An evaluation of the method of Cox for the rapid analysis of pregnanediol in urine by gas-liquid chromatography

Rapid UHPLC-MS/MS measurement of pregnanediol 3-glucuronide in spot urine samples for detecting ovulation

Biochemical confirmation of ovulation typically involves measuring serum progesterone levels during the mid-luteal phase. Alternatively, this information could be obtained by monitoring urinary excretion of conjugated metabolites of ovarian steroids such as pregnanediol 3-glucuronide (PDG) using immunoassay techniques that have methodological limitations. The aim of the present study was to develop a mass spectrometry (MS)-based method for the rapid and accurate measurement of urinary PDG levels in spot urine samples. A "dilute and shoot" ultra-high-performance liquid cromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed for measuring PDG urinary concentration with a 6-min analysis time. The method underwent validation in accordance with ISO 17025 documentation for quantitative methods, proving an efficient separation of PDG from other structurally similar glucuro-conjugated steroid metabolites and ensuring a sufficient sensitivity for detecting the target analyte at concentrations as low as 0.01 μg/mL. The validation protocol yielded satisfactory results in terms of accuracy, repeatability, intermediate precision, and combined uncertainty. Additionally, the stability of both the samples and calibration curves was also conducted. The application to real urine samples confirmed the method's capability to measure PDG levels throughout an entire menstrual cycle and detecting ovulation. The rapidity of the analytical platform would therefore enable high throughput analysis, which is advantageous for large cohort clinical studies.

Direct measurement of pregnanediol 3-glucuronide (PDG) in dried urine spots by liquid chromatography-mass spectrometry to detect ovulation

BACKGROUND

Non-invasive self-testing using an objective chemical method to detect ovulation is valuable for women planning conception, practising contraception or undergoing infertility investigations or treatment.

METHODS

Based on luteal phase secretion of progesterone (P₄) and excretion of its major metabolite, pregnanediol glucuronide (PDG), we developed a novel direct liquid chromatography-mass spectrometry (LCMS) method to measure PDG and other steroid glucuronides in urine and in dried urine spots (DUS) without deconjugation or derivatization. Urine PDG by LCMS and immunoassay (P3G) and P₄ by immunoassay with and without adjustment for creatinine were evaluated in daily first void urine samples from 10 women through a single menstrual cycle in which ovulation was confirmed by serial transvaginal ultrasound.

RESULTS

Urine PDG with and without creatinine adjustment was stable during the follicular phase with the expected striking rise in the luteal phase peaking at 5 days after ovulation. Using a single spot urine sample (100 μL) or a DUS (<20 μL urine) and an optimal threshold to distinguish pre- from post-ovulatory samples, in ROC analysis urine PDG adjusted for creatinine accurately identified ovulation in 92 % of samples was comparable with P3G immunoassay and superior to urine P₄ with or without adjustment for creatinine. Extending the analysis to two or three consecutive daily samples reduced the false negative rate from 8% to 2.6 % for two and 1.9 % for three urine samples.

CONCLUSIONS

This method holds promise as a non-invasive self-test method for women to determine by an objective chemical method their ovulatory status.

The Use of Estrone-3-Glucuronide and Pregnanediol-3-Glucuronide Excretion Rates to Navigate the Continuum of Ovarian Activity

The patterns of a woman's normal ovarian activity can take many forms from childhood to menopause. These patterns lie on a continuum ranging from no ovarian activity to a fully fertile ovulatory cycle, but among the other defined patterns are cycles with anovulatory ovarian activity, including luteinized unruptured follicles (LUFs), and ovulatory cycles with deficient or short luteal phases. For any woman, these patterns can occur in any order, and one can merge into the next, without an intervening bleed, or be missed entirely. Consequently, it is not yet possible to predict the pattern of a future cycle, but it is possible to use our knowledge of the continuum to interpret the current cycle, which has clear implications for the management of personal fertility. An individual's position in the continuum can be monitored directly in real time by daily monitoring of ovarian hormone excretion rates, without either calendar-type calculations or reference to population means and standard deviations. The excretion of urinary estrone glucuronide (E1G) gives a direct measure of follicular growth, and the post-ovulatory rise in urinary pregnanediol glucuronide (PdG) following an E1G peak provides good evidence of ovulation. Specific values of the PdG excretion rate can be used to determine whether a cycle is anovulatory with or without a LUF, or is ovulatory and infertile or ovulatory and fertile. These specific values are important signposts for navigating the continuum. For a woman to take advantage of the knowledge of the continuum, the data must be reliable, and their interpretation has to be based on the underlying science and provided in an appropriate form. We discuss the various factors involved in acquiring and providing such information to enable each woman to navigate her own reproductive life.

