Hum. Reprod. Advance Access originally published online on December 22, 2005
Human Reproduction 2006 21(4):1055-1061; doi:10.1093/humrep/dei441
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Clinical use of the perifollicular vascularity assessment in IVF cycles: a pilot study
1 Department of Obstetrics & Gynecology, University "Magna Graecia" of Catanzaro, Catanzaro, 2 Department of Molecular & Clinical Endocrinology and Oncology, 3 Department of Clinical and Experimental Medicine, 4 Department of Obstetrics & Gynecology, University ‘Federico II’ of Naples and 5 Centre for Reproductive Biology, ‘Villa del Sole’ Clinic, Naples, Italy
6 To whom correspondence should be addressed at: Department of Gynecology & Obstetrics, Via M. Greco 10 vico XI, 88100 Catanzaro, Italy. E-mail: stefanopalomba{at}tin.it
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and methodsResultsDiscussionReferences |
|---|
BACKGROUND: In Italy, a recent law has imposed a ban on the fertilization of more than three oocytes at one time, and all resulting embryos produced must be transferred simultaneously. The aim of the present controlled study was to assess the clinical feasibility and efficacy of the perifollicular vascularity assessment for oocyte selection in IVF cycles. METHODS: Fifty-four young primary infertile non-obese women (27 cases and 27 age- and BMI-matched controls) underwent IVF cycles. The choice of the oocytes to fertilize was performed according to perifollicular vascularization in the experimental group, whereas in the control group, the standard morphologic criteria alone were used. The dose of gonadotrophins used, the dominant follicles obtained, the duration of the ovarian stimulation, the number of oocytes retrieved, the number/quality of oocytes fertilized and of cleaved embryos, cycle cancellation, implantation, clinical pregnancy, ongoing pregnancy, multiple pregnancies and ovarian hyperstimulation syndrome rates were assessed in each group. RESULTS: The assessment of perifollicular vascularity was feasible in 88.9% of cases. No difference between groups was detected in any parameter evaluated. CONCLUSION: Power Doppler assessment of perifollicular vascularity seems to have no clinical utility for oocyte selection in IVF cycles for young infertile women.
Key words: Doppler/embryos/infertility/IVF/oocytes
|
Introduction |
|---|
|
TopAbstractIntroductionMaterials and methodsResultsDiscussionReferences |
|---|
In February 2004, a law (n. 40/2004) regulating assisted reproduction techniques (ARTs) was approved in Italy (Boggio, 2005
; Conti and Delbon, 2005). Even though this is the first attempt to regulate the treatment of infertility in Italy, it contains several prohibitions and restrictions. Specifically, during an assisted reproduction cycle, no more than three oocytes can be fertilized at one time, and all embryos obtained must be transferred simultaneously.
In a recent multicentre survey (Ragni et al., 2005), the clinical impact of these limitations was evaluated, showing that the new legislation has induced only a small change in the success rate of ARTs using fresh embryos. These data are encouraging, even if altered by several biases due to the retrospective design of the study.
The outcome of the IVF techniques is strongly correlated with the quality of transferred embryos (choosing the right embryos) (Steer et al., 1992; Zollner et al., 2002). In particular, the implantation and the pregnancy rates have shown to improve significantly after embryo culture and transfer of embryos at blastocyst stage (Edwards and Craft, 1990; Gardner et al., 1998). Furthermore, these procedures seem to be effective only when a high cohort of normal oocytes is fertilized (Rijnders and Jansen, 1998; Bongso and Gardner, 1999; Zollner et al., 2002). Unfortunately, this prerequisite is actually illegal in Italy, and an optimal oocyte selection can be considered as the only one crucial factor in determining the outcome of the IVF cycle.
Experimental data have demonstrated that perifollicular blood flow assessment is a good marker of oocyte competence (Nargund et al., 1996a,b; Van Blerkom et al., 1997), embryo viability (Nargund et al., 1996a; Huey et al., 1999) and subsequent implantation potential (Gregory, 1998). Several studies (Chui et al., 1997; Bhal et al., 1999, 2001; Coulam et al., 1999; Borini et al., 2001; Costello et al., 2004) have also shown higher pregnancy rates when embryos resulting from the fertilization of eggs from better perfused follicles are transferred.
