The luteinized unruptured follicle and other ovulatory dysfunctions

Luteinised unruptured follicle syndrome: pathophysiological background and new target therapy in assisted reproductive treatments

Luteinised unruptured follicle syndrome (LUFS) is a cause of infertility consisting in the unruptured of the dominant follicle after the LH-surge. In fact, during assisted reproductive treatments (ART) clomiphene citrate and letrozole are frequently administered in order to achieve ovulation. However, considering the pathophysiology of LUFS, new possible therapy can be proposed. On this scenario, we performed a review of the literature searching for LUFS recurrency and its impact in infertility and ART. An inflammation theory has been proposed that can be fuel for further therapeutic possibilities. In particular, considering the increase in granulocytes accumulation, the granulocyte colony-stimulating factor (G-CSF) administration has been proposed as target therapy in IUI cycles hampered by LUFS. Although data are encouraging, randomised controlled trials are needed in order to confirm the efficacy of G-CSF administration for LUFS patients.

The Mare: A Pertinent Model for Human Assisted Reproductive Technologies?

Although there are large differences between horses and humans for reproductive anatomy, follicular dynamics, mono-ovulation, and embryo development kinetics until the blastocyst stage are similar. In contrast to humans, however, horses are seasonal animals and do not have a menstrual cycle. Moreover, horse implantation takes place 30 days later than in humans. In terms of artificial reproduction techniques (ART), oocytes are generally matured in vitro in horses because ovarian stimulation remains inefficient. This allows the collection of oocytes without hormonal treatments. In humans, in vivo matured oocytes are collected after ovarian stimulation. Subsequently, only intra-cytoplasmic sperm injection (ICSI) is performed in horses to produce embryos, whereas both in vitro fertilization and ICSI are applied in humans. Embryos are transferred only as blastocysts in horses. In contrast, four cells to blastocyst stage embryos are transferred in humans. Embryo and oocyte cryopreservation has been mastered in humans, but not completely in horses. Finally, both species share infertility concerns due to ageing and obesity. Thus, reciprocal knowledge could be gained through the comparative study of ART and infertility treatments both in woman and mare, even though the horse could not be used as a single model for human ART.

Systematic Review of Ovarian Activity and Potential for Embryo Formation and Loss during the Use of Hormonal Contraception

The purpose of this review was to determine whether there is evidence that ovulation can occur in women using hormonal contraceptives and whether these drugs might inhibit implantation. We performed a systematic review of the published English-language literature from 1990 to the present which included studies on the hormonal milieu following egg release in women using any hormonal contraceptive method. High circulating estrogens and progestins in the follicular phase appear to induce dysfunctional ovulation, where follicular rupture occurs but is followed by low or absent corpus luteum production of progesterone. Hoogland scoring of ovulatory activity may inadvertently obscure the reality of ovum release by limiting the term "ovulation" to those instances where follicular rupture is followed by production of a threshold level of luteal progesterone, sufficient to sustain fertilization, implantation, and the end point of a positive β-human chorionic gonadotropin. However, follicular ruptures and egg release with subsequent low progesterone output have been documented in women using hormonal contraception. In the absence of specific ovulation and fertilization markers, follicular rupture should be considered the best marker for egg release and potential fertilization. Women using hormonal contraceptives may produce more eggs than previously described by established criteria; moreover, suboptimal luteal progesterone production may be more likely than previously acknowledged, which may contribute to embryo loss. This information should be included in informed consent for women who are considering the use of hormonal contraception.

Summary

For this study, the authors looked at English-language research articles that focused on how hormonal birth control, such as the birth control pill, may affect very early human embryos. The authors found that abnormal ovulation, or release of an egg followed by abnormal hormone levels, may often occur in women using hormonal birth control. This may increase the number of very early human embryos who are lost before a pregnancy test becomes positive. For women who are thinking about using hormonal birth control, this is important information to consider.

