Ovarian hyperstimulation syndrome: an update review

A prospective, randomised, investigator-blind, controlled, clinical study on the clinical efficacy and tolerability of two highly purified hMG preparations administered subcutaneously in women undergoing IVF

The aim of this multicentre, prospective, randomised, investigator blind, controlled clinical trial was to evaluate the clinical efficacy and tolerability of a highly purified human menopausal gonadotrophin (hMG) preparation (Merional-HG) when administered to patients undergoing controlled ovarian stimulation (COS) for in-vitro fertilisation (IVF) procedure enrolled in hospital departments. One hundred fifty-seven patients were randomised in two parallel groups: 78 started COS with Merional-HG and 79 with Menopur. Results of the study showed that both highly purified hMG preparations were equivalent in terms of number of oocytes retrieved (primary endpoint: 8.8 ± 3.9 versus 8.4 ± 3.8, p = 0.54). In the patients treated with Merional-HG, we observed a higher occurrence of mature oocytes (78.3% versus 71.4%, p = 0.005) and a reduced quantity of gonadotrophins administered per cycle (2.556 ± 636 IU versus 2.969 ± 855 IU, p < 0.001). Fertilisation, cleavage, implantation rates and the number of positive β-human chorionic gonadotrophin (hCG; pregnancy) tests and the clinical pregnancy rate were comparable in the two groups. Both treatments were well tolerated. In conclusion, the results of this study support the efficacy and safety of Merional-HG administered subcutaneously for assisted reproduction techniques. Efficiency of Merional-HG appears to be higher due to reduced quantity of drug used and the higher yield of mature oocytes retrieved.

Severe early ovarian hyperstimulation syndrome following GnRH agonist trigger with the addition of 1500 IU hCG

STUDY QUESTION

Is severe early ovarian hyperstimulation syndrome (OHSS) completely prevented with the GnRH agonist trigger and 1500 IU hCG luteal rescue protocol?

SUMMARY ANSWER

Severe early OHSS can occur even after the GnRH agonist trigger and 1500 IU hCG luteal rescue protocol.

WHAT IS KNOWN ALREADY

Prior studies including over 200 women who received the GnRH agonist trigger and 1500 hCG luteal rescue protocol have reported complete prevention of severe early OHSS. Only a few late OHSS cases have been reported and it has been suggested that this protocol can be safely applied to any women under risk.

STUDY DESIGN, SIZE, DURATION

This retrospective cohort study included all women who were at high risk of OHSS and were given the GnRH agonist trigger plus hCG luteal rescue protocol between December 2008 and August 2012 in the two participating centers.

PARTICIPANTS/MATERIALS, SETTING, METHODS

There were 23 women with a mean estradiol level of 4891 ± 2214 pg/ml and a mean number of >12 mm follicles of 20 ± 6 on the day of ovulation triggering. OHSS was categorized according to the Golan criteria.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall 6 of the 23 (26%) women developed severe OHSS. Five women had severe early OHSS requiring ascites drainage and hospitalization and three of these women did not undergo embryo transfer. The number of follicles measuring 10-14 mm on the day of triggering was significantly different between women who developed severe early OHSS and those who did not.

LIMITATIONS, REASONS FOR CAUTION

The small number of women with severe early OHSS may have prevented identification of other significant risk factors.

WIDER IMPLICATIONS OF THE FINDINGS

Although the GnRH agonist plus 1500 IU hCG luteal rescue protocol significantly decreases the risk of severe OHSS, this life threatening complication can still occur in high-risk patients. It would be prudent to avoid hCG luteal rescue and freeze all embryos for future transfer in such women particularly when there are ≥18 follicles with 10-14 mm diameters even with few larger follicles.

Combination of cabergoline and embryo cryopreservation after GnRH agonist triggering prevents OHSS in patients with extremely high estradiol levels--a retrospective study

PURPOSE

Embryo cryopreservation after triggering oocyte maturation with GnRH agonist (GnRHa) in GnRH antagonist protocols has been proposed to prevent ovarian hyperstimulation syndrome (OHSS). However, a small percentage of patients still developed severe OHSS. The purpose of the study was to investigate the efficacy of preventing OHSS in patients at very high risk when cabergoline was given in addition to elective cryopreservation after GnRHa triggering.

METHODS

This is a retrospective observational study. The patients were stimulated with GnRH antagonist protocol. When serum E2 concentration was >6,000 pg/ml and there were more than 20 follicles ≥11 mm on the day of final oocyte maturation, GnRHa was used to trigger oocyte maturation. Cabergoline was given to augment the effect of preventing OHSS. The embryos were electively cryopreserved by vitrification and thawed in subsequent cycles. The primary outcome measure was the incidence of severe OHSS. The secondary outcome measure was the clinical pregnancy rate in the first frozen-thawed embryo transfer cycle.

RESULTS

One hundred and ten patients underwent 110 stimulated cycles were included for analysis. No patients developed moderate/severe OHSS. Mean E2 concentration on the day of final oocyte maturation was 7,873 pg/ml, and an average of 22.7 oocytes was obtained from each patient. One hundred and ten thawing cycles were performed, resulting in 69 clinical pregnancies (62.7 %).