Establishment of a reference ELISA for measurement of universal thresholds of pregnanediol glucuronide excretion rates using urine samples diluted to a constant volume per unit time

An enzyme-linked immunosorbent assay (ELISA) for measurement of pregnanediol-3α-glucuronide (PdG) excretion rates in urine samples diluted to 150 mL/h before analysis is described. The sensitivity of the 9 optimized standard curves was 0.093 ± 0.070 μmol PdG/24 hr, with the multiple combined standard curves having a mean mid-point (EC₅₀) of 6.88 μmol PdG/24 hr. The PdG threshold excretion rate of 7.0 μmol/24 hr, which is used as a marker for the end of fertility, was situated in the most accurate region of the standard curve. The specificity of the ELISA was determined using normal variate transformation to compare seven menstrual cycle profiles obtained with the ELISA method with the profiles obtained previously using a validated radioimmunoassay (RIA) method. The cycle profiles all agreed within experimental error, and a high degree of correlation using Deming regression was obtained. The correlation equation was Y = 1.57X-0.11 μmol PdG/24 hr (n = 200; r = 0.932). The PdG excretion rates determined by the ELISA were 50% higher than given by RIA, but the normal ranges were similar to those given by the original reference gas liquid chromatographic method. The ELISA assay was therefore suitable as a reference method for measurement of thresholds of PdG excretion rates.

Types of ovarian activity in women and their significance: the continuum (a reinterpretation of early findings)

BACKGROUND

There are many types of ovarian activity that occur in women. This review provides information on the relationship between the hormone values and the degree of biological response to the hormones including the frequency and degree of uterine bleeding. The continuous process is termed the ‘Continuum’ and is thus similar to other processes in the body.

METHODS

This review draws on information already published from monitoring ovarian activity by urinary oestrogen and pregnanediol measurements using timed 24-h specimens of urine. Much of the rationalization was derived from 5 to 6 year studies of girls progressing from childhood to adulthood, women progressing through menopause, and the return of fertility post-partum. During these times, all the reported types of ovarian activity were encountered.

RESULTS

All cycle types can be understood in terms of steps in the normal maturation of fertility at the beginning of reproductive life, its return post-partum and its demise at menopause. Each step merges into the next and therefore the sequence is termed the ‘Continuum’. Unpredictable movement from fertile to infertile types and back can occur at any time during reproductive life. Stress is a major causative factor. Hormonal definitions for each step, the relevance of the various cycle types in determining fertility and in the initiation of uterine bleeding and the roles of the pituitary hormones in causing them, are presented.

CONCLUSIONS

The findings explain the erratic fertility of women and why ovulation is not always associated with fertility. They provide an understanding of the various types of ovarian activity and their relation to pituitary function, fertility and uterine bleeding.

Use of defined estrone glucuronide-hen egg white lysozyme conjugates as signal generators in homogeneous enzyme immunoassays for urinary estrone glucuronide