The aim of the present study was to evaluate in a clinical setting whether the assessment of the perifollicular vascularity is a feasible and useful procedure for the selection of oocytes with the best developmental potential in IVF programmes when only a limited number of oocytes can be fertilized.
|
Materials and methods |
|---|
|
TopAbstractIntroductionMaterials and methodsResultsDiscussionReferences |
|---|
The procedures used were in accordance with the guidelines of the Helsinki Declaration on human experimentation. The study was approved by the Institutional Review Board of the University "Magna Graecia" of Catanzaro. The purpose of the protocol was carefully explained to each woman, and a written consent was obtained from them before beginning the study.
Patients
Between September 2004 and February 2005, we enrolled 27 women with tubal factor or unexplained infertility undergoing IVF programmes in our department (experimental group). The diagnosis was established by hysterosalpingography and/or laparoscopic dye test and with partner’s semen analysis.
We excluded patients aged <18 years and >30 years, with third day FSH levels >10 IU/l, BMI (<18 and >30 kg/m2), peritoneal factor infertility (i.e., endometriosis and adhesions), polycystic ovaries (PCO) and/or other organic pelvic diseases and with any abnormality in partner’s semen analysis. Other exclusion criteria were: neoplastic, metabolic (including insulin resistance), endocrinological [including polycystic ovary syndrome (PCOS) or hyperandrogenism], hepatic and cardiovascular disorders or other concurrent medical illness (including asthma); abuse of alcohol; and current or previous (a washout period of at least 6 months was considered appropriate before enrolment) use of hormonal drugs.
Twenty-seven other infertile women with the same characteristics and age- and BMI-matched with the experimental group were enrolled and considered as controls (control group).
Protocol and treatment
In all patients, pituitary function was down-regulated by use of leuprolide acetate depot (Enantone 3.75 mg, Takeda, Rome, Italy) administered in the mid-luteal phase of the previous cycle (7 days before the expected menses). Recombinant FSH (rFSH, Gonal F 1050, Serono, Rome, Italy) was used to induce a controlled ovarian hyperstimulation (COH). Specifically, rFSH was initially administered at a starting dose of 150 UI/day intramuscularly injected for 5 days and then personalized according to ovarian response. Because, to date, there is no study evaluating the efficacy/safety ratio of protocols for inducing COH in IVF programmes with the intention to retrieve no more than three oocytes, the choice to start with a dose of 150 IU was made, taking into consideration that all enrolled patients were affected by primary infertility (first attempt to induce COH); none of them had PCOS or had PCO, and they were mildly overweight.
In the presence of at least three leading follicles (mean diameter >18 mm), HCG (Gonasi HP 5000, Amsa, Rome, Italy) 10 000 IU was intramuscularly injected 24 h after the last rFSH injection to complete oocytes maturation and to trigger ovulation.
Monitoring of the ovulation induction was performed by serial transvaginal ultrasonography (TV-USG) and serum estradiol (E2) evaluation. Both TV-USG scans and serum E2 determinations were performed every 3 days beginning fifth day after treatment starting and then daily when follicular dimensions achieved at least 15 mm. The follicular dimensions were calculated using the arithmetic mean of the two main diameters of each follicle.
In the experimental group alone, as detailed below, a power Doppler assessment of perifollicular vascularity was performed on the day of HCG injection and oocyte retrieval. All exams performed on the day of HCG injection were recorded and then re-observed before the second assessment (day of oocyte retrieval). Each patient was instructed to not smoke and/or drink coffee/tea and/or use any kind of medication within 1 h of each exam.
Transvaginal oocyte retrieval was performed 36 h after HCG injection. Specifically, after patient sedation with IV propofol, oocyte retrieval was performed using a 17G double-lumen aspiration needle with a low pressure. For each patient, the retrieved oocytes were individually cultured, marking the test tube and, successively, the culture plate with a code corresponding to perifollicular vascularity degree.
The retrieved oocytes were washed, and the mature oocytes, determined by the presence of a first polar body (metaphase II, MII oocytes), were observed and classified by an experienced biologist (B.D.) initially blinded to previous perifollicular vascularization. In the experimental group, the best oocytes were initially selected by the same biologist using morphological criteria (microscopic detection of oocyte anomalies, as detailed below), and then the three MII oocytes for transfer were chosen according to the best perifollicular vascularization (high-grade follicles, as detailed below). On the other hand, standard morphological criteria alone were used for the selection of the best three oocytes to transfer in the control group.
