Ovulation Index Research Articles

Effect of the different phases of the menstrual cycle and oral contraceptives on athletic performance.

The female athlete, during her reproductive years, has a complex and ever-changing milieu of female steroid hormones, whether it is the endogenous variations in estradiol and progesterone of a regular menstrual cycle, or the exogenous synthetic hormones of the oral contraceptives. Both estrogens and progestins have individual, interactive and sometimes opposing physiological actions with potential implications for the exercising female. In retrospective surveys on the menstrual cycle and performance, from 37 to 63% of athletes did not report any cycle 'phase' detriment, while 13 to 29% reported an improvement during menstruation. The best performances were generally in the immediate postmenstrual days, with the worse performances during the premenstrual interval and the first few days of menstrual flow. However, this type of study has an inherent built-in bias, and is further limited by the lack of substantiation of cycle phase. Many of the women studied associated premenstrual symptoms, such as fluid retention, weight gain, mood changes, and dysmenorrhoea with performance decrement. Such factors have also been causally linked with an increase in traumatic musculoskeletal injuries during the premenstrual and menstrual period. Neuromuscular coordination, manual dexterity, judgement and reaction time for complex tests have been shown to be adversely affected in women with premenstrual syndrome or symptoms, but confounding variables may include nutrition status and blood sugar levels. In addition, not all women suffer to the same level with premenstrual symptoms. Fluctuations in many physiological functions occur throughout the normal menstrual cycle. Results of early studies are difficult to interpret owing to the small numbers of women studied, wide range of fitness levels, and variability in the definitions of cycle phase. Nevertheless, investigators did not document any significant changes in measures of athletic performance as a function of timing of testing during the menstrual cycle. Swimmers have shown a premenstrual worsening of performance times, with improvement during the menstrual phase and on the eighth day of the cycle. An increase in perceived exertion was noted premenstrually and during the early menstrual stage with very intense exercise. In cross-country skiers, the best times were recorded in the postovulatory and postmenstrual phases, prompting the recommendation that training loads be selected according to cycle phase to achieve maximum benefit. Investigations using estradiol and progesterone levels as a confirmatory index of ovulation have not generally found significant differences across the cycle in either maximal or submaximal exercise responses, although a slight decrease in aerobic capacity during the luteal phase has been reported.(ABSTRACT TRUNCATED AT 400 WORDS)

The reliability, acceptability and applications of basal body temperature (BBT) records in the diagnosis and treatment of infertility

The possibilities and limitations of basal body temperature (BBT) records as an adjunct in the management of infertility were re-evaluated. To assess its accuracy as an index of ovulation, 172 charts were analyzed by three different physicians. While the average true positive rate was 90%, the false negative rate was only 2%. The remaining graphs (8%) were classified as non-interpretable, probably reflecting measurement problems. Retrospective assessment of 210 biphasic records showed the thermal nadir to occur within 1 day of the urinary luteinizing hormone (LH) surge in 75% of the cases, and in 90% when 2 days where considered. This confirms BBT as a relatively accurate guide for retrospective identification of the periovulatory period. Moreover, results of a study conducted to investigate how patients experienced daily recording of BBT graphs suggest that the method is well accepted by a high proportion of women. From all these it appears that there are many indications where BBT graphs can still be applied. Development of new electronic devices may further improve the reliability, acceptability and applications of the BBT records in the fertility investigation.

Effect of FSH deprivation at specific times on follicular maturation in the bonnet monkey (Macaca radiata)

Cyclic monkeys were deprived of FSH for specific periods on different days of the follicular phase by injecting them with minimal doses of an FSH antiserum characterized for specificity and bioneutralizing ability. The effect of the antiserum on follicular maturation was assessed by determining (a) serum oestrogen concentrations through the midcycle period, (b) serum progesterone concentrations as an index of ovulation and luteal function, (c) laparoscopic examination of the surface of the ovary when necessary, and (d) overall cycle length. While antiserum injection on Day 5 of the cycle caused delay in the oestrogen surge from Days 9 to 11, injection on Day 6 led to the occurrence of two oestrogen surges, on Days 9 and 14. Laparoscopic examination showed that the earlier follicle had disappeared and a new follicle had appeared by Day 14. Antiserum injection on Day 7 of the cycle arrested further growth of the maturing follicle, but a new follicle appeared 9 days later, as indicated by a surge of oestrogen on Day 16. Injection of antiserum beyond Day 7 had no effect on follicular development, ovulation and luteal function. These observations suggest that the mature follicle becomes relatively independent of FSH support about 48 h before ovulation and this event could be a marker for follicular dominance.

