Daily blood hormone levels related to the luteinizing hormone surge in anovulatory cycles

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1 FRTILITY AND STRILITY Copyright 1983 The American Fertility Society Printed in U.8A. Daily blood hormone levels related to the luteinizing hormone surge in anovulatory cycles Chung H. Wu, M.D. * F. Susan Cowchock, M.D.t Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania We have evaluated daily blood levels of gonadal steroids and trophic hormones in the cycles of four ovulatory and six anovulatory patients with a luteinizing hormone (LH) surge. The cycles of anovulatory nonhirsute patients were characterized by a premature and blunted LH surge and by low levels of follicle-stimulating hormone (FSH) throughout the study period in the face of normal tonic and peak levels of estrone and estradiol (:J. These observations, together with decreased levels of prolactin, suggest a hypothalamic pituitary abnormality as the cause of anovulation in these patients. The cycles of anovulatory hirsute patients were marked by a decrease in 2 production and a blunted and delayed 2 peak. Androgen levels were elevated throughout the cycle and may have a direct inhibitory effect on ovarian folliculogenesis. The LHIFSH ratio in the follicular phase was high in both groups of anovulatory patients when compared with ovulatory controls; however, the shifts in gonadotropin levels producing the increase in this ratio were different for these two groups. Fertil Steril 39:39, 1983 In the normal menstrual cycle the preovulatory estradiol (2) rise feeds back to the hypothalamicpituitary axis to trigger a luteinizing hormone (LH) surge. The midcycle LH surge triggers a series of biochemical reactions that lead to follicular rupture and expulsion of the ovum. 1 Other pituitary hormones, prolactin (PRL) and folliclestimulating hormone (FSH), are also released at this time,2 but their role in ovulatory events is uncertain. In addition to the well-known patterns of 2 and progesterone (P) at ovulation, midcycle elevations of androstenedione (A) and testoster- one (T) have been described,3 although other reports 4 have disagreed with this observation. In the anovulatory cycles of patients who are not amenorrheic, there is evidence of follicular activity with a rise in 2 levels prior to menstruation.5 In these cycles an LH surge may follow the rise in 2 level, but ovulation does not occur.5 In order to investigate this form of ovulatory failure, we have measured and compared daily plasma levels of LH, FSH, PRL, estrone ( 1), 2, A, T, and P in ovulatory and anovulatory cycles with an LH surge. Received August 16, 1982; accepted September 14, *Reprint requests: Chung H. Wu, M.D., Department ofobstetrics and Gynecology, Jefferson Medical College, 1025 Walnut Street, Philadelphia, Pennsylvania tdepartment of Medicine. MATRIALS AND MTHODS Daily blood samples were obtained between 8:00 A.M. and 10:00 A.M. from four patients with normal ovulatory cycles and from six oligomenorrheic patients during anovulatory cycles. The plasma samples were separated and stored at Wu and Cowchock Daily hormones in anovulatory cycles 39

2 ... ~ LH 68 Ov(+) Ov(-),H H tr---l> OvH,H(+) ~... RSULTS The patients were grouped as follows: (1) the normal ovulatory group (Ov +); (2) the anovulatory nonhirsute group (Ov -, H -); and (3) the anovulatory hirsute group (Ov -, H +). Daily plasma hormone levels were synchronized on the day of the LH peak as day 0, and the mean daily values of hormones from each group were graphed as shown in Figures 1 to 3. In addition, mean values for all daily hormone levels in the follicular and luteal phases were calculated for each group and are presented in Table 1. ~ Ov(+) 0--0 Ov H, H(-) ~ OV(-),H(+) ~ 20 '" c: " co Q DAY OF CYCL Figure 1 Daily (mean ± standard error [S]) LH, FSH and PRL levels in the periovulatory phase (day -7 to day + 7) of the normal ovulatory (Ov+) cycles and the anovulatory (Ov-) cycles with (H + ) or without (H - ) hirsutism. *p < 0.05 when compared with the ovulatory (Ov+) cycles. 