Plasma Testosterone Levels During the Menstrual Cycle A. VALETTE, B. SERADOUR, AND J. BOYER Unite Metabolique, Centre Hospitalier Regional de Marseille, Hopital de la Conception, 13385 Marseille Cedex 4, France to the time of day, or to the phase of the menstrual cycle. The overall concentration of plasma testosterone throughout the menstrual cycle in the 8 women studied was 40 ± 16 ng/100 ml (n = 89). (J Clin Endocrinol Metab 40: 160, 1975)
ABSTRACT. Utilizing a radioimmunoassay, plasma testosterone was measured 3 times daily in 8 normal women for 3-4 consecutive days at the onset, middle and end of the menstrual cycle. No variation of the level of testosterone in plasma could be related
IMITED information is available concerning the pattern of plasma androgen levels in women. Whether or not a cyclic production of testosterone (T) occurs during the menstrual cycle has not been firmly established. This report describes the measurement of plasma T in 3 daily blood samples at different phases of the menstrual cycle in 8 healthy women. Statistical analysis showed there was no consistent pattern of T concentrations in all the cycles studied.
L
tently found to be less than 10 ng/100 ml. The interassay coefficient of variation in our laboratory is 10.3%.
Results Figure 1 shows the T concentration in the plasma of women during the menstrual cycle. Statistical analysis indicated that the variation of T concentration in plasma was not affected by the phase of the cycle. Paired t tests were carried out on the values obtained at the same time of the day (0900, 1600 and 2200 hr) at different phases of the cycle (onset-middle,
Materials and Methods
>TEROI
r
ioo
Eight healthy women (18-32 yr) with regular >0900 (3600 02200 menstrual cycles of normal duration (26-30 days) were studied. All women demonstrated a rise of basal Time of blood collection (hours) body temperature between day 12 and day 16 of the O) 70 menstrual cycle. Blood samples were collected from c n-9 each subject at 0900, 1600 and 2200 hr during 11:11 LJJ 3-4 consecutive days at the onset (days 3-8), middle 60 (days 11-16) or end (days 23-28) of the cycle. One subject participated 3 times (days 6-8, 12-14 and 50 25-28), another subject twice (days 4 - 6 and 24-26) during the same menstrual cycle. \JJ Testosterone (T) was quantitated on duplicate O 40 aliquots of peripheral venous plasma by a radioimmunoassay (1). Rabbit antibodies were raised against LJJ T-3-oxime conjugated to bovine serum albumin (2). f - 30 These antibodies cross-reacted 75% with dihydrotestosterone and 25% with A4-androstenediol. Extraction 20 and purification of T were carried out according to Rosenfield et al. (3). The mean recovery of 3H-T added to 2 ml plasma samples was 75 ± 7% SD 10 (n = 89). In five reference curves run in a single assay series, the means ± SD of the percent of bound T for the 0, 50, 100, 200 and 400 pg standards Onset End Middle were 78.4 ± 1.4%, 65.5 ± 1.2%, 55.0 ± 1.9%, 41.2 ± 2.0% and 30.1 ± 2.4%. 2 ml saline systematically PHASE OF THE MENSTRUAL CYCLE carried through the entire procedure with each series' FIG. 1. Mean plasma concentrations of testosterone of plasma samples gave blanks which were consisat 3 phases of the menstrual cycle in 8 women; n is the number of observations; brackets indicate the standard error. Received March 4, 1974.
