Follicular Blood Research Articles

Effect of different housing conditions on several indices of blood redox status and on reproductive performance in buffalo cows

The aim of the present study was to examine the effect of two different housing conditions on blood and follicular redox status and on reproductive performance of buffalo cows. Fifty buffalo cows were housed at a density of 13.3 m2/head, and fifty were housed at 27.0 m 2/head. Forty buffaloes for each group were inseminated, and blood samples were collected 45 days after AI. Ten buffaloes, for each group, were not inseminated, and follicular fluids and blood samples were collected at the time of ovulation. Titres of retinol, α-tocopherol, ascorbate, N-tyrosine and protein bound carbonyls were measured. No differences were found between the two groups. Redox status of pregnant, not pregnant and cows with embryo mortality was evaluated. We found no significant differences among the groups, thus suggesting that the outcome of fertilization might not depend only on the blood parameters evaluated. Our results demonstrate that the two different housing conditions do not affect plasma and follicular redox status.

Effects of nerve growth factor (NGF) on blood vessels area and expression of the angiogenic factors VEGF and TGFbeta1 in the rat ovary

BackgroundAngiogenesis is a crucial process in follicular development and luteogenesis. The nerve growth factor (NGF) promotes angiogenesis in various tissues. An impaired production of this neurotrophin has been associated with delayed wound healing. A variety of ovarian functions are regulated by NGF, but its effects on ovarian angiogenesis remain unknown. The aim of this study was to elucidate if NGF modulates 1) the amount of follicular blood vessels and 2) ovarian expression of two angiogenic factors: vascular endothelial growth factor (VEGF) and transforming growth factor beta 1 (TGFbeta1), in the rat ovary.ResultsIn cultured neonatal rat ovaries, NGF increased VEGF mRNA and protein levels, whereas TGFbeta1 expression did not change. Sectioning of the superior ovarian nerve, which increases ovarian NGF protein content, augmented VEGF immunoreactivity and the area of capillary vessels in ovaries of prepubertal rats compared to control ovaries.ConclusionResults indicate that NGF may be important in the maintenance of the follicular and luteal vasculature in adult rodents, either indirectly, by increasing the expression of VEGF in the ovary, or directly via promoting the proliferation of vascular cells. This data suggests that a disruption on NGF regulation could be a component in ovarian disorders related with impaired angiogenesis.

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.

Follicular blood flow is a better predictor of the outcome of in vitro fertilization–embryo transfer than follicular fluid vascular endothelial growth factor and nitric oxide concentrations

To investigate the relationship between follicular blood flow and the follicular fluid vascular endothelial growth factor (VEGF) and nitric oxide (NO) concentrations and to determine which factor might be a better predictor of the outcome of IVF-ET. Prospective study. Academic research laboratory. Forty-seven cycles of IVF (tubal factor, 25 cycles; male factor, 22 cycles) at the infertility clinic of Pusan National University Hospital from February 2002 to June 2002. Follicular blood flow was estimated on the day of hCG administration. Each follicular fluid sample was collected at oocyte retrieval, and follicular fluid VEGF and NO concentrations were assessed. Follicular blood flow and follicular fluid VEGF and NO concentrations according to the age of patients, the cause of infertility, and pregnancy rate. Of 47 cycles, 18 (38.3%) cycles resulted in a pregnancy. Follicular blood flow was significantly higher in the pregnant group compared with the nonpregnant group, but there was no statistically significant difference in age and infertility cause. Follicular fluid concentrations of VEGF and NO did not show statistically significant differences in age, infertility cause, or pregnancy outcome. As the follicle size increases, the follicular blood flow and follicular fluid VEGF concentrations increased significantly but the follicular fluid NO concentrations decreased. There was no correlation between VEGF and NO concentrations in the follicular fluid by linear regression analysis. Our study showed that follicular blood flow was positively associated with the outcome of pregnancy. This is the first study to investigate the direct association of the follicular blood flow with pregnancy outcome after IVF-ET. These results suggest that follicular blood flow might be a more effective prognostic marker of the pregnancy outcome of IVF than follicular fluid VEGF or NO concentrations.

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.

