Colour Doppler indices of follicular blood flow as predictors of pregnancy after in-vitro fertilization and embryo transfer

Applied Use of Doppler Ultrasonography in Bovine Reproduction

The use of Doppler ultrasonography to quantify blood vascularization in reproductive organs has increased over the past decade. Doppler technology has predominantly been explored in research settings to evaluate uterine blood flow and to assess follicular and luteal blood perfusion. Recent research has also explored the use of Doppler technology in applied reproductive management for both the beef and dairy industries and has focused on the use of luteal color Doppler ultrasonography to evaluate embryo transfer recipients and perform early pregnancy diagnosis. Although significant progress has been made and current literature indicates a strong potential for the applied use of Doppler ultrasonography to increase reproductive efficiency in the cattle industry, uptake of this technology is still currently limited. This review summarizes the recent developments in the applied use of color Doppler ultrasonography for reproductive management in both beef and dairy cattle herds.

Ovarian Stimulation in Assisted Reproductive Technology Cycles for Varied Patient Profiles: An Indian Perspective

Controlled ovarian stimulation has been an integral part of in vitro fertilisation (IVF) treatment cycles. Availability of different gonadotropins for ovarian stimulation and gonadotropin releasing hormone (GnRH) analogues for prevention of premature rise of leutinising hormone during follicular phase offer an opportunity to utilise them for a successful outcome in women with different subsets of ovarian response. Further, use of GnRH agonist as an alternative for human chorionic gonadotropin improves safety of ovarian stimulation in hyper-responders. Mild ovarian stimulation protocols have emerged as an alternative to conventional protocols in the recent years. Individualisation plays an important role in improving safety of IVF in hyper-responders while efforts continue to improve efficacy in poor responders. Some of the follicular and peri-ovulatory phase interventions may be associated with negative impact on the luteal phase and segmentalisation of the treatment with frozen embryo transfer may be an effective strategy in such a clinical scenario. This narrative review looks at the available evidence on various aspects of ovarian stimulation strategies and their consequences. In addition, it provides a concise summary of the evidence that has emerged from India on various aspects of ovarian stimulation.

Ovarian, uterine and luteal hemodynamic variations between pregnant and non-pregnant pluriparous Egyptian buffalos with special reference to their anatomical and histological features

This study determined the ovarian, uterine, and luteal hemodynamic variations using Doppler between pregnant and non-pregnant pluriparous buffalos in relation to their anatomical and histological basics during the first 31 days after natural mating. Adult healthy cyclic Egyptian buffalo (n = 10) were selected and categorized into two groups; group 1 (n = 5) was mated naturally by a fertile bull during the late estrus phase, and group 2 (n = 5) was not mated. Animals were subjected to Doppler ultrasonography to evaluate luteal, ovarian, and uterine blood flows from day 7 until day 31 post-mating. Besides, three pregnant (one month) and other non-pregnant uterus (n = 6) were obtained from a local abattoir to study the anatomical and histological features. Our results revealed that the luteal, ovarian, and uterine arteries cross-sectional diameters/mm increased (P < 0.05) from day 7 till day 31. Resistance (RI) and pulsatility indices (PI) decreased linearly (P < 0.05) in pregnant buffalos till day 31, but the peak systolic, end diastolic velocities and flow volume of those arteries were increased. Additionally, luteal colored areas away and toward CL were increased (P < 0.05) in the pregnant group compared to non-pregnant ones. There was a significant (P < 0.05) increase in the lumen diameter of luteal, ovarian, and uterine artery sections in pregnant buffalos compared to those of non-pregnant ones. While the mean value of tunica media's thickness of both luteal and uterine artery was significantly higher in non-pregnant buffalos than pregnant ones, except for that of the ovarian artery. Additionally, the ovarian and uterine artery tunica muscularis relative area % was (P < 0.05) higher in pregnant buffalos than in non-pregnant ones, except for that of the luteal artery. It was concluded that in pregnant buffalos, ovarian, uterine, and luteal blood flows were improved from the first week until 31 days post-mating via a decline in both Doppler indices with an increase in Doppler velocities and blood flow volume in relation to their histological changes based on their anatomical architecture in comparison to non-pregnant one.

Do physical activity, sitting time and body mass index affect fertility over a 15-year period in women? Data from a large population-based cohort study

STUDY QUESTION

Do physical activity (PA), sitting time (ST) and body mass index (BMI) affect fertility over a 15-year period in Australian women?

SUMMARY ANSWER

Moderate and high levels of PA confer advantages for fertility in women with normal BMI, but increased risk of infertility was observed in obese women.

WHAT IS KNOWN ALREADY

Higher BMI is positively associated with higher rates of problems with fertility, but the effects of physical activity and sitting time on fertility are less well understood.

STUDY DESIGN, SIZE, DURATION

Participants in The Australian Longitudinal Study of Women’s Health (ALSWH) completed mailed surveys in 2000, with follow-ups in 2003, 2006, 2009, 2012 and 2015 (N = 6130).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Participants were aged 22 to 27 in 2000. They were asked to report their physical activity levels, sitting time and fertility problems in each survey from 2000 to 2015. BMI was calculated from self-reported weight and height. Cumulative incidence of fertility problems was calculated from 2000 to 2015 and hazard ratios (HR) and 95% CIs were calculated using survival analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

From 2000 to 2015, the cumulative incidence of fertility problems was 15.4% (95% CI: 14.5–16.4). High levels of PA were associated with reduced risk of problems with fertility [HR 0.82 (95% CI: 0.69–0.98)], and higher BMI was positively associated with fertility problems [overweight: HR 1.18, (95% CI 0.99–1.39); obese: HR 1.36, (95% CI 1.14–1.63)]. In survival analyses, incidence rates were highest in every survey interval in women who reported low PA levels and in women who were obese. Overall, ST was not associated with fertility problems. In stratified models, high levels of PA attenuated the risk of problems with fertility in women who were in the normal BMI category [HR 0.64, (95% CI 0.49–0.82)].

LIMITATIONS, REASONS FOR CAUTION

The ALSWH relies on self-reported data, which may be subject to recall bias.

WIDER IMPLICATIONS OF THE FINDINGS

The study provides estimates of problems with fertility in a cohort of young adult Australian women, and the results indicate that these are inversely associated with physical activity levels and positively associated with BMI. However, the high infertility risk in obese women was not attenuated by high levels of PA. The protective effects of PA were only observed in women with normal BMI. As rates of developing problems with fertility were highest in every survey interval among women who reported low levels of physical activity and in women who were obese, these findings suggest that improving physical activity levels could be an affordable strategy to reduce problems with fertility in women who are trying to conceive. These findings should be considered by clinical and public health practitioners.

STUDY FUNDING/COMPETING INTEREST(S)

The ALSWH is funded by the Australian Government. Funding for these analyses was provided by a University of Queensland (UQ) International Postgraduate Research Scholarship and a UQ International Development Fellowship. The authors declare no conflicts of interest.

