Effect of oral administration of a continuous 18 day regimen of meloxicam on ovulation: experience of a randomized controlled trial.

BACKGROUND: Cyclooxygenase-2 (COX-2) is expressed in all female reproductive organs. Therefore, inhibitors of COX-2 may affect reproductive function. We evaluated the effect of extended administration of meloxicam on ovulation and the menstrual cycle. Our hypothesis was that meloxicam administered from menstrual cycle day 5- 22 could interfere with follicular rupture, without disrupting the menstrual cycle, and could be a potential non-hormonal contraceptive method. METHODS: The study was conducted in 56 healthy sterilized women. Before the onset of treatment and after the end of treatment, participants were observed during a control cycle to ensure that they had progesterone (P4) serum levels (>12 nmol/l) consistent with ovulation. Participants were treated for 18 days, during three consecutive cycles. They were randomized to 15 or 30 mg/day. The menstrual cycle was monitored with serial ultrasound and hormone assays in blood. RESULTS: Fifty-six volunteers completed the study. In 55% of cycles treated with 15 mg/day and in 78% of cycles treated with 30 mg/day (p<0.001) we observed dysfunctional ovulation defined as follicular rupture not preceded 24-48 h earlier by an LH peak or preceded by a blunted LH peak (<21 IU/l) or not followed by an elevated serum P4 level >12 nmol/l. Ovulation was observed in 44.6% and in 21.7% of women in the lower dose group and the higher dose group, respectively. There were no differences between the two doses in other parameters measured. There were no serious adverse events and adverse events were not different between doses or between control and treated cycles. CONCLUSIONS: Although administration of meloxicam on menstrual cycle days 5- 22 resulted in a dose-dependent inhibition of ovulation, more than 20% of subjects had normal ovulation with the highest dose. IMPLICATIONS: Previous studies have shown that oral meloxicam can delay follicle rupture. This study investigated daily oral meloxicam as a non-hormonal contraceptive. Since ovulation occurs in over 20% of cycles even with a high dose of 30 mg daily, it is not likely that the approach would be a highly effective contraceptive strategy.

Effect of single post-ovulatory administration of levonorgestrel on gene expression profile during the receptive period of the human endometrium.

The hypothesis that levonorgestrel (LNG) used as an emergency contraceptive interferes with endometrial receptivity remains unproven. We compared the endometrial gene expression profile during the receptive period after administering a single dose of LNG 1.5 mg or placebo on day 1 of the luteal phase. An endometrial biopsy was done on day LH+7 or LH+8 and samples were taken from seven volunteers, each one contributing with one cycle treated with placebo and another with LNG. The expression of 20 383 genes was determined using cDNA microarrays. Real-time RT-PCR was used 1) to confirm the differences found in DNA microarray analysis and 2) to determine the effect of LNG on transcript levels of C3, C4BPα, COX2, MAOA, S100A4, and SERPINB9, known to be upregulated during receptivity, and on cPLA2α, JAK1, JNK1, CTSL1, and GSTP1, known to respond to mifepristone. Additional endometrial biopsies were done during the pre-receptive (LH+3) and receptive (LH+7) period and samples were taken from eight untreated volunteers in order to determine the changes associated with acquisition of receptivity of 14 genes. Mean levels of PAEP, TGM2, CLU, IGF2, and IL6ST mRNAs increased after administering LNG while those of HGD, SAT1, EVA1, LOC90133, ANXA1, SLC25A29, CYB5A, CRIP1, and SLC39A14 decreased. Except for the level of ANXA1 transcript, all changes remained within the range observed in untreated controls, and none of the transcripts responding to mifepristone changed in response to LNG. Post-ovulatory administration of LNG caused minimal changes in gene expression profiling during the receptive period. Neither the magnitude nor the nature or direction of the changes endorses the hypothesis that LNG interferes with endometrial receptivity.

Endometrial effect of progesterone delivered by vaginal rings in estrogen-treated postmenopausal women.