Granulocyte colony-stimulating factor as a potential inducer of ovulation in infertile women with luteinized unruptured follicle syndrome

Luteinized unruptured follicle (LUF) syndrome is one of the intractable ovulation disorders that are commonly observed during cycles of treatment with ovulation inducers, for which no effective therapy other than assisted reproductive technology is available. Here, we investigated whether granulocyte colony-stimulating factor (G-CSF) could prevent the onset of LUF syndrome. We analyzed the effects of G-CSF in 68 infertile women with LUF syndrome who received ovulation induction (clomiphene + human chorionic gonadotropin [hCG] therapy or follicle-stimulating hormone + hCG therapy). G-CSF (lenograstim, 100 μg) was administered subcutaneously. Onsets of LUF syndrome were compared between the cycle during which G-CSF was given in combination with the ovulation inducer (ie, the G-CSF treatment cycle) and the subsequent cycle during which only the ovulation inducer was given (ie, the G-CSF nontreatment control cycle). The results showed that LUF syndrome recurred in only 3 cycles during the G-CSF treatment cycle (4.4% [3/68 cycles]), whereas LUF syndrome recurred in 13 cycles during the subsequent G-CSF nontreatment control cycle (19.1% [13/68 cycles]). The additional use of G-CSF significantly prevented the onset of LUF syndrome during ovulation induction (P = 0.013, McNemar test). No serious adverse reactions because of the administration of G-CSF were observed. In conclusion, our findings indicate that G-CSF may become a useful therapy for LUF syndrome.

The mare as a model for luteinized unruptured follicle syndrome: intrafollicular endocrine milieu

Luteinized unruptured follicle (LUF) syndrome is a recurrent anovulatory dysfunction that affects up to 23% of women with normal menstrual cycles and up to 73% with endometriosis. Mechanisms underlying the development of LUF syndrome in mares were studied to provide a potential model for human anovulation. The effect of extended increase in circulating LH achieved by administration of recombinant equine LH (reLH) or a short surge of LH and decrease in progesterone induced by prostaglandin F2α (PGF2α) on LUF formation (Experiment 1), identification of an optimal dose of COX-2 inhibitor (flunixin meglumine, FM; to block the effect of prostaglandins) for inducing LUFs (Experiment 2), and evaluation of intrafollicular endocrine milieu in LUFs (Experiment 3) were investigated. In Experiment 1, mares were treated with reLH from Day 7 to Day 15 (Day 0=ovulation), PGF2α on Day 7, or in combination. In Experiment 2, FM at doses of 2.0 or 3.0 mg/kg every 12 h and human chorionic gonadotropin (hCG) (1500 IU) were administered after a follicle ≥32 mm was detected. In Experiment 3, FM at a dose of 2.0 mg/kg every 12 h plus hCG was used to induce LUFs and investigate the intrafollicular endocrine milieu. No LUFs were induced by reLH or PGF2α treatment; however, LUFs were induced in 100% of mares using FM. Intrafollicular PGF2α metabolite, PGF2α, and PGE2were lower and the ratio of PGE2:PGF2α was higher in the induced LUF group. Higher levels of intrafollicular E2 and total primary sex steroids were observed in the induced LUF group along with a tendency for higher levels of GH, cortisol, and T; however, LH, PRL, VEGF-A, and NO did not differ between groups. In conclusion, this study reveals part of the intrafollicular endocrine milieu and the association of prostaglandins in LUF formation, and indicates that the mare might be an appropriate model for studying the poorly understood LUF syndrome.