Three structurally characterized estrone glucuronide-lysozyme conjugates, E1 (a 60:40 mixture acylated at K3 and K97), E3 (acylated at K33), and E5 (acylated at both K33 and K97) were isolated and purified using a combination of cation-exchange chromatography on S-sepaharose in 7M urea and hydrophobic interaction chromatography on butyl sepharose. Urea was essential to separate the conjugates into six chromatographically homogeneous fractions. In the absence of urea, complex mixtures of lysozyme and the six conjugate fractions were always encountered. The E1, E3, and E5 conjugates were highly inhibited by a sheep polyclonal anti-estrone glucuronide antibody only after the hydrophobic interaction chromatography step. The high level of inhibition enabled all three conjugates to be utilized as signal generators in homogenous enzyme immunoassays for urinary estrone glucuronide. Despite the apparently higher affinity of E3 for the antibody, both E1 and E3 gave standard curves that were indistinguishable provided that 1.7-fold more antiserum was used for E1. Both E1 and E3 yielded menstrual cycle urinary data that agreed with that provided by the Ovarian Monitor pre-coated assay tubes. Although, the menstrual cycle pattern was similar for the three signal generators, the E1G excretion rates yielded by E5 as the signal generator were only 60% of the reference values. Despite structural differences, there was no advantage gained in separating E1 and E3, but higher substituted conjugates such as E5 need removal for best assay performance.

Hormonal monitoring of ovarian activity using the Ovarian Monitor, part I. Validation of home and laboratory results obtained during ovulatory cycles by comparison with radioimmunoassay

A study was conducted to determine the accuracy and reliability of the Home Ovarian Monitor for measuring estrone glucuronide (E1G) and pregnanediol glucuronide (PdG) during ovulatory cycles as a means of monitoring ovarian activity. Approximately 60 ovulating women in three centres collected timed specimens of urine (3h or more) for a total of six cycles each. The women measured the E1G and PdG excretion per 24h in their urine specimens using the Monitor. A local laboratory using the Monitor also measured the excretion. Urine specimens from 18 to 19 cycles were sent frozen to the WHO Reference Laboratory in London where they were analysed for E1G and PdG by the Monitor and by radioimmunoassay (RIA). The correlation coefficients between the Monitor and radioimmunoassay results obtained in London were better than 0.84 in 80% of the cycles. A urine bias caused the Monitor E1G results to be higher than those obtained by radioimmunoassay but the daily patterns were the same. In 50% of the cycles, this bias caused a delay of up to 3 days in identifying the beginning of the E1G rise compared with radioimmunoassay. Timing of the preovulatory E1G peak and the postovulatory PdG rise agreed within the experimental errors of the two systems. The study confirmed that women using the Monitor at home obtained results that were as accurate as those obtained by laboratory procedures. Careful supervision was required to maintain laboratory levels of quality control and interpretation of results.

Definition of the potentially fertile period from urinary steroid excretion rates. Part II. A threshold value for pregnanediol glucuronide as a marker for the end of the potentially fertile period in the human menstrual cycle

Application of time series analysis to a database containing serial pregnanediol data from 113 complete ovulatory menstrual cycles contributed by 83 women of proven fertility and 68 cycles for which pregnanediol values were available over the ovulatory period, detected the first statistically significant risk in pregnanediol excretion for all cycles for which a baseline was available (n = 170). However, even at the 99% confidence level, for 22% of cycles a rise was observed before the presumed day of ovulation. Therefore, a threshold value for pregnanediol was sought from the database as a better marker for the end of fertility. A value of 1.4 mg per 24 h was not reached before day 2 after the pre-ovulatory estrogen peak day for 96% of the cycles. In the remaining 4% of cycles it was reached one day after the total estrogen peak day. The validity of this threshold was confirmed in extensive studies using the Ovarian Monitor where the equivalent is 6.3 mumol per 24 h of pregnanediol glucuronide and measurements are performed on timed urine specimens with a minimum collection time of three hours. These studies were as follows: 1) a World Health Organization study on the use of the Ovarian Monitor as a fertility self test in the home (108 cycles), 2) a multicenter study on returning fertility during breast feeding conducted by Family Health International (73 women), and 3) the general application of the Ovarian Monitor for pregnancy achievement and avoidance during the past ten years (over 250,000 PdG assays performed in ten countries). With rare exceptions, the use of these threshold values is applicable for all women provided correction is made for urine volume.