Comparison of follicular blood flow and follicular fluid concentrations of vascular endothelial growth factor and nitric oxide as prognostic factors in the outcome of in vitro fertilization

Objectives: The aims of this prospective study were to investigate the relationship between the outcome of in vitro fertilization and follicular blood flow, ovarian blood flow, and the follicular fluid concentration of vascular endothelial growth factor and nitric oxide to determine whether these factors might be outcome predictors. Design: This study was performed in 47 cycles who underwent in vitro fertilization with tubal factor (25 cycles) and male factor (22 cycles) at infertility clinic of Pusan National University Hospital from Feb. 2002 to June 2002. Materials and Methods: Ultrasound images of follicular and ovarian blood flow were estimated on the day of hCG administration. Each follicular fluid (FF) was collected at the oocyte retrieval and FF concentrations of vascular endothelial growth factor (VEGF) and nitric oxide(NO) were assessed. FF VEGF concentrations were measured using an enzyme-linked immunosorbent assay (Quantikine Human VEGF Immunoassay, R&D Systems Inc., Minneapolis, MN, USA). FF concentrations of nitrite/nitrate were determined colorimetrically by the Griess reaction. The color reaction was allowed to develop for 5 min at room temperature, after which the absorbance at 540 nM was recorded. Results: Follicular blood flow was significantly increased in the pregnant group compared to the nonpregnant group. However, age, dosage of gonadotropin administered, estradiol on hCG day, the number of oocytes retrieved, fertilization rate, No. of embryos transferred, ovarian blood flow, and FF concentrations of VEGF and NO were not significantly different in two goups. There were no differences in any clinical and laboratory parameters including the number of oocytes retrieved, fertilization rate, No. of embryos transferred, pregnancy rate, FF concentrations of VEGF and NO, and follicular blood flow according to the causes of infertility or age. As folliclular size increases, follicular blood flow and FF concentration of VEGF concentration were increased, but FF concentration of NO were decreased. No correlation existed between FF concentrations of VEGF and NO. The number of oocytes retrieved, the number of mature oocytes, and fertilization rate were not correlated with ovarian blood flow and FF concentrations of VEGF and NO. Conclusions: These results suggest that follicular blood flow might be an effective prognostic marker of the pregnancy outcome of in vitro fertilization rather than FF concentrations of VEGF or NO, and demonstrate that follicular blood flow and FF concentration of VEGF and NO were correlated significantly with follicular size. However, these study do not show that age was correlated with FF concentrations of VEGF and NO, ovarian blood, or follicular blood flow.

Side of ovulation and its effects on uterine and ovarian stromal blood flow and reproductive hormones

ObjectiveEffect of the side of ovulation on uterine, ovarian, and follicular blood flow parameters and various hormone levels. DesignProspective, observational study. SettingFertility Clinic, St. George’s Hospital. Patient(s)Nineteen women with regular menstrual cycles. Intervention(s)Pulsed Doppler measurements and serum hormonal concentrations during midfollicular, periovulatory, and midluteal phase for three successive cycles. Main outcome measure(s)Doppler blood flow and serum hormones. Result(s)Doppler blood flow of the ovarian stroma and follicular and uterine arteries showed no differences in the three phases between the right and left sides. Left-side uterine peak systolic velocity (PSV) (right-side PSV, 31.51cm/s; left-side PSV, 37.38 cm/s) during the periovulatory phase tended to be higher in the nondominant ovary; however, this was not quite significant. The serum hormone concentration showed no significant differences. Conclusion(s)The side of ovulation did not influence the Doppler blood flow to the ovarian stroma or follicular and uterine arteries. The side of ovulation had no effect on serum FSH, LH, 17β-estradiol, P, inhibin A, or inhibin B levels.

Utility of color Doppler indices of dominant follicular blood flow for prediction of clinical factors in in vitro fertilization-embryo transfer cycles.