1 _ 20 C until assayed by radioimmunoassays as previously reported ach patient's samples were assayed in one batch to minimize interassay error. The date of LH peak in each cycle was designated day 0, and the periovulatory period analyzed extended from day - 7 to day + 7 according to this reference point. The difference between mean values was evaluated by Student's t-test. All patients had a body weight within ± 15% of ideal and were between 19 and 27 years of age. Routine endocrine tests including thyroid and adrenal function were normal in all patients. However, three of the anovulatory subjects had hirsutism and elevated serum T levels, whereas the other three were normal in these respects. 40 Wu and Cowchock Daily hormones in anovulatory cycles 100 " co Q o DAY OF CYCL Figure 2 Daily (mean ± S) plasma 2 and l levels in the periovulatory phase (day - 7 to day + 7) of the normal ovulatory (Ov + ) cycles and the anovulatory (Ov - ) cycles with (H + ) or without (H - ) hirsutism. *p < 0.05 when compared with the ovulatory (Ov+) cycles. Fertility and Sterility

3 hormone is thought to be of critical importance in follicular development. 12, 13 In addition to the elevated mean LH noted prior to the LH surge in the Ov -, H + group, FSH values were the same as those in Ov + control subjects prior to the LH surge and lower than control subjects after the surge. LH levels were normal prior to the LH surge in the Ov -, H - group, but FSH levels were consistently low. The midcycle FSH peak was also absent in this latter group. STRADIOL AND STRON (FIG. 2) " at Q. " at C 1000 T DAY OF CYCL Figure 3 Daily (mean ± S) plasma P, T, and A levels in the periovulatory phase (day -7 to day +7) of the normal ovulatory (Ov+) cycles and the anovulatory (Ov - ) cycles with (H + ) or without (H - ) hirsutism. *p < 0.05 when compared with the ovulatory (Ov + ) cycles. LUTINIZING HORMON (FIG. 1) The Ov -, H + group had elevated levels of LH in the late follicular phase (day -7 to day -1) when compared with Ov + control subjects and the Ov -, H - group (P < 0.05). The mean value for the subsequent LH surge in this group was not different from that of normal control subjects. The Ov -, H - group, in contrast, had a significantly lower mean value for the LH surge (P < 0.05). FOLUCL-STIMULATING HORMON (FIG. 1) The measurement of FSH values was extended to include the entire follicular phase because this In the normal ovulatory cycles, the 2 level rose rapidly after day - 3 and peaked on day - 1. Following ovulation the levels declined precipitously to baseline levels by day + 1 and gradually rose in the early luteal phase. In both groups of anovulatory patients, the 2 peak was delayed by 1 day, i.e., 2 levels peaked on day 0 rather than day -1. The mean value for 2 levels was significantly lower (P < 0.05) for the Ov -, H + group throughout the study period (Table 1), and the 2 peak was markedly blunted. Normal tonic 2 levels, followed by an adequate (although delayed) 2 peak, were found in the Ov -, H - group, although this stimulus did not result in a normal LH surge. The pattern of 1 production was not different between the groups, except that (1) the peak was delayed to day + 1 in the Ov -, H patients, and (2) 1 levels were significantly low (P < 0.05) on day +6 and day +7 of the Ov-, H+ group. PROGSTRON (FIG. 3) P levels rose rapidly after day + 1 and reached 14 to 20 ng/ml on day + 7 of the normal cycles. P levels were significantly elevated (P < 0.05) prior to the LH surge only in the Ov -, H - group. In all anovulatory cycles P peaked on day + 1 or day + 2 at 3 ng/ml and then declined to baseline levels. Menstrual bleeding in the anovulatory patients occurred between day + 4 and day + 6 and lasted 4 to 5 days. In this sense these "anovulatory" patients might be considered as an extreme failure of adequate luteinization. The absence of ovum expulsion from the follicle cannot be documented by the techniques used in this study. PROLACTIN (FIG. 1) PRL levels were elevated in both the Ov + and Ov -, H + groups at midcycle on day -1 and day Wu and Cowchock Daily hormones in anovulatory cycles 41