CONCLUSIONS

Combining cabergoline and embryo cryopreservation after GnRHa triggering in GnRH antagonist protocol could prevent OHSS in patients at very high risk.

Effectiveness of GnRH antagonist in the treatment of patients with polycystic ovary syndrome undergoing IVF: a systematic review and meta analysis

OBJECTIVE

To systematically evaluate the effectiveness of the gonadotropin-releasing hormone (GnRH) antagonist on in vitro fertilisation (IVF) in patients with polycystic ovary syndrome (PCOS).

METHODS

Nine types of databases were searched by computer, and nine types of relevant journals were searched manually. Randomized, controlled trials of the effects of the GnRH antagonist and GnRH agonist on IVF-ET treatment in the patients with PCOS were included. A meta-analysis was conducted following a quality evaluation.

RESULTS

Seven published studies (755 patients) were included. A meta-analysis was conducted following a quality evaluation. There were no significant differences in the amount of gonadotropin (Gn) (MD = -2.05; 95% CI: -4.14-0.05], E2 levels on the day of hCG administration (MD = -156.13; 95% CI: -389.91-77.64), the number of oocytes retrieved (MD = -0.38; 95% CI: -2.32-1.56), the clinical pregnancy rate (Peto OR = 1.08; 95% CI: 0.80-1.45), and the abortion rate (Peto OR = 0.91; 95% CI: 0.54-1.53) between the GnRH antagonist group and the GnRH agonist group. The OHSS rate of the GnRH antagonist group was lower than that of the GnRH agonist group, and the difference was statistically significant (Peto OR = 0.36; 95% CI: 0.25-0.52).

CONCLUSIONS

Compared with the GnRH agonist protocol, the GnRH antagonist protocol could significantly reduce the risk of OHSS. The clinical pregnancy rates for these two protocols were similar.

Involvement of the ANGPTs/Tie-2 system in ovarian hyperstimulation syndrome (OHSS)

Ovarian hyperstimulation syndrome (OHSS) is a disorder associated with ovarian stimulation. OHSS features are ovarian enlargement with fluid shifting to the third space. Disturbances in the vasculature are considered the main changes that lead to OHSS. Our aim was to analyze the levels of angiopoietins 1 and 2 (ANGPT1 and 2) and their soluble and membrane receptors (s/mTie-2) in follicular fluid (FF) and in granulosa-lutein cells culture (GLCs) from women at risk of developing OHSS. We also evaluated the effect of ANGPT1 on endothelial cell migration. In ovaries from an OHSS rat model, we analyzed the protein concentration of ANGPTs, their mTie-2 receptor, and platelet-derived growth factor PDGF-B, -D and PDGFR-β. ANGPT1 levels were increased in both FF and GLCs from women at risk of OHSS. Incubation of these FF with an ANGPT1 neutralizing antibody decreased endothelial cell migration. In the ovaries of OHSS rat model, mTie-2 protein levels increased and PDGF-B and -D decreased. In summary, these results suggest that ANGPT1 could be another mediator in the development of OHSS.

GnRH analogues in the prevention of ovarian hyperstimulation syndrome

The GnRH analogue (agonist and antagonist GnRH) changed ovarian stimulation. On the one hand, it improved chances of pregnancy to obtain more oocytes and better embryos. This leads to an ovarian hyper-response, which can be complicated by the ovarian hyperstimulation syndrome (OHSS). On the other hand, the GnRH analogue can prevent the incidence of OHSS: GnRH antagonist protocols, GnRH agonist for triggering final oocyte maturation, either together or separately, coasting, and the GnRH analogue may prove useful for avoiding OHSS in high-risk patients. We review these topics in this article.

Efficacy of different gonadotropin combinations to support ovulation induction in WHO type I anovulation infertility: clinical evidences of human recombinant FSH/human recombinant LH in a 2:1 ratio and highly purified human menopausal gonadotropin stimulation protocols

BACKGROUND

The World Helath Organization (WHO) Group I anovulation, or hypogonadotropic hypogonadism (HH), is characterized by reduced hypothalamic/pituitary activity which results in abnormally low serum FSH and LH levels and negligible estrogen activity.

AIM

To compare the efficacy of human recombinant FSH (r-hFSH) plus human recombinant LH (r-hLH) in a 2:1 ratio with highly purified human menopausal gonadotropin (hMG-HP) urinary extract, containing LH-like activity, in women with HH.

SUBJECTS AND METHODS

This two-arm randomized open-label study included 35 HH women (aged 25-36 yr) attending our Center. Eighteen patients received 150 IU hMG-HP (150 IU FSH + 150 IU LH-like activity) and seventeen received 150IU r-hFSH/75IU rhLH daily for a maximum of 16 days. Ovulation was induced by a single administration of hCG on the day after the last hMG-HP or r-hFSH/r-hLH.

RESULTS

The primary efficacy endpoint was ovulation induction as measured by follicle ≥17 mm, pre-ovulatory estradiol (E 2 ) ≥400 pmol/l and mid-luteal phase progesterone (P 4 ) ≥25 nmol/l. Secondary efficacy endpoints included E 2 levels/follicle at mid-cycle, number of follicles at mid-cycle and pregnancy rate (PR). Following a total of 70 cycles, 70% of r-hFSH/r-hLH treated patients met the primary endpoint vs 88% in hMG-HP group (p=0.11). However, PR in r-hFSH/r-hLH group was 55.6% compared to 23.3% in hMG-HP group (p=0.01).