To investigate the relationship between color Doppler indices of dominant follicular blood flow and clinical factors in in vitro fertilization-embryo transfer cycles. This was a prospective study involving 26 patients completing a total of 33 in vitro fertilization cycles. Dominant follicular blood flow indices, peak systolic velocities, the resistance index and the pulsatility index were evaluated using transvaginal color Doppler. The indices were compared to the clinical outcomes of in vitro fertilization-embryo transfer. There was a significant correlation between dominant follicular peak systolic velocities and the number of oocytes retrieved, as well as the number of mature oocytes obtained. There was no significant correlation between dominant follicular resistance index or pulsatility index and the number of follicles > 10 mm in diameter, the number of oocytes retrieved or the number of mature oocytes. There were no significant differences between dominant follicular peak systolic velocities, resistance index or pulsatility index, and fertilization rate or the ratio of good quality embryos. However, significant differences were found between the number of oocytes retrieved, as well as the number of mature oocytes for those patients in which the peak systolic velocity was below 25 cm/s. Doppler assessment of dominant follicle blood flow alone is useful for predicting the number of retrievable oocytes. However, morphological quality of the embryo produced or the pregnancy rate cannot be predicted by this method.

Follicular microvasculature in the porcine ovary.

The microvasculature of porcine ovaries, with special regard to the follicles in the interstitial-stromal tissue, was studied by scanning electron microscopy (SEM) of vascular corrosion casts. Porcine ovaries displayed several coiled arteries in the hilus and many branches with small diameters and a tightly spiraling configuration in the cortical areas. However, small arterioles became straight before entering vascular complexes of follicles and finally divided into capillaries. Vascular baskets of various sizes (150-9,900 micro m in diameter) and architecture related to follicles in various developmental stages were observed in the ovarian cortex. Small follicles (150-300 micro m in diameter) began with a polygonal meshwork of a few large capillary meshes and developed to an obvious spherical microvascular network with a thin single layer of capillaries when reaching 500-700 micro m in diameter. The microvascular architecture of follicles 1,000-2,000 micro m in diameter developed further and had a three-layer vascular plexus. With a diameter of more than 2,000 micro m, the microvasculature of antral follicles was arranged as an inner vascular plexus of about 25 micro m, a middle plexus of about 100 micro m, and an outer capillary plexus of about 30 micro m in thickness. The present observations indicate that follicular vascular baskets of diverse sizes and architecture in various developmental stages support the gradual increase of follicular blood flow during follicle growth in the pig.

Effects of calcium salts of fatty acids on follicular characteristics and several blood parameters in two fat-tailed sheep breeds

There is substantial evidence that the increased consumption of fat by dairy cattle can result in an increase in the number ovarian follicles, and the number and size of corpora lutea; it also stimulates post-partum ovarian activity and improve pregnancy rate. Increased dietary lipid also increases plasma cholesterol and progesterone, and the supply of lipoproteins which play significant roles in regulating ovarian steroidogenesis (Willimas, 1996). In contrast to cattle, there are few observations on the effects of dietary lipid on reproductive function in sheep. Intravascular infusion of lipid into ewes stimulated progesterone and prostaglandin synthesis (Burke et al., 1996), and dietary supplementation of calcium soaps of fatty acids enhanced luteal function (Kuran et al., 1999). Calcium soaps of fatty acids have been manufactured in Iran in recent years and sold under the trade name of Megalac. The aim of the present experiment was to study the effects of this protected fat on follicular number and luteal activity in two fat-tailed sheep breeds.

Quantitative Real-Time Polymerase Chain Reaction for Detection of Circulating Cells with T(14;18) in Volunteer Blood Donors and Patients with Follicular Lymphoma

The chromosomal rearrangement t(14;18)(q32;21) involves the major (MBR) or minor (mcr) breakpoint cluster regions and the immunoglobulin heavy chain joining regions (JH) in most follicular lymphomas. As a first step towards determining the clinical significance of circulating cells with t(14;18), we detected and quantitated circulating cells in samples obtained from volunteer blood donors and follicular lymphoma patients. The t(14;18) was co-amplified with β -actin with real-time quantitative PCR (QRT-PCR) in reactions containing 1 µ g of DNA from peripheral blood or bone marrow aspirates. The cell number was quantitated using linear regression and an external standard of serially diluted DNA from cell lines with MBR/JH or mcr/JH rearrangements. At dilutions of 10 5 and 10 6, sensitivity was 100 and 55% for MBR/JH, and 100 and 10% for mcr/JH rearrangements. Among 102 volunteer blood donors MBR/JH vs. mcr/JH amplicons were detected in 22 vs. 4% with duplicate 1 µ g DNA reactions, and in 41 vs. 6% with a total 10 µ g DNA analyzed in multiple reactions. Among volunteer blood donors the mean number of circulating cells with MBR/JH vs. mcr/JH rearrangements were 0.8 vs. 0.1/ µ g DNA, and exceeded the upper normal limit (defined as the mean of all volunteer samples plus two standard deviations) in 3% vs. 2%, respectively. Analysis for MBR/JH rearrangements revealed that follicular lymphoma patients vs. volunteer blood donors were positive in 76% vs. 22% (p =0.008 by Fisher's exact test); that the mean number of MBR/JH cells per µ g of DNA was 91 vs. 0.8 (p =0.0002 by Mann-Whitney test); and the number of the MBR/JH cells exceeded the upper normal limit in 32% vs. 3% of subjects (p =0.0001 by Fisher's exact test). Circulating cells with mcr/JH were not detected among any of these 25 lymphoma patients. We conclude that patients with follicular lymphoma are more frequently positive, have higher numbers of circulating cells with t(14;18), which exceed upper normal limit more frequently than in volunteer blood donors.