Sexual maturation of ewes raised without ram exposure in a controlled lighting environment

Finn × Dorset ewe lambs (n = 70) born in the spring (March 28 to April 6) from two successive lambing seasons were evaluated for age at first ovulation in the absence of mature rams. Ewe lambs were born in a controlled, short light (8L:16D) photoperiod or in ambient light (13L:11D). At about 10 to 11 wk of age, ewe lambs were allocated to a short (8L:16D) or long (16L:8D) light environment. Plasma progesterone (P 4) concentrations were measured as an index of first ovulation. First exposure of ewes to sexually mature rams was in November. Most ewe lambs (77%) ovulated before ram exposure. More lambs (P < 0.025) born in ambient light and raised in short light reached puberty with typical cycles of plasma progesterone compared to other treatments. Long days tended to retard the onset of puberty. Although pregnancy rate did not differ across light treatments, more ewes became pregnant from the ambient-light born and short-light raised treatment. Photoperiod is an important factor affecting the onset of sexual maturation and genesis of normal luteal progesterone secretion in the ewe lamb.

Effects of hormonal treatments on induced ovulation in gudgeon, Gobio gobio L.

The effectiveness was studied of different hormonal treatments to induce gamete emission in a wild stock of a European baitfish, the gudgeon ( Gobio gobio L.). Ovulation was induced by injection of a hypothalamic factor, the luteinizing hormone-releasing hormone superactive analog (D-Trp 6, des Gly 10-LHRH), in combination with pimozide (PIM), a dopamine antagonist, or by injection of a carp pituitary extract (CPE). More than 60% of treated females ovulated after injection of CPE (10.0 μg/g) and nearly 100% after injection of PIM+LHRH-A. There was a large variability in the time between injection and stripping and in fertilization success. Hatching rate varied between 0 and 95% and there was no relationship with latency time or ovulation index. Different techniques are proposed to resolve these problems.

Changes in episodic luteinizing hormone secretion leading to puberty in the lamb.

In this study, we monitored episodic luteinizing hormone (LH) secretion throughout development in eight April-born ewe lambs to determine if a change in LH pulse patterns preceded first ovulation at puberty. LH pulses were measured in samples collected every 12 min for 6 h once in July, twice a month from 22 August to 2 October, and then weekly until puberty. Progesterone concentrations, measured in samples taken 3/wk, were used as an index of first ovulation, which occurred at 29.3 +/- 0.7 wk of age. LH pulse frequencies throughout most of this period ranged from 0 to 2 pulses/6 h, with no change over time. However, during the week prior to the first progesterone rise, there was a significant increase in pulse frequency to a level seen during the follicular phase in post-pubertal lambs. This increase in pulse frequency was evident in 7 of 8 lambs; pulses were not analyzed in the last lamb because samples were taken during the LH surge. In contrast, LH pulse amplitude did not increase prior to puberty. In fact, pulse amplitude declined linearly during the 3 wk before first ovulation and then increased during the follicular phase in post-pubertal animals. These results support the hypothesis that an increase in the frequency of episodic LH secretion is a key event leading to the onset of ovarian cycles in the lamb. Whether an increase in pulse amplitude is also necessary remains unclear. If so, it must occur just before the LH surge, since it was not detected in any samples taken before puberty in this study.

Relationships between ovarian morphology, vaginal cytology, serum progesterone, and urinary immunoreactive pregnanediol during the menstrual cycle of the cynomolgus monkey.

Three different indices of ovulation and luteal activity were studied in eight regularly cycling cynomolgus monkeys. A significant relation between changes in serum progesterone and immunoreactive pregnanediol (I-PD) in urine was obtained. The occurrence of ovulation could be determined reliably from a change in the ratio of cornified to basal epithelial cells in vaginal smears, and luteal activity could be assessed reliably from daily measurements of urinary pregnanediol. The time of ovulation could be defined more precisely by daily I-PD radioimmunoassays than by the vaginal smear pattern. Measurements of I-PD also have the advantage of ease and noninvasiveness over serum progesterone determinations. More detailed information about changes in hormonal activities could not be obtained reproducibly from thorough examination of cell types in vaginal smears.