In both groups, the three MII oocytes were inseminated at 4 h after recovery with 10 000–20 000 motile sperm and placed in the CO2 incubator at a temperature of 37°C in 5% CO2 in air. Fertilization was evaluated 18 h after IVF and confirmed by the presence of two pronuclei and two polar bodies. The fertilized oocytes were classified with a well-standardized scoring system for zygotes and cultured for a total of 48 h from oocyte retrieval. Before transfer, the cleavage embryos were again graded. All embryos, with exclusion of the arrested embryos, were replaced in each patient as legally required by Italian legislation. Embryos that did not cleave after 24 h were considered to be arrested.
All embryo transfers were performed by the senior physician (F.Z.) without ultrasonographic guidance. The embryo transfers were routinely performed by means of Ultrasoft Frydman catheter (Laboratoire C.C.D., Paris, France), whereas a rigid catheter (Labotect, Labor-Technik, Gottingen, Germany) was used for the difficult embryo transfers. Difficult embryo transfer was defined as a procedure involving at least one of the following: cervical resistance leading to a prolonged procedure (>5 min), the need to use increased force or cervical grasping, requirement of cervical dilatation, the presence of blood on the catheter or multiple sequential attempts because of embryos retained in the catheter system.
In all patients, the luteal phase was supported by natural progesterone (100 mg daily IM, Prontogest, Amsa).
To avoid other potential selective bias and to eliminate the confounding effect of multiple cycles from the same individual, the study was limited to the first cycle of treatment for each patient.
Perifollicular vascularity assessments
All subjects underwent TV-USG examinations by the same experienced operator (T.R.) with the use of an ultrasonic scanner (Aplio, Toshiba Medical Systems, Rome, Italy) equipped with a 7.5 MHz vaginal probe. During each ultrasonographic examination, the ovarian and follicular dimensions were assessed in both groups, whereas the perifollicular vascularity was studied only in the experimental group.
Specifically, in each ovary, the perifollicular vessels around every dominant follicle were identified with the use of a power Doppler system, and the vascularity of each ovulatory follicle was studied by a single operator (A.F.) with the use of an advanced image analysis software (Image-Pro Plus 4.5, Media Cybernetics, Silver Spring, MD, USA). The extension of vascularity was graded using a well-validated grading system (Chui et al., 1997). The grading system consisted of assessing the percentage of follicular circumference in which flow was identified from a single cross-sectional slice. The grading system was as follows: F1, with vascularity 
25% of follicular circumference; F2, with vascularity between 26 and 50% of follicular circumference; F3, with vascularity between 51 and 75% of follicular circumference; and F4 with vascularity >75% of follicular circumference. The periovulatory follicles were categorized as high (grades 3–4) or low grade (grades 1–2) (Chui et al., 1997; Bhal et al., 2001).
The efficacy of perifollicular vascularity assessment to predict the oocyte quality (see below) was evaluated calculating the sensitivity and the specificity of this test, and considering as golden standard procedure the morphologic assessment of oocyte. In particular, were considered as ‘true positive’ the oocytes without morphologic anomalies (grade I) and with positive test (high-grade perifollicular vascularity).
Bias due to inter-observer error was avoided because the ultrasonographic assessments were performed by the same operator. The intra-observed error was evaluated in 10 healthy women in fertile age by three consecutive measurements at 15-min intervals and calculated using analysis of variance. The intra-observer coefficient of variation for the perifollicular vascularity was of 5%. No intra-observer variation was detected for the perifollicular grading.
Oocyte and embryo quality evaluations
Oocyte and embryo quality was assessed by a single expert embryologist (B.D.) using the setting for microscopic observations (x400 magnification) and bright-field constant during the study. As described before, morphologic criteria (alone or in combination with perifollicular vascularity) were used to assess the best oocytes. In particular, MII oocytes were graded into three groups according to the number of anomalies: grade I, oocytes without any anomaly; grade II, oocytes with one anomaly; and grade III, oocytes with at least two anomalies (Mikkelsen and Lindenberg, 2001). Oocytes without any anomaly showed a clear cytoplasm with uniform texture and homogeneous fine granularity, a round or ovoid first polar body with smooth surface and perivitelline space of normal size. On the other hand, the following morphological signs were considered as anomalies: rough or fragmented first polar body and/or a large perivitelline space (extracytoplasmic anomalies), and/or dark cytoplasm, granular cytoplasm or cytoplasmic inclusions, i.e. vacuoles or refractile bodies (cytoplasmic anomalies). The three oocytes with the highest grade were considered ‘the best’ oocytes to fertilize in the control group, whereas in the experimental group, they were selected also according to the better perifollicular vascularity.