AIM: The type of estrogen and progestin as well as their doses, route and regimens of administration may each affect the benefit-risk profile of postmenopausal hormone therapy. The aim of this study was to evaluate the endometrial effect of progesterone released continuously from a vaginal ring, combined with transdermal estradiol in postmenopausal women. METHOD: Forty-four postmenopausal women participated in a randomized, double-blind, dose-finding study evaluating two hormonal treatments, combining 50 microg/day of estradiol delivered by transdermal patches and either 0.5-g or 1-g progesterone vaginal rings (PVR) given for 12 weeks. The effect on the endometrium was assessed by histology and the detection of the proliferative marker Ki-67. We also measured the serum concentration of estradiol and progesterone, the tissue concentration of progesterone and the immunolocalization of estradiol and progesterone receptors in the endometrium. RESULTS: Endometrial thickness was increased after both treatments, although endometrial histology appeared atrophic in most biopsies. A circulating dose-response of serum progesterone levels was observed from the first to the 12th week of PVR use. In the high-progesterone-dose group, the scarce presence of Ki-67 and hormone receptors reflected the predominant action of progesterone in endometrial glands and stroma, in parallel with a lower tissue concentration of progesterone in this group. CONCLUSION: The PVR appears to be a promising method of administering natural progesterone to postmenopausal women treated with estrogen. Estradiol levels corrected the menopausal symptoms, as expected, and the presence of atrophic endometrium in the majority of women indicated that both doses of progesterone oppose the stimulatory estradiol effects, although the percentage of proliferative tissue was not negligible in both groups.

Immediate pre-ovulatory administration of 30 mg ulipristal acetate significantly delays follicular rupture.

BACKGROUND: Current methods of hormonal emergency contraception (EC) are ineffective in preventing follicular rupture when administered in the advanced pre-ovulatory phase. This study was designed to determine the capacity of ulipristal acetate (UPA), a selective progesterone receptor modulator developed for EC, to block follicular rupture when administered with a follicle of >or=18 mm. METHODS: This was a double-blind, crossover, randomized, placebo-controlled study. Thirty-five women contributed with UPA (30 mg. oral) and a placebo cycle. Serial blood sampling for luteinizing hormone (LH), estradiol and progesterone measurements and follicular monitoring by ultrasound were performed before and for 5 days following treatment. Follicular rupture inhibition was assessed in the overall study population and in subgroups of women stratified by when treatment was administered in relation to LH levels (before the onset of the LH surge, after the onset of the surge but before the LH peak or after the LH peak). RESULTS: Follicular rupture failed to occur for at least 5 days following UPA administration in 20/34 cycles [59%; 95% confidence interval (CI) (40.7-75.4%)], whereas rupture took place in all cycles within 5 days of placebo intake. When UPA was administered before the onset of the LH surge, or after the onset but before the LH peak, follicle rupture had not occurred within 5 days in 8/8 (100%) and 11/14 [78.6%; 95% CI (49.2-95.3)] cycles, respectively. In contrast, when UPA was given after the LH peak, follicle rupture inhibition was only observed in 1/12 [8.3%; 95% CI (0.2-38.5)] cycles. CONCLUSIONS: This study demonstrates that UPA can significantly delay follicular rupture when given immediately before ovulation. This new generation EC compound could possibly prevent pregnancy when administered in the advanced follicular phase, even if LH levels have already begun to rise, a time when levonorgestrel EC is no longer effective in inhibiting ovulation.

Genital sensory stimulation shifts estradiol intraoviductal signaling from nongenomic to genomic pathways, independently from prolactin surges.

Estradiol (E2) accelerates oviductal egg transport through nongenomic pathways involving oviductal protein phosphorylation in non-mated rats, and through genomic pathways in mated rats. Here we investigated the ability of cervico-vaginal stimulation (CVS) to switch the mode of action of E2 in the absence of other male-associated components. Pro-estrous rats were subjected to CVS with a glass rod and 12 hours later were injected subcutaneously with E2 and intrabursally with the RNA synthesis inhibitor Actinomycin D or the protein phosphorylation inhibitor H-89. The number of eggs in the oviduct, assessed 24 h later, showed that Actinomycin D, but not H-89 blocked the E2-induced egg transport acceleration. This clearly indicates that CVS alone, without other mating-associated signals, is able to shift E2 signaling from nongenomic to genomic pathways. Since mating and CVS activate a neuroendocrine reflex that causes iterative prolactin (PRL) surges, the involvement of PRL pathway in this phenomenon was evaluated. Prolactin receptor mRNA and protein expression in the rat oviduct was demonstrated by RT-PCR and Western blot, but their levels were not different on day 2 of the cycle (C2) or pregnancy (P2). Activated ST AT 5a/b (phosphorylated) was detected by Western blot on P2 in the ovary, but not in the oviduct, showing that mating does not stimulate this PRL signalling pathway in the oviduct. Other rats subjected to CVS in the evening of pro-estrus were treated with bromoergocriptine to suppress PRL surges. In these rats, H-89 did not block the E2-induced acceleration of egg transport suggesting that PRL surges are not essential to shift E2 signaling pathways in the oviduct. We conclude that CVS is one of the components of mating that shifts E2 signaling in the oviduct from nongenomic to genomic pathways, and this effect is independent of PRL surges elicited by mating.