The influence of continuous intrauterine infusion of enzyme-inhibitors of the arachidonic acid cascade on ovulation and tubal ovum transport in the hyperstimulated rabbit.

Cyclo-oxygenase and prostaglandin-15-hydroxydehydrogenase are rate-limiting steps in the arachidonic acid cascade. These enzymes were affected by indomethacin and lonazolac treatment in hyperstimulated rabbits through continuous intrauterine or single vaginal applications in three different experiments. In terms of the ovulation-index, there was no difference between animals treated via the intrauterine or the vaginal routes. Compared with controls (83 to 89%), there was a significant reduction in the ovulation index to 32% with indomethacin and to 51 or 55% with lonazolac, 28 h after induction of ovulation (experiment 1). The values turned almost back to normal 52 h after induction of ovulation 72% (experiment 3). The treatment with lonazolac resulted in a higher sum of corpora lutea and unruptured follicles (experiment 1: control-group = 90.9 vs lonazolac-group = 110.5). The recovered ova showed a shift from the 4 and 8 cell stages to the 16 or more cell stages under lonazolac treatment when compared with controls (experiment 3). The histologic examinations showed advanced luteinization of unruptured follicles in the indomethacin-treated groups. Hyperplasia of the theca interna was also noted. Our data indicate that indomethacin was capable of inducing premature luteinization resulting in arrested or delayed ovulation. Lonazolac, in contrast, did not impair ovulation. Moreover, it induced the growth of more follicles, probably through a second wave at the time of ovulation initiated by hCG. For the clinical practice these experiments point towards the possibility of the treatment of the luteinized unruptured follicle syndrome and towards the application of lonazolac for ovarian stimulation.

Effect of boar presence before and after weaning on estrus and ovulation in sows.

Two hundred sixty-two sows were used to investigate the effects of boar exposure during the last week of nursing (BPRE) and after weaning (BPOST) on the return to estrus. Because approximately one-half of the sows were weaning their first litter, a third factor, primiparous vs multiparous (LITT), was considered in the statistical analysis. To evaluate the effect of treatment on ovarian activity, the sows were also blood-sampled twice weekly for 3 wk after weaning for the measurement of plasma progesterone concentrations as an index of ovulation. Boar exposure after weaning was the most important stimulus of early ovulation and estrus after weaning (P less than .001). A greater proportion of first-litter sows exhibited estrus later (P less than .02) and ovulated later (P less than .09) than did multiparous sows. First-litter sows were unaffected (P greater than .10) by boar exposure before weaning. Multiparous sows were sensitive to boar exposure during nursing. Maximal boar exposure for these sows (BPRE + BPOST) resulted in 95% of sows in estrus and ovulating within 20 d of weaning. No boar exposure resulted in 45% and 38% anestrus and anovulatory sows. Boar exposure, either before or after weaning, was effective in reducing the number of anestrus and anovulatory sows to between 15 to 30%. The effects of BPRE and BPOST on return to ovulation were additive and approximately equal.

Correlation between ultrasonic, laparoscopic, histological and biochemical indices of ovulation

SummaryUltrasonic, laparoscopic, histological and biochemical indices of ovulation were correlated in 20 spontaneous ovulatory cycles. The results show that in 75 per cent of the cycles, all parameters were perfectly correlated. In 25 per cent of instances luteinised unruptured follicles and poor luteal phase endometrium were encountered. These findings may partly explain the relative infertility of the human race and many cases of apparently unexplained infertility. The implications of these findings on the prediction and detection of ovulation are discussed.

Hormonal indices of ovulation and the fertile period.

Pregnancy rarely occurs in women under the age of 14 years or over the age of 50, and for the majority the most fertile time of life lies between the ages of 20 and 35 years [1]. During this period the ovaries are fully functional, and alternately undergo a series of cyclical changes that culminate in the release of an oocyte into one of the oviducts every 25-33 days [2]. The average healthy woman will have approximately 400 menstrual cycles and ovulation may occur at any time between days 12-25, but most frequently around day 16 [3]. Accordingly, the time when coitus may lead to pregnancy is a periodic phenomenon and can be described only in statistical terms due to uncertainty about the occurrence and exact time of ovulation, the variable lifespans of the gametes and their ability to meet in the female reproductive tract. Nevertheless, a variety of methods have been developed to identify the outer limits of the fertile period during each menstrual cycle, and a couple may use this information to help avoid or achieve a pregnancy by having sexual intercourse at the appropriate times [4]. More recently, tests have been devised which signal the time of maximum conception probability to aid the management of subfertile patients who wish to conceive [5,6].

