The relation of serum and follicular fluid leptin and ovarian steroid levels in response to induction of ovulation in in vitro fertilization cycles

OBJECTIVE: Leptin restores energy homeostasis and regulates appetite and body weight by communicating the energy status to the central nervous system. Although there is strong evidence that leptin affects reproduction, its role in the control of reproductive physiology is little understood. STUDY DESIGN: We studied leptin concentrations in the serum and follicular fluid of 65 women undergoing ovarian hyperstimulation for in vitro fertilization (IVF). Fasting serum samples were collected (1) on the 3rd day of the cycle before IVF and (2) at the time of oocyte retrieval. Serum concentrations of leptin, estradiol (E2), progesterone, FSH, LH, prolactin, total testosterone, DHEA-SO4, and TSH and follicular fluid concentrations of leptin, E2, and progesterone were measured. RESULTS: Serum leptin values increased on average by 66.4% over basal leptin levels on the day of oocyte pick-up (OPU). A positive correlation between leptin increase and body mass index was observed. The serum leptin level was similar to that in follicular fluid o the day of OPU. E2 levels increased 34.5-fold with controlled ovarian hyperstimulation. There was a negative correlation between the increase in leptin levels and in E2 levels (P <0.05) and in the number of oocytes harvested (P <0.05). CONCLUSION: The significant increase in serum leptin levels during controlled ovarian hyperstimulation indicates a possible role of leptin in reproductive function. The increase in leptin levels is negatively correlated with ovarian response evaluated by E2 production and number of oocytes retrieved. This might be due to the reduced ovarian response through negative feedback of leptin to the ovaries at high levels.     

Effects of ovulation induction on ovarian morphology: an animal study

OBJECTIVE: The aim of this study was to investigate whether the ovulation induction has relation with postneoplastic lesions. MATERIALS AND METHODS: Seventy-eight female, 90-day-old rats were enrolled for the trial. They were divided into three groups. In the first group, 13 rats received one cycle of ovulation induction with Follitropin Beta and human chorionic gonadotropin. The second group of 13 rats received three cycles of ovulation induction, and the third study group consisted of 13 rats which received six cycles of ovulation induction. Each group had a control group consisting of same number of rats that had not received ovulation induction. At the 12th month after the ovulation induction protocols ended, rat ovaries were extirpated for histopathological examination. In histopathological examination, malignant lesions, ovarian cyst and cyst diameter, epithelial stratification, epithelial tufting, mitotic index, polymorphism of epithelial cells and nucleus, epithelial cell nuclear diameter, chromatin density nuclear atypia, and mitotic activity in ovarian cyst epithelium were evaluated. RESULTS: No malignant ovarian lesion was found in the three groups. Ovarian cyst development was most frequent in the rats that underwent six cycles of ovulation induction. Epithelial stratification and tufting were most frequent in the rats which underwent ovulation induction six times. Significant difference was found between induction and control groups in second and third groups for cellular and nuclear polymorphism, presence of nucleolus, and nuclear chromatin density. CONCLUSIONS: Although development of malignant lesion were not found in any of the rat ovaries after ovulation induction, increase in the prevalence of epithelial dysplasia especially with increase in the number of induction cycles shows that some ovarian pathologies can occur subsequent to ovulation induction.     

Expression of ovarian prolactin receptor in relation to hormonal changes during induction of ovulation in the rat