An objective volumetric method for assessment of ovarian follicular and luteal vascular flow using colour Doppler ultrasonography

Our goal was to develop an objective computer-assisted volumetric method of assessing vascular flow from colour Doppler ultrasound data of ovarian structures recorded by free-hand movement. We hypothesized that a vascularity index (ratio of the region of blood flood to the region of ovarian structure) obtained from the three-dimensional volumetric analysis would be more precise (less variable) than conventional two-dimensional analysis of single images in estimating the functional status of the preovulatory follicles and corpus luteum. Doppler ultrasound cineloops of water buffaloes (Bubalus bubalis; n = 22) ovaries were recorded daily from 12 h before GnRH treatment to four days after ovulation. Cineloops were processed using Fiji and Imaris software packages for segmenting the area (two-dimensional analysis) and the volume (three-dimensional analysis) occupied by the blood-flow and associated tissue to calculate the vascularity index. For volumetric measurement, all images in a cineloop were used (i.e., no a-priori selection of images) while for two-dimensional analysis, three images from the region with apparent maximum vascularity were selected. The volumetric method was verified with theoretical ellipsoidal volume of the follicle (r = 0.96 P < 0.01) or corpus luteum (r = 0.58 P = 0.02). The variability in the follicular vascularity index among animals was lower using the volumetric method than two-dimensional analysis (0.018 ± 0.002 vs 0.030 ± 0.005, P < 0.01), while the variability for CL vascularity was similar between methods (P = 0.23). An increase in the follicular vascularity index was detected at 12 h after GnRH treatment using both methods (two-dimensional: 0.030 ± 0.008, P < 0.01; three-dimensional: 0.016 ± 0.006, P < 0.02). Buffaloes that ovulated tended to have a greater increase in 3D vascularity index than non-responding buffaloes (P = 0.06); the two-dimensional method was not able to detect these changes. Using the three-dimensional method, a moderate positive correlation (r = 0.59; P = 0.02) was evident between the follicular vascularity index at 14-16 h after GnRH treatment and follicular diameter. In conclusion, an objective volumetric method for assessing relative ovarian blood flow changes was developed using Doppler ultrasound cineloops recorded by free-hand movement. The 3-dimensional method eliminates the need for a-priori selection of images and is more precise as a result of decreased technical variability.

Influence of follicular fluid and cumulus cells on oocyte quality: clinical implications

An equilibrium needs to be established by the cellular and acellular components of the ovarian follicle if developmental competence is to be acquired by the oocyte. Both cumulus cells (CCs) and follicular fluid (FF) are critical determinants for oocyte quality. Understanding how CCs and FF influence oocyte quality in the presence of deleterious systemic or pelvic conditions may impact clinical decisions in the course of managing infertility. Given that the functional integrities of FF and CCs are susceptible to concurrent pathological conditions, it is important to understand how pathophysiological factors influence natural fertility and the outcomes of pregnancy arising from the use of assisted reproduction technologies (ARTs). Accordingly, this review discusses the roles of CCs and FF in ensuring oocyte competence and present new insights on pathological conditions that may interfere with oocyte quality by altering the intrafollicular environment.

Perifollicular blood flow and its relationship with endometrial vascularity, follicular fluid EG-VEGF, IGF-1, and inhibin-a levels and IVF outcomes

PURPOSE

The aim of this study is to investigate the association of perifollicular blood flow (PFBF) with follicular fluid EG-VEGF, inhibin-a, and insulin-like growth factor-1 (IGF-1) concentrations, endometrial vascularity, and IVF outcomes.

METHODS

Forty women with tubal factor infertility were included in a prospective cohort study. Each woman underwent IVF/ICSI procedure. Individual follicles of ≥16 mm (n = 156) were evaluated by power Doppler analysis and categorized as well-vascularized follicles (WVFs) or poorly vascularized follicles (PVFs). WVFs referred to those with perifollicular vascularity of 51-100 %. Each follicular fluid (FF) was individually aspirated and FF/serum EG-VEGF, inhibin-a, and FF IGF-1 levels were evaluated. Zones III-IV endometrial vascularity was classified as a well-vascularized endometrium (WVE). The presence of a WVE and mature oocytes, in addition to the embryo quality and clinical pregnancy rate (CPR), were recorded for each follicle. The main outcome measures were FF serum EG-VEGF, inhibin-a, IGF-1 levels, and WVE and IVF outcome per PFBF.

RESULTS

For WVFs, the level of FF EG-VEGF (p = 0.008), oocyte quality (p = 0.001), embryo quality (p = 0.002), a WVE (p = 0.001), and CPR (p = 0.04) increased significantly. The pregnant group was characterized by increased numbers of WVFs (p = 0.044), a WVE (p = 0.022), and increased levels of FF IGF-1 (p = 0.001) and serum EG-VEGF (p = 0.03). FF IGF-1 >50 ng/mL (AUC 0.72) had 75 % sensitivity and 64 % specificity for predicting CPR.

CONCLUSIONS

WVFs yield high-quality oocytes and embryos, a WVE, increased FF EG-VEGF levels, and increased CPRs.

Follicle and corpus luteum size and vascularity as predictors of fertility at the time of artificial insemination and embryo transfer in beef cattle

Abstract:Two ultrasound based fertility prediction methods were tested prior to embryo transfer (ET) and artificial insemination (AI) in cattle. Female bovines were submitted to estrous synchronization prior to ET and AI. Animals were scanned immediately before ET and AI procedure to target follicle and corpus luteum (CL) size and vascularity. In addition, inseminated animals were also scanned eleven days after insemination to target CL size and vascularity. All data was compared with fertility by using gestational diagnosis 35 days after ovulation. Prior to ET, CL vascularity showed a positive correlation with fertility, and no pregnancy occurred in animals with less than 40% of CL vascularity. Prior to AI and also eleven days after AI, no relationship with fertility was seen in all parameters analyzed (follicle and CL size and vascularity), and contrary, cows with CL vascularity greater than 70% exhibit lower fertility. In inseminated animals, follicle size and vascularity was positive related with CL size and vascularity, as shown by the presence of greater CL size and vascularity originated from follicle with also greater size and vascularity. This is the first time that ultrasound based fertility prediction methods were tested prior to ET and AI and showed an application in ET, but not in AI programs. Further studies are needed including hormone profile evaluation to improve conclusion.

Embryo transfer in competition horses: Managing mares and expectations

Embryo transfer (ET) is an accepted and successful technique for obtaining foals from mares without interrupting their competition careers. Recent research, however, suggests that the potential of factors including heat, exercise, repeated embryo flushing and repeated manipulation of the reproductive cycle using exogenous hormones to have a negative impact on fertility may have been underestimated. This paper reviews the evidence base for involvement of these factors in repeated failures to recover embryos from nongeriatric competition mares without obvious clinical or pathological indications of reproductive abnormalities. It concludes that, for some mares at least, a cessation of exercise for the periovulatory period and the period between ovulation and embryo flushing, combined with careful management of flushing-induced endometritis, and minimal hormonal manipulation of the reproductive cycle, may be necessary to optimise embryo recovery rates. Mare owners may have been encouraged to request ET for their mares following high-profile examples in the media of elite mares that have produced foals by ET whilst competing. The veterinarian should educate mare owners about the multiple factors that may affect the chances of recovering an embryo from their mares, and should manage the expectations of mare owners so that they do not approach ET programmes in the expectation that there will be no disruption to their training and competition plans.