Effects of age and non-hormonal contraception on menstrual cycle characteristics

The objective of this study was to investigate the effects of age and non-hormonal contraceptive method on menstrual cycle parameters. The menstrual cycle data were collected prospectively, and the study was cross-sectional with regard to age. The subjects were 142 women, including 14 asymptomatic volunteers and 128 women who presented to a premenstrual tension (PMT) clinic. The age range was 20-45 years. Contraceptive methods used were intrauterine device (IUD) (n = 12), tubal ligation (n = 61) and non-intensive methods (n = 69). Daily menstrual cycle diaries were used to calculate cycle length and number of days of menstruation. Daily 24-h urine collections were used to calculate the day of the preovulatory estrogen peak. Pearson correlations found significant relationships between age and preovulatory estrogen peak day (p < 0.001) and length of cycle (p < 0.002), but not between age and length of menstruation or luteal phase. Analysis of variance was highly significant for age and contraceptive method, for both cycle length and preovulatory estrogen peak day. Non-intrusive contraception users aged 30 years and younger had significantly longer follicular phases than did women with tubal ligation (p < 0.05). It was concluded that cycle length decreases with age due to shortening of the follicular phase. Further research on whether tubal ligation affects ovulation and follicular phase length in young women is needed.

Menstrual cycle hormonal profiles of women with and without premenstrual syndrome

This paper compares the urinary hormone profiles of estrogen and pregnanediol in women with documented premenstrual syndrome (PMS) (n = 65) and asymptomatic volunteers (n = 18). Daily 24-h urine samples were collected for an entire menstrual cycle. Subject groups did not differ significantly in menses length or in the day of the preovulatory estrogen peak. Cycle length was significantly shorter for the volunteers (p < 0.05). The day of the pregnanediol peak occurred significantly later for the PMS patient group than for the asymptomatic volunteers (p < 0.05). Split plot analysis of variance showed no significant differences overall between subject groups for levels of urinary estrogen or pregnanediol. This study did not find evidence of progesterone deficiency amongst sufferers of the premenstrual syndrome.

Application of time-series analysis for the recognition of increases in urinary estrogens as markers for the beginning of the potentially fertile period

Time-series analysis was applied to the urinary total estrogen data from 142 ovulatory menstrual cycles to determine the first statistically significant increase as a marker for the beginning of the potentially fertile phase. Application of the Trigg's tracking signal to each cycle detected an increase in urinary total estrogens above the baseline in every case, with a cumulative probability of > or = 95%. The distribution of first increase days ranged from 10 days before 3.5 days before the presumed day of ovulation with a mean of 6.5 +/- 1.4 days. The significant parameters in the calculation of the tracking signal are the smoothing constant (alpha) which is related to the number of baseline observations, the baseline mean for the cycle, and the variation of the baseline mean. The method allows a calculation of the tracking signal as the cycle unfolds and a statistical assessment can be given each day. The procedure is easily adaptable for computer calculation, and because it is applied to individual cycles avoids the use of population means with the loss of information inherently associated with the combination of data from many cycles. The Trigg's tracking signal is an appropriate method of analysis of menstrual cycle data and represents a satisfactory alternative to the more usual cumulative sum procedure. The distribution of the first increases constitutes a reference standard for urinary estrogen assays.

Post-tubal sterilization problems correlated with ovarian steroidogenesis

Mid-luteal phase total urinary oestrogen excretion was found to be significantly reduced in women who had previously undergone tubal sterilization at least two years before assay; pregnanediol levels at or below 2.0 mg/24 hrs were significantly more frequent for the study group. These findings indicate that reduced ovarian function is associated with that procedure. The major problems declared as having been experienced subsequent to tubal sterilization were classified into three categories; some women declared problems in more than one category: (1) Abnormal uterine bleeding and/or menorrhagia, (2) Physical problems, (3) Psychological and/or psychiatric problems. Category 1 was associated with a significant fall in total oestrogen excretion, and category 2 with a significant fall in both total oestrogen and pregnanediol excretion. Analysis of category 3 will be published elsewhere. A negative correlation between total oestrogens and cholesterol was observed.