CONCLUSIONS

The primary endpoint achievement did not correlate with PR. This study has shown the superiority of LH compared to hCG in supporting FSH-induced follicular development in HH women.

Can dopamine agonist at a low dose reduce ovarian hyperstimulation syndrome in women at risk undergoing ICSI treatment cycles? A randomized controlled study

OBJECTIVE

Dopamine agonists were proposed as a preventive strategy for severe ovarian. The aim of this randomized controlled study is to evaluate the role of dopamine agonist at lower doses (0.25mg) as a preventive strategy of severe hyperstimulation syndrome (OHSS) in women at high risk in IVF/ICSI treatment cycles.

STUDY DESIGN

Two hundred women at risk to develop OHSS undergoing IVF/ICSI treatment cycle were included; the study group received 0.25mg of cabergoline for 8 days from the day of HCG administration versus no treatment for the prevention of OHSS. Reduction of the incidence OHSS was the primary outcome.

RESULTS

The overall incidence of OHSS was significantly reduced, almost 50%, in cabergoline group in comparison with control group (RR: 0.5, 95% CI: 0.29-0.83), with absolute risk reduction following cabergoline administration 11% (ARR: 0.11, 95% CI: 1.09-20.91). The corresponding number needed to treat (NNT) was 9.

CONCLUSION

Prophylactic treatment with the dopamine agonist, cabergoline, at lower doses (0.25mg) reduces the incidence of OHSS in women at high risk undergoing IVF/ICSI treatment.

A prospective study of GnRH long agonist versus flexible GnRH antagonist protocol in PCOS: Indian experience

CONTEXT:

Pathogenesis of uterine synechia remains unsolved, the causal relationship between synechia and infertility is not clearly established.

AIMS:

To evaluate the rabbit as an experimental model for Asherman's syndrome using the endometrial curettage as trigger mechanism then to evaluate its impact on fertility.

SETTINGS AND DESIGN:

Experimental study

MATERIALS AND METHODS:

13 female rabbits. All submitted traumatic endometrial curettage. Animals of Group 1 (n = 7) were sacrificed at various times following surgery (day 7, 15 and 30), animals of Group 2 (n = 6) were bred and sacrificed during pregnancy. Main outcome were synechia occurring, number of implanted fetus, lumen surface/ global horn perimeter ratio (LS-GHP ratio) and epithelium thickness.

STATISTICAL ANALYSIS:

Means were compared using Student ‘t’ test (P < 0.05 was considered significant). Number of implantation sites of two horns were compared with the Wilcoxon test.

RESULTS:

No synechia have been observed. Examinations at Day 7, 15 and 30 demonstrate a complete regeneration of endometrium. We observed a significant diminished LS-GHP ratio at day 7 (0.042 ± 0.004 vs 0.074 ± 0.002 mm; P = 0.013) with a higher simple columnar epithelium compared to control (16.6 ± 3.39 vs 10.98 ± 1.7; P = 0.001). We observed a diminished ovum implantation in traumatized horns, even if it was not statistically significant.

CONCLUSION:

Even if no intrauterine adhesion were observed, this model represents a pathogenesis condition in the rabbit similar to intrauterine adhesions observed in the human with negative impact on implantation.

Treatment of ovarian hyperstimulation syndrome using gonadotropin releasing hormone antagonist: a pilot study

OBJECTIVE

This novel study describes an effective outpatient treatment for ovarian hyperstimulation syndrome (OHSS) that results in rapid normalization of symptoms.

STUDY DESIGN

A total of twenty-seven infertile women undergoing assisted reproductive technique with early-onset OHSS were enrolled in this non-randomized clinical trial in an academic infertility center. In all patients, after complete desensitization with long-term protocol ovarian stimulation with gonadotropins was commenced. Final oocyte maturation was triggered with human chorionic gonadotrophin. Oocytes were collected 36-38 h later using transvaginal-guided follicle aspiration under general anaesthesia. All embryos were frozen and study group patients received two consecutive doses of GnRH antagonist (Cetrotide) and the control group received daily dose of cabergoline for a week.

RESULTS

The research revealed that moderate and severe OHSS, hospitalization or acute care for OHSS and ascites tap were significantly lower in the antagonist (Cetrotide) group. The Patients' satisfaction with Cetrotide was noticeable. No side effect was reported in either group.

CONCLUSION

GnRH antagonists seem to be an effective outpatient treatment with rapid onset activity and minimal side effects for the management of early OHSS.

A case of ovarian hyperstimulation syndrome following a spontaneous complete hydatidiform molar pregnancy

INTRODUCTION

To present a rare case of ovarian hyperstimulation syndrome (OHSS) following a spontaneous complete hydatidiform molar (CHM) pregnancy.