An estrogen test to determine the times of potential fertility in women

Defined changes in the concentration of estrone glucuronide in daily samples of early morning urine have been used to locate the limits of the fertile period and the time of maximum conception probability during 118 cycles (106 menstrual, 12 conceptional) in 73 women. The peak day of urinary luteinizing hormone was used as an index of ovulation. Follicular growth was monitored daily by ultrasonography throughout 38 cycles, and the time of maximum follicular diameter was used as an alternative reference point to define the times of potential fertility according to the life spans of the gametes. With optimized algorithms and the best index of ovulation, the estrogen test delineated the limits of the fertile period in 89% of the tests (mean length, 10.8 days; range, 5 to 17 days) and the time of maximum conception probability in 82% of the cycles, with a mean time to the maximum follicular diameter of 0.42 days (range, -4 to +4 days).

Coital stimuli controlling luteinizing hormone secretion and ovulation in the female ferret.

A series of experiments focused on the masculine coital behaviors controlling pituitary luteinizing hormone (LH) secretion and reflex ovulation in the estrous female ferret. An initial experiment investigated which coital stimuli from the male are required to induce ovulation. It was found that corpus luteum formation, which served as an index of ovulation, occurred in estrous female ferrets only if the male achieved a penile intromission. Neck gripping, mounting, and pelvic thrusting behavior without intromission by the male failed to induce ovulation. A second experiment investigated the timing and magnitude of the coitus-induced LH surge associated with ovulation. Blood was obtained via jugular catheters from estrous females in various mating situations. Plasma LH concentrations were measured by a heterologous radioimmunoassay that was validated for use in the ferret. A significant surge in plasma LH occurred only when an intromission was achieved by the stud male. Plasma LH was significantly elevated 2.0 h after the introduction of the male, peak values were reached 6.0 h later, and this elevation lasted on average 5.7 hours (5/5 females). No LH rise occurred in 2/2 female ferrets in which only neck gripping, mounting, and pelvic thrusting, but no intromission, were allowed to occur. The ferret mating pattern and the resultant LH response differ from those seen in three other induced ovulators (cat, vole, and rabbit) in which the male's intromission latency and duration are much shorter than in the ferret, and in which a distinctive peak in plasma LH often occurs within 1 h after mating.

Sequential hormone measurements after first trimester abortion in normal Nigerian women.

This study looks at the dynamics of the pituitary hormones and progesterone in normal adult Nigerian females during their first postabortal cycle. Serial determinations of serum concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PrL) and progesterone were carried out on eleven normal Nigerian women during the first postabortal period after menstrual regulation. Nine out of the eleven subjects (82%) attained LH peaks within the first 22 days after menstrual regulation, seven had discernible FSH peaks and seven had serum progesterone concentrations greater than 6 nmol/l during the second half of the study period. Subjects probably ovulated during the first postabortal cycle; serial LH seems to be the most reliable index of ovulation in our subjects. We hope these data will aid in development of effective family planning strategies for women in the first postabortal cycle.

Progesterone and estradiol in the saliva and plasma during the menstrual cycle

Plasma and salivary progesterone and estradiol were measured throughout nine menstrual cycles and before and after intramuscular injection of progesterone in four women. Mean ± standard error of the mean (SE) salivary progesterone increased significantly from 238.7 ± 14.3 pg/ml in the proliferative phase to 475.3 ± 39.8 pg/ml in the secretory phase (p < 0.001). There was a highly significant correlation between plasma and salivary progesterone levels throughout the menstrual cycle (r = 0.5841, p = 0.001). The ratio of plasma to salivary progesterone was 6.4 during the proliferative phase and increased to 26.7 during the secretory phase. Free unbound progesterone as determined by equilibrium dialysis gave a mean ± SE level of 126.8 ± 6.9 pg/ml during the proliferative phase and increased significantly to 196.8 ± 18.8 pg/ml during the secretory phase (p < 0.001). The corresponding levels in the plasma were 88.5 ± 11.2 pg/ml, which increased significantly to 332.2 ± 39.2 pg/ml (p < 0.001). Free progesterone constituted 53.7% and 41.4% of salivary progesterone during the proliferative and secretory phases, respectively, whereas the corresponding percentages in the plasma were 5.8% and 2.6%. Both plasma and salivary progesterone levels increased in a dose-dependent manner after an intramuscular injection of progesterone, with peak levels being attained from 2 to 3 hours after the injection. Salivary estradiol levels were 5 to 18 and 8 to 35 pg/ml in the proliferative and secretory phases, respectively, but showed no correlation with plasma estradiol levels. The findings are discussed in relationship to the origin of salivary progesterone and the potential use of it as an index of ovulation.