Natural family planning

It is now well accepted that a woman can conceive from an act of intercourse for a maximum of only about 7 days of her menstrual cycle. The reliability of natural family planning depends on identifying this window of fertility without ambiguity. Several symptomatic markers, cervical mucus and basal body temperature, have been used extensively and with considerable success in most women but failures occur. Ovarian and pituitary hormone production show characteristic patterns during the cycle. Urinary estrogen and pregnanediol measurements yield reliable information concerning the beginning, peak, and end of the fertile period, provided that the assays are accurate and performed on timed specimens of urine. We have developed such enzyme immunoassays for urinary estrogen and pregnanediol glucuronides that can be performed at home. In the early versions of the assays, enzyme reaction rates were measured by eye, but more recently, a simple photoelectronic rate meter has been used. The final problem to be solved is not technologic but whether women are sufficiently motivated to expend the same time and effort each day for 10 days a month, with less cost, on fertility awareness as they spend on making a cup of tea.

A study of returning fertility after childbirth and during lactation by measurement of urinary oestrogen and pregnanediol excretion and cervical mucus production

Longitudinal studies involving weekly measurement of urinary oestrogen and pregnanediol excretion were performed in 55 post-partum women to identify the patterns of returning fertility. The women kept diaries of breast-feeding episodes, mucus symptoms and times of bleeding; some recorded basal body temperature and acts of intercourse. The study represented a total time of 36 years (7·8 months per woman). The majority of the women were breast-feeding throughout the study. During lactation amenorrhoea, there was complete ovarian quiescence in two-thirds of the subjects and minimal cyclic activity in the others. The first bleeds were associated with anovulatory ovarian activity in 40% of the women, with normal ovulation in 19%, with ovulation but short luteal phases in 25% and with ovulation but deficient luteal phases in 16%. The incidence of normal ovulatory cycles increased with time after delivery and with the number of cycles after delivery and eventually reached 85% even though many women were still breast-feeding at the time. Twenty-two pregnancies occurred, fourteen being unplanned: eight women were fully breast-feeding at the time of conception. Mucus symptoms correlated with the hormone values in approximately 60% of cycles. However, some women had symptoms which were difficult to interpret during their early cycles or potential fertility was not indicated by raised mucus scores or the presence of the peak mucus symptom. These problems together with the resulting confusion appeared to be the major causes for the unplanned pregnancies. Methods for coping with these problems are discussed.

Urinary 6-sulphatoxy melatonin excretion during the human menstural cycle

The excretion of 6-sulphatoxy melatonin in urine has been shown to provide a reliable index of melatonin production in man. Daily measurements made in two healthy ovulating women showed that both the total amount excreted/day and the proportion excreted during the sleep period remained relatively constant for each subject throughout the menstrual cycle. These data do not support the view that there are changes in melatonin production which correlate with cyclical reproductive endocrine function in the human.

Monitoring induction of ovulation by rapid radioimmunoassays of oestrogen and pregnanediol glucuronides

To increase the sample-handling capacity for an induction of ovulation programme, direct urinary radioimmunoassays (RIA) for three steroid glucuronides, pregnanediol-3-glucuronide (Pd-3-G), oestrone-3-glucuronide (E1-3-G), and oestriol-16 alpha-glucuronide (E3-16-G), were established. Results obtained for urinary Pd-3-G measured by direct RIA show an excellent correlation (r = 0.98, N = 46) with those for urinary pregnanediol measured by gas-liquid chromatography. Estrone-3-glucuronide (E1-3-G) and estriol-16 alpha-glucuronide (E3-16-G) values, measured by direct RIA, closely paralleled the total urinary oestrogen measured fluorimetrically. Ovarian response to ovulation induction therapy can be monitored by observing the changes in the levels of E1-3-G in urine. Pre-ovulatory levels of urinary E3-16-G were found to be too low for use in this regard. Direct RIA for E1-3-G and Pd-3-G are recommended as reliable indices of ovarian function in the monitoring of patients receiving treatment for the induction of ovulation.