Ultrasound characteristics of experimentally induced luteinized unruptured follicles (LUF) and naturally occurring hemorrhagic anovulatory follicles (HAF) in the mare

The development of hemorrhagic anovulatory follicles (HAF) involves luteinization and hemorrhage of the follicle. This is observed on ultrasound as an increase in the echogenicity of the granulosa layer and formation of echoic particles in the antrum. The inhibition of prostaglandin synthesis with flunixin meglumine (FM) during the periovulatory period induces ovulatory failure with development of luteinized unruptured follicles (LUF). These two types of anovulatory follicles appear to share similar ultrasound features but they have not been compared critically. The following endpoints: follicle diameter, follicular contents score, interval from hCG administration to beginning of follicular hemorrhage, interval from hemorrhage to organization of follicular contents, and cycle length were studied and compared in mares with HAF (n = 11) and LUF (n = 13). The objective of this study was to elucidate whether these two unruptured follicles have a consistent clinical pattern of development and therefore can be considered as part of the same anovulatory syndrome. None of the endpoints analyzed differed significantly between HAF and LUF. However, there was a greater individual variation in HAF as compared with LUF in regards to interval from hCG to hemorrhage, follicular diameter at the administration of hCG, and beginning of hemorrhage. In conclusion, HAF share a similar cascade of ultrasound characteristics with the experimentally induced LUF. This finding may provide new insights in elucidating the pathogenesis of HAF.

Luteinized unruptured follicle syndrome: incidence and recurrence rate in infertile women with unexplained infertility undergoing intrauterine insemination

BACKGROUND

The objective of this study was to determine the incidence and recurrence rate of luteinized unruptured follicle (LUF) syndrome in women with unexplained infertility undergoing intrauterine insemination (IUI).

METHODS

A total of 167 women with unexplained infertility who underwent 292 cycles of IUI were enrolled in the study. All patients were treated with clomiphene citrate, 50-150 mg/daily from day 5 to 9 of their menstrual cycle. Ultrasound examination to confirm ovulation was performed on the day of IUI (day 0) and every day thereafter for another 3 days (days 1, 2 and 3). A total of 69 women who failed to conceive in the first cycle and 56 women who failed to conceive in the second cycle underwent second and third cycles, respectively.

RESULTS

Of the total 167 patients who underwent first cycle, 42 (25%) had LUF. The incidence of LUF was 56.5% in 69 patients who underwent a second cycle of IUI treatment, of whom 33 patients had LUF in the first cycle with recurrence rate of 78.6%. In 56 patients who underwent 3 consecutive cycles, the incidence of LUF was 58.9% and recurrence rate of 90%. No pregnancies were recorded in patients with LUF during the study period.

CONCLUSION

The incidence and recurrence rate of LUF are significantly increased in subsequent cycles of IUI. In these patients, other options of infertility treatment might be justified.

Women with ovulatory dysfunction undergoing ovarian stimulation with clomiphene citrate for intrauterine insemination may benefit from administration of human chorionic gonadotropin

OBJECTIVE

To investigate factors that may affect pregnancy outcome following ovarian stimulation with clomiphene citrate (CC) combined with intrauterine insemination (IUI).

DESIGN

Retrospective cohort study.

SETTING

University teaching hospital.

PATIENT(S)

Three hundred and twenty women who underwent 691 ovarian stimulation cycles with CC for IUI.

INTERVENTION(S)

Ovarian stimulation with CC followed by a single IUI either 24 hours after a spontaneous serum LH surge (>25 mIU/mL) or 36 hours after intramuscular human chorionic gonadotropin (hCG) administration (10,000 IU) when the largest follicle had reached a diameter of 17 mm.

MAIN OUTCOME MEASURE(S)

Clinical pregnancies.

RESULT(S)

Women with ovulatory dysfunction who received hCG had significantly higher pregnancy rates (24.6%) compared with women with other types of infertility. There were no differences in pregnancy rates between the LH surge group and the hCG group (14.3% vs 12.4%). A spontaneous LH surge was noted in a variety of follicular sizes (14 to 35 mm). There was no correlation for age, body mass index, follicular diameter, number of mature follicles, other sperm characteristics, and pregnancy outcome in either group.

CONCLUSION(S)

After ovarian stimulation with CC, IUI is equally effective 24 hours after a spontaneous LH surge or 36 hours after administration of hCG. Spontaneous LH surges were observed at a variety of follicular sizes with comparable pregnancy rates. In women with ovulatory dysfunction, hCG administration before insemination may be beneficial.

