premature lh surge .
there were fewer cases with lh < 1.0 iu / l and estradiol < 30 pg / ml on day 35 after down - regulation in one - third - dose group ( p < 0.05 ) .
there were fewer but still appropriate oocytes retrieved ( p = 0.086 ) and embryos obtained ( p < 0.05 ) in the one - third - dose group .
it seemed that there was a dose - finding effect of gnrha on the numbers of oocytes and embryos in women with normal ovarian reserve .
several studies demonstrated the similar dose - finding effect of gnrha on the degree of pituitary suppression with different doses of daily gnrha or full - dose and half - dose depot gnrha .
for the dose - finding effect of gnrha on the numbers of oocytes and embryos , previous studies show controversial results .
reported firstly a dose effect of short - acting daily triptorelin on the numbers of oocytes and embryos in normal responders .
they mentioned the possible mechanisms : a longer duration of stimulation with fsh with higher daily doses of agonist enables more follicles to enter the stage fsh - dependent growth ; a greater suppression of endogenous lh than fsh by the higher doses of gnrha results in an increase in the fsh / lh ratio during the follicular phase .
a recently study would suggest another mechanism , which showed that pituitary desensitization with gnrha results in a significant increase in anti - mullerian hormone ( amh ) levels , which may explain the enhanced ovarian response to conventional controlled ovarian stimulation .
but it is still unknown whether the effect of gnrha on amh levels is associated with the dose of gnrha .
these findings contrast with the work by dal prato et al . in their study ,
the low dose ( half - dose ) depot triptorelin gave rise to a higher number of oocytes and embryos than the full - dose depot triptorelin .
the difference between the two studies might result from the different degree of pituitary suppression .
full - dose depot gnrha in their study may cause too profound suppression and impair ovarian response to exogenous fsh .
another study by yim et al . showed no difference in the number of oocytes and embryos with full - dose or half - dose depot triptorelin .
the difference lies probably in the kind of gonadotrophin used : rfsh ( no lh activity ) in the present study and hmg ( with lh activity ) in that of yim et al . the administration of hmg may have partially balanced the effects of the different degrees of pituitary suppression on ovarian response . in the present study , there was a higher rate of high - quality embryos in one - third - dose group than that in half - dose group ( p < 0.05 ) .
clinical pregnancy , implantation , live birth , and early miscarriage rates showed no significant differences .
previous two studies compared a half - dose and full - dose depot triptorelin in the long protocol of ivf . in the study of dal prato et al . , a higher number of good - quality embryos and a higher cumulative pregnancy rate were obtained in the half - dose group than the full - dose group . in the present study
, similar results showed that decreased suppression improved the quality of embryos , and it is probably due to small sample size that the differences of clinical outcomes were not found significantly . in the study of yim et al .
, the data of embryo quality was not mentioned and the clinical outcome showed no differences .
both fsh and lh are required for a normal follicular growth and maturation according to the two - cell , two - gonadotrophin theory .
previous study in gnrh antagonist down - regulated primates shows that an intrafollicular environment depleted of lh and estradiol impairs oocyte maturation , embryo development , and implantation .
clinical studies in women with hypogonadal hypogonadism have shown that while follicular development can be achieved by stimulation with pure fsh preparations , concentrations of circulating estradiol and fertilization rates of retrieved oocytes are severely compromised compared with stimulation with preparations containing lh activity . for ivf treatment with gnrha down - regulation and fsh stimulation , profound pituitary gland suppression with lh levels of < 0.5
iu / l led to significantly lower e2 production,[1820 ] fewer oocytes , lower fertilization rate , and fewer embryos that were available for cryopreservation .
moreover , the study by tesarik et al . has suggested that endometrial maturation is disturbed in women with low endogenous lh , and a direct action of lh on uterus may be required to support endometrial growth and uterine receptivity .
another study shows that the expression of endometrial estrogens and progesterone receptors is altered in cos cycles with gnrh agonist and low lh levels .
gnrha has been shown to cause extra - pituitary side effects , including direct inhibition of ovarian steroidogenesis and effects on the differentiation of granulose cells .
these findings should furthermore suggest the use of the possibly lower dose of gnrh agonist .
finally , lower dose of depot gnrha might reduce the cost for patients undergoing assisted reproduction treatment . in our ivf centre
, three patients can share one ampoule of depot triptorelin . decreased pituitary suppression by lowering the dose of depot gnrha in our trial suggests that one - third - dose of depot gnrha may also reduce the lh requirement in patients undergoing ivf treatment .
although sample size was enough for evaluating the degree of pituitary suppression , it may be not adequate for comparing the clinical outcome after ivf .
further reduced dose of triptorelin depot and dose - finding effect had not been studied .
in conclusion , it has been shown in our study that one - third - dose ( 1.25 mg ) depot triptorelin can be successfully used in ovarian stimulation for ivf or icsi .
lh and estradiol levels confirm the reduced pituitary suppression caused by one - third - dose than half - dose depot triptorelin .
higher good - quality embryo rate could be explained better quality oocytes , while clinical outcome were similar between two groups .
whether a further reduced dose of depot gnrha still results in a similar or better outcome remains to be determined .
 objective : appropriate dosage of the long - acting depot gonadotrophin releasing hormone ( gnrh ) agonist has not been determined in long protocol for ivf , and one - third - dose depot triptorelin was compared with half - dose in a luteal long protocol of in - vitro fertilization/ intra cytoplasmic sperm injection ( ivf / icsi ) treatment in this study.materials and methods : this is a prospective , randomized , open clinical trial . 
 100 patients were randomized into two groups . 
 group i received one - third - dose ( 1.25 mg ) depot triptorelin . 
 group ii received half - dose ( 1.87 mg ) . 
 the clinical and experimental parameters were compared between the two groups.results:there was no premature luteinizing hormone ( lh ) surge in both groups . on day 35 of menstrual cycle after down - regulation 
 , fewer patients showed low - level lh ( < 1.0 
 iu / l ) and estradiol ( < 30 pg / ml ) in group i ( p < 0.05 ) . 
 there were fewer oocytes retrieved ( p = 0.086 ) , fewer total embryos and available embryos for cryopreservation in group i ( p < 0.05 ) , while good - quality embryo rate was higher in group i ( p < 0.05 ) . 
 the length and dose of ovarian stimulation was lower in group i , but not significantly . 
 the clinical pregnancy ( 52% versus 40% ) , implantation ( 48% versus 37.5% ) , delivery ( 46% versus 32% ) , or live birth ( 42% versus 32% ) rates and the abortion ( 8% versus 20% ) rates showed no significant differences.conclusion:depot triptorelin 1.25 mg can be successfully used with reduced pituitary suppression and lower cost in a long protocol for in - vitro fertilization . 
INTRODUCTION
MATERIALS AND METHODS
Study design
Patients
COS and IVF/ICSI procedure
Serum FSH, LH, estradiol, and progesterone determination
Assessment
Statistical analysis
RESULTS
DISCUSSION
CONCLUSION