The significance of FSH elevation in young women with disorders of ovulation

High serum follicle stimulating hormone (FSH) values are consistent with ovarian failure. We studied the progress of 67 women aged under 35 years with oligomenorrhoea or secondary amenorrhoea in whom the serum FSH value was greater than 20 U/1. Twenty-four patients remained amenorrhoeic, but 17 ovulated and six conceived, two on two occasions. Coincident mean serum luteinising hormone (LH) concentrations were significantly lower and mean total urinary oestrogen concentrations were significantly higher in patients who subsequently ovulated, but the degree of increase in FSH did not correlate well with later ovarian function. Treatment with oestrogens, clomiphene citrate, human pituitary gonadotrophin, and bromocriptine was of no benefit in inducing an ovarian response while FSH concentrations remained raised. Our results suggest that a considerable proportion of younger women with ovulatory disorders associated with FSH values in the menopausal range will spontaneously resume ovulation and some will conceive.

Capillary gas chromatographic measurement of neutral urinary steroids: evaluation and comparison with alternative methodology

The major neutral urinary steroids have been quantitated by capillary gas chromatography and the reproducibility and accuracy of the method have been fully evaluated. Typical intra- and inter-assay coefficients of variation for individual steroids ranged from 4.9 to 10.1% and from 15.6 to 21.5%, respectively. Comparison of steroid values with alternate and commonly employed procedures for measuring urinary 17-oxosteroids, total 17-oxogenic steroids, and cortisol and plasma dehydroepiandrosterone-sulphate yielded correlation coefficients between 0.71 and 0.79. A definite relationship between serum cortisol and urinary trihydroxy-pregnanedione was also shown. Urinary androstenedione metabolites, however, could not be significantly (P greater than 0.05) correlated with the normalised androgen ratio in plasma.

An unexpectedly high rate of ectopic pregnancy following the induction of ovulation with human pituitary and chorionic gonadotrophin

Six tubal ectopic pregnancies occurred in a series of 193 pregnancies following ovulation induced with human pituitary gonadotropin (hPG) and human chorionic gonadotrophin (hCG). The ectopic pregnancy rate of 3.1 per cent is higher than quoted incidences in the general population and occurred in the absence of predisposing factors. There was an association between ectopic pregnancy and elevated urinary oestrogen excretion in the peri-ovulatory phases of the induced ovulatory cycles. A urinary oestrogen excretion of greater than 200 microgram/24 hours on day 0 (the day after hCG was given) was associated with a 10 per cent chance of ectopic pregnancy (P less than 0.05).

Time-course relationships between serum LH, serum progesterone and urinary preganediol concentrations in normal women

A specific and sensitive gas chromatographic method was used to investigate the concentration of pregnanediol glucuronide in urine in relation to the time of ovulation. Serum LH and progesterone concentrations in the same subjects were used as evidence for the occurrence of ovulation. The urinary concentration of pregnanediol glucuronide in 24-hour collections and in overnight specimens increased 2-fold or more from the day of the midcycle LH peak to the time of predicted ovulation (24-48 hour after the LH peak) in parallel with the rise in serum progesterone concentration.

Bromocriptine in the treatment of secondary amenorrhoea and ovarian dysfunction in hyper- and normo-prolactinaemic patients

The clinical use of bromocriptine (2.5 mg twice daily) was investigated in 40 women attending an infertility clinic and presenting with secondary amenorrhoea (18) or with ovarian dysfunction (22) which had failed to respond to anti-oestrogen therapy. Patients in each group were sub-divided into those with raised and those with normal prolactin levels, and re-examined at 3 and 12 months after the start of treatment. The results confirmed that bromocriptine is effective in the treatment of hyperprolactinaemic states whether there is amenorrhoea or not. Moreover, in cases of ovarian dysfunction as well as of amenorrhoea where the prolactin levels were within the normal range, there was evidence to suggest that bromocriptine can be associated with a return of ovulation, although the mechanism by which it might do so still needs evaluation.