Advanced ultrasound examination in the management of subfertility.

The development of new ultrasound techniques such as colour power angiography (CPA) and three-dimensional ultrasound may expand the role of ultrasound in the management of the infertile couple. Measurements of follicular blood flow velocities appears to predict the development of a healthy oocyte while high ovarian stromal vascularity is associated with polycystic ovary and the risk of ovarian hyperstimulation syndrome. Three-dimensional ultrasound with CPA provides spatial evaluation of volume flow in pelvic organs which has been used to measure vascular changes in the endometrium and improve the evaluation of tubal patency.

Leptin and leptin binding activity in the preovulatory follicle of polycystic overy syndrome patients

To investigate the clinical importance of leptin's intraovarian effects, we studied the concentration of leptin and leptin binding activity in the plasma and in the follicular fluid of PCOS patients (n=20; median BMI: 27.1 kg/m2, range 19.7- 36.3) undergoing controlled ovarian stimulation with long-term GnRH agonist, recombinant FSH, and in vitro fertilization. Follicular fluid and blood samples were collected during follicle aspiration for IVF. Total leptin concentration was measured by radioimmunoassay, and specific leptin binding activity was accessed by a gel filtration column assay. Follicular fluid and plasma leptin levels were similar (median 1135 pmol/l vs. 1409 pmol/l; p=0.81). Follicular fluid to plasma leptin ratio was independently associated with cumulative FSH dose (r=0.63; p=0.006) and insulin resistance index (r=- 0.45; p=0.04). Specific leptin binding activity was higher in the plasma than in the follicular fluid [median 7.94% vs. 3.49%; p<0.001]. When multivariate analysis was used to predict FSH consumption, only follicular fluid leptin levels were significantly associated with cumulative FSH dose (r=0.46; p=0.04). We infer that at least in part by increased intrafollicular leptin levels, obesity directly affects ovarian function in PCOS, and may induce a relative resistance to gonadotropin stimulation. This intraovarian effect of leptin can be even more profound because of low leptin binding activity in the preovulatory follicle of obese patients.

Regional hemodynamic adaptation during the menstrual cycle

Objective: To determine whether regional differences exist in uterine and systemic hemodynamic responses to the menstrual cycle, whether the hormonal environment correlates with the changes, and whether uterine artery hemodynamic adaptation depends on the side of ovulation. Methods: Twenty nulliparas had transvaginal Doppler ultrasonographic assessment of the uterine and upper-extremity radial arteries at three time points in each of two menstrual cycles. Doppler indices (peak systolic velocity, end-diastolic velocity, time-averaged maximum velocity, resistance index [RI], and blood flow) were measured in the radial and uterine arteries. Women were examined in the menstrual (cycle day 2–3), follicular (cycle day 9–10), and luteal phases (cycle day LH surge plus 9–10). At each time, serum estradiol (E2) and progesterone were measured by radioimmunoassay. Statistical analyses were repeated-measures analysis of variance and the Fisher least significant difference procedure. Results: Thirty-four nonconception ovulatory cycles were evaluated. Blood flow in each uterine artery increased significantly from a mean (± standard deviation) of 22.4 ± 7.3 mL/minute in the follicular phase to 30.7 ± 13.7 mL/minute in the luteal phase, which coincided with a reduction in the RI. The changes were independent of the side of ovulation. The radial artery did not parallel these changes (follicular blood flow of 27.2 ± 13.9 mL/minute; luteal blood flow of 24.7 ± 10.5 mL/minute). We did not identify any significant correlation between these changes and serum E2 or progesterone concentrations. Conclusion: We identified differences in the hemodynamic responses of the uterine artery compared with the radial artery during the menstrual cycle. We believe the difference indicates distinct regional control of vascular response during the menstrual cycle.

