Basal body temperature as a method of ovulation detection: comparison with ultrasonographical findings

Basal body temperature assessment: is it useful to couples seeking pregnancy?

Advanced practice nurses in primary care settings are often asked to give appropriate advice to couples seeking pregnancy. This article examines the issue of basal body temperature (BBT), a time-honored way to establish the presence of ovulatory cycles, and asks if BBT is an outdated recommendation. The article also reviews the benefits and limitations of recommending BBT to couples seeking pregnancy in light of recent fecundity research.

Sex steroid metabolism and menstrual irregularities in the exercising female. A review

This article aims to clarify why, and by which mechanisms, exercise may influence the normal menstrual cycle. Therefore, the vast amount of literature on this subject is reviewed and a critical appraisal of the most widespread hypotheses if offered. The strikingly low body mass which frequently accompanies exercise-related menstrual irregularities (ERMI) has led some authors to develop a hypothesis which postulates that a critical percentage of body fat is essential to trigger normal menstruation. The relevance of any reference to anorexia nervosa to support this view lacks consistency: female athletes differ in many ways from patients with anorexia nervosa, not least in their excellent physical status which is essential to deliver first-class performances. ERMI is not identical to the so-called female athlete triad, a complicated pathology that involves ERMI, premature osteoporosis and disordered eating. ERMI itself does not seem to have any substantial pathological effects as long as attention is paid to preventing osteoporosis or stress fractures which may result from prolonged hypo-estrogenaemia. In the female athlete with ERMI who wishes to conceive, the accompanying subfertility may necessitate a response other than a prompt reduction in training intensity, as this is hardly a first choice for any top athlete. During recent years, a number of prospective studies have greatly contributed to our understanding of the complexity of the mechanisms involved in ERMI. Older hypotheses, such as those considering hyperprolactinaemia as the cornerstone of ERMI, have now been firmly rejected. The present hypotheses emphasise the importance of caloric deficiency and limited energy availability, although they still fail to identify the actual mechanism that causes ERMI. There is, however, evidence that ERMI is produced by a disturbance of the hypothalamic gonadotrophin-releasing hormone oscillator. This disturbance is caused by either an insufficient estrogen or progesterone feedback or by an imbalance of local opioid peptide and catecholamine activities mediated by gamma-aminobutyric acid (GABA), corticotrophin-releasing hormone and insulin-like growth factor-1. More recent experiments have also linked ERMI with changes in steroid metabolism, in particular, an increasing activity of catecholestrogens possibly leading to enhanced intracerebral noradrenaline (norepinephrine) levels that may interfere with normal gonadotrophin release. This article demonstrates that the outcome of the many studies of ERMI is characterised by much controversy and numerous methodological flaws. The importance and complexity of some recent findings necessitate a comprehensive study which links older and newer findings within a critical perspective.

Ultrasound evaluation of ovarian activity under oral contraceptives

The trend towards changing the composition of the contraceptive pill in order to decrease side effects might lead to increased ovarian activity. This may decrease reliability. Therefore, a non-invasive method for monitoring the suppressive effect of the pill on ovarian function is warranted. The aim of the present study was to investigate whether or not diagnostic ultrasound might be the method of choice for studying residual ovarian activity during pill use. In 89 women on a low-dose oral contraceptive (30 mcg ethinyl-estradiol (EE)/75 mcg gestodene), the first two months of pill-intake were monitored extensively with diagnostic ultrasound. The study revealed that only one ultrasound investigation was needed during the first week of pill intake to discover all relevant cases of residual ovarian activity. Follow-up investigations are needed to quantify this activity more specifically.

The monitoring of the menstrual status of female athletes by salivary steroid determination and ultrasonography

This study was designed to evaluate whether traditional plasma hormone determinations can be adequately replaced by measurements of salivary hormones. Eleven young sportswomen with menstrual irregularities attributed to strenuous physical exercise participated in this study. Mean body weight expressed as a percentage of ideal body weight was 92%, SD 4%. Their mean weekly training distance was 35 km, SD 15. Basal plasma endocrinological measurements revealed a hypo-oestrogenic status (mean plasma oestradiol values: 22 pg.ml-1, SD 8.8), and a deficient luteal phase (mean plasma progesterone: 2.9 ng.ml-1, SD 2.1). Pre-exercise salivary sex steroids were low. Salivary progesterone levels were 39.3 pg.ml-1, SD 9.5 (normal ranges in saliva: 25-60 pg.ml-1), salivary oestrone (E1) was 12.2 pg.ml-1, SD 2.3 (normal ranges in saliva: 7.5-25 pg.ml-1), and salivary oestradiol (E2) less than 1.9 pg.ml-1, SD 1.1 (normally 1.0-10.0 pg.ml-1). After a 21-km run, all salivary steroids appeared to increase. Mean salivary testosterone levels increased by 15.2% and salivary progesterone by 14.8%. Mean salivary oestrogens also increased (E1: +13.9%; E2: +21.1%). These findings confirm the results of earlier studies which found higher post-exercise plasma sex steroid levels. Since salivary measurements are believed to reflect non-protein-bound, thus free steroid levels, the results obtained by these techniques may provide a more realistic picture of the hormonal effects of physical exercise. In future, more accurate, cost-effective and easier techniques for salivary measurements may offer additional advantages.