Progesterone, but not luteal estrogen, is required for the establishment of pregnancy in the new world monkey Cebus apella.

The aim of this study was to examine the requirement of luteal progesterone or luteal estrogen for the establishment of pregnancy in the Cebus monkey and to test in a primate species the synergism between RU 486 and letrozole (LTZ) found in rodents for inhibiting implantation. Exposure of target tissues to either hormone was suppressed during the mid-luteal phase of mating cycles by subcutaneous administration of the antiprogestin (RU 486), the aromatase inhibitor LTZ or the antiestrogen (ICI 182780) on days 4-7 of the luteal phase. Administration of 0.1 or 0.5 mg/kg of LTZ on days 5-7 of the luteal phase caused a profound drop in the levels of E(2) in all animals, whereas administration of ICI 182780 0.2 mg/kg on days 4-6 of the luteal phase had the opposite effect. The pregnancy rate in vehicle treated cycles of the same females was (58.3%). Treatment with RU 486, 0.8 mg/kg/day on days 5-7 of the luteal phase-induced endometrial bleeding in 3/5 mated females none of which became pregnant, whereas pregnancy was confirmed in one of the two animals that did not bled. Treatment with RU 486, 0.4 mg/kg/day alone or with LTZ on days 5-7 or ICI 182780 alone, on days 4-6 of the luteal phase failed to induce bleeding, allowing the establishment of pregnancy in 50.0-66.6% of the animals in these groups. We conclude that in Cebus monkeys, progesterone but not luteal estradiol is required for the establishment of pregnancy and that RU 486 and LTZ do not exhibit in this species the synergism found in rodents.

Does meloxicam increase the incidence of anovulation induced by single administration of levonorgestrel in emergency contraception? A pilot study.

BACKGROUND: Levonorgestrel (LNG) consistently prevents follicular rupture only when it is given before the onset of the ovulatory stimulus. As locally synthesized prostaglandin (PG) plays a crucial role in follicular rupture and cyclooxygenase-2 (cox-2) catalyses the final step of PG synthesis, we reasoned that adding a cox-2 inhibitor to LNG would prevent follicular rupture even after the ovulatory process had been triggered by the gonadotrophin surge. METHODS: Forty-one women were divided into two groups. One was treated when the size of the leading follicle was 15-17 mm (n=10) and the other when it was >or=18 mm (n=31). Each woman contributed with one cycle treated with LNG 1.5 mg single dose plus placebo and another treated with LNG + meloxicam (Melox) 15 mg, in a randomized order. Serial blood sampling for the assay of LH and follicular monitoring by transvaginal ultrasound were performed before and after treatment. RESULTS: Follicular rupture failed to occur within the 5-day period that followed treatment in 50 and 70% of cycles treated with LNG + Placebo and LNG + Melox, respectively, in the 15-17 mm group (P=0.15) and in 16 and 39% of cycles treated with LNG + Placebo and LNG + Melox, respectively, in the >or=18 mm group (P < 0.052). The overall proportion of cycles with no follicular rupture or ovulatory dysfunction increased significantly by the addition of Melox to LNG (66 versus 88%, P < 0.012; n=41-matched pairs). CONCLUSIONS: The trend towards increased incidence of no follicular rupture when Melox was combined with LNG suggests that the addition of a cox-2 inhibitor has the potential to improve the contraceptive efficacy of LNG by a pre-fertilization effect.