We examined the relationships between the expression of the short and long forms of the prolactin (PRL) receptor (PRLR) mRNA in the ovary and changes in the levels of serum hormones such as sex steroid hormones and PRL during induction of ovulation in the rat. The expression of both forms of PRLR mRNA in the ovary was examined by Northern blot analysis in immature female rats treated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). Ovarian tissues and blood samples were obtained before treatment, 24 and 48 h after PMSG injection and 4, 6, 8, 12, 24 and 48 h after hCG treatment. Serum levels of 17beta-estradiol, progesterone and PRL were determined by radioimmunoassay. Serum levels of 17beta-estradiol rapidly increased to a maximal level 48 h after PMSG injection and then rapidly declined until 4 h after hCG injection. Serum levels of progesterone gradually increased after PMSG treatment, markedly increased to 114.2 nmol/l 8 h after hCG treatment and remained high until 48 h after hCG treatment. The serum level of PRL peaked at 66.2 microg/l (p < 0.01) 48 h after PMSG injection, and a temporary decrease after hCG treatment was followed by a continuously high level from 8 to 48 h. The expression of the long form of PRLR mRNA increased significantly (p < 0.01) to 688% of the control level after PMSG treatment, while that of the short form increased to only 184% of the control level. The expression of the long form of PRLR-mRNA rapidly declined until 6 h and then gradually increased until 48 h after hCG treatment. On the other hand, the expression of the short form of PRLR mRNA decreased to a nadir 12 h after hCG injection and then increased significantly (p < 0.01) to 142% of the control level. Our results showed that the changes in the short and long forms of PRLR mRNA differed in a time-specific manner and that these two forms are involved in different functions in the rat ovary during induction of ovulation. It is thought that the long form of PRLR mRNA is involved in folliculogenesis, while the short form of PRLR mRNA may play an important role in the formation and maintenance of the corpus luteum in the rat ovulatory cycle.     

Cerebrospinal fluid leptin levels in preeclampsia: relation to maternal serum leptin levels

BACKGROUND: To determine whether cerebrospinal fluid (CSF) and circulating levels of leptin differ between women with preeclampsia and women who had an uncomplicated pregnancy. METHODS: Maternal serum and CSF leptin concentrations obtained in the third trimester of the gestation were compared in 16 women with mild preeclampsia and 23 normotensive pregnant women who underwent cesarean section. Before administering local anesthetic for spinal anesthesia, 2 mL CSF and 4 mL venous blood sample were taken and were stored at -30 degrees C until serum and CSF leptin levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Mean CSF leptin concentrations were not significantly different between the two groups (preeclampsia 9.7 +/- 4.2 ng/mL, normotensive 13.6 +/- 4.3 ng/mL, p = 0.952). Similarly, mean serum leptin concentrations were similar between the two groups (mild preeclampsia 21.7 +/- 7.1 ng/mL, normotensive 18.3 +/- 6.7 ng/mL, p = 0.698). CSF leptin levels are inversely related to the serum leptin concentrations in preeclamptic patients (r = -0.87, p = 0.000). An inverse relationship was also detected between CSF and serum leptin levels in normotensive pregnant subjects (r = -0.66, p = 0.000). CONCLUSIONS: CSF and serum leptin levels were similar in patients with preeclampsia and normotensive pregnant women. However, the CSF leptin was negatively correlated with the serum leptin concentrations in preeclamptic and normotensive control subjects, suggesting that leptin enters the brain by a saturable transport system. Further work is needed to confirm our findings.     

Premature ovarian failure: predictability of intermittent ovarian function and response to ovulation induction agents

PURPOSE OF REVIEW: To summarize our current knowledge about the predictability of intermittent ovarian function and the response to ovulation induction agents in patients with premature ovarian failure. RECENT FINDINGS: In addition to clinical, histological or ultrasonographic features, a new biological marker anti-Müllerian hormone, was evaluated as a marker for ovarian reserve in premature ovarian failure patients with encouraging results. Moreover, even if no treatment has proven to be effective enough to restore ovarian function, a recent study has presented a therapeutic protocol leading to a significant increase in ovulation and a higher pregnancy rate. SUMMARY: Intermittent ovarian function can be spontaneously observed in premature ovarian failure patients. Clinical, biological and ovarian ultrasonographic features may allow an assessment of the presence of ovarian activity, but are not necessarily correlated with a higher ovulation or pregnancy rate. Nevertheless, it appears essential to characterize these patients to determine whether some of them could be candidates who benefit from a particular therapeutic strategy, although most such strategies have not yet demonstrated their efficiency.     