Plasma progesterone levels as an index of ovulation

Plasma progesterone levels were measured in three groups of untreated women. (1) Nine women with follicle rupture, proved by laparotomy or laparoscopy, had values of greater than or equal to 40 nmol/l on days 18-24 (days-10- -5 from the next period); thus a value of less than 40 nmol/l should not be taken as evidence of ovulation. (2) Nineteen healthy women with normal menstrual histories had hormone assays on alternate days during one cycle. In five of them all values were less than 38 nmol/l. (3) Forty women had a single progesterone assay on days 20-29 of a conceptual cycle. Eight of them had a level less than 40 nmol/l. Ovulation had certainly occurred in all of them, but it is difficult to assess whether the sample timing was optimal since there was no following menstrual period. Progesterone levels in drug-induced conceptual cycles were in general higher than those in spontaneous pregnancy cycles. Women with luteinization of the unruptured follicle frequently had values of greater than 40 nmol/l. Conversely, a secretory endometrium was not uncommon in cycles with values of less than 38 nmol/l.

Effect of estradiol-treated females on all-female groups of rhesus monkeys during the transition between the nonbreeding and breeding seasons.

Behavior, sex steroid levels and sex skin color were monitored in 2 out-door-housed all-female groups of rhesus monkeys during the nonbreeding season and into the breeding period. Each group contained gonadally intact and ovariectomized (OVX) females. In one group, 2 OVX females were implanted with estradiol benzoate pellets. Female-to-female sexual behavior, sex skin redness and endocrine indices of ovulation (in intact females) all increased as the breeding season approached. The two groups did not differ with regard to these measures. This lack of difference suggests that the presence of males may be required to mediate socially facilitated out-of-season breeding by females. No strong relationships were detected between steroid levels of intact females and sex skin color or female-to-female sexual behavior in all-female groups.

The relationship of the corpus luteum and the endometrium in infertile patients

A group of 50 females undergoing an infertility work-up had measurements of serum progesterone levels in all cases, endometrial sampling in 49, and biopsy of a grossly identifiable corpus luteum in 42 cases. Of the 41 cases with three parameters available for study, 39 had correlations of all three parameters. The remaining nine cases had two of three parameters available for study. Of these, three showed a secretory endometrium but absent corpus luteum and an anovulatory progesterone level, and a patient showing a proliferative-phase endometrium at the same time had an ovulatory progesterone level and a postovulatory corpus luteum. The evidence presented suggests that, among the three parameters tested, the progesterone level as a noninvasive procedure serves as a good index of ovulation 92% of the time, and occasionally endometrial histologic sampling does not necessarily reflect ovarian function.

A study of peroxidase levels in human cervical mucus as an index of ovulation.

Fourteen healthy women were screened for the following parameters throughout one complete menstrual cycle: levels of urinary oestrogens and pregnanediol; levels of plasma and urinary gonadotrophins; and pH, protein content and levels of peroxidase in the cervical mucus. It was found that concentrations of peroxidase in the cervical mucus were not a reliable index of ovulation.

A study of the use of intermittent serum luteinizing hormone, progesterone and oestradiol measurements for the detection of ovulation.

The value of luteinizing hormone (LH), progesterone (P) and oestradiol (E2) in serum as an index of ovulation and corpus luteum function was studied in blood samples collected at infrequent intervals during the menstrual cycle from 19 healthy Thai women. A serum P level of more than 3 ng/ml was detectable in 70 to 80 per cent samples obtained between days 20 and 25 and a P peak and/or E2 peak (greater than 150 pg/ml) were found at this time in 85 to 94 per cent of the cycles. In not more than 26 per cent of the cycles was an LH peak (greater than 150 ng/ml-LER-907) detected when all results were considered. A significant P and/or E2 peak on day 22 or 23 occurred in more than 78 per cent of 25 to 33 day cycles, whereas, the P and/or E2 peak was detectable in only 50 per cent of the cycles lasting less than 25 or more than 33 days. The postovulatory serum P levels were the ones most consistently raised in patients studied over several consecutive cycles.