The ovarian hyperstimulation syndrome

The role of osmoregulation in the pathophysiology and management of severe ovarian hyperstimulation syndrome

Severe ovarian hyperstimulation syndrome (OHSS), with an incidence of 1-2% of superovulation cycles, remains one of the most important complications of gonadotrophin use in assisted reproductive technologies because of its associated morbidity and rarely, mortality. Despite the wealth of scientific and clinical interest that this iatrogenic complication has generated, its pathophysiology is still not adequately elucidated and its management has thus remained empirical. Disorders of salt and water balance are two very important features that have been reported during severe OHSS. Some of the clinical and biochemical changes resulting from this disorder of salt and water balance are similar to those previously reported in pregnancy and liver cirrhosis. The pathophysiology of these clinical changes has been explained in part in pregnancy and liver cirrhosis by changes in osmoregulation function. It is this similarity in the clinical and biochemical changes in OHSS, pregnancy and liver cirrhosis that has prompted the investigation of the role of osmoregulation function in the pathophysiology of OHSS. The current article has been written to provide further details in support of recent excellent articles and guidelines, highlighting the physiological basis and rationale governing some aspects of, and the role of osmoregulation in the management of the OHSS syndrome.

Mild/minimal stimulation protocol for ovarian stimulation of patients at high risk of developing ovarian hyperstimulation syndrome

BACKGROUND

Recently, an increased scientific interest was focused on mild approaches for ovarian stimulation in clinical practice. Milder stimulation aims to develop safer and more patient-friendly protocols which are more physiological, less drug use, less expensive and the risks of treatment are highly minimized.

AIM

To investigate the efficacy and safety of a mild ovarian stimulation protocol in patients at high risk of developing ovarian hyperstimulation syndrome (OHSS), compared to conventional long down-regulation protocol.

SUBJECTS AND METHODS

This a prospective, open, randomized study, included 349 infertile patients considered at high risk of developing OHSS, undergoing in vitro fertilization treatment in two private assisted reproduction centers. The patients were randomized into two groups: group A (n = 148) had a mild/minimal stimulation protocol of recombinant FSH (rFSH) combined with GnRH antagonist. Group B (n = 201) (control group) had a standard long protocol of rFSH combined with GnRH agonist.

RESULTS

There was no significant difference observed between the two groups regarding the mean number of oocytes retrieved per patient, mature metaphase II oocytes, fertilization rate, and embryo cleavage rate. Significantly higher implantation rate (21.5 vs 14.5 %) (p < 0.05), pregnancy rate (37.7 vs 23.4 %) (p < 0.05), and delivery rate (32.8 vs 20.1 %) (p < 0.05) were observed in favor of groups A compared to group B. Lower proportion of patients (4.7 %), though not statistically significant, has developed OHSS in group A compared to group B (8.4 %).

CONCLUSION

Our study shows that mild stimulation regimen is highly effective for ovarian stimulation of patients who have experienced OHSS complication without increasing the risk of OHSS.

Hyperstimulation ovarienne : place de la chirurgie

Ovarian hyperstimulation syndrome is a iatrogenic complication that could happen during ovulation induction. Metabolic modifications can lead to a third sector and organic failure. Medical treatment, undertaken in first line, may be insufficient. In these cases, invasive treatment, using surgical techniques, in association with reanimation principles becomes necessary. From the simple drainage to final measures for the patient's rescue, this review describes the different solutions and their respective place. Several means exist, but serious evaluation is lacking. Their use should be indicated specifically. Medico-surgical associations seemed to offer interesting results.

Fertility drug therapies: past, present, and future

Throughout the last 30 years there has been an evolution of drug therapies aimed at the treatment of infertility. These agents primarily address the induction of ovulation or enhancing ovulation by allowing more oocytes to mature simultaneously. As this evolution has progressed, drugs have moved away from human products to the advent of the recombinant or genetically engineered technology. The drugs have not cured infertility, but they have affected positively the quest of families confronted by infertility.

Elective cryopreservation of all pronucleate embryos in women at risk of ovarian hyperstimulation syndrome: efficiency and safety

In a prospective randomized study, we analysed 125 patients at risk of ovarian hyperstimulation syndrome (OHSS), selected in the period between January 1996 and July 1997. All the patients had blood oestradiol concentration >/=1500 pg/ml on the day of human chorionic gonadotrophin (HCG) administration and >/=15 oocytes were collected. The patients were matched in two groups: group A, control group (n = 67), had fresh embryo transfers; group B (n = 58) had cryopreservation of all obtained pronucleate embryos. Pregnancy, live birth rates and the incidence of OHSS were compared between the two groups. There were no significant differences in terms of pregnancies per patient (46.3 versus 48.3%) and live birth rates (38. 8 versus 39.6%). No cases of OHSS occurred in group B, while four patients developed the syndrome in group A. The implantation rate was slightly but not significantly lower in group B (chi2 = 1.03). These results suggest that elective cryopreservation of all zygotes might prevent the risk of OHSS in patients undergoing IVF treatment. In contrast to what has been reported by other authors, our results show that the elective cryopreservation of zygotes does not affect pregnancy and live birth rates.