Ovarian epithelial dysplasia in relation to ovulation induction and nulliparity

OBJECTIVE: The goal of this study was to assess the relationship between ovulation induction, nulliparity, and ovarian epithelial dysplasia. METHODS: This retrospective cohort study was performed in one teaching and one district general hospital in London. The subjects, 83 women who had undergone hysterectomy and bilateral oophorectomy and whose ovaries were reported as "normal," were divided into three groups: ovulation induction (13), nulliparity (20), and fertile controls (50). These ovaries were independently reviewed by two pathologists who assigned a score of 0, 1, or 2 to nine epithelial cytological and architectural features. The main outcome measure was the total dysplasia score, which was used to quantify the degree of ovarian epithelial abnormality in the three groups. RESULTS: The mean dysplasia score was significantly higher in the women who had undergone ovulation induction than in the fertile controls (7.92 vs 5.70, P = 0.012). The magnitude of the difference between the ovulation induction group and controls remained similar after adjusting for age, parity, and duration of oral contraceptive use (2.17, 95% CI: -0.11-4.44). However, the statistical significance of this difference was reduced (P = 0.062). We did not find any evidence of a difference in dysplasia score between nulliparous women and controls, neither before (P = 0.85) nor after adjusting for age and duration of oral contraceptive use (P = 0.87). CONCLUSIONS: These results suggest a possible association between ovarian epithelial dysplasia and ovulation induction therapy, in accord with previous reports of increased risk of ovarian cancer in women with a history of fertility treatment. The higher dysplasia score could be attributable to the drugs used to induce ovulation or to a genetic susceptibility to ovarian cancer.     

Leptin and ovarian folliculogenesis: implications for ovulation induction and ART outcomes

Leptin participates in regulation of ovarian folliculogenesis indirectly via control of luteinizing hormone and follicle-stimulating hormone secretion. More recent evidence suggests that leptin also has direct regulatory actions on the developing follicle. The presence of leptin receptors on follicular cells, including oocytes, and early preimplantation embryos suggests that leptin may play a direct physiologic role in follicular maturation, oocyte development, and early cleavage. Because circulating leptin levels are directly related to body adiposity, elevated leptin concentrations associated with obesity may partly explain the negative impact of obesity on fertility. The influence of leptin on follicular development and oocyte maturation has important implications for ovulation induction and assisted reproductive technologies. Moreover, polycystic ovarian syndrome may be associated with altered leptin phsyiology.     

Regression of ovarian enlargement in pharmacological ovulation induction

The aim of the present study was to determine a possible relationship between ovarian functionality and regression of ovarian enlargement according to the different categories and degree of severity of ovarian hyperstimulation syndrome (OHSS). Among a group of sterile woman (n = 111) ,two subgroups were studied: group A (n = 15) ,patients affected by severe syndrome; and group B (n = 96) ,patients with massive ovarian enlargement only. The protocol of ovarian stimulation was conducted in various in vitro fertilization (IVF) centers; ultrasonographic examination and hematological checks were carried out daily; patients with severe OHSS were hospitalized. In women of group A ,severe symptoms disappeared in 7–11 days; in nine patients with regular cycles ovary size returned to normal in about 30–40 days ,whereas in six subjects with anovulatory cycles ,the resolution was recorded in about 50–60 days; serum estradiol returned to physiological levels within 20–30 days. Women of group B showed a spontaneous regression at different times: in 43 subjects that presented regular ovulatory cycles ,the resolution was recorded in about 30–40 days ,whereas in 36 women with anovulatory cycles before pharmacological induction ,resolution occurred in 50–60 days ,and in 17 cases with polycystic ovary syndrome before pharmacological ovulation ,an incomplete resolution was obtained; serum estradiol levels returned to a physiological range within 20–30 days. Our results show that in patients with regular ovulatory cycles ,resolution of symptoms is obtained in a shorter time than in patients with anovulatory cycles before pharmacological induction.     