Regional Hemodynamic Adaptation During the Menstrual Cycle

In Brief Objective To determine whether regional differences exist in uterine and systemic hemodynamic responses to the menstrual cycle, whether the hormonal environment correlates with the changes, and whether uterine artery hemodynamic adaptation depends on the side of ovulation. Methods Twenty nulliparas had transvaginal Doppler ultrasonographic assessment of the uterine and upper-extremity radial arteries at three time points in each of two menstrual cycles. Doppler indices (peak systolic velocity, end-diastolic velocity, time-averaged maximum velocity, resistance index [RI], and blood flow) were measured in the radial and uterine arteries. Women were examined in the menstrual (cycle day 2–3), follicular (cycle day 9–10), and luteal phases (cycle day LH surge plus 9–10). At each time, serum estradiol (E2) and progesterone were measured by radioimmunoassay. Statistical analyses were repeated-measures analysis of variance and the Fisher least significant difference procedure. Results Thirty-four nonconception ovulatory cycles were evaluated. Blood flow in each uterine artery increased significantly from a mean (± standard deviation) of 22.4 ± 7.3 mL/minute in the follicular phase to 30.7 ± 13.7 mL/minute in the luteal phase, which coincided with a reduction in the RI. The changes were independent of the side of ovulation. The radial artery did not parallel these changes (follicular blood flow of 27.2 ± 13.9 mL/minute; luteal blood flow of 24.7 ± 10.5 mL/minute). We did not identify any significant correlation between these changes and serum E2 or progesterone concentrations. Conclusion We identified differences in the hemodynamic responses of the uterine artery compared with the radial artery during the menstrual cycle. We believe the difference indicates distinct regional control of vascular response during the menstrual cycle. Uterine perfusion undergoes hemodynamic adaptations during the menstrual cycle that are unique compared with the systemic circulation.

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

Peak systolic velocity (PSV) of individual follicles has been correlated with oocyte recovery, fertilization rate and embryo quality [in women undergoing in-vitro fertilization (IVF) and embryo transfer]. The present study assessed the role of quantitative and qualitative indices of follicular vascularity in predicting pregnancy after IVF and embryo transfer. A total of 106 women undergoing IVF treatment for infertility who were considered to be at risk of failure (>37 years of age, history of low response to gonadotrophin stimulation, or multiple failed IVF cycles) constituted the study group. PSV was measured from the three largest follicles on both the right and left ovaries on the day of human chorionic gonadotrophin (HCG) administration using an Acuson Sequoia with a 4-8 MHz transvaginal probe. The quality of follicular flow was graded from 1 to 4 according to the amount of visible colour flow around the follicle (grade 1 when one-quarter of the follicle, grade 2 when one-half, grade 3 when three-quarters, and grade 4 when the entire follicle was surrounded by colour). Clinical pregnancies resulted in 11 (10%) of the 106 high-risk women. Women who had PSV >/= 10 cm/s in at least one follicle on the day of HCG administration more often became pregnant than those with PSV <10 cm/s (P = 0.05). All pregnancies occurred in women with grade 3 or 4 follicular blood flow. Qualitative as well as quantitative measurements of follicular flow predict pregnancy after IVF and embryo transfer.