4 Table 1. Mean (± Standard rror) Daily Plasma Hormone Levels During the Period of Pre-LH (Day - 7 to Day -1) and Post-LH (Day + 1 to Day + 7) Peak in the Ovulatory and the Anovulatory Cycles Anovulatory cycles Ovulatory cycles Without hirsutism With hirsutism Hormone Pre-LH peak Post-LH peak Pre-LH peak Post-LH peak Pre-LH peak Post-LH peak LH (miu/ml) FSH (miu/ml) LHIFSH ratio Prolactin (ng/ml) stradiol (pg/ml) strone (pg/ml) Progesterone (ng/ml) Testosterone (pg/ml) Androstenedione (ng/ml) 4 cycles, n = ± ± ± ± ± ± ± ± ± 15c 84 ± ± ± ± 0.10c 10.1 ± ± 36e 338 ± ± ± cycles, n = 21 3 cycles, n = 21 ap < 0.05 when compared with the respective value of ovulatory cycles. bp < 0.05 when compared with the respective value of anovulatory cycles without hirsutism. cp < 0.05 when compared with the respective post-lh peak value. O. PRL levels were uniformly low without a midcycle elevation on the Ov -, H - group. In contrast, Ov -, H + patients had PRL levels similar to Ov + control subjects. ANDROSTNDION AND TSTOSTRON (FIG. 3) T levels fluctuated randomly without a midcycle elevation in the ovulatory and anovulatory patients. As expected, the Ov -, H + patients had higher levels, although the daily mean levels were not significantly different from those of control subjects. The total mean value for the study period, however, was significantly elevated (Table 1). Androstenedione levels were also higher in this group and lacked any midcycle elevation. MAN VALUS OF SUMMD DAILY HORMON AVRAGS In order to estimate total hormone production in each group over the study periods, an average of all daily hormone values for each group was calculated for the late follicular phase (day -7 to day -1) and for the early luteal phase (day + 1 to day + 7) (Table 1). In this table we note again that Ov -, H - patients had normal LH production prior to the surge, but lower levels in the early luteal phase compared with Ov + control subjects. FSH levels were consistently lower than normal in these patients. These changes produced an increase in the LH/FSH ratio in both phases of the menstrual cycle. A similar shift in the LHI FSH ratio was observed only in the follicular phase of Ov -, H + patients. The observed increase in LHIFSH in hirsute patients has also 42 Wu and Cowchock Daily hormones in anovulatory cycles 7.2 ± 0.89c 4.2 ± 0.64a 13.4 ± 1.2a,b,c 5.0 ± ± 0.18a 1.5 ± 0.15a 5.5 ± 0.78b,c 2.4 ± 0.41 a,b 5.65 ± 0.82a,c 2.91 ± 0.51a 4.43 ± 0.88a,c 1.78 ± 0.20b 1.2 ± O.la 2.3 ± 0.6a 17.3 ± 2.6b 20.2 ± 2.7b 100 ± ± ± 13a,c 36 ± 6.4a,b 68 ± ± ± ± ± O.l1a 1.70 ± 0.18a 0.98 ± 0.13b,c 1.43 ± 0.17a 257 ± 26a 289 ± ± 53a,b 6 ± a,b 1.02 ± ± ± 0.18a,b 1.60 ± O.17a,b been noted by others to result from the increased level of LH that exists prior to the surge, together with normal levels of FSH. The remarkably low mean values for PRL in Ov -, H - patients and for 2 in Ov -, H + patients have already been mentioned. Again, significantly elevated levels of the androgens (T and A) were found in hirsute (Ov-, H + ) patients. An elevated level of P prior to the surge in Ov -, H - patients was a surprising observation. DISCUSSION ANOVULATORY, NONHIRSUT PATINTS (Ov-, H-) Although 2 peak levels were normal in these cycles, the LH surge initiated was premature and blunted. This observation suggests an abnormality in the positive feedback of 2 to the hypothalamic-pituitary area for LH release. One might postulate that an increased sensitivity to rising 2 at the level of the hypothalamus could stimulate gonadotropin-releasing hormone before 2 levels have adequately primed the pituitary with stores of readily releasable LH. In addition, the low FSH level present in the follicular phase might also represent an increase in the sensitivity of the negative feedback system. These low levels of FSH probably contribute to poor follicle development. Similar studies in patients with a less exaggerated luteal phase defect have suggested that the rising FSH levels in the early follicular phase are crucial for normal follicle development.12, 13 The low PRL levels observed in this group also suggest a hypothalamic-pituitary Fertility and Sterility

