Fig 6 - uploaded by Roger A Pierson
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Ultrasonographic images of a preovulatory follicle taken at approximately 15 minute intervals during the 3 hours and 17 minutes preceding ovulation. The fIna/ Image in the series (lower right) represents the onset of ovulation. Timecode values displaying hours, minutes, seconds and video frame are shown in the lower left portion of each image. Subtle changes in the echotexture of the follicle wall are noted as the interval to ovulation decreases. Dramatic changes in the shape of the follicles and pronounced thinning of the wall at the stigma are observed prior to the onset of ovulation.
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Our objectives were to characterize ultrasonographically detectable changes in the human preovulatory follicle wall and to determine whether predictors of impending ovulation could be identified. Volunteers were given human chorionic gonadotropin (hCG) to induce ovulation when the preovulatory follicle first attained 18 to 20 mm. Beginning 34 h aft...
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Citations
... Also, details of the ultrasound performed in our clinic at the time of the study have been reported previously. 24,[30][31][32] In addition, semen analysis techniques were nonstandardized at the time that this study was conducted. However, the high doses of r-hFSH administered and the liberal criteria for ovulation triggering limit detailed comparisons of our data with more recent work. ...
Objective:
To evaluate recombinant human luteinizing hormone (r-hLH) versus urine-derived human chorionic gonadotropin (u-hCG) to trigger ovulation in women (aged 20-40 years) with WHO Group II anovulatory infertility undergoing ovulation induction (OI) with recombinant human follicle-stimulating hormone (r-hFSH) (150 IU/day starting dose).
Study design:
For this Phase II, open-label, dose-finding pilot study, patients were randomized to doses of 825, 2,750, 5,500, 11,000, or 22,000 IU r-hLH or u-hCG (5,000 IU). Primary endpoints were ovulation and ratio of ruptured follicles/follicle > or = 15 mm (day of r-hLH/ u-hCG administration). Secondary endpoints included monofollicular ovulation and clinical pregnancy rates.
Results:
All 67 randomized patients completed treatment. All patients in the r-hLH 2,750 (13/13), 5,500 (12/ 12), 11,000 IU (13/13), and u-hCG 5,000 IU (12/ 12) groups ovulated; 3/5 patients in the r-hLH 825 IU and 2/12 in the r-hLH 22,000 IU group failed to ovulate (p = 0.105 between evaluable groups). The mean ratio of ruptured follicles/ follicle > or = 15 mm was 1.1 (p = 0.675 between groups). The monofollicular ovulation rate was 15/60 (25%). Two cases of ovarian hyperstimulation syndrome were reported.
Conclusion:
This open-label, pilot study (conducted in 1999-2001) suggests that the minimal effective dose of r-hLH to trigger ovulation in women with WHO Group II anovulatory infertility undergoing OI with r-hFSH (150 IU starting dose) was 2,750 IU.
... Ovulation was defined as the disappearance of a follicle greater than 15 mm in diameter identified the previous day and confirmed with visualization of a corpus luteum [11,12,23,24]. Ovulation was used as a reference point (Day 0) to standardize the data for natural cycle follicles. ...
The purpose of this study was to characterize ovarian follicular and endometrial development during conventional vs. continuous oral contraceptive (OC) dosing regimens, to explore follicular development during the hormone-free interval (HFI) and to examine follicular development following OC discontinuation.
A randomized clinical trial involving 36 clinically normal healthy women between the ages of 18 and 35 years (24.4 +/- 3.9, SEM). Transvaginal ultrasonography and blood sampling were done to ascertain ovarian function.
Fewer follicles > 4 mm developed during continuous vs. conventional OC use (p = .006). No dominant follicles developed during continuous OC use vs. eight dominant follicles (16.1 +/- 3.3 mm) during the conventional OC regimen. Two of eight (25%) dominant follicles ovulated. All dominant follicles began development during the HFI. Following discontinuation of OC use, ovulation took approximately 5 days longer when compared to natural cycles.
Continuous OC regimens more effectively prevent dominant follicle development and breakthrough ovulation. The slight delay in time to ovulation following OC discontinuation and natural cycles could be attributed to suppression of follicle wave activity.
... Ovulation was defined as the disappearance of a follicle greater than 15 mm in diameter identified the previous day and confirmed with visualization of a corpus luteum[11,12,23,24]. Ovulation was used as a reference point (Day 0) to standardize the data for natural cycle follicles. ...
Computer-assisted analyses were used to examine ultrasound image attributes of human dominant ovarian follicles that developed during natural and oral contraceptive (OC) cycles. We hypothesized that image attributes of natural cycle follicles would quantitatively differ from those in OC cycles and that OC cycle follicles would possess image attributes indicative of atresia.