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COMMENTS middle-end, onset-end). Differences were all not significant. No consistent pattern of variation of plasma T could be either demonstrated by separate analysis of the data obtained from the single subject who participated three times during the same menstrual cycle. No circadian rhythm of the level of plasma T could be demonstrated at any phase of the menstrual cycle, although a considerable intra-individual variability in levels was noted. As calculated from the 3 daily blood samples, the mean concentration (ng/100 ml) of plasma T were 42 ± 18 (n = 31), 33 ± 12 (n = 32) and 43 ± 17 (n = 26) at the onset, middle and end of the menstrual cycle, respectively. The overall concentration of T in plasma throughout the cycles in the 8 women studied was 40 ± 16 ng/100 ml (n = 89).
in 3 daily blood samples obtained for at least 3 consecutive days at different phases of the human menstrual cycle. On this basis, the variation of plasma T levels appeared to be random in nature. However, the relatively large intraand interindividual variation of plasma T levels, along with the small number of subjects studied, may have contributed to mask variations of small amplitude related to the time of day, to the phase of the menstrual cycle, or both.
Discussion
References
Conflicting data have been reported as to the concentration of T in plasma of adult women. In 1964, Lobotsky et at. (4) measured plasma T levels in 9 women during 17 cycles and found a significant rise at midcycle. A similar observation has been made recently by Judd and Yen (5), who measured the concentration of plasma T during 6 normal menstrual cycles. In contrast, Dupon et al. (6) studying 5 normal menstrual cycles found no distinct rhythm in plasma T levels. The present work is the first in which plasma T levels were measured
Acknowledgments The skillful assistance of D. Martel is gratefully acknowledged. This research was supported by a grant from la Direction Generale de la Sante (Problemes Medicaux de la Maternite, de l'Enfance et de l'Education Sanitaire).
1. Furuyama, S., D. M. Mayes, and C. A. Nugent, Steroids 16: 415, 1970. 2. Erlanger, B. F., F. Borek, S. Beiser, and S. L. LiebermanJ Biol Chem 228: 713, 1957. 3. Rosenfield, R. L., W. R. Eberlein, and A. M. Bongiovanni, J Clin Endocrinol Metab 29: 854, 1969. 4. Lobotsky, J. H., H. I. Wyss, E. J. Segre, and C. W. LloydJ Clin Endocritiol Metab 24: 1261, 1964. 5. Judd, H. L., and S. S. C. Yen, J Clin Endocrinol Metab 36: 475, 1973. 6. Dupon, C , A. Hosseinian, and M. H. Kim, Steroids 22: 47, 1973.
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 02 August 2016. at 11:59 For personal use only. No other uses without permission. . All rights reserved.
ABSTRACT. Utilizing a radioimmunoassay, plasma testosterone was measured 3 times daily in 8 normal women for 3-4 consecutive days at the onset, middle and end of the menstrual cycle. No variation of the level of testosterone in plasma could be related
IMITED information is available concerning the pattern of plasma androgen levels in women. Whether or not a cyclic production of testosterone (T) occurs during the menstrual cycle has not been firmly established. This report describes the measurement of plasma T in 3 daily blood samples at different phases of the menstrual cycle in 8 healthy women. Statistical analysis showed there was no consistent pattern of T concentrations in all the cycles studied.
L
tently found to be less than 10 ng/100 ml. The interassay coefficient of variation in our laboratory is 10.3%.