Genital Sensory Stimulation Shifts Estradiol Intraoviductal Signaling from Nongenomic to Genomic Pathways, Independently from Prolactin Surges

Estradiol (E2) accelerates oviductal egg transport through nongenomic pathways involving oviductal protein phosphorylation in non-mated rats, and through genomic pathways in mated rats. Here we investigated the ability of cervico-vaginal stimulation (CVS) to switch the mode of action of E2 in the absence of other male-associated components. Pro-estrous rats were subjected to CVS with a glass rod and 12 hours later were injected subcutaneously with E2 and intrabursally with the RNA synthesis inhibitor Actinomycin D or the protein phosphorylation inhibitor H-89. The number of eggs in the oviduct, assessed 24 h later, showed that Actinomycin D, but not H-89 blocked the E2-induced egg transport acceleration. This clearly indicates that CVS alone, without other mating-associated signals, is able to shift E2 signaling from nongenomic to genomic pathways. Since mating and CVS activate a neuroendocrine reflex that causes iterative prolactin (PRL) surges, the involvement of PRL pathway in this phenomenon was evaluated. Prolactin receptor mRNA and protein expression in the rat oviduct was demonstrated by RT-PCR and Western blot, but their levels were not different on day 2 of the cycle (C2) or pregnancy (P2). Activated ST AT 5a/b (phosphorylated) was detected by Western blot on P2 in the ovary, but not in the oviduct, showing that mating does not stimulate this PRL signalling pathway in the oviduct. Other rats subjected to CVS in the evening of pro-estrus were treated with bromoergocriptine to suppress PRL surges. In these rats, H-89 did not block the E2-induced acceleration of egg transport suggesting that PRL surges are not essential to shift E2 signaling pathways in the oviduct. We conclude that CVS is one of the components of mating that shifts E2 signaling in the oviduct from nongenomic to genomic pathways, and this effect is independent of PRL surges elicited by mating.

Pituitary-ovarian axis during lactational amenorrhoea. II. Longitudinal assessment of serum FSH polymorphism before and after recovery of menstrual cycles.

BACKGROUND: The association of normal serum levels of immunoassayable gonadotrophins with anovulation during lactational amenorrhoea (LA) has not been fully explained. METHODS: Serum FSH polymorphism was analysed in 10 women during LA between days 60 and 70 post-partum and again, in the mid-follicular phase (MFP), after resuming menstrual cyclicity. FSH microheterogeneity was characterized according to charge, using preparative isoelectric focusing, and according to the inner structure of carbohydrate chains, using lectin chromatography. RESULTS: A significantly higher proportion of FSH charge isoforms isolated below pH 4.10 and a lower proportion of FSH isoforms bearing highly branched oligosaccharides were observed during LA when compared to MFP. Further analysis with higher resolution showed that FSH charge isoforms, isolated in the lower pH range in LA, corresponded to FSH molecules bearing highly branched and biantennary oligosaccharides. FSH isoforms bearing hybrid-type oligosaccharides were only present during LA. The circulating FSH isoform mix was significantly less bioactive in LA than in MFP. LA is characterized by a more acidic mix of FSH isoforms, containing hormone bearing less processed oligosaccharides, with decreased biopotency in comparison with the follicular phase. CONCLUSIONS: This FSH microheterogeneity may be one of the critical factors contributing to incomplete follicular development and anovulation during LA.

Pituitary-ovarian axis during lactational amenorrhoea. I. Longitudinal assessment of follicular growth, gonadotrophins, sex steroids and inhibin levels before and after recovery of menstrual cyclicity.

BACKGROUND: Comparisons of follicular development and hormonal profile in the same women during and after lactational amenorrhoea (LA) are scarce. We report follicular growth, pituitary and ovarian hormone serum levels in the same women during LA and in follicular phases after resumption of menstrual cyclicity. METHODS: Serum samples were obtained from 10 women during LA between days 60 and 89 post-partum and between days 1 and 4 (early follicular phase; EFP) and 7 and 10 (mid-follicular phase; MFP) of the second and third cycles after LA. RESULTS: The number of follicles >3 mm and diameter of the largest follicle were significantly higher during LA when compared to EFP and MFP. Serum levels of inhibin B were similar in LA and EFP and increased significantly in MFP. Pro-alphaC was significantly higher in EFP than in LA and MFP. Estradiol was similar during all stages. In comparison with EFP and MFP, LA is associated with higher prolactin levels, normal or slightly elevated gonadotrophins and increased number and size of follicles without a parallel increase in estradiol, inhibin B and Pro-alphaC. CONCLUSIONS: During LA, there is a profound dissociation between follicular growth and follicular endocrine activity, which suggests an alteration in the stimulus-response relationship at the follicular level.

Cytologic, hormonal, and ultrasonographic correlates of the menstrual cycle of the New World monkey Cebus apella.