Ovarian and uterine periovulatory Doppler ultrasonography in bitches

This paper aims to describe the uterine and ovarian ultrasonographic characteristics and Doppler velocimetric features of their arteries in bitches during the periovulatory period. Fifteen estrous cycles in 10 animals were evaluated. The ultrasonographic characteristics, resistance indices (RI) and pulsatility indices (PI) of the uterus and ovaries in each animal were recorded 5 days before and after ovulation (D0). The data were statistically analyzed, and the results were expressed as the mean ± standard error of mean (P<0.05). In results the ultrasonographic features of the uterus were the same on all of the cycles and evaluated days. The uterus had an average diameter of 0.85±0.02cm. An increase in the volume of the ovaries and the diameter of the ovarian follicles were measured. Ovaries had a volume of 0.64±0.06cm³, and the follicles cavities had a diameter of 0.46 ± 0.01 cm on the day of ovulation. After ovulation, it was observed that some follicles not collapse in some cycles. Two days prior to ovulation, the uterine blood perfusion decreased. This decrease remained unchanged until ovulation. Following ovulation, we measured a gradual increase in the uterine perfusion and in the ovarian artery. This artery directed blood flow to the ovaries and increased the intra-ovarian perfusion on the day after ovulation. In conclusion, specific features are observed in the uterus and ovarian ultrasound image and Doppler values of their arteries presented on the periovulatory days and when associated allow to estimate more accurately the date of ovulation.

Periovulatory follicular volume and vascularization determined by 3D and power Doppler sonography as pregnancy predictors in intrauterine insemination cycles

PURPOSE

To evaluate the relationship between volume and vascularization of the periovulatory follicle and subfollicular area measured by three-dimensional power Doppler ultrasound (US), and ovulation and pregnancy in patients undergoing intrauterine insemination (IUI).

METHODS

We studied 79 consecutive cycles of IUI on hCG administration day. We measured the periovulatory follicle and subfollicular area by means of three-dimensional power Doppler US. The stored volumes were processed with the VOCAL image processing software to calculate the volume of the follicle and the following vascular indices: vascularization index (VI), flow index (FI), and vascularization flow index (VFI).

RESULTS

The follicular volume was higher in anovulatory cycles (7.7 ± 3.7 cubic centimeters (CC) versus 4.1 ± 2.0 CC; p < 0.001). There was no difference between the follicular volumes in cycles with or without subsequent pregnancy. The vascular indices of the follicle did not differ significantly between ovulatory and anovulatory cycles, and between cycles that did and did not achieve pregnancy. Periovulatory subfollicular VI and VFI were lower in women who became pregnant (VI: 2.9 ± 2.3% versus 5.6 ± 4.6%; p < 0.05, and VFI: 1.1 ± 0.8 versus 2.2 ± 2.2; p < 0.01).

CONCLUSIONS

High values of follicular volume were associated with anovulatory cycles. Subfollicular VI and VFI might be used as markers of follicular quality and pregnancy predictors.

Temporal relationships of the LH surge and ovulation to echotexture and power Doppler signals of blood flow in the wall of the preovulatory follicle in heifers

Changes in echotexture and blood flow in the wall of preovulatory follicles in heifers were studied in relation to the LH surge and ovulation in gonadotrophin-releasing hormone-induced (n = 7; Experiment 1) and spontaneous (n = 8; Experiment 2) ovulators. Ultrasonographic examinations and blood sampling were performed either every hour (Experiment 1) or every 6 h (Experiment 2). The interval from LH peak to ovulation in induced and spontaneous ovulators was 27.1 ± 0.3 and 34.5 ± 1.5 h, respectively. Follicle diameter did not increase between the LH peak and ovulation. In the induced ovulators, serration of the stratum granulosum was detected in one (14%), two (29%), three (43%) and four (57%) heifers at 4, 3, 2 and 1 h before ovulation, respectively. An initial increase in blood flow (P < 0.001) encompassed the LH peak in both experiments. In the induced ovulators, blood flow increased (P < 0.02) to maximum 3 h after the LH peak, maintained a plateau for 5 h, decreased (P < 0.05) between 9 and 14 h, increased (P < 0.05) again between 19 and 21 h and then decreased (P < 0.01) between 25 and 26 h (1 h before ovulation). The biphasic increase and decrease in blood flow and serration of the granulosum in the wall of the preovulatory follicle in cattle are novel findings.

Relationship of vascular perfusion of the wall of the preovulatory follicle to in vitro fertilisation and embryo development in heifers

The effect of the extent of vascular perfusion of the wall of the preovulatory follicle on in vitro cleavage rate of the recovered oocyte and embryo development to >8 cells was studied in 52 heifers. Heifers received a luteolytic dose of prostaglandin F2α (PGF2α) when the largest follicle was ≥11 mm. An ovulation-inducing injection of GnRH was given 36 h later (hour 0), and collection of follicular fluid and the oocyte was done at hour 26. Vascular perfusion of the follicular wall was assessed by colour Doppler ultrasonography at hours 0 and 26. Each of the recovered oocytes (41/52; 79%) was mature (extruded polar body). Cleavage and embryo development were assessed at 48 h and 120 h respectively, after in vitro fertilisation (IVF). The percentage of cleaved oocytes and >8 cell embryos was 80% (31/39) and 55% (17/31) respectively. Vascular perfusion of the follicular wall was greater (lower pulsatility index; P<0.001) for follicles that produced cleaved versus non-cleaved oocytes and greater (P<0.04) for follicles that produced >8 cell versus ≤8 cell embryos. Percentage of follicular wall with Doppler signals of blood flow was greater (P<0.001) for >8 cell versus ≤8 cell embryos. Follicular-fluid concentration of free IGF1 was lower for cleaved oocytes (P<0.001) and >8 cell embryos (P<0.05), and oestradiol was lower (P<0.05) for >8 cell embryos. Results supported the hypothesis that greater vascular perfusion of the wall of the preovulatory follicle was positively associated with IVF and embryo development.