Linear regression analysis of ultrasound follicular growth series: statistical relationship of growth rate and calculated date of growth onset to total growth period

Linear regression analysis was used to assess the serial growth of carefully measured individual mean follicular diameters as a function of menstrual age in a group of normal volunteers in natural, unstimulated cycles (n = 18). Follicle diameter (FD) growth, as measured with serial pelvic ultrasonography, can be shown to be essentially linear (mean R2, 0.92) with respect to time up to the point of ovulation. Growth rate (k) and the calculated date of growth onset (Do) are obtainable from the individual regression equations. Because an approximation of the date of ovulation (Dov, measured by menstrual age at the date of peak mean follicular size) is an available parameter, total growth period (TGP) is calculated with the equation (TGP = Dov - Do). Do, k, and TGP are highly correlated with one another. The mean parameters (+/- standard deviation) are Do = 4.29 +/- 2.77 day, k = 0.24 +/- 0.07 cm/day, TGP = 10.32 +/- 2.35 day, peak FD = 2.34 +/- 0.28 cm, and Dov = 14.61 +/- 2.00 day. The internal correlation of these parameters predicts that information from the first several scans in an individual series may be used to forecast date of ovulation. This may represent an improvement over the use of follicle size or menstrual age alone in planning for human chorionic gonadotropin administration, insemination timing, follicular aspiration and other interventions.

Ovulatory disturbances in patients with luteal insufficiency

In order to study ovulatory disturbances in patients with luteal insufficiency we evaluated 210 cycles of 170 women from infertile couples by ultrasonographic follicle measurements and hormonal determinations. Only cycles with evidence of luteinization were included into the study. Mid-luteal progesterone (P) levels were determined in relation to the ultrasonographic ovulation time or, where the follicle failed to rupture, in relation to the LH peak. In spontaneous cycles with a mid-luteal P level below 32 nmol/l (10 ng/ml) a luteinized unruptured follicle (LUF) was found in 71.1% of cycles, whereas in spontaneous cycles with a mid-luteal P level above 32 nmol/l only 7.9% cycles exhibited a failure of the follicle to rupture. The same phenomenon was encountered in cycles in which agents had been given to induce ovulation. The incidence of LUF cycles in an average infertility population could be calculated to be as high as 50% if the mid-luteal P level is below 32 nmol/l and as low as 4% if the mid-luteal P level is above 32 nmol/l. The geometric mean mid-luteal P level in spontaneous LUF cycles was 32.5 nmol/l, compared to 55.2 nmol/l in spontaneous ovulatory cycles (P less than 0.001). We conclude that in patients with luteal insufficiency a high incidence is found of a failure of the follicle to rupture. The entrapment of the oocyte in the unruptured follicle constitutes an important cause of infertility in these patients.

Precise day of ovulation determined by real-time ultrasound evidence of graafian follicular development

Real-time ultrasonic scanning was performed in 21 infertile Japanese women during 37 menstrual cycles. The maximum diameter prior to ovulation was 23.3 +/- 2.9 mm in spontaneous ovulation cycles, 29.6 +/- 5.2 mm in case of clomiphene therapies, and 26.7 +/- 3.9 mm in HMG-HCG therapies, respectively. Size of the graafian follicles was maximum at almost the same time as the LH peak in the plasma and urine, respectively. The LH peak in the urine was determined by the hemagglutination inhibition assay, the results of which were obtainable within 2 h. Four patients became pregnant (19.0%). There was no statistical correlation between the diameter of the largest follicle and the plasma estradiols (r = 0.28, 0.2 less than P less than 0.3) or between the diameter of the largest follicle and the peak luteinising hormone level (r = 0.27, 0.3 less than P less than 0.4). Therefore, the combination of the real-time ultrasound and a hemagglutination inhibition assay for LH in urine can be clinically applied to detect the precise day of the ovulation.