Dominant ovarian follicles of 18 clinically normal women were compared using transvaginal ultrasonography for the 7 days before ovulation during a natural cycle (n = 9) or the 7 days before peak estradiol in women using OC (n = 11). Follicles were analyzed using region and line techniques designed to compare the image attributes numerical pixel value (NPV), pixel heterogeneity (PH) and area under the curve (AUC).
NPV was higher in OC cycle follicles with region analysis and tended to be higher with line analysis (p = 0.005 and p = 0.06, respectively). No differences were observed in two other image attributes (AUC and PH), measured with either technique, between natural and OC cycle follicles.
The increased NPV value of OC cycle follicles and lack of differences in PH and AUC values between natural cycle and OC cycle follicles did not support the hypothesis that OC cycle follicles would show ultrasonographically detectable signs of atresia. Image attributes observed in OC cycle follicles were not clearly indicative of atresia nor were they large enough to preclude preovulatory physiologic status in OC cycle follicles.
Study objective: To study the relationship of ultrasonographic changes in the walls of the dominant follicle with the outcomes of its growth – ovulation or persistence.
Study design: Prospective cross-sectional study.
Patients, Methods, Settings: Upon results of sonographic one cycle pre-assessment, 96 women from subfertile couples were distributed into two groups. Main group – 78 women with documented ovulation. Comparison group consisted of eighteen women with various clinical forms of follicle persistence. Ovulation stigma identification was performed by transvaginal ultrasonography using the technique of Mobile Hydroacoustic Window (TVS+MHAW) with standard 6–10 MHz probes. Three sources of fluid were used for the building of mobile hydroacoustic window: antral fluid, contents of ovulation stigma and the fluid located close to ovary apex. Subtle structures of follicle walls were assessed at the interface of liquid and dense medium in the area of ovary apex.
Results, Discussion: In 52 cases (66.6%) two main types of ovulation stigma – Bleb-type and Flat-type were identified, in 48 (61.5%) and 4 (5.1%) cases, accordingly.
In the rest of 26 (33.3%) ovulating women it was not possible to identify the stigma sonographically. In 18 (18.8%) cases anovulatory cycles were presented: LUF in 10 (10.4%) cases, follicular regression in 6 (6.3%) and haemorrhagic cysts developed in two cases (2.1%). Local thinning of follicular walls in the area of stigma (91%), appearance of small amount of fluid near the ovary apex (93.6%) and elongated or cone-like shape of the pre-ovulatory follicle (59%) were the most prevalent sonographic signs of stigma formation. Stages of sonographic changes of the structure of forming ovulation stigma were detected and described. New sonographic sign of ovulation stigma, – the phenomenon of Constriction Ring (30.8%), characterizing the closing stage of stigma formation was described. Mean growth and regression rates were calculated for dominant follicles. The increase of dominant follicle size beyond 28.5 mm is connected to high risk of its anovulation or persistence. It should also be taken into account that ovulation can occur at any stage of stigma formation, also without its sonographic appearance.
Conclusion: The study of phenotypic features of stigma formation by means of TVS + MHAW can be useful for timing of OPU in IVF natural cycles and prediction of high risk of follicle persistence/regression at intrauterine insemination.
To compare growth rates of ovarian follicles during natural menstrual cycles, oral contraception (OC) cycles, and ovarian stimulation cycles using standardized techniques.
Prospective, comparative, observational, longitudinal study.
Healthy volunteers in research trials and infertility patients undergoing treatment at an academic institution.
Women were evaluated during natural cycles (n = 50), OC cycles (n = 71), and ovarian stimulation cycles (n = 131).
Serial transvaginal ultrasonography was performed to measure follicle diameter. Day-to-day growth and regression profiles of individual follicles were determined. Mean growth rates were calculated for ovulatory follicles. Mean growth and regression rates were calculated for anovulatory follicles.
Follicle growth rate (in millimeters per day).
Mean follicular growth rate was greater during ovarian stimulation cycles (1.69 +/- 0.03 mm/day) compared to natural (1.42 +/- 0.05 mm/day) and OC cycles (1.36 +/- 0.08 mm/day). The interval from dominant follicle selection to ovulation was shorter during stimulation cycles (5.08 +/- 0.07 days) compared to natural cycles (7.16 +/- 0.23 days).
Follicles grew faster during ovarian stimulation therapy compared to natural cycles or OC cycles. Greater follicular growth rates in stimulation cycles were associated with shorter intervals from selection to ovulation. The biologic effects of increased follicular growth rates and shorter intervals to ovulation on oocyte competence in women undergoing assisted reproduction remain to be determined.