CASE

A 38-year-old woman underwent vacuum curettage for a CHM pregnancy. Seven days later, she was admitted to our hospital with the symptoms of OHSS. Transvaginal ultrasonography demonstrated enlarged multicystic ovaries, marked ascites and large pleural effusions that required abdominocentesis and thoracocentesis, respectively. She was treated with intravenous fluid, exogenous colloid supplementation, prophylaxis for deep vein thrombosis, and drainage of the ascites and bilateral pleural effusions. She recovered by day 14 of admission.

CONCLUSION

OHSS may develop in older women who undergo treatment for CHM pregnancies. Serious complications may develop rapidly and therefore the prompt diagnosis of OHSS is very important.

VEGF antagonist for the prevention of ovarian hyperstimulation syndrome: Current status

Ovarian Hyperstimulation Syndrome (OHSS) an iatrogenic and potentially life-threatening complication resulting from an exaggerated response to ovulation induction with gonadotropins during assisted reproductive technologies, is a self-limiting disorder with a broad spectrum of clinical manifestations related to increased capillary permeability and fluid retention brought about by many biochemical mediators especially vascular endothelium growth factor (VEGF), playing a pivotal role in its pathophysiology. Although various strategies had been proposed and tried to prevent this serious complication none was found to be completely effective. With the current knowledge and understanding of the causative molecule i.e. VEGF in the pathogenesis of OHSS, pharmacologic tools targeting this member of the family of heparin binding proteins, seems promising. Antagonizing and blocking VEGF action by dopamine agonists especially Cabergoline has shown to be a valid alternative to overcome the changes induced by the gonadotropins. Delaying embryo transfer with embryo cryopreservation definitely reduces the incidence of OHSS but not the early OHSS. In-vitro maturation of oocytes a major breakthrough in the field of ART although totally eliminates the risk of OHSS is highly labor intensive and cannot routinely carried in all cycles. Thus the newer drugs, mainly the dopamine agonists in the light of the new pathogenic and pharmacological evidence, should definitely be considered for prevention of both early and late OHSS.

Early initiation of gonadotropin-releasing hormone antagonist in polycystic ovarian syndrome patients undergoing assisted reproduction: randomized controlled trial ISRCTN69937179

PURPOSE

To compare the implantation rates in two groups of women with Polycystic Ovary Syndrome (PCOS) after embryo transfer based on the initiation time of GnRH antagonist. Secondary outcome measures included clinical pregnancy, delivery and miscarriage rates.

METHODS

This is a prospective, randomized trial in which 140 PCOS patients underwent ICSI, with 122 having ET performed. GnRH-antagonist was started on day 1 of stimulation in 69 patients (Group 1) or day 5 in 71 patients (Group 2).

RESULTS

The overall implantation rate in Group 1 (46.2 %) was clinically higher than Group 2 (35.5 %), although not statistically significant (p = 0.075). For blastocysts transfer, the implantation rate in Group 1 was 55.1 %, compared to 40.4 % in Group 2 (p = 0.051). There was a clinically, but not statistically, higher clinical pregnancy rate (68.3 % vs. 56.5 %) and delivery rate (60.0 % vs. 53.2 %) per transfer in Group 1 compared to Group 2, respectively. There was a statistically significant lower biochemical pregnancy rate in Group 1 (2.4 %) compared to Group 2 (18.6 %) [p = 0.015]. There was no difference in miscarriage rates between the two groups.

CONCLUSION

Our data suggest that early initiation of GnRH antagonist on day 1 of ovarian stimulation in PCOS patients undergoing ICSI-ET may improve implantation rates, especially after blastocyst transfer.

GnRH antagonist rescue in high responders at risk for OHSS results in excellent assisted reproduction outcomes

Gonadotrophin-releasing hormone (GnRH) antagonist rescue is performed by replacing a GnRH agonist with a GnRH antagonist in patients with rapidly rising serum oestradiol who are at risk of ovarian hyperstimulation syndrome (OHSS) during stimulation. It results in a rapid reduction in serum oestradiol, allowing for the avoidance of cycle cancellation and the continuation of exogenous gonadotrophin administration. A total of 387 patients who underwent GnRH antagonist rescue for ovarian hyperresponse were compared with 271 patients who did not receive GnRH antagonist rescue and had oestradiol concentrations >4000 pg/ml on the day of human chorionic gonadotrophin (HCG) administration. GnRH antagonist rescue decreased the mean oestradiol concentration by 35% on the first day of use. There was no difference in oocyte maturity (82% versus 83%) or fertilization rate (69% versus 67%) between the antagonist rescue and comparison groups, respectively. The percentage of high-grade embryos on day 3 and the blastocyst development rate were also similar between groups. The live-birth rate was 41.9% in the antagonist rescue group and 36.9% in the comparison group. GnRH antagonist rescue enabled cycle completion with high live-birth rates in patients at risk for OHSS. GnRH antagonist was associated with high oocyte quality, blastocyst development and pregnancy. Gonadotrophin-releasing hormone (GnRH) antagonist rescue is a protocol to reduce the risk of ovarian hyperstimulation syndrome (OHSS) in assisted reproduction treatment. Patients who have a hyperresponse to medication during their treatment cycle have their GnRH agonist discontinued and a GnRH antagonist started in its place. This causes a rapid reduction in oestrogen concentrations and allows for the continuation of stimulation medication. We evaluated the effectiveness of this protocol by comparing patients who had GnRH antagonist rescue against high-responding patients who did not receive GnRH antagonist rescue. GnRH antagonist rescue resulted in a 35% reduction in oestrogen concentration and only a 1.5% cycle cancellation rate. There were no differences in oocyte maturity or fertilization between the two groups. There were no differences in the quality of day-3 and day-5 embryos between the two groups. The live birth rate was 41.9% in the antagonist rescue group and 36.9% in the comparison group. GnRH antagonist rescue reduced serum oestradiol concentrations and enabled cycle completion with high live-birth rates in patients at risk for OHSS. GnRH antagonist was associated with high oocyte quality, blastocyst development and pregnancy.