Genital blood flow and endometrial gene expression during the preovulatory period after Prostaglandin F(2alpha)-induced luteolysis in different luteal phases in cows

The aim of this study was to examine the hypothesis that follicular and uterine perfusion as well as endometrial gene expression during the ovulatory period differs after induction of luteolysis during the 1(st) follicular wave compared with the 2(nd) wave or in intact cycle. Nine healthy non-lactating Holstein-Friesian cows were examined during three estrous cycles. A prostaglandin F(2alpha) analogue (PGF) was administered randomly either on Day 7 (1(st) wave cycle) or Day 11 (2(nd) wave cycle) after detection of ovulation (=Day 1). No hormonal treatment was used in the intact cycle with spontaneous ovulation. Transrectal Doppler sonography was conducted daily after PGF injection and in the intact cycle beginning on Day 18 of the estrous cycle until ovulation. Follicular blood flow (FBF) was determined by measuring the maximum area of colour pixels on digitalized images of the follicles. Uterine blood flow was quantified by the time-averaged maximum velocity (UTAMV) and pulsatility index (PI) in both uterine arteries. Blood flow measurements were carried out on Days -1 and 0. Endometrial biopsy specimens were taken on Day 1 and analyzed for the gene expressions of estrogen, progesterone, oxytocin and VEGF receptors and eNOS and iNOS using RT-PCR. The interval from PGF injection to ovulation was shorter (P<0.05) in 1(st) wave cycles than in 2(nd) wave cycles. On Days 0 and -1, FBF was greater (P<0.05) in 1(st) wave cycles than in intact and 2(nd) wave cycles. On Day -1, UTAMV was greater (P<0.05) in 1(st) wave cycles than in intact and 2(nd) wave cycles. There were no differences (P>0.05) in FBF and UTAMV values between 2(nd) wave and intact cycles. No differences (P>0.05) were detected in the gene expressions of endometrial receptors and enzymes between intact, 1(st) and 2(nd) wave cycles. The results show that follicular and uterine perfusion during the ovulatory phase are higher after induction of luteolysis during the 1(st) follicular wave compared with the 2(nd) wave or intact cycle. There were no effects on endometrial gene expression.

Morphological selection of gametes

Methods of selecting gametes before the intracytoplasmic sperm injection (ICSI) technique are of paramount importance, especially where for religious, ethical or legal reasons the production of supernumerary embryos has to be avoided. In these circumstances, in fact, the research has to be focused on the identification of early markers of embryo quality at the oocyte and sperm stage before fertilisation. Oocyte quality can be influenced by several factors such as controlled ovarian hyperstimulation protocols, pharmaceutical preparations and perifollicular vascularisation. Several intracytoplasmic and extracytoplasmic abnormalities have been described, but whether these abnormalities might be predictive of oocyte competence is controversial and the selection methods proposed are still poorly effective. Recently, we have observed that oocyte morphological abnormalities might be indicators of oocyte competence. An abnormal first polar body (but not fragmented), a large perivitelline space, increased cytoplasmic granularity, and the presence of a centrally located granular area seem to have a negative effect on the oocyte potential to fertilise, cleave, and/or develop into a viable embryo. Sperm morphology can be more accurately observed at high magnification using an inverted microscope equipped with Normarski optics (1000x magnification under mineral oil) and a digital system in order to reach a final magnification of approximately 6300x. Single sperm nuclear abnormalities based on strict selection criteria seems to have a clear negative association with ICSI outcome. The possibility of observing the spermatozoa in real time at higher magnification might also be a good opportunity to study the relationship between particular sperm defects and ICSI outcome. In addition to morphology, it has been suggested that spermatozoa selection might be performed on the basis of its biochemical ability to bind to solid hyaluronic acid. However, it must be underlined that prospective randomised studies are necessary to confirm the preliminary results regarding the efficacy of the described criteria proposed, to morphologically select gametes prior to in vitro insemination.

Is it possible to predict a fertile cycle? Uteroovarian blood flow parameters in conception versus nonconception cycles

OBJECTIVE

To compare uterine and ovarian blood flow, measured by Doppler ultrasound, in the follicular phase of the menstrual cycle, in women who conceived to women who did not conceive during that cycle.

DESIGN

A prospective study of 192 women looking at markers of ovarian reserve between August 2000 and September 2002.

SETTING

A fertility clinic.

PATIENT(S)

A cross-section of women attending for fertility advice and treatment.

INTERVENTION(S)

Each woman was monitored during a natural cycle and then during a clomiphene challenge cycle (100 mg clomiphene given for 5 days from days 3-7 of the cycle). Doppler ultrasound scans were performed on days 3 and 12 of the natural cycle and day 11 of the clomiphene challenge cycle.

MAIN OUTCOME MEASURE(S)

Cycles in which women conceived were compared with those in which women did not conceive to see whether there were differences in uteroovarian blood flow parameters as measured by Doppler ultrasound scan in the follicular phase of the cycle.

RESULT(S)

In the 15 natural conception cycles there was an increased uterine artery peak systolic velocity at day 12 compared with 131 natural nonconception cycles (in which there was an opportunity to conceive). There were no differences in any uteroovarian blood flow parameters at day 3, and no differences in ovarian blood flow parameters (dominant follicle blood flow, dominant follicle pulsatility index), endometrial thickness or pulsatility at day 12. No differences were seen in any blood flow parameters in 10 clomiphene conception cycles compared with 116 clomiphene nonconception cycles.

CONCLUSION(S)

In the late follicular phase of natural conception cycles there is an increased uterine artery peak systolic velocity compared with nonconception cycles. This was not seen in clomiphene cycles in which conception occurred. There is very little in the literature comparing natural or clomiphene conception with nonconception cycles.

Application of Doppler Ultrasonography in Cattle Reproduction

The development of Doppler processing extended the scope of sonographic imaging from an anatomical to a physiological basis. This technique became established as a clinical tool in human gynaecology. For example, it has been discussed that the implantation of an embryo is influenced by the uterine blood flow. In cows, this uterine blood flow was investigated, using surgically implanted Doppler ultrasonic or electromagnetic blood flow probes prior to the introduction of colour Doppler sonography in bovine medicine. Therefore, the aims of our studies were to use transrectal Doppler sonography for the non-invasive measurement of uterine and ovarian blood flow in cows and to determine changes in genital perfusion during the oestrous cycle, pregnancy and puerperium, respectively. The results of our studies show that transrectal flow imaging can be used to obtain blood flow velocity waveforms from the uterine arteries at any time during the oestrous cycle, pregnancy and puerperium. During all these phases, characteristic changes in the uterine blood flow could be observed. This uterine blood flow was low during diestrus and high during proestrus and oestrus. During pregnancy, an exponential rise in uterine blood supply could be detected. There was a positive relationship between the uterine blood flow volume (BFV) at the end of gestation and the birth weight of calves. During puerperium, the uterine BFV declined tremendously, especially during the first week after birth. In cows, with pathological disturbances of the pueperium a delayed decrease in the uterine BFV was observed. Characteristic alterations occurred also in the luteal blood flow during the oestrous cycle, which were highly related to those of the progesterone levels. Furthermore, it has been detected by the colour Doppler technique that there is no decrease, but an increase of the luteal blood flow at the beginning of luteolysis in cows. Another group has found that there are close relationships between the LH-surge and the follicular blood flow before ovulation. In conclusion, these studies show that transrectal colour Doppler sonography is a useful technique for the investigation of the genital blood flow and provides new information about physiological changes of the genital organs during, all reproductive phases. The influence of the genital blood flow on fertility in cows needs to be examined further in future studies.