Eighteen hours after insemination, zygotes were categorized according to the revised zygote scoring system proposed by Scott et al. (2000): Z1, equal pronuclei, equal number (between three and seven) and size of nucleoli, aligned in both pronuclei at the pronuclear junction; Z2, equal pronuclei, equal number (between three and seven) and size of nucleoli, scattered in both pronuclei; Z3, equal pronuclei, equal number (between three and seven) and even or/and uneven size of nucleoli, aligned in one pronucleus at the pronuclear junction, and randomly scattered in the other pronucleus; Z4, unequal or separated pronuclei.
Forty-eight hours after insemination, cleaved embryos were again categorized according to the embryo morphology and the relative proportion of anucleate fragments present in the zona pellucida: grade 4, embryos with regular, equal-sized and spherical blastomeres without extracellular fragmentation; grade 3, embryos with regular blastomeres and with light extracellular fragmentation (<10%); grade 2, embryos with blastomeres slightly irregular in size and shape with moderate extracellular fragmentation (10–50%); and grade 1, barely defined embryos or embryos with severe extracellular fragmentation (>50%) (Bolton et al., 1989; Bongso and Gardner, 1999; Zollner et al., 2002).
Main reproductive outcome measures
For each cycle, the serum E2 levels, the number of dominant follicles on the day of HCG administration, the duration of ovarian stimulation and the units of rFSH administered were recorded. The concordance between the ultrasonographic grading score and the oocyte degree was also evaluated in each case.
In each group, the cycle cancellation, the fertilization, the implantation, the clinical and ongoing pregnancy rates were evaluated. The number of multiple pregnancies and ovarian hyperstimulation syndromes (OHSS) was also recorded in both groups.
The absence of follicular response after 35 days of treatment or a serum E2 value >2500 pg/ml was considered as indication for abandoning the cycle (cancelled cycle). The cycle-cancellation rate was calculated as percentage of cancelled cycles/total number of cycles started. Implantation rate was defined as percentage of intrauterine gestational sacs/total transferred embryos. A rising 
-HCG (first -HCG assessment performed on fifteenth day after embryo transfer) and the sonographic evidence of intrauterine gestational sac and fetal cardiac activity at 7 weeks of pregnancy were considered criteria to define a clinical pregnancy. Clinical pregnancy rate was defined as percentage of clinical pregnancies/total non-cancelled cycles. Ongoing pregnancy was defined as a vital pregnancy confirmed by ultrasonography at 12 weeks of gestational age. Ongoing pregnancy rate was defined as percentage of ongoing pregnancies/total non-cancelled cycles.
Statistical analysis
The primary end-point of the current study was the implantation rate. At the study design, no data were available in literature for calculating the pre-study sample size due to the absence of data regarding the clinical usefulness of the perifollicular vascularity assessment. On the basis of these considerations, it was decided to determine the sample size according to the data obtained during the first 6 months of study. Considering the differences obtained in statistical comparisons between groups (difference in proportions was –0.04; 0.25 versus 0.29, for experimental and control group, respectively), a sample size of 1933 patients per group would be required in order to detect a clinical effect of the perifollicular vascularity assessment in either direction (two-tailed test) on our primary end-point with a statistical power of 80% for avoiding a type II error and a 5% chance of making a type I error. Because of the meaningless of the statistical difference in clinical terms, we decided to stop enrolment after 6 months from study start.
Data were analysed with the intention-to-treat (ITT) procedure and expressed as mean or median. The Kolmogorov–Smirnov statistic with a Lilliefors significance level was used for testing normality, and the unpaired t-test and the Mann–Whitney U-test were applied as appropriate. For categorical variables, the Pearson’s Chi-square test or exact tests were applied as appropriate.