Outpatient management of severe early OHSS by administration of GnRH antagonist in the luteal phase: an observational cohort study

BACKGROUND

Management of established severe OHSS requires prolonged hospitalization, occasionally in intensive care units, accompanied by multiple ascites punctures, correction of intravascular fluid volume and electrolyte imbalance. The aim of the present study was to evaluate whether it is feasible to manage women with severe OHSS as outpatients by treating them with GnRH antagonists in the luteal phase.

METHODS

This is a single-centre, prospective, observational, cohort study. Forty patients diagnosed with severe OHSS, five days post oocyte retrieval, were managed as outpatients after administration of GnRH antagonist (0.25 mg) daily from days 5 to 8 post oocyte retrieval, combined with cryopreservation of all embryos. The primary outcome measure was the proportion of patients with severe OHSS, in whom outpatient management was not feasible.

RESULTS

11.3% (95% CI 8.3%-15.0%) of patients (40/353) developed severe early OHSS. None of the 40 patients required hospitalization following luteal antagonist administration and embryo cryopreservation. Ovarian volume, ascites, hematocrit, WBC, serum oestradiol and progesterone decreased significantly (P < 0.001) by the end of the monitoring period, indicating rapid resolution of severe OHSS.

CONCLUSIONS

The current study suggests, for the first time, that successful outpatient management of severe OHSS with antagonist treatment in the luteal phase is feasible and is associated with rapid regression of the syndrome, challenging the dogma of inpatient management. The proposed management is a flexible approach that minimizes unnecessary embryo transfer cancellations in the majority (88.7%) of high risk for OHSS patients.

Effectiveness of GnRH antagonist multiple dose protocol applied during early and late follicular phase compared with GnRH agonist long protocol in non-obese and obese patients with polycystic ovary syndrome undergoing IVF/ICSI

Objective

To evaluate the effectiveness of GnRH antagonist multiple dose protocol applied during early and late follicular phase (MDP-EL) in comparison with standard GnRH agonist luteal long protocol (LP) in each non-obese and obese polycystic ovary syndrome (PCOS) women undergoing IVF.

Methods

Two hundred eleven infertile women with PCOS were recruited and randomized to undergo either GnRH antagonist MDP-EL (antagonist group) or standard GnRH agonist luteal LP (agonist group). IVF cycle outcomes were compared between the two groups.

Results

Total dose and days of recombinant human follicle stimulating hormone (rhFSH) administered were significantly fewer in the antagonist group than in the agonist group. Incidence of severe ovarian hyperstimulation syndrome was significantly lower in the antagonist group. However, IVF and pregnancy outcomes were similar in the two groups. When all subjects were divided into non-obese and obese subgroups, in non-obese PCOS subgroup, IVF and pregnancy outcomes were comparable in the antagonist and agonist groups but total dose and days of rhFSH were also significantly fewer in the antagonist group. Similar findings were also observed in obese PCOS subgroup.

Conclusion

GnRH antagonist MDP-EL is at least as effective as GnRH agonist LP and may be a more patient-friendly alternative in controlled ovarian stimulation for PCOS patients undergoing IVF, independent of body mass index.

The diagnosis and management of ovarian hyperstimulation syndrome

OBJECTIVE

To review the clinical aspects of ovarian hyperstimulation syndrome and provide recommendations on its diagnosis and clinical management.

OUTCOMES

These guidelines will assist in the early recognition and management of ovarian hyperstimulation. Early recognition and prompt systematic supportive care will help avert poor outcomes.

EVIDENCE

Medline, Embase, and the Cochrane database were searched for relevant articles, using the key words "ovarian hyperstimulation syndrome" and "gonadotropins," and guidelines created by other professional societies were reviewed.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care. Recommendations for practice were ranked according to the method described in that report (Table 1).