Few reports on the reproductive physiology of Cebus apella have been published. In this study we characterized menstrual cycle events by means of vaginal cytology, ultrasonography (US), and hormonal measurements in serum during three consecutive cycles in 10 females, and assessed the probability that ovulation would occur in the same ovary in consecutive cycles in 18 females. The lengths and phases of the cycles were determined according to vaginal cytology. Taking the first day of endometrial bleeding as the first day of the cycle, the mean cycle length +/- SEM was 19.5+/-0.4 days, with follicular and luteal phases lasting 8.2+/-0.2 and 11.3+/-0.4 days, respectively. The follicular phase included menstruation and the periovulatory period, which was characterized by the presence of a large number of superficial eosinophilic cells in the vaginal smear. The myometrium, endometrium, and ovaries were clearly distinguished on US examination. During each menstrual cycle a single follicle was recruited at random from either ovary. The follicle grew from 3 mm to a maximum diameter of 8-9 mm over the course of 8 days, in association with increasing estradiol (E(2)) serum levels (from 489+/-41 to 1600+/-92 pmol/L). At ovulation, the mean diameter of the dominant follicle usually decreased by >20%, 1 day after the maximum E(2) level was reached. Ovulation was associated with an abrupt fall in E(2), a decreased number of eosinophilic cells, the presence of leukocytes and intermediate cells in the vaginal smear, and a progressive increase in progesterone (P) levels that reached a maximum of 892+/-65 nmol/L on days 3-6 of the luteal phase. The menstrual cycle of Cebus apella differs in several temporal and quantitative aspects from that in humans and Old World primates, but it exhibits the same correlations between ovarian endocrine and morphologic parameters.

Pituitary-ovarian function following the standard levonorgestrel emergency contraceptive dose or a single 0.75-mg dose given on the days preceding ovulation.

We assessed to what extent the standard dose of levonorgestrel (LNG), used for emergency contraception, or a single dose (half dose), given in the follicular phase, affects the ovulatory process during the ensuing 5-day period. Fifty-eight women were divided into three groups according to timing of treatment. Each woman contributed with three treatment cycles separated by resting cycles. All received placebo in one cycle, and standard or single dose in two other cycles, in a randomized order. The diameter of the dominant follicle determined the time of treatment. Each woman had the same diameter assigned for all her treatments. Diameters were grouped into 33 categories: 12-14, 15-17 or 18-20 mm. Follicular rupture failed to occur during the 5-day period in 44%, 50% and 36% of cycles with the standard, half dose and placebo, respectively. Ovulatory dysfunction, characterized by follicular rupture associated with absent, blunted or mistimed gonadotropin surge, occurred in 35%, 36% and 5% of standard, single dose or placebo cycles, respectively. In conclusion, LNG can disrupt the ovulatory process in 93% of cycles treated when the diameter of the dominant follicle is between 12 and 17 mm. It is highly probable that this mode of action fully accounts for the contraceptive efficacy as well as the failure rate of this method. The present data suggest that half the dose may be as effective as the standard dose.

Post-coital administration of levonorgestrel does not interfere with post-fertilization events in the new-world monkey Cebus apella.

BACKGROUND: Experimental evidence to disprove the belief that emergency contraception with levonorgestrel (LNG) prevents pregnancy by interfering with post-fertilization events is lacking. Here we determined the effect of post-coital and pre-ovulatory administration of LNG on fertility and ovulation, respectively, in the Cebus monkey. METHODS: To determine the effect on fertility, LNG 0.75 mg or vehicle were administered orally or s.c. once or twice within the first 24 h after mating occurring very close to the time of ovulation. Females that became pregnant were aborted with mifepristone and re-entered the study after a resting cycle until each of 12 females had contributed, in a randomized order, two LNG and two vehicle-treated cycles. To determine the effect on ovulation, LNG 0.75 mg or vehicle were injected twice coinciding with follicles smaller or larger than 5 mm in diameter. Six females contributed five treated cycles each. RESULTS: The pregnancy rate was identical in vehicle- and LNG-treated cycles. LNG inhibited or delayed ovulation only when treatment coincided with a follicle <5 mm diameter. CONCLUSION: In Cebus monkeys, LNG can inhibit or delay ovulation but, once fertilization has taken place, it cannot prevent the establishment of pregnancy. These findings do not support the hypothesis that emergency contraception with LNG prevents pregnancy by interfering with post-fertilization events.

Postcoital treatment with levonorgestrel does not disrupt postfertilization events in the rat.

