The pathogenesis of the ovarian hyperstimulation syndrome (OHS): a possible role for ovarian renin

Reproduction and the renin-angiotensin system

A unique aspect of the circulating renin-angiotensin system and the many independent tissue renin-angiotensin systems is their interactions at multiple levels with reproduction. These interactions, which have received relatively little attention, include effects of estrogens and possibly androgens on hepatic and renal angiotensinogen mRNA; effects of androgens on the Ren-2 gene and salivary renin in mice; the prorenin surge that occurs with but outlasts the LH surge during the menstrual cycle; the inhibitory effects of estrogens on thirst and water intake; the tissue renin-angiotensin systems in the brain, the anterior pituitary, and the ovaries and testes, that is, in all the components of the hypothalamo-pituitary-gonadal axis; the presence of some components of the renin-angiotensin system in the uterus and the fetoplacental unit; and the possible relation of renin and angiotensin to ovulation and fetal well-being. These interactions are described and their significance considered in this short review.

Total renin after gonadotropin stimulation in polycystic ovarian disease

OBJECTIVE

To examine the influence of polycystic ovarian disease (PCOD) on the levels of total renin in plasma and follicular fluid (FF) after stimulation with hMG.

DESIGN

Comparative study of the plasma and FF concentrations of total renin in women with and without PCOD after stimulation with hMG.

SETTING

In vitro fertilization-embryo transfer program at the Department of Obstetrics and Gynecology, the University Central Hospital of Turku, Finland.

PATIENTS

Thirty-six women undergoing IVF-ET for infertility with (n = 10) or without (n = 26) ultrasonographically diagnosed PCOD. Of the latter group, 15 women had tubal infertility, and the rest suffered from an anovulatory infertility and reacted with PCO-like ovarian response to stimulation.

MAIN OUTCOME MEASURES

The concentrations of total renin in plasma and FF, serum E2, and protein in FF.

RESULTS

The concentrations of plasma total renin after the gonadotropin stimulation were significantly higher in the PCOD and PCO-like groups when compared with the tubal group. The concentration of total renin in FF and the ratio of total renin per protein in FF were higher in the PCOD and PCO-like groups than in the tubal group, but the differences did not reach statistical significance. Positive correlations were found between the plasma total renin and serum E2 concentrations in the PCO-like and in the tubal group and between plasma total renin concentrations and the number of mature follicles in all groups. Follicular fluid total renin did not correlate with FF protein in any group. All findings were independent of the total hMG dosage used and the body mass index of the patients.

CONCLUSIONS

In the present study the concentrations of total renin in plasma were enhanced markedly after gonadotropin stimulation in women with PCOD compared with women having tubal infertility. The pattern of the hormonal secretions revealed a group of infertile patients reacting biochemically like women with PCOD.

Ovarian derived prorenin-angiotensin cascade in human reproduction

OBJECTIVE

To review the available literature concerning the renin-angiotensin system of the human and animal ovary and to outline the clinical relevance of this system.

DESIGN

The location, function, and regulation of the components of the ovarian prorenin cascade are described. The possible functions of this system as well as its association with common gynecologic problems are also given.

CONCLUSIONS

The ovary contains a complete cascade whose end product is the formation of angiotensin II. Angiotensin II may have a role in steroid synthesis, oocyte maturation, ovulation, and corpus luteum formation. Further, aberrations in this system are associated with ovarian tumors, ectopic pregnancy, pre-eclampsia, and ovarian hyperstimulation syndrome.

Angiotensin II immunoreactivity is elevated in ascites during severe ovarian hyperstimulation syndrome: implications for pathophysiology and clinical management

OBJECTIVE

To investigate the ovarian renin-angiotensin system (RAS) during severe ovarian hyperstimulation syndrome (OHSS).

DESIGN

Simultaneous sampling of blood and ascitic or peritoneal fluid (PF) during therapeutic paracentesis or laparoscopy.

SETTING

University Hospital.

PATIENTS

Twelve patients were investigated: three patients presenting severe OHSS, three patients with a spontaneous first trimester pregnancy, three normally cycling women during the early luteal phase, and three patients with ascites of nonovarian origin.

MAIN OUTCOME MEASURE

Renin-like activity and angiotensin II (ANG II) immunoreactivity were measured simultaneously in the plasma and the ascites or PF.

RESULTS

Angiotensin II immunoreactivity was much higher in the ascites or PF than in corresponding plasma during severe OHSS, first trimester pregnancy, and in the early luteal phase, while it was lower in ascites of nonovarian origin. Renin-like activity and ANG II immunoreactivity were the highest in the ascites of severe OHSS and in the PF from part of the patients with a spontaneous first trimester pregnancy.

CONCLUSIONS

The present findings argue for the ovarian origin of the elevated renin-like activity and ANG II immunoreactivity in the ascites of severe OHSS and suggest a stimulatory role of hCG on the ovarian RAS whether during severe OHSS or first trimester spontaneous pregnancy. The vasoactive peptide ANG II may contribute to the maintenance of the ascites in severe OHSS but is probably not responsible for the formation of the ascites. The efficiency of paracentesis during severe OHSS could be explained at least partially by the removing of great amounts of ANG II from the peritoneal cavity.