RECOMMENDATIONS

1. Once the diagnosis of ovarian hyperstimulation syndrome is made, disease severity should be classified as mild, moderate, severe, or critical. (III-B) 2. The physician prescribing gonadotropins should inform each woman of her personal risk for ovarian hyperstimulation syndrome. (III-A) 3. In areas where patients do not have ready access to physicians familiar with the diagnosis and management of ovarian hyperstimulation syndrome, the physician prescribing gonadotropins should ensure that women are made aware that they should contact a physician or a member of the team within the hospital unit who has relevant experience, should the need arise. (III-B) 4. Outpatient management is recommended for women with mild and moderate ovarian hyperstimulation syndrome. If outpatient management for more severe ovarian hyperstimulation syndrome is to be undertaken, the physician should ensure that the woman is capable of adhering to clinical instructions and that there is a system in place to assess her status every 1 to 2 days. (III-A) 5. Paracentesis should be performed in admitted patients with tense ascites to alleviate their discomfort. (II-2B) 6. Outpatient culdocentesis should be considered for the prevention of disease progression in moderate or severe ovarian hyperstimulation syndrome. (II-2B) 7. Women with severe and critical ovarian hyperstimulation syndrome should be admitted to hospital for intravenous hydration and observation. (III-A) 8. Intravenous hydration should be initiated with a crystalloid solution to prevent hemoconcentration and provide adequate end-organ perfusion. If end-organ perfusion is not maintained with a crystalloid solution, an alternate colloid solution should be administered. (II-2B) 9. Pain relief in admitted patients should be managed with acetaminophen and/or opioid analgesics. (III-B) Non-steroidal anti-inflammatory drugs with antiplatelet properties should not be used. (III-B) 10. Women with severe ovarian hyperstimulation syndrome should be considered for treatment with prophylactic doses of anticoagulants. (II-2B) 11. Critical ovarian hyperstimulation syndrome should be managed by a multidisciplinary team, according to the end organ affected. (III-C).

Cabergoline for preventing ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a complication resulting from administration of human chorionic gonadotrophin (hCG) in assisted reproduction technology (ART) treatment. Most case are mild, but forms of moderate or severe OHSS appear in 3% to 8% of in vitro fertilisation (IVF) cycles. Recently, the dopamine agonist cabergoline has been introduced as a secondary prevention intervention for OHSS in women at high risk of OHSS who are undergoing ART treatment.

OBJECTIVES

To assess the effectiveness and safety of cabergoline in preventing ovarian hyperstimulation syndrome (OHSS) in high-risk women undergoing ART treatment.

SEARCH METHODS

Major medical databases (Cochrane Menstrual Disorders and Subfertility Group Specialised Register of trials, CENTRAL (The Cochrane Library), MEDLINE, EMBASE and PsycINFO) were systematically searched for randomised controlled trials (RCTs) assessing the effect of cabergoline in preventing OHSS. Databases were searched up to September 2011. Registers of clinical trials, abstracts of scientific meetings and reference lists of included studies were searched. No language restrictions were applied.

SELECTION CRITERIA

RCTs which compared cabergoline with placebo, no treatment or another intervention for preventing OHSS in high-risk women were considered for inclusion. Primary outcome measures included incidence of moderate or severe OHSS and live birth rate. Secondary endpoints were clinical pregnancy rate, multiple pregnancy rate, miscarriage rate and any other adverse effects of the treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently screened titles, abstracts and the full text of publications; extracted data; and assessed risk of bias. Any disagreements were resolved by consensus. Pooled results were reported as odds ratio (OR) and 95% confidence interval (95% CI) by the Mantel-Haenszel method.

MAIN RESULTS

Only two trials involving 230 women met the inclusion criteria. Both studies had a moderate risk of bias. Oral cabergoline, 0.5 mg daily, was given as an intervention and compared with a matched placebo. A statistically significant reduction in OHSS was observed in the cabergoline treated group (OR 0.40, 95% CI 0.20 to 0.77; 2 RCTs, 230 women) with a number needed to treat (NTT) of 7. There was a statistically significant difference in the incidence of moderate OHSS, favouring cabergoline (OR 0.38, 95% CI 0.19 to 0.78; 2 RCTs, 230 women) but not in severe OHSS (OR 0.77, 95% CI 0.24 to 2.45; 2 RCTs, 230 women). There was no significant difference in the clinical pregnancy rate (OR 0.94, 95% CI 0.56 to 1.59; 2 RCTs, 230 women), miscarriage rate (OR 0.31, 95% CI 0.03 to 3.07; 1 RCT, 163 women) or any other adverse effects of the treatment (OR 2.07, 95% CI 0.56 to 7.70; 1 RCT, 67 women). However, no data on multiple pregnancy rate or live birth rate were reported in either trial.

AUTHORS' CONCLUSIONS

Cabergoline appears to reduce the risk of OHSS in high-risk women, especially for moderate OHSS. The use of cabergoline does not affect the pregnancy outcome (clinical pregnancy rate, miscarriage rate), nor is there an increased risk of adverse events. Further research should consider the risk of administering cabergoline and the comparison between cabergoline and established treatments (such as intravenous albumin and coasting). Large, well-designed and well-executed RCTs that involve more clinical endpoints are necessary to further evaluate the role of cabergoline in OHSS prevention.

A randomized assessor-blind trial comparing highly purified hMG and recombinant FSH in a GnRH antagonist cycle with compulsory single-blastocyst transfer

OBJECTIVE

To compare the efficacy and safety of highly purified menotropin (hphMG) and recombinant FSH (rFSH) for controlled ovarian stimulation in a GnRH antagonist cycle with compulsory single-blastocyst transfer.

DESIGN

Randomized, open-label, assessor-blind, parallel groups, multicenter, noninferiority trial.

SETTING

Twenty-five infertility centers in seven countries.

PATIENT(S)

Seven hundred forty-nine women.