A P-value of 0.05 or less was considered significant. The Statistics Package for Social Science (SPSS 13.0.1 December 2004; SPSS, Chicago, IL, USA) was used for statistical analyses. The power analysis and the sample size calculation were performed using SamplePower release 2.0.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and methodsResultsDiscussionReferences |
|---|
No difference was detected in any clinical, hormonal and metabolic parameter between treatment groups. The two groups were well matched for age and BMI (Table I). For each group, 3/27 (11.1%) patients were normal weight (BMI of 19.9 ± 2.7 and 20.4 ± 2.1 kg/m2 for group A and B, respectively), and 24/27 (88.9%) patients were overweight (BMI of 27.4 ± 1.1 and 27.2 ± 1.0 kg/m2 for group A and B, respectively).
|
Table II summarizes the main results.
|
No cycle was cancelled for absence of follicular response after 35 days of treatment, while one cycle (1/27, 3.7%) was cancelled for high risk of OHSS development in the control group. Thus, the data shown were obtained on a total of 27 and 26 cycles for experimental and control groups, respectively.
In three cases (3/27, 11.1%), the power Doppler assessment of perifollicular vascularity was not feasible for the high number of leading follicles, and the only morphologic grading score for oocytes was used. According to the ITT principle, these cases were included in the experimental group.
The days of ovarian stimulation, the units of gonadotrophins used, the number of dominant follicles and the peak of serum E2 levels on day of HCG injection were not significantly different between groups (Table II).
No change in perifollicular vascularity degree was observed between the assessment performed on day of HCG injection and those performed on day of oocytes retrieval. The number of total retrieved oocytes and MII oocytes was not different between groups (Table II).
In Figure 1, the percentage of oocytes with different quality scores according to the perifollicular vascularization is shown. In particular, 94/122 (77.0%), 15/53 (28.3%) and 1/20 (5.0%) of the grade I, II and III oocytes, respectively, showed a high-grade perifollicular vascularity.
|
The sensitivity and the specificity of the perifollicular vascularity assessment (high-grade follicle) in the detection of a grade I oocyte were 86.1 and 93.2%, respectively.
The distribution of oocytes, zygotes and cleaved embryos with different quality was similar in the experimental and control groups (Table II).
No difference in fertilization rate was observed between the two groups (Table II).
In only two cases [1/27 (3.7%) and 1/26 (3.8%) for experimental and control group, respectively] was the embryo transfer not performed. No difference was detected between two groups in the percentage of patients who received three [14/27 (51.9%) versus 14/26 (53.8%) for experimental and control group, respectively], two [4/27 (14.8%) versus 3/26 (11.5%) for experimental and control group, respectively] or one [8/27 (29.6%) versus 7/26 (26.9%) for experimental and control group, respectively] embryos; this distribution was not statistically significant (P = 1.000). The cumulative pregnancy and multiple pregnancy rates in patients who received three, two and one embryo were not significantly different between experimental and control group (Table III).
|
The number of difficult transfers was equally distributed between the two groups [2/26 (7.7%) and 1/25 (4.0%) for the experimental and control group, respectively].
The two groups were similar in implantation, clinical, ongoing pregnancy and multiple pregnancy rates (Table II). In the experimental group, there were eight single pregnancies and two sets of twins, whereas in the control group, there were seven single pregnancies and one of twins and one of triplets. In two cases (one for each group; 1/27, 3.7%), an OHSS of mild degree was observed.
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and methodsResultsDiscussionReferences |
|---|
Implantation rate is probably the most important limiting factor in human ARTs. Several data seem to suggest that a late selection at the blastocyst stage is useful to better identify the embryos with the highest developmental potential and to improve implantation and pregnancy rates. In fact, the implantation rates for day 2 or 3 transfer are low (about 20%), whereas they can get as high as 40% for blastocyst transfer on day 5 or 6 (Edwards and Craft, 1990
; Gardner et al., 1998). The majority of the embryos failing to continue to develop in extended culture show multiple aneuploidies, suggesting a natural selection for embryos with chromosomal anomalies in vitro (Jones and Trounson, 1999). Moreover, there is no advantage in a long culture period if the number of available embryos is small (Rijnders and Jansen, 1998; Zollner et al., 2002) because only 45% of the fertilized oocytes will reach the blastocyst stage (Gardner et al., 1998) and about half of the embryos seen on day 3 will survive to day 5 (Behr et al., 1999).
Because, legally, it is no longer possible to fertilize more than three oocytes and, thus, to produce a significant number of embryos, the extension of embryo culture after day 2 is not a feasible procedure in Italy. Even if most Italian experts feel that the fertilization of just three oocytes could cut the success rates by about two-thirds (Turone, 2004), a recent study has shown that the efficacy of ARTs using fresh embryos is not significantly reduced (Ragni et al., 2005). Furthermore, these results were obtained in a retrospective fashion and, probably, influenced by several selection biases. In fact, stimulation protocols were significantly different in the two study periods, and the number of cycles (and of patients) in which frozen embryos and ICSI procedures were used was significantly higher during the pre-law period.