Results Figure 1 shows the T concentration in the plasma of women during the menstrual cycle. Statistical analysis indicated that the variation of T concentration in plasma was not affected by the phase of the cycle. Paired t tests were carried out on the values obtained at the same time of the day (0900, 1600 and 2200 hr) at different phases of the cycle (onset-middle,
Materials and Methods
>TEROI
r
ioo
Eight healthy women (18-32 yr) with regular >0900 (3600 02200 menstrual cycles of normal duration (26-30 days) were studied. All women demonstrated a rise of basal Time of blood collection (hours) body temperature between day 12 and day 16 of the O) 70 menstrual cycle. Blood samples were collected from c n-9 each subject at 0900, 1600 and 2200 hr during 11:11 LJJ 3-4 consecutive days at the onset (days 3-8), middle 60 (days 11-16) or end (days 23-28) of the cycle. One subject participated 3 times (days 6-8, 12-14 and 50 25-28), another subject twice (days 4 - 6 and 24-26) during the same menstrual cycle. \JJ Testosterone (T) was quantitated on duplicate O 40 aliquots of peripheral venous plasma by a radioimmunoassay (1). Rabbit antibodies were raised against LJJ T-3-oxime conjugated to bovine serum albumin (2). f - 30 These antibodies cross-reacted 75% with dihydrotestosterone and 25% with A4-androstenediol. Extraction 20 and purification of T were carried out according to Rosenfield et al. (3). The mean recovery of 3H-T added to 2 ml plasma samples was 75 ± 7% SD 10 (n = 89). In five reference curves run in a single assay series, the means ± SD of the percent of bound T for the 0, 50, 100, 200 and 400 pg standards Onset End Middle were 78.4 ± 1.4%, 65.5 ± 1.2%, 55.0 ± 1.9%, 41.2 ± 2.0% and 30.1 ± 2.4%. 2 ml saline systematically PHASE OF THE MENSTRUAL CYCLE carried through the entire procedure with each series' FIG. 1. Mean plasma concentrations of testosterone of plasma samples gave blanks which were consisat 3 phases of the menstrual cycle in 8 women; n is the number of observations; brackets indicate the standard error. Received March 4, 1974.
160
The Endocrine Society. Downloaded from press.endocrine.org by [${individualUser.displayName}] on 02 August 2016. at 11:59 For personal use only. No other uses without permission. . All rights reserved.
161
COMMENTS middle-end, onset-end). Differences were all not significant. No consistent pattern of variation of plasma T could be either demonstrated by separate analysis of the data obtained from the single subject who participated three times during the same menstrual cycle. No circadian rhythm of the level of plasma T could be demonstrated at any phase of the menstrual cycle, although a considerable intra-individual variability in levels was noted. As calculated from the 3 daily blood samples, the mean concentration (ng/100 ml) of plasma T were 42 ± 18 (n = 31), 33 ± 12 (n = 32) and 43 ± 17 (n = 26) at the onset, middle and end of the menstrual cycle, respectively. The overall concentration of T in plasma throughout the cycles in the 8 women studied was 40 ± 16 ng/100 ml (n = 89).
in 3 daily blood samples obtained for at least 3 consecutive days at different phases of the human menstrual cycle. On this basis, the variation of plasma T levels appeared to be random in nature. However, the relatively large intraand interindividual variation of plasma T levels, along with the small number of subjects studied, may have contributed to mask variations of small amplitude related to the time of day, to the phase of the menstrual cycle, or both.
Discussion
References
Conflicting data have been reported as to the concentration of T in plasma of adult women. In 1964, Lobotsky et at. (4) measured plasma T levels in 9 women during 17 cycles and found a significant rise at midcycle. A similar observation has been made recently by Judd and Yen (5), who measured the concentration of plasma T during 6 normal menstrual cycles. In contrast, Dupon et al. (6) studying 5 normal menstrual cycles found no distinct rhythm in plasma T levels. The present work is the first in which plasma T levels were measured
Acknowledgments The skillful assistance of D. Martel is gratefully acknowledged. This research was supported by a grant from la Direction Generale de la Sante (Problemes Medicaux de la Maternite, de l'Enfance et de l'Education Sanitaire).
1. Furuyama, S., D. M. Mayes, and C. A. Nugent, Steroids 16: 415, 1970. 2. Erlanger, B. F., F. Borek, S. Beiser, and S. L. LiebermanJ Biol Chem 228: 713, 1957. 3. Rosenfield, R. L., W. R. Eberlein, and A. M. Bongiovanni, J Clin Endocrinol Metab 29: 854, 1969. 4. Lobotsky, J. H., H. I. Wyss, E. J. Segre, and C. W. LloydJ Clin Endocritiol Metab 24: 1261, 1964. 5. Judd, H. L., and S. S. C. Yen, J Clin Endocrinol Metab 36: 475, 1973. 6. Dupon, C , A. Hosseinian, and M. H. Kim, Steroids 22: 47, 1973.
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