To appraise the physiological pattern(s) of episodic testosterone and FSH release in man, we withdrew blood samples at 10-min intervals for 24-36 h in a total of 15 normal men. We subjected the resulting FSH (15 men) and testosterone (5 men) time series to 3 statistically based and mathematically independent procedures for detecting hormone pulsatility, viz. Cluster analysis, the Detect program, and Fourier transformation. The Cluster technique disclosed discrete testosterone and FSH peaks occurring at mean (+/- SEM) interpulse intervals of 112 +/- 14 and 85 +/- 3.4 min, respectively. These values were not significantly different from the mean LH interpulse interval of 95 +/- 11 min. The average durations of the testosterone and FSH pulsations were 90 +/- 11 and 59 +/- 3 min, respectively. The mean testosterone pulse amplitude reached a maximal value of 910 +/- 92 ng/dL (31.5 +/- 3.2 nmol/L), which represented a mean increase of 242 +/- 26 ng/dL (8.4 +/- 0.9 nmol/L) above the preceding nadir. FSH pulses had a maximum of 7.2 +/- 0.3 IU/L, and an incremental amplitude of 1.3 +/- 0.1 IU/L. An independent pulse detection procedure. Detect, yielded a testosterone pulse frequency of 12.3 +/- 0.8 pulses/day [P = NS vs. Cluster program (13 +/- 1.9 pulses/day)]. The Cluster and Detect estimates of FSH pulse frequency were also similar, viz. 16 +/- 1.9 and 16 +/- 0.6 pulses/day. Further analysis by Fourier transformation revealed significant circadian periodicities for serum testosterone, FSH, and LH, which had mean nyctohemeral amplitudes of 185 ng/dL (6.4 nmol/L), 0.38 IU/L, and 1.3 IU/L, respectively. Cross-correlation analyses disclosed significantly positive uncorrected cross-correlations between LH and testosterone that were maximal at a testosterone lag of 60 min (range, 50-70 min). To eliminate high intrinsic autocorrelations within the testosterone and LH time series, stepwise autoregressive fitting was employed. The resulting partial cross-correlation matrices indicated that LH concentrations at any given instant were significantly positively correlated to testosterone concentrations lagged by 10 and 20 min. Similarly, contemporaneous LH and FSH concentrations were significantly positively correlated (r = 0.40-0.89; P less than 0.001). Moreover, autoregressive modeling disclosed significantly positive partial cross-correlations between LH and FSH at a FSH lag of 10 min. In summary, we have identified significant pulsatile as well as circadian (24-h) patterns of testosterone and FSH release in normal men.(ABSTRACT TRUNCATED AT 400 WORDS)
The congenital aplasia or severe hypoplasia of mullerian structures is infrequent. However, the features of normal female endocrine function paired with the absence of a functional uterus and vagina makes it a fascinating entity. The diagnosis and work-up in these patients has become very efficient, thanks to the use of imaging, and there are multiple successful procedures for the creation of a neovagina. In recent years, infertility treatment options through in vitro fertilization have also become available as part of the long-term care of these patients.
To define the physiological relationships between episodic progesterone and LH release, we measured serum progesterone and LH concentrations in blood sampled at 10-min intervals for 24 h in seven young women in the midluteal phase of the menstrual cycle. The resultant time series were assessed further by Fourier transformation, Cluster analysis, and cross-correlation analysis with autoregressive modeling. These techniques permitted an examination of circadian rhythms, discrete (ultradian) pulse properties, and simultaneous or lagged correlations between progesterone and LH release. We found the following. 1) Both serum LH and progesterone concentrations had significant circadian periodicities, with similar acrophases (times of maximal nyctohemeral values). LH and progesterone also manifested multiple ultradian rhythms of similar periodicities (range, 48-241 min). 2) Discrete serum progesterone peaks occurred at a mean interpulse interval of 118 +/- 12 (+/- SE) min, had durations of 92 +/- 12 min, and had incremental amplitudes of 4.3 +/- 0.9 ng/mL (14 +/- 3 nmol/L). The frequency and duration characteristics of the progesterone and LH peaks were not significantly different, but progesterone fractional peak amplitudes were one quarter those of LH pulses. 3) Fractional progesterone peak amplitudes in the seven women correlated inversely (r = -0.811) with 24-h mean LH concentrations, suggesting a negative feedback relationship between progesterone and LH release. 4) LH and progesterone interpulse intervals both exhibited significant nyctohemeral variations, with diurnal amplitudes of 73 +/- 12 min for LH and 43 +/- 8.9 min for progesterone (P less than 0.01). 5) Significant positive cross-correlations existed in all seven women between serum LH and progesterone concentrations considered simultaneously and at progesterone time lags of 10-50 min. By autoregressive modeling, the later (20-50 min) cross-correlations could be accounted for by sustained autocorrelations in the individual progesterone and LH time series and significant cross-correlations between LH and simultaneous progesterone concentrations and between LH and 10-min lagged progesterone concentrations. We conclude that progesterone release occurs in a periodic (circadian and ultradian) fashion as well as in a discrete (episodic or pulsatile) mode. Moreover, both positive and negative feedback relationships operate to coordinate LH and progesterone secretion in the midluteal phase of the human menstrual cycle.
With increasing rates of diagnosis of childhood cancers and the evolution of more effective treatment options resulting in prolonged life spans, fertility preservation counseling is an integral component of the discussion at the time of diagnosis of childhood cancers. The primary fertility preservation option that exists for prepubertal girls is ovarian tissue cryopreservation. Although ovarian tissue cryopreservation is still considered to be experimental in nature, live births have resulted from orthotopic tissue transplantation. Fertility preservation should be offered to all prepubertal girls at high-risk for premature ovarian failure as a result of gonadotoxic treatment. Ethical and legal questions surrounding these issues must be considered as more and more pediatric patients pursue fertility preservation.
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