Studies of Follicular Vascularity Associated with Follicle Selection and Ovulation in Cattle

We reviewed recent in vivo studies of the real-time changes in the vasculature of the follicle wall during selection of the dominant follicle as well as during ovulation in cows. Changes in follicle diameter and vascularity were determined by transrectal ultrasonography. Blood flow within the walls of the two largest follicles was detected at the time of wave emergence (largest follicle=5 mm in diameter). Before selection of a follicle (largest follicle <8.5 mm in diameter), the degrees of vascularity of the two largest follicles were not significantly different. After the largest follicle reached a diameter of 10 mm, the vascularity of the largest (dominant) follicle was higher than that of the second largest (subordinate) follicle. In the preovulatory follicle, follicular vascularity gradually increased, and as ovulation approached, the LH-surge induced an increase in blood flow within the follicle wall. The above results suggest that maintenance of follicular vasculature and appropriate blood supplies to follicles are essential for establishment of follicular dominance. Consequently, only a dominant follicle with high vascularity may have a chance to reach final maturation and acquire ovulatory capacity.

The 3D vascular status of the follicle after HCG administration is qualitatively rather than quantitatively associated with its reproductive competence

BACKGROUND

The objective of this study was to determine whether the vascular status of a single pre-ovulatory follicle is associated quantitatively and/or qualitatively with its reproductive competence.

METHODS

We studied 61 monofollicular IVF-embryo transfer cycles. Just before single oocyte retrieval, follicle vascularization was detected by transvaginal power-Doppler, 3-dimensionally reconstructed, and analysed quantitatively by coloured/gray voxel ratio [vascularization index (VI)] and qualitatively by blood cell displacement [flow index (FI)] calculation. Cycles were sorted in two sets of two groups: low VI (<or=8%, n = 44) and high VI (>8%, n = 17); low FI (<or=30, n = 22) and high FI (>30, n = 39).

RESULTS

Patients' characteristics, fertilization rates, and embryo morphology were comparable in all groups. In contrast, clinical pregnancy rates/oocyte retrieval (4% versus 33%, P < 0.009) and implantation rates (11% versus 50%, P < 0.04) were markedly poorer in the low as compared to the high FI groups, respectively, but remained similar between the low and the high VI groups (22% versus 23% and 38% versus 44%, respectively).

CONCLUSIONS

A qualitative (FI) rather than quantitative (VI) relationship exists between vascular status and functional quality of the follicle after HCG administration.

Reduction of perifollicular arterial blood flow resistance after hCG administration is a good indicator of the recovery of mature oocytes in ART treatment

PURPOSE

To demonstrate our hypothesis that a correlation exists between oocyte maturity and a decrease in intraovarian blood flow resistance in assisted reproductive technology (ART) treatment cycles, oocyte maturity and total antioxidant status (TAOS) in follicular fluid was examined.

METHODS

A total of 59 cycles involving 51 infertile patients undergoing ART treatment in our hospital were recruited in this study. The ART cycles were divided into two groups: deeply decreased (DD) group and not-deeply decreased (NDD) group, according to the pulsatility index (PI) values for perifollicular arterial blood flow before and after hCG administration. The PI values that showed a decrease in their PI after hCG administration of 10% or more were defined "deeply decreased" and showed a decrease of less than 10% were considered "not-deeply decreased." The recovery rates of mature and immature oocytes and TAOS in follicular fluid were compared between the two groups.

RESULTS

Mature and immature oocyte recovery rates in the DD group (62.5% and 17.2%) were significantly higher and lower, respectively, than those in the NDD group (41.7% and 38.3%, p < 0.05). The TAOS (1.55 +/- 0.44 mmol/L) of the DD group was significantly lower than that in the NDD group (1.68 +/- 0.47 mmol/L, p < 0.05).

CONCLUSIONS

The decrease in intraovarian arterial blood flow resistance measured after hCG administration may be a good indicator of retrieving mature oocyte.

Quality of reporting of test accuracy studies in reproductive medicine: impact of the Standards for Reporting of Diagnostic Accuracy (STARD) initiative

OBJECTIVE

To evaluate the extent to which test accuracy studies published in two leading reproductive medicine journals in the years 1999 and 2004 adhered to the Standards for Reporting of Diagnostic Accuracy (STARD) initiative parameters, and to explore whether the introduction of the STARD statement has led to an improved quality of reporting.

DESIGN

Structured literature search. Articles that reported on the diagnostic performance of a test in comparison with a reference standard were eligible for inclusion. For each article we scored how well the 25 items of the STARD checklist were reported. These items deal with the study question, study participants, study design, test methods, reference standard, statistical methods, reporting of results, and conclusions. We calculated the total number of reported STARD items per article, summary scores for each STARD item, and the average number of reported STARD items per publication year.

SETTING

Not applicable.

PATIENT(S)

Not applicable.

INTERVENTION(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

Quality of reporting.

RESULT(S)

We found 24 studies reporting on test accuracy in reproductive medicine in 1999 and 27 studies in 2004. The mean number of reported STARD items for articles published in 1999 was 12.1 +/- 3.3 (range 6.5-20) and 12.4 +/- 3.2 (range 7-17.5) in 2004, after publication of the STARD statement. Overall, less than half of the studies reported adequately on 50% or more of the STARD items. The reporting of individual items showed a wide variation. There was no significant improvement in mean number of reported items for the articles published after the introduction of the STARD statement.

CONCLUSION(S)

Authors of test accuracy studies in the two leading fertility journals poorly report the design, conduct, methodology, and statistical analysis of their study. Strict adherence to the STARD guidelines should be encouraged.

The role of oxygen in ruminant preimplantation embryo development and metabolism

The long-term effects of in vitro embryo culture on animal health are presently unknown, however, current knowledge directs investigations toward understanding the mechanisms involved in regulating embryo development. In vitro culture is known to have short-term effects, particularly on gene expression and metabolism at the blastocyst stage, while large offspring syndrome is commonly observed following transfer of in vitro produced bovine embryos. Indeed, it is likely that the environment surrounding the early embryo, prior to implantation, may program later development. Regulation of gene expression and metabolism, through gene activation, is mediated by transcription factors, which are themselves controlled by internal and external factors. Alterations in the surrounding environment during preimplantation embryo development, such as that which occurs with inadequate developmental 'support' during in vitro culture, may modify the activation, or inactivation, of several transcription factors, and may therefore have long-term consequences for the developing offspring. In vitro culture deviates from in vivo conditions in many respects, but one of the critical factors that is generally not considered is the oxygen tension under which embryos are cultured. Numerous studies have demonstrated that atmospheric oxygen conditions during culture have detrimental effects on embryo development. While it is generally believed that this arises from the production of reactive oxygen species, this presents an over-simplistic view of the role of oxygen during development. The hypoxia-inducible factor transcription factor family is involved in the responses of cells to alterations in external oxygen concentrations, regulating the expression of numerous genes. Alterations in expression of some of these genes have been highlighted by recent studies in the bovine embryo, implicating oxygen as a regulator of several cellular and metabolic pathways. While it is clear that oxygen plays a role during embryo development, further work to investigate interactions between oxygen and other signaling pathways such as pH and Ca(2+), mitochondria and metabolism is required, as well as exposure of embryos at different time points, to determine the mechanisms that control preimplantation development, the interactions of a range of stimuli and to establish culture procedures that support optimal development and minimize risks to health. This review focuses largely on work undertaken in ruminant models, with brief references to other species.