It has been suggested that the intrafollicular hypoxia resulting from the inappropriate perifollicular microvasculature development (Battaglia et al., 2000) could cause reduced metabolism and lower intracellular pH, reduce fertilization, increase the incidence of cytoplasmatic and chromosomal disorders, and, thus, result in embryos with multinucleated blastomeres and limited developmental ability (Van Blerkom et al., 1997).
A significant relationship between perifollicular blood flow, content of percent dissolved oxygen and developmental competence of the corresponding oocytes has been demonstrated (Van Blerkom, 1996). Oocyte quality is sensitive to hypoxic damage (Van Blerkom, 1998), and a good oxygenation appears to be a pivotal factor for an adequate oocytes spindle embryo (Gaulden, 1992; Nargund et al., 1996a). In fact, oocytes with cytoplasmic defects, disorganized chromosomes and cleavage stage embryos with multinucleated blastomeres seemed to be derived predominantly from severely hypoxic follicles having reduced vascularity and lower concentration of vascular endothelial growth factor (Van Blerkom et al., 1997; Van Blerkom, 1997, 1998). On the contrary, embryos with the highest implantation potential originate from well-vascularized and oxygenated follicles (Van Blerkom, 1998).
The perifollicular vascularity measured using colour Doppler ultrasonography correlates with the level of follicular oxygenation (Van Blerkom et al., 1997) and with oocyte recovery (Nargund et al., 1996a,b), oocyte developmental potential (Van Blerkom et al., 1997), embryo quality (Nargund et al., 1996a; Chui et al., 1997; Huey et al., 1999), subsequent implantation potential (Gregory, 1998) and pregnancy rate (Chui et al., 1997; Bhal et al., 1999; Coulam et al., 1999; Borini et al., 2001; Costello et al., 2004).
Chui et al. (1997) have shown a strong association between degree of perifollicular vascularity, assessed with the use of power Doppler ultrasound, and embryo implantation potential. In fact, significantly higher fertilization and pregnancy rates were demonstrated when oocytes were obtained from follicles with higher-grade perifollicular vascularity (Chui et al., 1997).
On the basis of these considerations, we designed the current pilot study in order to evaluate, in a clinical setting, the feasibility and the efficacy, if any, of perifollicular vascularity assessment for oocyte selection in IVF programmes. The perifollicular vascularization was assessed using the well-validated semiquantitative grading system (Chui et al., 1997; Bhal et al., 1999) identified by means of power Doppler ultrasonography and studied using an advanced imaging software.
Our data show that the ultrasonographic procedure is feasible in a high percentage of cases and confirm the significant relationship between perifollicular vascularity and oocyte quality. Furthermore, the assessment of perifollicular vascularization did not show to be useful in a clinical point of view. In fact, no difference was observed in any parameters evaluated between experimental and control groups.
Possible explanations could be: first, given the high number of oocytes with optimal quality (and vascularization) obtained in our sample population composed of young non-obese women with low basal FSH levels and the strong association between optimal quality oocytes (morphologically determined) and high-grade follicles, three good-quality oocytes retrieved from follicles with high-grade vascularization were transferred in almost all cases. Second, it is possible to suggest that the assessment of perifollicular vascularization using the available criteria is not a good discriminative tool within oocytes of grade I to select the oocyte with the best developmental potential.
Our findings are consistent with those obtained by Huey et al. (1999). This last study (Huey et al., 1999) also confirmed (Nargund et al., 1996a; Chui et al., 1997; Van Blerkom et al., 1997; Van Blerkom, 1997, 1998) that perifollicular colour Doppler provides an indirect index of oocyte–embryo development in IVF and already proposed the limited applicability of this parameter in a clinical setting.