Basal ovarian cysts and clomiphene citrate ovulation induction cycles

OBJECTIVE: To evaluate the effect of simple basal ovarian cysts in patients undergoing infertility treatment with clomiphene citrate. To evaluate the effect of clomiphene citrate on pretreatment simple ovarian cysts. METHODS: Prospective cohort trial of 84 infertility patients undergoing ovulation induction with clomiphene citrate. Patients with basal ovarian cysts of 10 mm or greater (n = 42) were compared with patients without ovarian cysts (n = 42). The main outcome measure was ovulation determined by menstrual cycle day 21 progesterone level. Each patients with an ovarian cyst was also evaluated for persistence or resolution of the cyst in association with ovulation and cyst size. Pretreatment and posttreatment transvaginal ultrasound examinations were performed on all patients. RESULTS: Demographic data were similar among the groups. The mean ovarian cyst size was 17.4 +/- 5.8 mm. Patients in the ovarian cyst group were significantly less likely to ovulate (80.9% versus 97.6%, P < .05), but did not differ in pregnancy rate compared with patients without baseline ovarian cysts (4.8% versus 11.9%, P = .43). Persistent ovarian cysts occurred in 36.7% of the patients. The initial size of the cyst did not predict cyst persistence. CONCLUSION: According to these data, basal ovarian cysts significantly reduce ovulatory events in patients treated with clomiphene citrate. LEVEL OF EVIDENCE: II-2.     

From pathological diagnosis to ovulation induction. The case of ovarian insufficiency

The incidence of premature ovarian failure (POF) is around 1 to 3%. This pathology occurs in young women, who often wish to become pregnant. Theoretically, two mechanisms could be involved: initial follicle depletion and follicle dysfunction. However, in some cases, mixed mechanisms are involved. Initially, PFO was considered irreversible. In fact, signs of intermittent ovarian function in normal karyotypically women have been described, but predicting the probability of spontaneous remission in a specific woman is impossible. Therefore, various treatments for ovulation induction have been proposed to these patients. Most of the pregnancies occur after hormone replacement therapy. The action of this treatment is unclear and the cause-and-effect relation has not been proven by prospective, randomized studies. The benefit of suppressing endogen gonadotropins by GnRH agonists is not proven either. Estrogen supplementation and high-dose gonadotropin ovarian stimulation protocols have been proposed. Even so, this therapy cannot be recommended because of the lack of controlled studies. Finally, numerous case reports have described the return of ovarian function after using immunosuppressive therapies. The lack of particular criteria for the diagnosis of autoimmune mechanisms have lead to treat heterogeneous groups of patients. No randomized controlled studies with immunologic monitorage have been performed that could establish the success of this therapy. Therefore, in order to find effective treatments, basic pathophysiologic mechanisms must be better understood. For those women who want to become pregnant, the lack of prospective, randomized studies cannot lead to formal conclusions. Depending on the patients' age and history, it appears reasonable to attempt a corrective therapy based on defined etiology, before entering in a donor oocyte program.     

Alternate regimens for ovulation induction in polycystic ovarian disease

The patient with PCOD remains a challenge to the reproductive endocrinologist. Although successful induction of ovulation can often be achieved using standard therapeutic regimens of CC or hMG, too often this group of anovulatory patients fails to respond as expected. Over the past 10 to 15 years, alternate approaches to ovulation induction have been investigated with encouraging results. Whereas no one method is productive in all patients, these varied regimens offer us a number of options in dealing with this difficult clinical problem.     

Regression of ovarian enlargement in pharmacological ovulation induction.