Complications of assisted reproductive techniques

OBJECTIVE

To review and appreciate the relevant data on assisted reproduction techniques and their potential complications.

DATA RESOURCES

Major publications on assisted reproduction that include the information concerning complications associated with this practice.

RESULTS

Assisted reproduction is a common practice in modern reproductive medicine. Complications are associated with ovulation induction and the extracorporeal methods that are used for IVF-ET, GIFT, and zygote intrafallopian transfer (ZIFT). These complications are associated with laparoscopy, anesthesia, oocyte retrieval, and laboratory facilities. Pregnancies resulting from assisted reproduction are more complicated than spontaneous pregnancies. There are higher rates of ectopic, heterotopic, and multifetal pregnancies; abortions; and premature deliveries. Increased rates of perinatal mortality and morbidity result from prematurity, and higher rates of maternal diseases in pregnancy (preeclampsia, diabetes mellitus, bleeding, anemia) contribute to fetal intra-uterine growth restriction and maternal morbidity.

CONCLUSIONS

Assisted reproduction practice should be well controlled in view of the potential for complications before and during pregnancies.

Increased ascitic fluid prorenin in the ovarian hyperstimulation syndrome

Three patients developed severe ovarian hyperstimulation syndrome (OHS) as a complication of ovarian hyperstimulation for in vitro fertilization. These patients presented with ovarian enlargement, vascular volume depletion, pleural effusions, and exudative ascites. A unique feature of the ascites in OHS was the markedly elevated renin concentration, the majority of which was prorenin. We speculate the renin-angiotensin system (RAS) may play a pathophysiologic role in the localized capillary leak that develops in OHS.

The administration of glucocorticoids for the prevention of ovarian hyperstimulation syndrome in in vitro fertilization: a prospective randomized study

OBJECTIVE

To determine if the administration of glucocorticoids reduced the rate of ovarian hyperstimulation syndrome (OHSS) in high-risk patients after ovarian stimulation for in vitro fertilization (IVF).

DESIGN

Prospective randomized study.

PATIENTS

Thirty-one patients who were stimulated with human menopausal gonadotropin (hMG) after pituitary desensitization by gonadotropin-releasing hormone agonist and who developed greater than 20 follicles greater than 12 mm and/or had a serum estradiol (E2) level of greater than 10,000 pmol/L on the day of administration of human chorionic gonadotropin (hCG).

INTERVENTIONS

Patients were randomly divided into two groups. Those who were randomized to receive glucocorticoids (group A) (n = 17) were administered intravenous hydrocortisone, 100 mg, immediately after ultrasound (US)-directed oocyte recovery. Prednisolone, 10 mg three times per day, was given for 5 days starting on the day of oocyte recovery followed by prednisolone 10 mg two times a day for 3 days and 10 mg/d for 2 days. Those in group B (n = 14) did not receive any glucocorticoid treatment. In both groups, luteal support was provided by intramuscular injections of gestone 100 mg/d.

RESULTS

The two groups of patients were comparable in terms of age, duration of infertility, and total dose of hMG used. All had polycystic ovaries on US examination. On the day of hCG administration, the mean number of follicles in the two groups were 26.76 +/- 2.49 and 25.93 +/- 1.44 and the serum E2 concentration 13,404 +/- 710 and 13,915 +/- 901 pmol/L, respectively. There were no significant differences in the number of oocytes collected or in the fertilization, cleavage, and implantation rates in the two groups. The pregnancy rates per initiated cycle were 41.18% and 35.71%, respectively. Seven of the 17 patients (41.2%) who received glucocorticoids developed ovarian hyperstimulation syndrome compared with 6 of the 14 patients (42.9%) who did not receive glucocorticoids.

CONCLUSIONS

Administrations of glucocorticoids to high risk patients did not reduce the rate of OHSS after ovarian stimulation for IVF.

Is it possible to run a successful ovulation induction program based solely on ultrasound monitoring? The importance of endometrial measurements

OBJECTIVE

To attempt the monitoring of ovulation induction solely with ultrasound (US).

DESIGN

Using serial US measurements to monitor ovulation induction using human menopausal gonadotropin and human chorionic gonadotropin (hCG), in comparison with estradiol (E2) concentrations that became available at the end of each cycle.

SETTING

Specialist Reproductive Endocrine Unit.

PATIENTS, PARTICIPANTS

Twenty hypogonadotropic and 29 ultrasonically diagnosed polycystic ovary patients.

MAIN OUTCOME MEASURE

Follicular growth, uterine measurements, endometrial thickness, and serum E2 concentrations.

RESULTS

Follicular growth, uterine measurements, and endometrial thickness correlated strongly with E2 concentrations (P less than 0.0001). The endometrium on the day of hCG administration was significantly thicker (P less than 0.01) in the conception (n = 27) compared with the nonconception cycles (n = 87), whereas no significant difference were observed in serum E2 concentrations. No pregnancy was observed when hCG had been administered when the endometrial thickness was less than or equal to 7 mm. Midluteal endometrial thickness of greater than or equal to 11 mm was found to be a good prognostic factor for detecting early pregnancy (P less than 0.008).

CONCLUSIONS

Serial US examinations used alone have proven to be safe and highly efficient. It also has a unique ability to detect pregnancy in the midluteal phase.