INTERVENTION(S)

Controlled ovarian stimulation with hphMG or rFSH in a GnRH antagonist cycle with compulsory single-blastocyst transfer on day 5 in one fresh or subsequent frozen blastocyst replacement in natural cycles initiated within 1 year of each patient's start of treatment.

MAIN OUTCOME MEASURE(S)

Ongoing pregnancy (primary end point) and live birth rates, as well as pharmacodynamic parameters.

RESULT(S)

The ongoing pregnancy rate after a fresh cycle was 30% with hphMG versus 27% with rFSH for the per-protocol (PP) population and 29% versus 27% for the intention-to-treat (ITT) population. Noninferiority of hphMG compared to rFSH was established. Considering frozen cycles initiated within 1 year, the cumulative live birth rate for a single stimulation cycle was 40% and 38% for women treated with hphMG and rFSH, respectively (both PP and ITT). Significant differences in pharmacodynamic end points were found between the two gonadotropin preparations.

CONCLUSION(S)

Highly purified hMG is at least as effective as rFSH in GnRH antagonist cycles with compulsory single-blastocyst transfer.

CLINICAL TRIAL REGISTRATION NUMBER

NCT00884221.

Comparison of cabergoline and intravenous albumin in the prevention of ovarian hyperstimulation syndrome: a randomized clinical trial

PURPOSE

To compare the efficacy of cabergoline (Cb2) and intravenous human albumin (HA) in the prevention of ovarian hyperstimulation syndrome.

METHODS

In this randomized controlled trial study, 138 women who were at high risk for developing OHSS were randomly allocated into two groups. In Group one, 20 gr of HA 20% was infused over 1 h. Group two received 0.5 mg per day of Cb2 orally for 7 days, starting on oocyte pickup day. All patients were visited seven and 14 days after oocyte retrieval to determine early clinical or ultrasound evidence of OHSS.

RESULTS

Moderate OHSS was observed in 33 versus 14 cases in the HA and Cb2 groups, respectively, which was significantly different. The number of severe OHSS cases in the HA group was significantly higher than in the Cb2 group (P < 0.001).

CONCLUSIONS

Prophylactic oral low dose cabergoline was more effective and less costly than intravenous human albumin in the prevention of OHSS in high-risk patients.

Ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication of assisted reproduction technology. The syndrome is characterized by cystic enlargement of the ovaries and a fluid shift from the intravascular to the third space due to increased capillary permeability and ovarian neoangiogenesis. Its occurrence is dependent on the administration of human chorionic gonadotrophin (hCG). β-hCG and its analogs, estrogen, estradiol, prolactin, histamine and prostaglandins have all been implicated in OHSS but now it is increasingly better understood that the vasoactivesubstances such as interleukins, tumor necrosis factor-α, endothelin-1, and vascular endothelial growth factor (VEGF) secreted by the ovaries have been implicated in increasing vascular permeability. Enlargement of the ovaries causes abdominal pain, nausea and vomiting. Leakage of fluid from follicles, increased capillary permeability leading to third spacing (due to the release of vasoactive substances), or frank rupture of follicles can all cause ascites. Due to leakage of fluid through the impaired blood vessels both within and outside the ovary there is massive fluid-shift from the intra-vescular bed to the third compartment results in intravascular hypovolemia with concomitant development of edema, ascites, hydrothorax and/or hydropericardium. Low-dose gonadotrophin protocols have been implemented to reduce the risks of fertility treatment in polycystic ovary syndrome patients. Prophylactic albumin administration may interrupt the development of OHSS by increasing the plasma oncotic pressure and binding mediators of ovarian origin. OHSS is significantly lower in an antagonist protocol than in an agonist protocol. Cabergoline inhibits partially the VEGF receptor 2 phosphorylation levels and associated vascular permeability without affecting luteal angiogenesis reduces the 'early' (within the first 9 days after hCG) onset of OHSS. To prevent thrombosis, subcutaneous heparin 5000-7500 U/d is begun on the first day of admission. These patients need a hospital ward where the clinical picture is well understood and the personnel have expertise in its treatment and follow-up. Admission to an intensive care unit is necessary when critical OHSS develops.

Ovarian hyperstimulation syndrome is correlated with a reduction of soluble VEGF receptor protein level and a higher amount of VEGF-A

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a potentially life-threatening condition associated with increased vascular permeability. The vascular endothelial growth factor (VEGF) system and its receptors have been identified as the main angiogenic factors responsible for increased capillary permeability and are therefore discussed as crucial for the occurrence of OHSS. Recently, a number of soluble receptors for the VEGFs have been detected (sVEGF-Rs) and it has been shown that these sVEGF-Rs compete with the membrane-standing VEGF-R to bind VEGFs.

METHODS

We analyzed the serum levels of soluble VEGF-R1, -R2 and -R3 in 34 patients suffering from OHSS and in 34 controls without this disease. In a subgroup analysis, we correlated the severity of the OHSS with the detected amounts of VEGF-R1, -R2 and -R3. In addition, we determined the amount of total VEGF-A in the samples.