Levonorgestrel (LNG), a progestin widely used for regular hormonal contraception, is also used for emergency contraception (EC) to prevent pregnancy after unprotected intercourse. However, its mode of action in EC is only partially understood. One unresolved question is whether or not EC prevents pregnancy by interfering with postfertilization events. Here, we report the effects of acute treatment with LNG upon ovulation, fertilization and implantation in the rat. LNG inhibited ovulation totally or partially, depending on the timing of treatment and/or total dose administered, whereas it had no effect on fertilization or implantation when it was administered shortly before or after mating, or before implantation. It is concluded that acute postcoital administration of LNG at doses several-fold higher than those used for EC in women, which are able to inhibit ovulation, had no postfertilization effect that impairs fertility in the rat.

Effect of intrauterine insemination with spermatozoa or foreign protein on the mechanism of action of oestradiol in the rat oviduct.

Previously, we showed that oestradiol accelerates oviductal egg transport through a non-genomic action involving oviductal protein phosphorylation in non-mated rats, and through a genomic action in mated rats. Thus, sensory stimulation, seminal fluid or sperm cells may be the source of signals that switch the mechanism of action of oestradiol in the oviduct to a genomic pathway. The present study examined the ability of spermatozoa to switch the mode of action of oestradiol in the absence of the sensory stimulation and seminal fluid provided by mating. Pro-oestrous rats were inseminated in each uterine horn with epididymal spermatozoa and 12 h later were injected subcutaneously with oestradiol and intrabursally with the mRNA synthesis inhibitor alpha-amanitin. The number of eggs in the oviduct, assessed 24 h later, showed that alpha-amanitin blocked the oestradiol-induced egg transport acceleration, indicating that the interaction of spermatozoa with the genital tract shifts the action of oestradiol from non-genomic to genomic. Other rats were inseminated with live or dead spermatozoa and then treated with the protein kinase inhibitor H-89, and oestradiol. Treatment with H-89 did not block the oestradiol-induced acceleration of egg transport in these rats, although dead spermatozoa did not enter the oviduct, indicating that the mere presence of spermatozoa in the uterus abrogated the non-genomic action of oestradiol in the oviduct. Treatment with H-89 also failed to prevent the acceleration of oviductal egg transport induced by oestradiol in rats inseminated with hamster spermatozoa or with BSA, whereas in rats inseminated with their own serum (autologous proteins), H-89 was able to prevent the effect of oestradiol. This finding reveals that the effect of insemination on the mode of action of oestradiol is neither species-nor sperm-specific and it is produced by foreign organic material. It can be concluded that the presence of spermatozoa or foreign protein in the uterus is one of the components of mating that is capable of switching the action of oestradiol in the oviduct from a non-genomic to a genomic mode.

Improving cycle control in progestogen-only contraceptive pill users by intermittent treatment with a new anti-progestogen.

BACKGROUND: The safety and efficacy of the anti-progestogen Org 31710 in improving cycle control in healthy women using the desogestrel progestogen-only pill was investigated in this randomized, double-blind, placebo-controlled study. METHODS: A total of 103 women using the 75 micro g desogestrel progestogen-only pill daily also received either 150 mg Org 31710 or placebo once every 28 days, starting on day 1, for a duration of 4-7 treatment cycles. RESULTS: The percentage of women with bleeding or spotting (B/S) every day in the placebo group was on average 30% during the whole treatment period and no days without reported B/S occurred. In contrast, a cyclic pattern was observed for the Org 31710 group; a peak incidence of B/S was observed on day 3 or 4 of each cycle, followed by a sharp decrease on cycle days 9-15. Compared with controls, less subjects in the Org 31710 group reported irregular, frequent or prolonged bleeding. These differences were clearly observed in the initial cycles, but were somewhat less pronounced during the later cycles of the treatment period. A relatively high incidence of B/S episodes starting in the second section of the cycle was also observed. CONCLUSION: The addition of Org 31710 once a month improved cycle control in women using daily treatment with 75 micro g desogestrel.

Effects of the Yuzpe regimen, given during the follicular phase, on ovarian function.