Oestrogen and pregnanediol excretion through childhood, menarche and first ovulation

Urinary oestrogen and pregnanediol values were measured in 24 boys and 38 girls between the ages of 2 and 13 years. Longitudinal studies were conducted on eight girls, two of whom collected for periods of 4 and 5 years which included menarche and in one case establishment of ovulation. Highly sensitive assay methods were developed for measuring the very small amounts of oestrone, oestradiol and oestriol and pregnanediol present in the urine of young children. The total oestrogen values were within the submicrogram range of 0·1–0·5 μg/24 hr in the children aged 2–8 years, with no differences seen between the boys and girls. After the age of 8 years, oestrogen values above 1 μg/24 hr began to be encountered and by age 11½ years the majority of subjects were recording oestrogen values above this figure. The rise in the oestrogen values was more rapid in the girls than in the boys. Evidence was presented that a value of approximately 1 μg/24 hr represents the minimum oestrogen production for the initiation of breast development. The oestrogen values were fluctuating with irregular periodicities at all ages and the gradual general rises seen after the age of 8 years could be arrested at any stage for a year or more. Menarche was preceded by marked periodic fluctuations in oestrogen output which peaked above 15 μg/24 hr. In all subjects studied, the initial bleeding cycles were anovulatory as judged by the low pregnanediol values, the usual pattern being one of fluctuating oestrogen production. One subject was studied fully through to the establishment of ovulation, which first occurred 12 months after menarche. The approach of ovulation was indicated by pre-menstrual rises in pregnanediol which increased in amplitude from 0·4 mg/24 hr until finally 2 mg/24 hr was exceeded (the value accepted for ovulation). Evidence was presented that the interval from menarche to ovulation in different individuals was very variable, extending from ovulation at menarche itself to periods of more than a year. Recording of self-observed symptoms of production of cervical mucus could be of considerable value in documenting these events in larger populations.

Corpus luteum function in early pregnancy following ovulation induction with bromocriptine

Serum and prolactin levels and urinary oestrogen and pregnanediol excretion were measured during early pregnancy in 12 hyperprolactinaemic subjects who became pregnant during treatment with bromocriptine. Prolactin levels were suppressed below normal whilst taking the bromocriptine, but rose significantly when this drug was stopped and by eight weeks of gestation reached values significantly higher than those observed in normal pregnancy. Further increases in prolactin levels were, however, not observed. Urinary oestrogen and pregnanediol excretion was initially normal but, following cessation of bromocriptine, urinary pregnanediol excretion decreased and was significantly less than normal at 11 to 14 weeks gestation. These results suggest that elevated prolactin levels affect corpus luteum function of early pregnancy. Because the effect is maintained until at least 14 weeks gestation, prolactin may also affect progesterone production by the placenta.

A study of the effects of bromocriptine on serum prolactin, follicle stimulating hormone and luteinizing hormone and on ovarian responsiveness to exogenous gonadotrophins in anovulatory women

Twelve anovulatory patients with normal serum prolactin values and six with elevated values were treated with bromocriptine and the effects on serum prolactin, FSH and LH levels were recorded. Ovulation resulted in one patient who had normal prolactin values and in all six who had raised values. No patient with normal basal prolactin values showed an increase in serum FSH during therapy with bromocriptine, whereas 5 of the 6 patients with elevated values showed significant increases. Similar results were obtained for LH. Although these differences were highly significant (P less than 0-005) the majority of the serum FSH and LH values remained within the normal ranges. Five patients with normal basal prolactin values and one with elevated values were also treated with human pituitary gonadotrophin (HPG). An increase in ovarian responsiveness to HPG during therapy with bromocriptine was recorded in the one patient with initially elevated prolactin values. It was concluded that bromocriptine acts by allowing FSH to rise above threshold requirements for follicular stimulation.

Oestrogen excretion and ovarian pathology in postmenopausal women with atypical hyperplasia, adenocarcinoma and mixed adenosquamous carcinoma of the endometrium

Urinary oestrogen and pregnanediol excretion were measured before and after hysterectomy and bilateral salpingo-oophorectomy in 26 postmenopausal women with adenocarcinoma of the endometrium, 10 postmenopausal women with mixed adenosquamous carcinoma and 11 postmenopausal women with atypical hyperplasia (the patient groups). The results were compared with the values obtained in 22 active postmenopausal women, 20 hospitalized postmenopausal women and 18 women who had been subjected to hysterectomy and bilateral salpingo-oophorectomy for cancer of the cervix (the control groups). The ovaries and Fallopian tubes obtained at operation were examined for evidence of current or past excessive oestrogen production. Preoperative oestrogen values were higher in the patient groups than in the controls and the elevated values persisted after oophorectomy. The implications of these findings are discussed.