Prospective study of the clinical and laboratory parameters of patients in whom ovarian hyperstimulation syndrome developed during controlled ovarian hyperstimulation for in vitro fertilization

OBJECTIVE

To compare patient characteristics and clinical and laboratory parameters in patients in whom ovarian hyperstimulation syndrome (OHSS) develops with those in whom it does not develop.

DESIGN

Prospective cohort study.

SETTING

Reproductive medicine unit at a university medical center.

PATIENT(S)

All patients undergoing IVF (n = 428) who received controlled ovarian hyperstimulation during a 6-month period.

INTERVENTION(S)

Prospective data collection.

MAIN OUTCOME MEASURE(S)

Patient characteristics (age, body mass index, medical history, smoking habits) and clinical and laboratory data obtained during controlled ovarian hyperstimulation were evaluated in patients who had severe OHSS, any degree of OHSS, or a significant risk of OHSS and compared with the remaining populations.

RESULT(S)

Severe OHSS developed in 18 patients (4.2%) and mild or moderate OHSS developed in 7.3%. As a group, all the patients with OHSS were significantly younger, received lower doses of gonadotropins, had ovaries containing a higher number of total and large follicles, had a higher number of retrieved oocytes, and had a higher pregnancy rate than the patients without OHSS. The patients with severe OHSS also had an increased prevalence of allergy (56% versus 21%) and were more likely to ultimately give birth.

CONCLUSION(S)

The observed differences may be useful in elucidating the pathophysiology of OHSS and identifying patients who are at increased risk for OHSS.

Clinical review 100: Evaluation and treatment of the infertile couple

Infertility by itself does not threaten physical health but has a strong impact on the psychological and social well-being of couples. In the last two decades, progress in caring for the infertile couple, in particular progress in the field of assisted reproduction and micromanipulation, has provided significant hope for many couples for whom hope could not have been offered in the past. This is especially true for bilateral tubal disease and for male factor infertility, as nearly all couples with male factor infertility can now undergo either one (or more) IVF or ICSI attempt(s). For couples with other causes of infertility, however, the differences in pregnancy rates often do not reach statistical significance. We must also remember that the total cost incurred for successful delivery for couples with a better chance of successful IVF (i.e. those with tubal disease) increases from approximately $55,000 in American dollars for the first cycle to $73,000 by the sixth cycle. Because of these high costs, many insurers in the United States and many public health systems in Europe do not cover or only partially cover these procedures. Consequently, the availability of IVF and related therapies frequently depends on the couple's ability to pay. Therefore, after having established the correct diagnosis, appropriate treatment should be counseled to the infertile couple keeping in mind the following points: 1) in subfertile couples expectant management should be reasonably counselled if the age of the woman is less than 30 yr and the duration of infertility is less than 36 months, even if oligozoospermia is present; 2) superovulation and timed intercourse seems also to be a reasonable approach in couples with anovulatory, mild/moderate endometriosis, and unexplained infertility; 3) in unexplained infertility, ovarian stimulation (with clomiphene or gonadotropin) and IUI seem to offer some advantage over ovarian stimulation and timed intercourse; 4) IVF can be a firstline approach in tubal sterility and when IUI or IPI cannot be performed because the number of motile sperm is insufficient, but is usually also the final treatment attempt when other methods have failed. The outcome of IVF is negatively influenced mainly by the woman's age; however, the number of deliveries is also generally lower in couples with male factor; 5) ICSI is a further option, which should be limited to couples: a) with very poor semen parameters; b) previous failed fertilization; c) presence of obstructive or nonobstructive azoospermia in which ICSI is combined with sperm extraction from the epididymis or the testis; 6) international register studies demonstrate that the risk of malformation after conventional IVF is not increased; 7) some reports suggest that incidence of congenital major and minor malformations is not increased in children born after ICSI. However, the rate of sex chromosome anomalies in ICSI fetuses has been reported to be approximately 1% in 585 prenatal diagnoses, a frequency increased by a factor of 4 if compared with naturally conceived live-born babies. ICSI bypasses the physiological selection of spermatozoa that occurs at the level of the testis and epididymis, and in the female reproductive tract as well as at the sperm-oocyte interface. As genetic abnormalities are present in a significant percentage of infertile males with impaired spermatogenesis, karyotyping and analysis of the Y chromosome for microdeletions should be carried out in all potential ICSI fathers. Screening for cystic fibrosis gene mutations should also be performed in azoospermia caused by congenital absence of the vas deferens and seminal vesicles. Appropriate genetic counseling should be made available to all ICSI couples whenever a gene or chromosomal anomaly has been identified. With most ARTs the average delivery rate per cycle is approximately 15% and the cumulative delivery rate after several cycles is about 50%. (ABSTRACT TRUNCATED)