Plasma substance-P and substance-K and gonadal steroids in relation to the gonadotropin surge in normal human reproductive cycles

PURPOSE

This study was designed to examine changes in peripheral plasma substance-P and -K levels, their association with follicle-stimulating hormone and luteinizing hormone release in normal reproductive cycles in humans, and their correlation with plasma estradiol and progesterone.

METHODS

Fourteen healthy, normally menstruating women underwent daily blood sampling (cycle day 4, 4-14 days) for measurement of estradiol, progesterone, luteinizing hormone, and follicle-stimulating hormone, substances-P and -K, and daily transvaginal ultrasounds assessing follicular growth and documentation of ovulation.

RESULTS

Estradiol peaked on day 13, luteinizing hormone and follicle-stimulating hormone peaked on day 14, and progesterone began an exponential increase on about day 13.

CONCLUSIONS

In contrast to other experimental designs using in vitro or in vivo rat or monkey tissue, peripheral levels of substances-P (P = 0.8391) and -K (P = 0.3205) reflected no modulation related to midcycle gonadotropin release in cycling woman.

Midcycle administration of a progesterone synthesis inhibitor prevents ovulation in primates

Progesterone receptors appear in granuloma cells of preovulatory follicles after the midcycle gonadotropin surge, suggesting important local actions of progesterone during ovulation in primates. Steroid reduction and replacement during the gonadotropin surge in macaques was used to evaluate the role of progesterone in the ovulatory process. Animals received gonadotropins to induce development of multiple preovulatory follicles, followed by human chorionic gonadotropin (hCG) administration (day 0) to promote oocyte (nuclear) maturation, ovulation, and follicular luteinization. On days 0-2, animals received no further treatment; a steroid synthesis inhibitor, trilostane (TRL); TRL + R5020; or TRL + dihydrotestosterone propionate (DHT). On day 3, ovulation was confirmed by counting ovulation sites and collecting oviductal oocytes. The meiotic status of oviductal and remaining follicular oocytes was evaluated. Peak serum estradiol levels, the total number of large follicles, and baseline serum progesterone levels at the time of hCG administration were similar in all animals. Ovulation sites and oviductal oocytes were routinely observed in controls. Ovulation was abolished in TRL. Progestin, but not androgen, replacement restored ovulation. Relative to controls, progesterone production was impaired for the first 6 days post-hCG in TRL, TRL + R5020, and TRL + DHT. Thereafter, progesterone remained low in TRL but recovered to control levels with progestin and androgen replacement. Similar percentages of mature (metaphase II) oocytes were collected among groups. Thus, steroid reduction during the gonadotropin surge inhibited ovulation and luteinization, but not reinitiation of oocyte meiotic maturation, in the primate follicle. The data are consistent with a local receptor-mediated role for progesterone in the ovulatory process.

Adverse effects of fertility drugs

Ovulation-induction agents are commonly used in the treatment of infertility in patients with or without ovulatory disturbances. These agents include clomifene, bromocriptine, gonadotrophin preparations and gonadotrophin-releasing hormone (GnRH) and its analogues. Each agent is associated with its own specific adverse effects. Although many of these adverse effects are benign and self-limited, some, in particular those effects associated with gonadotrophins, may be life-threatening. Commonly noted adverse effects encountered with the use of pharmacological agents to treat infertility include the following. Clomifene has been associated with hot flushes, multiple gestation, visual disturbances, cervical mucus abnormalities and luteal phase deficiency. Similarly, most of the adverse symptoms associated with bromocriptine are short-lived, such as nausea and postural hypotension. On the other hand, gonadotrophin therapy, even when used appropriately, may lead to the ovarian hyperstimulation syndrome (which is occasionally life-threatening) and a high incidence of multiple gestation. Pulsatile GnRH therapy maybe accompanied by similar adverse effects to those of gonadotrophins, but with a far lower incidence. With regards to the long term safety of these medications, the relationship between fertility drugs and epithelial ovarian cancer is controversial, and causality has yet to be proven. Indeed, a working knowledge of the many adverse effects associated with these medications is essential to any physician prescribing ovulation induction agents, in order to ensure maximum patient safety, compliance and understanding.