Serum prolactin levels and the value of bromocriptine in the treatment of anovulatory infertility

Basal serum levels of prolactin were measured in 37 infertile anovulatory patients who had failed to conceive on therapy with clomiphene citrate. Twenty of these patients, 16 of whom had galactorrhoea, had elevated basal serum prolactin values which were suppressed to normal or subnormal values during therapy with bromocriptine, the most commonly effective dose being 2.5 mg twice daily. Ovulation, as assessed by urinary oestrogen and pregnanediol measurements, was induced in 17 of these patients with pregnancy in 14. Ovarian responses short of defined criteria for ovulation were induced initially in eight patients, but these progressed to full ovulatory responses in five patients, either on the same or increased doses of bromocriptine. In all the patients who ovaulated, the prolactin levels had been reduced below the mean value for normal women (10.6 ng-ml). The three patients who failed to ovulate all had values higher than this at a dose of bromocriptine reaching 5.0 mg thrice daily. There seemed to be no value in increasing the dose of bromocriptine once ovulation had been achieved. Of the 17 patients with normal basal prolactin values, only one had an unequivocal response to bromocriptine with ovulation and conception, even though the prolactin values in the majority were suppressed to below normal.

The investigation of ovarian function by measurement of urinary oestrogen and pregnanediol excretion

Urinary oestrogen and pregnanediol excretion was measued daily ("daily monitoring") for a complete cycle in 20 normally menstruating women, in one patient with an anovulatory cycle and for 28 days in a patient with secondary amenorrhoea. The measurements were also performed on urine specimens collected at weekly intervals for 4 to 6 weeks ("weekly tracking") from 506 patients with evidence of abnormal ovarian function. These included 9 patients with primary amenorrhoea, 132 patients with secondary amenorrheoa, 138 patients with oligomenorrhoea and 227 patients with evidence of ovarian dysfunction and cycle lengths of 25 to 42 days. The results were subjected to statistical analysis. In the normal cycles, ovulation could be identified on the criteria of a rising pregnanediol value reaching or exceeding 2-0 mg. per 24 hours for a period of 7 days or more. Valid conclusions on the overall mean oestrogen and pregnanediol values for a complete cycle could be made from the results of weekly tracking, irrespective of which day the tracking commenced. Correlations were obtained by comparing the mean and maximum urinary oestrogen values and the variability of the values with the evidence of ovarian function indicated by the clinical classifications of the patients, the duration of the disorders and the subsequent occurrence of uterine bleeding. Mean oestrogen values of 10 mug. per 24 hours or less were associated with lack of ovarian function. For values higher than this a discriminant function based on both the mean oestrogen value and the variability of the oestrogen values was useful in predicting onset of spontaneous menstruation. A single urine specimen collected 4 to 8 days before onset of menstruation showing a raised pregnanediol value of 2-0 mg. per 24 hours or more provided a valid test for ovulation in women with regular cycles, and a single urine specimen giving an oestrogen value of 10 mug per 24 hours or less gave a valid indication of absent ovarian function in women with amenorrhoea for two years or more. In all other circumstances serial sampling at weekly intervals provided a valid assessment of ovarian activity. Application of these principles allows the greatest amount of information on ovarian function to be obtained with the greatest economy of effort.

Rapid analysis of pregnanediol in pregnancy urine

A simple, inexpensive, and rapid method for the determination of pregnanediol in pregnancy urine by gas liquid chromatography is described. Automatic injection of the samples into the gas chromatograph allows up to 36 samples to be run overnight thus saving valuable technical time.The method described can easily be adopted for use in a routine steroid laboratory. The results obtained by this method have been compared with values obtained by the method of Klopper, Michie, and Brown (1955).

Urinary Pregnanediol, Oestrogens, L.H. and F.S.H. during the Normal Menstrual Cycle

The determination of urinary hormones is useful in the assessment of gonadal and pituitary function. For interpretation of these parameters it is essential to establish normal values. This paper describes some of the methods used and results obtained in the determination of urinary pregnanediol, oestrogens, L.H. and F.S.H. during a number of normal cycles.