5 abnormality. PRL may be significant in normal ovulation, or the release of PRL may be a secondary consequence of estrogen priming of the pituitary. PRL has been reported to influence the P secretion in the ovarian follicles. 14 Hypoprolactinemia may reduce ovarian response to gonadotropin and, together with low levels of FSH, further impair follicular maturation. P levels were elevated prior to the LH surge in these patients. A slightly elevated P level in the follicular phase of anovulatory cycles seems to be common, but the biologic consequences ofthis early rise are not clear. It is possible that a tonically elevated P level in the follicular phase could suppress gonadotropin release and lead to further abnormality in follicle maturation. ANOVULATORY HIRSUT PATINTS (Ov-, H+) The elevated androgen levels, both A and T, in this group may have a direct inhibitory effect on ovarian folliculogenesis. In spite of adequate FSH and PRL secretion in the follicular phase of these cycles, 2 production is markedly decreased, and the 2 peak is blunted as well as delayed. The relatively high levels oflh in the follicular phase of these patients has been explained by inappropriate feedback at the level of the hypothalamus. 15 This increased LH release without adequate FSH may stimulate further secretion of ovarian androgens and lead to cumulative abnormalities in follicle development. The high levels of androgens may add to the positive feedback of relatively low peak estrogen levels, to produce an apparently normal but premature LH surge at midcycle. In these "anovulatory" patients follicular activity was noted in the study cycle and followed by an LH surge. The LH surge initiated a brief spurt of P production. Since these patients have simultaneous withdrawal of 2 and P, their menses tend to be normal in duration. Oligomenorrheic patients who lack this brief period ofp production may have prolonged menstrual bleeding with incomplete endometrial shedding. RFRNCS 1. Yen SSC: The human menstrual cycle: integrative function of the hypothalamic-pituitary-ovarian-endometrial axis. In Reproduction ndocrinology, Physiology, Pathophysiology and Clinical Management, dited by SSC Yen, RB Jaffe. Philadelphia, W. B. Saunders Co., 1978, p Vekemans M, Delvoye P, L'Hermite M, Robyn C: Serum prolactin levels during the menstrual cycle. J Clin ndocrinol Metab 44:989, Judd HL, Yen SSC: Serum androstenedione and testosterone levels during the menstrual cycle. J Clin ndocrinol Metab 36:475, Wu CH: Monitoring of ovulation induction. Fertil Steril 30:617, Wu CH, Mikhail G: Plasma hormone profile in anovulation. Fertil Steril 31:258, Midgley AR: Radioimmunoassay for human follicle-stimulating hormone. J Clin ndocrinol Metab 27:295, Midgley AR: Radioimmunoassay: a method for human chorionic gonadotropin and human luteinizing hormone. ndocrinology 79:10, Wu CH: Radioimmunoassay of plasma estrogens. Steroids 18:91, DeVilla GO Jr, Roberts K, Wiest WG, Mikhail G, Flickinger G: A specific radioimmunoassay of plasma progesterone. J Clin ndocrinol Metab 35:458, Wu CH, Blasco L, Flickinger GL, Mikhail G: Ovarian function in the preovulatory rabbit. BioI Reprod 17:304, Sinha YN, Selby FW, Lewis UJ, Vanderlaan WP: A homologous radioimmunoassay for human prolactin. J Clin ndocrinol Metab 36:9, Sherman BM, Korenman SG: Measurement of serum LH, FSH, estradiol and progesterone in disorders of the human menstrual cycle: inadequate luteal phase. J Clin ndocrinol Metab 39:145, dizerega G, Hodgen GD: Luteal phase dysfunction infertility: a sequel to aberrant folliculogenesis. Fertil Steril 35:489, McNatty KP, Sawers RS, McNeilly AS: A possible role for prolactin in control of steroid secretion by the human Graafian follicles. Nature 2:653, Yen SSC: Chronic anovulation due to inappropriate feedback system. In Reproductive ndocrinology, Physiology, Pathophysiology and Clinical Management, dited by SSC Yen, RB Jaffe. Philadelphia, W. B. Saunders Co., 1978, p 297 Wu and Cowchock Daily hormones in anovulatory cycles 43