Power doppler ultrasound assessment of the relationship between age and ovarian perifollicular blood flow in women undergoing in vitro fertilization treatment

PURPOSE

To examine the relationship between age and ovarian perifollicular blood flow (PFBF) in women undergoing IVF.

METHODS

Serial transvaginal power Doppler ultrasound (PDU) scans to assess ovarian PFBF were performed prospectively throughout the follicular phase of ovarian stimulation in women undergoing IVF. The ultrasound assessment days were categorized according to day of hCG trigger.

RESULTS

A total of 1050 ovarian follicles from 34 women undergoing one IVF treatment cycle were used for data analysis. The median age of the women was 38.5 years, ranging from 28 years to 44 years. There was a significant negative correlation between age and ovarian PFBF on the day of hCG trigger or trigger day minus 1, but not beforehand during the follicular phase.

CONCLUSIONS

There was a significant negative correlation between age and ovarian PFBF in women undergoing IVF which was only observed very late in the follicular phase of ovarian stimulation.

Follicular vascularity is not predictive of pregnancy outcome in mild controlled ovarian stimulation and IUI cycles

BACKGROUND

Although follicular vascularity has been shown to be a good indicator of oocyte quality in IVF, scant evidence is currently available on the predictive value of this variable in terms of pregnancy rate during controlled ovarian stimulation (COS) and intrauterine insemination (IUI) cycles.

METHODS

Three-hundred and eighteen patients who had received mild COS underwent transvaginal ultrasound scan before performing the IUI. Using power Doppler imaging, vascularity of follicles with a mean diameter > or =16 mm was graded into a three grades according to the circumference of the follicle in which flow was identified. When more than one follicle was observed, grading was performed for all of them, and the highest vascularity grade was recorded.

RESULTS

Clinical pregnancy rate (number/total) in the low-, medium- and high-grade vascularity groups was 14.1% (14/99), 10.0% (10/100) and 11.8% (14/119), respectively (P = 0.66). Similar results were observed when only monofollicular cycles were considered.

CONCLUSIONS

Follicular vascularity does not predict the chance of pregnancy in women undergoing mild COS and IUI cycles.

Assessment of changes in volume and vascularity of the ovaries during the normal menstrual cycle using three-dimensional power Doppler ultrasound

BACKGROUND

Our aim was to describe changes in the volume and vascularization of both ovaries, the dominant follicle and the corpus luteum during the normal menstrual cycle using three-dimensional (3D) power Doppler ultrasound.

METHODS

Fourteen healthy volunteers underwent serial transvaginal 3D ultrasound examinations of both ovaries on cycle day 2, 3 or 4, then daily from cycle day 9 until follicular rupture and 1, 2, 5, 7 and 12 days after follicular rupture. The volume and vascular indices of the ovaries, the dominant follicle and the corpus luteum were calculated off-line using virtual organ computer-aided analysis (VOCAL) software.

RESULTS

The volume of the dominant ovary increased during the follicular phase, decreased after follicular rupture and then increased again during the luteal phase. Vascular indices in the dominant ovary and the dominant follicle/corpus luteum increased during the follicular phase, the vascular flow index (VFI) in the dominant follicle being on average (median) 1.7 times higher on the day before ovulation than 4 days before ovulation (P=0.003). The vascular indices continued to rise after follicular rupture so that VFI in the corpus luteum was on average (median) 3.1 times higher 7 days after ovulation than in the follicle on the day before ovulation (P=0.0002). The volume and vascular indices in the non-dominant ovary manifested no unequivocal changes during the menstrual cycle.

CONCLUSIONS

Substantial changes occur in volume and vascularization of the dominant ovary during the normal menstrual cycle. 3D power Doppler ultrasound may become a useful tool for assessing pathological changes in the ovaries, for example, in subfertile patients.

Power Doppler ultrasound assessment of follicular vascularity in the early follicular phase and its relationship with outcome of in vitro fertilization

OBJECTIVE

To determine whether ovarian perifollicular blood flow (PFBF) in the early follicular phase (EFP) was associated with treatment outcome.

DESIGN

Retrospective longitudinal cohort study.

SETTING

Tertiary referral centre/university hospital.

PATIENTS

Thirty-four women underwent 37 IVF cycles, which resulted in 35 embryo transfers.

INTERVENTIONS

Serial transvaginal scans using power Doppler ultrasound during the follicular phase. Ovarian PFBF of follicles > or =5 mm was subjectively assessed using a modified grading system (grades 0-4).

MAIN OUTCOME MEASURES

Ovarian PFBF and pregnancy.

RESULTS

Treatment cycles were retrospectively divided into two groups: Group 1 (n=20) had cycles with at least one small (5-10 mm) or medium (11-14 mm) size follicle(s) of high grade (2-4) PFBF on cycle day 5 or 6 or 7; and Group 2 (n=17), had cycles that did not. Group 1 had a significantly higher proportion of high grade large follicles in the late follicular phase (35% vs. 21%) (OR 2.0; 95% CI 1.1-3.7) and higher clinical pregnancy rate (47% vs. 12%) (OR 6.3; CI 1.1-35.7) compared to Group 2.

CONCLUSION

High grade ovarian PFBF in the EFP during IVF is associated with both high grade PFBF in the late follicular phase and a higher clinical pregnancy rate.

Relationships of changes in B-mode echotexture and colour-Doppler signals in the wall of the preovulatory follicle to changes in systemic oestradiol concentrations and the effects of human chorionic gonadotrophin in mares

A duplex grey-scale and colour-Doppler ultrasound instrument was used to study the changes in the wall of the preovulatory follicle in mares. When the follicle reached ≥35 mm (hour 0), mares were randomized into control (n= 16) and human chorionic gonadotropin (hCG)-treated (n= 16) groups. The hCG treatment was given at hour 0. Scanning was done every 12 h until hour 36, every hour between hours 36 and 48, and every 12 h thereafter until ovulation. Blood was sampled every 12 h for oestradiol assay. During the period 0–24 h post-treatment, oestradiol concentrations decreased in the hCG group and increased in the controls (significant interaction). During the period 0–36 h post-treatment, thickness and echogenicity of the granulosa increased in the hCG group but not in the controls. During the period 36 to 12 h before ovulation, granulosa and colour-Doppler end-points increased in the control and hCG groups (hour effects), while oestradiol was decreasing in both groups. The prominence and percentage of follicle circumference with an anechoic band peripheral to the granulosa and colour-Doppler signals in the follicle wall, indicating arterial blood flow, decreased during the period 4 to 1 h before ovulation (hour effects). Results indicated that the ultrasonographic changes of the wall of the preovulatory follicle were not associated temporally with changes in oestradiol concentrations and prominence of an anechoic band, and colour-Doppler signals decreased during the few hours before ovulation. The hypothesis that the latter portion of the ovulatory LH surge has a negative effect on systemic oestradiol was supported by the immediate decrease in oestradiol concentrations when hCG was injected.