This study was conducted to assess to what extent the Yuzpe regimen, or half the dose, given in the follicular phase, prevents ovulation during the ensuing 5 days. Sixty women were divided into six groups. All groups received placebo in one cycle and drug in another, in a randomized order. Groups differed by the dose and size of the leading follicle at the time of treatment (12-14, 15-17, or 18-20 mm). Ovulation was absent during the ensuing 5 days in 13 of 20 participants (65%) and in 8 of 20 participants (40%) who received the full and the half dose, respectively, when follicles were 12-17 mm. No ovulation occurred, within the critical period, in 7 of 39 placebo cycles (18%). When follicles were 18-20 mm, treatment did not prevent ovulation. In most drug-treated cycles, plasma gonadotropin and sex steroid levels were significantly depressed within the 5-day period, even when follicular rupture occurred within that period. In conclusion, the Yuzpe regimen can suppress or postpone ovulation to an extent that exceeds the fertile life of spermatozoa. Lack of ovulation within the critical period and dysfunction of the ovulatory process probably account for the contraceptive effect of this method in most cases. The present data do not warrant the use of half the dose of the Yuzpe regimen.

Disparate effects of estradiol on egg transport and oviductal protein synthesis in mated and cyclic rats.

Previously, we found that the dose of estradiol (E2) required to accelerate egg transport increases 5- to 10-fold, in mated compared to cyclic rats. Here we examined protein synthesis in the oviduct of mated and cyclic rats following a single injection of E2 known to accelerate oviductal egg transport or after concomitant treatment with progesterone (P4) known to block this acceleration. On Day 1 of the cycle or pregnancy, E2, P4, or E2 + P4 were injected s.c., and 4 h later oviducts were removed and incubated for 8 h in medium with 35S-methionine. Tissue proteins were separated by SDS-PAGE, and protein bands were quantitated by fluorography and densitometry. In mated rats, E2 and P4 increased different protein bands and P4 did not affect the fluorographic pattern induced by E2. In contrast with mated rats, none of these treatments changed the fluorographic pattern of the oviductal proteins in cyclic rats. Estradiol-induced egg transport acceleration was then compared under conditions in which oviductal protein synthesis was suppressed. Mated and cyclic rats treated with equipotent doses of E2 for accelerating egg transport also received actinomycin D (Act D) locally. Estradiol-induced oviductal egg loss was partially blocked by Act D in mated but had no effect in cyclic rats. We conclude that the oviduct of mated and cyclic rats differs in that only the former responds with increased protein synthesis to a pulse of exogenous E2 and P4 and requires an intact protein synthesis machinery in order to accelerate egg transport in response to E2.

Acceleration of oviductal transport of oocytes induced by estradiol in cycling rats is mediated by nongenomic stimulation of protein phosphorylation in the oviduct.

In order to explore nongenomic actions of estradiol (E2) and progesterone (P4) in the oviduct, we determined the effect of E2 and P4 on oviductal protein phosphorylation. Rats on Day 1 of the cycle (C1) or pregnancy (P1) were treated with E2, P4, or E2 + P4, and 0.5 h or 2.5 h later their oviducts were incubated in medium with 32P-orthophosphate for 2 h. Oviducts were homogenized and proteins were separated by SDS-PAGE. Following autoradiography, protein bands were quantitated by densitometry. The phosphorylation of some proteins was increased by hormonal treatments, exhibiting steroid specificity and different individual time courses. Possible mediation of the E2 effect by mRNA synthesis or protein kinases A (PK-A) or C (PK-C) was then examined. Rats on C1 treated with E2 also received an intrabursal (i.b.) injection of alpha-amanitin (Am), or the PK inhibitors H-89 or GF 109203X, and 0.5 h later their oviducts were incubated as above plus the corresponding inhibitors in the medium. Increased incorporation of 32P into total oviductal protein induced by E2 was unchanged by Am, whereas it was completely suppressed by PK inhibitors. Local administration of H-89 was utilized to determine whether or not E2-induced egg transport acceleration requires protein phosphorylation. Rats on C1 or P1 were treated with E2 s.c. and H-89 i.b. The number and distribution of eggs in the genital tract assessed 24 h later showed that H-89 blocked the E2-induced oviductal egg loss in cyclic rats and had no effect in mated rats. It is concluded that E2 and P4 change the pattern of oviductal protein phosphorylation. Estradiol increases oviductal protein phosphorylation in cyclic rats due to a nongenomic action mediated by PK-A and PK-C. In the absence of mating, this action is essential for its oviductal transport accelerating effect. Mating changes the mechanism of action of E2 in the oviduct by waiving this nongenomic action as a requirement for E2-induced embryo transport acceleration.