Finally, the current study confirms that the perifollicular vascularity is related to good-quality oocytes, but it also demonstrates that it, even if feasible, is not a clinically useful procedure to improve the reproductive outcomes in young non-obese infertile patients who have undergone IVF programmes. Certainly, it is not possible to generalize our data. In poor-responder patients or in women with high basal FSH levels, the clinical value of the perifollicular vascularization assessment could also be limited because of the reduced number of follicles obtained or oocytes retrieved (Toner, 2003), whereas older patients, specifically with low basal FSH levels (van Rooij et al., 2003), could have some benefits.
|
References |
|---|
|
TopAbstractIntroductionMaterials and methodsResultsDiscussionReferences |
|---|
Battaglia C, Genazzani AD, Regnani G, Primavera MR, Petraglia F and Volpe A (2000) Perifollicular Doppler flow and follicular fluid vascular endothelial growth factor concentrations in poor responders. Fertil Steril 74,809–812.[CrossRef][Web of Science][Medline]
Behr B, Pool TB, Milki AA, Moore D, Gebhardt J and Dasig D (1999) Preliminary clinical experience with human blastocyst development in vitro without co-culture. Hum Reprod 14,454–457.
Bhal PS, Pugh ND, Chui DK, Gregory L, Walker SM and Shaw RW (1999) The use of transvaginal power Doppler ultrasonography to evaluate the relationship between perifollicular vascularity and outcome in in-vitro fertilization treatment cycles. Hum Reprod 14,939–945.
Bhal PS, Pugh ND, Gregory L, O’Brien S and Shaw RW (2001) Perifollicular vascularity as a potential variable affecting outcome in stimulated intrauterine insemination treatment cycles: a study using transvaginal power Doppler. Hum Reprod 16,1682–1689.
Boggio A (2005) Italy enacts new law on medically assisted reproduction. Hum Reprod 20,1153–1157.
Bolton VN, Hawes SM, Taylor CT and Parsons JH (1989) Development of spare human preimplantation embryos in vitro: an analysis of the correlations among gross morphology, cleavage rates, and development to the blastocyst. J In Vitro Fert Embryo Transf 6,30–35.[CrossRef][Web of Science][Medline]
Bongso A and Gardner DK (1999) Embryo development. In Trounson A and Gardner DK (eds) Handbook of In vitro Fertilization. CRC Press, London, pp. 167–177.
Borini A, Maccolini A, Tallarini A, Bonu MA, Sciajno R and Flamigni C (2001) Perifollicular vascularity and its relationship with oocyte maturity and IVF outcome. Ann NY Acad Sci 943,64–67.[CrossRef][Web of Science][Medline]
Chui DK, Pugh ND, Walker SM, Gregory L and Shaw RW (1997) Follicular vascularity – the predictive value of transvaginal power Doppler ultrasonography in an in-vitro fertilization programme: a preliminary study. Hum Reprod 12,191–196.
Conti A and Delbon P (2005) Medically-assisted procreation in Italy. Med Law 24,163–172.[Medline]
Costello MF, Sjoblom P and Shrestha SM (2004) Use of Doppler ultrasound imaging of the ovary durino IVF treatment as a predictor of success. In Rao KA, Brinsdon PR and Sathananthan H (eds) The Infertility Manual. JAYPEE Brothers Medical, New Delhi, pp. 344–349.
Coulam CB, Goodman C and Rinehart JS (1999) Colour Doppler indices of follicular blood flow as predictors of pregnancy after in-vitro fertilization and embryo transfer. Hum Reprod 14,1979–1982.
Edwards RG and Craft I (1990) Development of assisted conception. Br Med Bull 46,565–579.
Gardner DK, Vella P, Lane M, Wagley L, Schlenker T and Schoolcraft WB (1998) Culture and transfer of human blastocysts increases implantation rates and reduces the need for multiple embryo transfers. Fertil Steril 69,84–88.[CrossRef][Web of Science][Medline]
Gaulden ME (1992) Maternal age effect: the enigma of Down syndrome and other trisomic conditions. Mutat Res 296,69–88.[CrossRef][Web of Science][Medline]
Gregory L (1998) Ovarian markers of implantation potential in assisted reproduction. Hum Reprod 13 (Suppl. 4),117–132.
Huey S, Abuhamad A, Barroso G, Hsu MI, Kolm P, Mayer J and Oehninger S (1999) Perifollicular blood flow Doppler indices, but not follicular pO2, pCO2, or pH, predict oocyte developmental competence in in vitro fertilization. Fertil Steril 72,707–712.[CrossRef][Web of Science][Medline]
Jones GM and Trounson AO (1999) Blastocyst stage transfer: pitfalls and benefits. The benefits of extended culture. Hum Reprod 14,1405–1408.