Assessment of the ovarian volume, number and volume of follicles and ovarian vascularity by three-dimensional ultrasonography and power Doppler angiography on the HCG day to predict the outcome in IVF/ICSI cycles

OBJECTIVE

The aim of this prospective study was to investigate whether ovarian blood flow is related to embryological parameters and whether it could be a predictor of outcomes of IVF/ICSI.

METHODS

Eighty infertile women underwent ovarian stimulation with gonadotrophins after a long protocol with GnRH agonists. The ovarian volume (OV), number of follicles (NF) and follicular volume (FV) of all follicles >10 mm and vascularization index (VI), flow index (FI) and vascularization-flow index (VFI) were obtained by three-dimensional (3D) ultrasonography and power Doppler angiography (PDA) on the day of HCG administration. These parameters were tested for their relation with IVF laboratory parameters.

RESULTS

The OV, FV, VI, FI and VFI were significantly greater in the pregnant group. The NF and FV were the only independent predictors of the number of oocytes retrieved, mature and fertilized, and the number of embryos developed and their cumulative embryo score. Nevertheless, the number of grade 1 embryos depends on the NF and the VI. The ovarian FI and the number of transferred grade 1 embryos can predict gestation in 76% of IVF patients. A low FI and non-grade 1 embryo transferred are also associated with an increased pregnancy loss.

CONCLUSION

3D ultrasonography and PDA allow for an easier ovarian assessment in IVF cycles. The predictive value of IVF outcome suggests a high clinical usefulness of this new technique.

Clinical use of the perifollicular vascularity assessment in IVF cycles: a pilot study

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.

Predictivity of uterine artery, arcuate artery, and intraovarian artery Doppler indices measured on the day of human chorionic gonadotropin injection on pregnancy outcomes

The uterine, arcuate, and intraovarian blood flow measurements by transvaginal color doppler ultrasonography on the day of hCG injection in 46 women undergoing treatment by IVF at Aegean University Family Planning and Infertility Research and Treatment Center were evaluated. In the pregnant group, average uterine and arcuate arteries blood flow resistance values were lower than those in nonpregnant women.

Changes in Follicular Vascularity during the First Follicular Wave in Lactating Cows

Increase in the blood supply to individual follicles appears to be associated with follicular growth rates and the ability to become the dominant follicle, while reduced thecal vascularity appears to be closely associated with follicular atresia. Therefore, this study aimed to determine the real-time changes in the vascularity of the follicle wall during the first follicular wave in cycling Holstein cows. Normally cycling and lactating cows (n=5) were examined by transrectal color Doppler ultrasonography (the sensitivity for velocity: > 2 mm/sec) to determine the changes in the vasculature of the follicle wall (presence or absence of blood flow) and the diameter of follicles. A new follicular wave and ovulation were induced by GnRH injection at 48 h after an injection of PGF2alpha analogue. The ovaries were scanned daily for 7 days after GnRH injection. Follicles >2.5 mm were classified into 3 groups by the changes in diameter as follows: 1) largest follicle, 2) second largest follicle, and 3) small follicles, which included all other follicles >2.5 mm. Before the follicle selection, there was no significant difference in the percentage of follicles with detectable blood flow between the subsequently determined largest and second largest follicles. After the follicle selection, the percentage of follicles with detectable blood flow significantly decreased among the second largest follicles. In addition, small follicles with detectable blood flow kept larger diameters than those without detectable blood flow from one day before the occurrence of follicle selection. It is likely that maintenance of follicle vasculature and appropriate blood supply to the larger follicles is essential for follicle dominance. In small follicles, the presence of blood flow within the wall also appears to be required for recruitment. Consequently, the data suggest that the change of the blood supply to an individual follicle closely relates to the dynamics of follicular growth in the first follicular wave in the cow.

Comparison of follicular vascularization in normal versus polycystic ovaries during in vitro fertilization as measured using 3-dimensional power Doppler ultrasonography

OBJECTIVE

The growth of the follicles induced by gonadotropins during IVF treatment is accompanied by physiologic angiogenesis, which is essential for the maturation of the oocytes. We describe the IVF-induced changes in the vascularization and compare normal with polycystic ovaries (PCOs).

DESIGN

Prospective study.

SETTING

Assisted reproductive unit at a university hospital.

PATIENT(S)

Sixty women who underwent IVF cycles.

INTERVENTION(S)

The ovarian vascularization was measured after pituitary down-regulation, FSH stimulation, and hCG-injection using three-dimensional power Doppler ultrasonography.

MAIN OUTCOME MEASURE(S)

The total ovarian vascularization was divided by the number of follicles.

RESULT(S)

After pituitary suppression, the ovarian vascularization/follicle was lower in polycystic ovary (PCO) patients. During ovarian stimulation, follicles in PCOs required a lesser amount of FSH to acquire the same level of vascularization than the follicles in normal ovaries. In addition, hCG induced an increase in the follicular vascularization in both normal and PCOs. The follicle count correlated with the total vascularized volume in the ovaries throughout the IVF cycle.

CONCLUSION(S)

Follicles in PCOs seem to be less vascularized than the follicles in normal ovaries after GnRH treatment but not after gonadotropin stimulation. It is possible that restricted blood supply to the follicles in PCO might be associated with the follicular arrest that is observed. We could confirm that follicles in PCO are more sensitive to gonadotropin stimulation than follicles in normal ovaries.

Longitudinal assessment of ovarian perifollicular and endometrial vascularity by power Doppler ultrasound in pregnant and non-pregnant cycles in the IVF setting

PURPOSE

This longitudinal study aimed to compare ovarian perifollicular and endometrial blood flow (PFBF and EBF, respectively) during the follicular phase in pregnant and non-pregnant IVF cycles.

METHODS

Serial transvaginal scans were performed in 15 subjects undergoing IVF treatment. Both PFBF and EBF were subjectively graded (grades 0-4 for PFBF and grades 1-3 for EBF). After confirmation of clinical pregnancy, the treatment cycles were grouped into 'Pregnant' and 'Non-pregnant' cycles. Ovarian PFBF and EBF were retrospectively compared between the two groups.

RESULTS

In pregnant cycles, the proportion of large (> or = 15 mm) follicles with high (24) grade PFBF increased with time throughout the follicular phase, and the proportion of large follicles with poor (0-1) grade PFBF decreased. In non-pregnant cycles these trends were reversed. There was no difference in EBF between the two groups.