R-094. Effect of HCG administration on follicular blood flow and outcome of IVF

R-094. Effect of HCG administration on follicular blood flow and outcome of IVF

Superovulatory response in relation to time of sponge insertion

The aim of this study was to examine the association between antral follicular blood flow velocity and the response of ewes to hormonal ovarian superstimulation. Ten Santa Inês ewes were subjected to a short- (7 days; Group 1) or long-term (13 days; Group 2) progesterone (CIDR®; InterAg, Hamilton, New Zealand) priming, and a superovulatory treatment with porcine follicle-stimulating hormone (pFSH; Folltropin®-V; Bioniche Animal Health, Belleville, ON, Canada), given twice daily for four consecutive days in decreasing doses and initiated four or ten days after CIDR insertion, respectively. Embryos were recovered surgically seven days after the last pFSH dose. From one day prior to until the end of the pFSH regimen (Days −1 to 3), all ewes underwent daily transrectal ultrasonography of ovaries. The number of high-velocity pixels (HVPs; 0.055–0.11 m/s or upper 50% of recordable velocities) on Day 1 correlated directly with the number of corpora lutea (CL; r = 0.92, P = 0.0002) and of viable embryos (r = 0.77, P = 0.01). Correlations were also recorded between the number of HVPs on Day 3 and the recovery rate (r = −0.69, P = 0.03), viability rate (r = −0.64, P = 0.05), and percentage of degenerated embryos (r = 0.65, P = 0.04). The percentage of HVPs relative to the total area of ovarian cross section on Day 1 was correlated with the number of CL (r = 0.95, P < 0.001) and of viable embryos (r = 0.85, P = 0.002). This parameter on Day 3 was also correlated with the recovery rate (r = −0.69, P = 0.03). The percentage of HVPs relative to the total Doppler area on Day 0 was correlated with the recovery rate (r = 0.72, P = 0.02). It can be concluded that sonographic assessment of high-velocity antral follicular blood flow has the makings of a useful non-invasive method to predict the outcome of the superovulatory treatment in ewes.

Clinical observation on effect of yangjing decoction in promoting follicular growth

To investigate the effect of Yangjing Decoction (YJD, a Chinese prescription of replenishing Kidney essence) in promoting follicular growth and its influence on blood supply of ovary and uterus. Twenty-two cases with secondary amenorrhea and 4 cases of infertility with infrequent menstruation caused by follicle maldevelopment were treated with YJD. The blood supply of ovary and uterus in 7 cases was measured by colour Doppler before and after treatment. Of the 116 therapeutic cycles in 26 cases, there were 69 menstrual cycles (59.48%), 37 follicular maturation cycles (31.90%), 21 ovulation cycles (18.10%), and the follicular maturation rate was 84.62%, The disturbance in blood supply of ovary and uterus was improved remarkably along with follicular development by YJD in 7 cases. YJD could improve follicular development and blood supply of ovary and uterus.

Ultrasound derived indices of follicular blood flow before HCG administration and the prediction of oocyte recovery and preimplantation embryo quality.

The principal aim of the study was to relate ultrasound-derived indices of blood flow in individual follicles on the day of, but before, the administration of human chorionic gonadotrophin (HCG) to the subsequent recovery of oocytes and the production of preimplantation embryos. Data were obtained from 21 women (aged 29-43 years) with bilateral tubal occlusion, who were undergoing treatment by in-vitro fertilization (IVF) and embryo transfer. Transvaginal ultrasonography with colour Doppler imaging and pulsed Doppler spectral analysis were used to measure follicular volume and derive indices of blood flow. The end-points for each follicle were the volume, peak systolic velocity (PSV), pulsatility index (PI), and the recovery or non-recovery of an oocyte, the subsequent production or non-production of a preimplantation embryo and the morphological grade of each embryo. A total of 94 follicles were studied; 74 oocytes were recovered (79%) and 40 embryos (33 grade I or II) were produced. There were four clinical pregnancies (pregnancy rate 25.0% per transfer, 19.0% per patient). There was a significant correlation between whether or not follicular blood flow was detected and whether or not an oocyte was recovered (P < 0.05, chi 2 test). The values for volume and PI were not clinically useful. The PSV (cm/s, mean +/- SD) was higher in follicles that were associated with the production of an embryo (12.7 +/- 5.9) compared with those that were not (8.5 +/- 5.0; P < 0.05, Student's t-test). The probability of producing a grade I or grade II embryo was 75% if the PSV was > or = 10 cm/s. The corresponding value was 40% if the PSV was < 10 cm/s and 24% if blood flow was not detected (i.e. PSV < 3 cm/s). There was a significant increase (P < 0.05, Student's t-test) in the PSV before aspiration in those follicles associated with the subsequent production of an embryo. We conclude that the value for PSV, before the administration of HCG, can be used to identify follicles with a high probability of producing an oocyte and a high grade preimplantation embryo. The information may also be used to time the administration of HCG to achieve the optimum number and quality of embryos for patient management.