Mikkelsen AL and Lindenberg S (2001) Morphology of in-vitro matured oocytes: impact on fertility potential and embryo quality. Hum Reprod 16,1714–1718.
Nargund G, Bourne T, Doyle P, Parsons J, Cheng W, Campbell S and Collins W (1996a) Associations between ultrasound indices of follicular blood flow, oocyte recovery and preimplantation embryo quality. Hum Reprod 11,109–113.
Nargund G, Doyle PE, Bourne TH, Parsons JH, Cheng WC, Campbell S and Collins WP (1996b) Ultrasound derived indices of follicular blood flow before HCG administration and the prediction of oocyte recovery and preimplantation embryo quality. Hum Reprod 11,2512–2517.
Ragni G, Allegra A, Anserini P, Causio F, Ferraretti AP, Greco E, Palermo R and Somigliana E (2005) The 2004 Italian legislation regulating assisted reproduction technology: a multicentre survey on the results of IVF cycles. Hum Reprod 20,2224–2228.
Rijnders PM and Jansen CA (1998) The predictive value of day 3 embryo morphology regarding blastocyst formation, pregnancy and implantation rate after day 5 transfer following in-vitro fertilization or intracytoplasmic sperm injection. Hum Reprod 13,2869–2873.
van Rooij IA, Bancsi LF, Broekmans FJ, Looman CW, Habbema JD and te Velde ER (2003) Women older than 40 years of age and those with elevated follicle-stimulating hormone levels differ in poor response rate and embryo quality in in vitro fertilization. Fertil Steril 79,482–488.[CrossRef][Web of Science][Medline]
Scott L, Alvero R, Leondires M and Miller B (2000) The morphology of human pronuclear embryos is positively related to blastocyst development and implantation. Hum Reprod 15,2394–2403.
Steer CV, Mills CL, Tan SL, Cambpell S and Edwards RG (1992) The cumulative embryo score: a predictive embryo scoring technique to select the optimal number of embryos to transfer in an in-vitro fertilization and embryo transfer programme. Hum Reprod 7,117–119.
Toner JP (2003) Age = egg quality, FSH level = egg quantity. Fertil Steril 79,491.
Turone F (2004) Italy to pass new law on assisted reproduction. Br Med J 328,9.
Van Blerkom J (1996) The influence of intrinsic and extrinsic factors on the developmental potential and chromosomal normality of the human oocyte. J Soc Gynecol Investig 3,3–11.[CrossRef][Web of Science][Medline]
Van Blerkom J (1997) Can the developmental competence of early human embryos be predicted effectively in the clinical IVF laboratory? Hum Reprod 12,1610–1614.[Web of Science][Medline]
Van Blerkom J (1998) Epigenetic influences on oocyte developmental competence: perifollicular vascularity and intrafollicular oxygen. J Assist Reprod Genet 15,226–234.[CrossRef][Web of Science][Medline]
Van Blerkom J, Antezak M and Schrader R (1997) The developmental potential of human oocyte is related to the dissolved oxygen content of follicular fluid: association with vascular endothelial growth factor levels and perifollicular blood flow characteristics. Hum Reprod 12,1047–1055.
Zollner U, Zollner KP, Hartl G, Dietl J and Steck T (2002) The use of a detailed zygote score after IVF/ICSI to obtain good quality blastocysts: the German experience. Hum Reprod 17,1327–1333.
Submitted on August 18, 2005; resubmitted on November 16, 2005; accepted on November 22, 2005.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  V. Y. Fujimoto, J. P. Kane, B. Y. Ishida, M. S. Bloom, and R. W. Browne High-density lipoprotein metabolism and the human embryo Hum. Reprod. Update, August 28, 2009; (2009) dmp029v2. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. H. M. Lozano, N. Frydman, J. M. Levaillant, S. Fay, R. Frydman, and R. Fanchin The 3D vascular status of the follicle after HCG administration is qualitatively rather than quantitatively associated with its reproductive competence Hum. Reprod., April 1, 2007; 22(4): 1095 - 1099. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. Ragni, M. Anselmino, A.E. Nicolosi, M.E. Brambilla, G. Calanna, and E. Somigliana Follicular vascularity is not predictive of pregnancy outcome in mild controlled ovarian stimulation and IUI cycles Hum. Reprod., January 1, 2007; 22(1): 210 - 214. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||