The aim of the present study was to determine a possible relationship between ovarian functionality and regression of ovarian enlargement according to the different categories and degree of severity of ovarian hyperstimulation syndrome (OHSS). Among a group of sterile woman (n = 111), two subgroups were studied: group A (n = 15), patients affected by severe syndrome; and group B (n = 96), patients with massive ovarian enlargement only. The protocol of ovarian stimulation was conducted in various in vitro fertilization (IVF) centers; ultrasonographic examination and hematological checks were carried out daily; patients with severe OHSS were hospitalized. In women of group A, severe symptoms disappeared in 7-11 days; in nine patients with regular cycles ovary size returned to normal in about 30-40 days, whereas in six subjects with anovulatory cycles, the resolution was recorded in about 50-60 days; serum estradiol returned to physiological levels within 20-30 days. Women of group B showed a spontaneous regression at different times: in 43 subjects that presented regular ovulatory cycles, the resolution was recorded in about 30-40 days, whereas in 36 women with anovulatory cycles before pharmacological induction, resolution occurred in 50-60 days, and in 17 cases with polycystic ovary syndrome before pharmacological ovulation, an incomplete resolution was obtained; serum estradiol levels returned to a physiological range within 20-30 days. Our results show that in patients with regular ovulatory cycles, resolution of symptoms is obtained in a shorter time than in patients with anovulatory cycles before pharmacological induction.     

The use of ovarian ultrasonography in monitoring ovulation induction

Ovarian ultrasonography is a new diagnostic technique which has become almost essential in monitoring ovulation. Recent improvements in ultrasound technology have allowed for accurate assessment of the number and size of the developing follicles and their rate of growth, as well as ovulation and postovulatory events. In the non-stimulated cycle follicular size correlates well with optimal maturation and there is a linear correlation between follicular diameter and plesma estradiol (E₂ levels). In stimulated cycles, because of asynchrony of various recruited coliorts of follicles, these rules are not as steadfast, These observations indicate that when there is endogenous gonadotropic activity, follicular growth stimulated by human menopausal gonadotropins (hMG) does not develop synchronously. The aim should be, therefore, not only to improve the monitoring system but mainly to synchronize the cohorts of follicles recruited for development in any one cycle by a better regimen for ovalation induction. In view of the high success rate of hMG treatment in patients without endogenous gonadotropin secretion, it is tempting to speculate that inducing similar conditions in women with endogenous gonadotropin production may have a significant change in the pattern of follicular development in their conception rate.     

Cell cycle and apoptotic proteins in relation to ovarian epithelial morphology

OBJECTIVE: To assess the relationship between the expression of cell cycle and apoptotic proteins and the morphological appearance of the surface epithelium in non-neoplastic ovaries. METHODS: The subjects for this study were 79 women who had undergone oophorectomy for benign conditions at the North Middlesex Hospital, London, and Royal Free Hospital, London, and whose ovaries had been reported on routine histology as entirely normal or containing physiological cysts or endometriosis. The epithelial morphology was reassessed on haematoxylin and eosin-stained paraffin wax sections using nine cytological and architectural parameters associated with premalignant intraepithelial changes. A 'score' was obtained for each ovary. Expression of p53, Ki67, cyclin D1 and Bcl-2 in the surface, cystic and endometriotic epithelium was assessed in corresponding sections using standard immunohistochemistry. RESULTS: The median score for the morphological changes was significantly higher in the sections, which expressed p53 compared to those which did not. This difference remained significant in a subanalysis of the sections, which did not contain endometriosis. No relationship was identified between the morphological score and the expression of Ki67, Bcl-2 and cyclin D1. CONCLUSION: Increased intraepithelial abnormality as assessed by an epithelial morphological score of ovarian sections is associated with expression of the p53 cell cycle protein. This lends credence to the hypothesis that the ovarian surface or cystic epithelium goes through an identifiable precursor or "premalignant" phase before the development of invasive disease. Further work is required to characterise the changes that take place before the development of malignancy in ovarian epithelium.