CONCLUSION

The pattern of ovarian PFBF but not EBF may be predictive of treatment outcome.

Aberrant Blood Flow Area and Plasma Gonadotropin Concentrations During the Development of Dominant-Sized Transitional Anovulatory Follicles in Mares1

Color Doppler transrectal ultrasound was used to evaluate blood flow area in the wall of dominant anovulatory follicles versus ovulatory follicles in mares during the transition between anovulatory and ovulatory seasons. Daily examinations were done in 11 control mares toward the end of the anovulatory season. In 13 separate mares, follicular fluid was collected from 30-mm follicles, and blood flow areas from control mares were used as a basis for designating the sampled follicle as either anovulatory or ovulatory. Blood flow area in the controls ranged from 0.18 to 0.35 cm(2) in six mares on the day of a 30-mm anovulatory follicle and from 0.25 to 0.86 cm(2) in 11 mares on the day of a 30-mm ovulatory follicle; the ranges did not overlap except for one follicle. In the controls, mean blood flow area was lower (P < 0.05) in the anovulatory group than in the ovulatory group for each day beginning with the first Doppler examination at 25 mm. For plasma LH in controls, an effect of follicle group (P < 0.0001) and an interaction (P < 0.0001) of group by day reflected lower (P < 0.05) concentrations in the anovulatory group on Days -6, -2, and 5-8 (Day 0 = 30-mm follicle). For plasma FSH, an interaction (P < 0.0001) reflected higher (P < 0.05) concentrations in the anovulatory group on Days -3 and 1-4. More (P < 0.05) statistically identified FSH surges occurred in the anovulatory group during Days -7 to 8. In the sampled mares, follicular-fluid concentrations of estradiol, free insulin-like growth factor-1, inhibin-A, and vascular endothelial growth factor were lower (P < 0.05) in 30-mm designated anovulatory follicles than in 30-mm designated ovulatory follicles. Results were interpreted as follows: 1) The future anovulatory dominant-sized follicle developed under an LH deficiency, 2) the LH deficiency led to reductions in blood flow area and in concentrations of follicular-fluid factors, and 3) the reduction in follicle production of FSH suppressors resulted in higher plasma FSH concentrations.

Differential Blood Flow Changes Between the Future Dominant and Subordinate Follicles Precede Diameter Changes During Follicle Selection in Mares1

Diameter deviation during a follicular wave is characterized by the continued growth of the developing dominant follicle and reduced growth and regression of the subordinate follicles. This study considered the hypothesis that reduced blood flow in the future largest subordinate follicle precedes the beginning of diameter deviation. The hypothesis was tested by quantifying the daily changes in blood-flow velocities and blood-flow area within the wall of follicles before and during diameter deviation in mares (n = 7). The blood-flow end points were quantified daily by transrectal color Doppler ultrasonography. Follicles were identified retrospectively by rank as F1 (largest) and F2 according to the maximum attained diameter. Follicles were grouped into nine F1 diameter ranges of 3.0 mm each (equivalent to 1 day's growth) centered on 6.5, 9.5, 12.5, 15.5, 18.5, 21.5, 24.5, 27.5, and 30.5 mm. Diameter deviation began in the 24.5-mm group, as indicated by a smaller (P < 0.05) difference between F1 and F2 in the 24.5-mm group than in the 27.5-mm group. Based on a similar approach, peak systolic velocity and time-averaged maximum velocity of blood flow began to deviate between F1 and F2 in the 18.5-mm group (P < 0.04) and blood flow area began to deviate in the 21.5-mm group (P < 0.009). Thus, differential blood flow area between F1 and F2 began an average of 3.0 mm (equivalent to 1 day) and differential blood-flow velocities began an average of 6.0 mm before the beginning of diameter deviation. The results demonstrated that deviation between F1 and F2 in the blood flow of the follicle walls occurred 1 or 2 days before deviation in follicle diameter during follicle selection in mares.

Role of utero–ovarian vascular impedance: predictor of ongoing pregnancy in an IVF–embryo transfer programme

The objective of this study was to evaluate the role of uterine, endometrial and follicular blood flow in prediction of ongoing pregnancy after assisted conception. A prospective observational study was conducted on 53 women undergoing IVF treatment. Transvaginal colour and pulsed Doppler measurements were performed on the day that pituitary suppression was confirmed, on day 10 of ovarian stimulation and on the day prior to human chorionic gonadotrophin injection. On the last day of ovarian stimulation, blood flow in the ascending uterine artery of the women who would conceive was characterized by significantly lower pulsatility index values. Sub-endometrial vascular impedance was comparable in the pregnant and non-pregnant groups. There were no differences in the perifollicular vascularity between pregnant and non-pregnant women. The chance of achieving pregnancy predicted by uterine artery Doppler and perifollicular blood flow in women whose PI values were higher than 3.26 and 1.08 was very low, with a sensitivity of 1.00 and specificity of 0.59 and 0.82 respectively. The data provide evidence for an association between utero-ovarian perfusion and reproductive outcome following IVF treatment. Uterine and ovarian vascular impedance values identify those women whose pregnancy chances are significantly limited. Measures to decrease vascular impedance in such women might enhance pregnancy rates by improving embryo quality and uterine receptivity for implantation.

Measurement of perifollicular blood flow of the dominant preovulatory follicle using three-dimensional power Doppler

OBJECTIVE

To establish whether we might predict the outcome of unstimulated in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) cycles with quantitative indices of perifollicular blood flow assessed with three-dimensional (3D) reconstruction of power Doppler images.

METHODS

This prospective study included an analysis of 52 unstimulated cycles. Color and power Doppler ultrasound examinations of a single dominant preovulatory follicle were performed on the day of oocyte pick-up. With 3D reconstruction and processing, quantitative indices were obtained i.e. the percentage of volume showing a flow signal (VFS) inside a 5-mm capsule of perifollicular tissue and the percentage of VFS of each of the three largest vessels in this capsule. These indices as well as pulsed Doppler indices were compared between the groups of cycles with different outcomes using a one-way ANOVA test.

RESULTS

In nine cycles no oocyte was retrieved (Group A), in seven cycles no fertilization occurred (Group B) and in 30 cycles no implantation occurred (Group C). Six cycles resulted in pregnancy (Group D). There were no statistically significant differences in pulsed and power Doppler indices between these groups. However, the percentage of VFS in the capsule was higher than average in cycles with implantation (19.22 +/- 16.82 vs. 12.42 +/- 8.89, NS) and the percentage of VFS in the main vessel exhibited lower than average values in cycles with implantation (20.66 +/- 10.05 vs. 39.84 +/- 20.15), but only reached borderline statistical significance (F = 2.457, P = 0.074).

CONCLUSION

It can be hypothesized that the follicles containing oocytes able to produce a pregnancy have a distinctive and more uniform perifollicular vascular network.