The presence of luteinized unruptured follicle syndrome and altered folliculogenesis in rats with surgically induced endometriosis

OBJECTIVE

Our purpose was to determine in the rat model whether endometriosis could influence ovarian function by altering oocyte release or folliculogenesis.

STUDY DESIGN

We histologically examined the ovaries of reproductively cycling rats with (n = 16) and without (n = 10) surgically induced endometriosis. The rats in these two groups were further subdivided into unilaterally ovariectomized or ovarian-intact groups. Serial sections of ovaries were examined, and follicular development and frequency of luteinized unruptured follicles were determined.

RESULTS

A significant tenfold increase in the number of luteinized unruptured follicles was observed in the ovaries from rats with endometriosis (2.7 per rat) compared with unoperated and sham-operated control groups (overall mean 0.26 per rat, p < 0.05). Additionally, ovaries from unilateral ovariectomized animals with endometriosis contained four times as many luteinized unruptured follicles (four per rat) as did the ovaries from bilaterally ovarian-intact rats with endometriosis (1.40 per rat, p < 0.01). Fewer follicles were present in rats with endometriosis (180 follicles per ovary) than in control rats (231 follicles per ovary, p < 0.05).

CONCLUSION

In the rat model the presence of ectopic endometrium is associated with an increased frequency of luteinized unruptured follicles and altered follicular development.

Comparison of hCG versus GnRH analog for releasing oocytes following ultra low-dose gonadotropin stimulation

Previous data have suggested there is a higher incidence of luteinized unruptured follicle (LUF) syndrome (defined as failure to release any oocyte as determined by sonography) in gonadotropin-treated patients following human chorionic gonadotropin (hCG) versus the gonadotropin releasing hormone agonist (GnRH-a) leuprolide acetate. The present study was designed to determine if an ultra low-dose gonadotropin regimen, designed not to raise the serum estradiol level much above normal for non-stimulated cycles, might result in a decrease in LUF following hCG treatment, and even reduce the rate to that seen following leuprolide acetate. The hypothesis tested was that the higher estradiol levels might suppress the pre-ovulatory follicle stimulating hormone (FSH) surge which, in turn, would inhibit plasmin production, thus preventing detachment of the oocyte from the follicle. The data did show a reduced rate of LUF incidence with either hCG or leuprolide acetate in ultra low-dose human menopausal gonadotropin-(hMG-) treated patients compared to data from previous studies with conventional hMG/hCG therapy. Pregnancy rates were also similar following hCG or leuprolide acetate for release in low-dose hMG-treated patients. Preliminary data show that leuprolide acetate is superior to hCG for causing oocyte release when stimulation is with low-dose purified FSH, and possibly also that low-dose hMG is superior to low-dose purified FSH for producing superior pregnancy rates.

The origin of estrogens, progesterone, androgens and sex hormone binding globulin in peritoneal fluid in the immediate postovulatory period in normal ovulating women

In 20 women with proven fertility, one menstrual cycle was monitored by ovarian ultrasonography, laparoscopy and estimation of 17 beta-estradiol (E2), estrone (E1), progesterone, testosterone, androstenedione (Adion), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), and sex hormone binding globulin (SHBG) in serum and peritoneal fluid. Three groups were studied, in which the peritoneal fluid was collected within 1, 3 and 5 days after ovulation. E1, E2 and progesterone levels in peritoneal fluid were highest shortly after ovulation and decreased with time. Testosterone and Adion in peritoneal fluid showed no changes, but peritoneal fluid levels were always higher than serum levels. No differences were found between the peritoneal fluid and serum levels of DHEA and DHEAS. SHBG in serum was always higher than in peritoneal fluid. The results are compared with reported steroid levels in follicular fluid from the literature and factors complicating the interpretation of steroid levels in peritoneal fluid are discussed.