RESULTS

All the three soluble VEGF receptors tended to be higher in the control group compared with that in the OHSS group but this difference only reached significance for sVEGF-R2 (mean ± SEM: 15.5 ± 0.6 versus 13.8 ± 0.5 ng/ml, respectively, P< 0.05). In the subgroup analysis, sVEGF-R2 levels decreased as the severity of OHSS increased (OHSS-I: 16.8 ± 1.9 ng/ml and OHSS-III: 12.7 ± 1.0 ng/ml, P< 0.05) Moreover, the serum levels of total VEGF-A were higher in the OHSS group than those in the controls (537.7 ± 38.9 versus 351 ± 53.4 pg/ml, respectively P< 0.05).

CONCLUSIONS

We propose that VEGF-A plays a role in the occurrence of OHSS, that the amount of biologically available VEGF-A is modulated by sVEGF-Rs and that different combinations of VEGF-A and sVEGF-R levels might contribute to the severity of OHSS.

Update on management of ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) is a relatively common complication of ovarian stimulation and can be life threatening. The pathophysiology of OHSS is characterized by increased capillary permeability, leading to leakage of fluid from the vascular compartment, with third-space fluid accumulation and intravascular dehydration. The increased intra-abdominal pressure indicated that OHSS may be considered a compartment syndrome. Vascular endothelial growth factor, also known as vascular permeability factor, has emerged as one of the mediators intrinsic to the development of OHSS. Conventional management is focused on supportive care until the spontaneous resolution of the condition. The standard of care for treatment-monitoring of appropriate clinical parameters, fluid balance management, thrombosis prophylaxis, and ascites treatment-should prevent severe morbidity in most cases. This review will cover inpatient and outpatient management. The potential therapeutic approach targeting the vascular endothelial growth factor system will be discussed.

Symptomatic isolated pleural effusion as an atypical presentation of ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) presents in ~33% of ovarian stimulation cycles with clinical manifestations varying from mild to severe. Its pathogenesis is unknown. Pleural effusion is reported in ~10% of severe OHSS cases and is usually associated with marked ascites. The isolated finding of pleural effusions without ascites, as the main presenting symptom of OHSS is not frequently reported and its pathogenesis is also unknown. We describe two unusual cases of OHSS where dyspnea secondary to unilateral pleural effusion was the only presenting symptom. By reporting our experience, we would like to heighten physicians' awareness in detecting these cases early, as it is our belief that the incidence of pleural effusion in the absence of most commonly recognized risk factors for OHSS may be underestimated and may significantly compromise the health of the patient if treatment is not initiated in a reasonable amount of time.

Severe ovarian hyperstimulation syndrome leading to ICU admission

Severe ovarian hyperstimulation is a rare complication of ovulation induction therapy. In this report, we are presenting a case of 33-year female, who required intensive care unit admission due to respiratory failure secondary to massive pleural effusion and ascites. With the positive history of in vitro fertilization, the patient was diagnosed to have severe ovarian hyperstimulation syndrome. Besides the medical treatment, abdominal paracentesis for the drainage of massive ascites and tube thoracostomy were performed, resulting in gradual improvement.

Coasting (withholding gonadotrophins) for preventing ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic and potentially life threatening condition resulting from excessive ovarian stimulation. Reported incidence varies from 1% to 10% of in vitro fertilization (IVF) cycles. The factors contributing to OHSS have not been completely explained. The release of vasoactive substances secreted by the ovaries under human chorionic gonadotrophin (hCG) stimulation may play a key role in triggering this syndrome. This condition is characterised by a massive shift of fluid from the intra-vascular compartment to the third space resulting in profound intra-vascular depletion and haemoconcentration.

OBJECTIVES

To assess the effect of withholding gonadotrophins (coasting) on the prevention of ovarian hyperstimulation syndrome in assisted reproduction cycles.

SEARCH STRATEGY

For the update of this review we searched the Cochrane Menstrual Disorders and Subfertility Review Group Trials Register (July 2010), CENTRAL (inception to July 2010), MEDLINE (PubMed) (inception to July 2010), and EMBASE (inception to July 2010) for randomised controlled trials (RCTs) in which coasting was used to prevent OHSS.

SELECTION CRITERIA

Only randomised controlled trials (RCTs) in which coasting was used to prevent OHSS were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials and extracted data. Disagreements were resolved by discussion. Study authors were contacted to request additional information or missing data. The intervention comparisons were coasting versus early unilateral follicular aspiration (EUFA), no coasting or other interventions. Statistical analysis was performed in accordance with the Cochrane Menstrual Disorders and Subfertility Group guidelines.

MAIN RESULTS

This updated review identified 16 studies of which four met the inclusion criteria. There was no evidence of a difference in the incidence of moderate and severe OHSS (odds ratio (OR) 0.53, 95% CI 0.23 to 1.23), live birth (OR 0.48, 95% CI 0.14 to 1.62; P = 0.24) or in the clinical pregnancy rate (OR 0.69, 95% CI 0.44 to 1.08) between the groups. Significantly fewer oocytes were retrieved in coasting groups compared with GnRHa (OR -2.44, 95% CI -4.30 to -0.58; P = 0.01) or no coasting (OR -3.92, 95% CI -4.47 to -3.37; P < 0.0001). Data for coasting versus EUFA were not pooled for number of oocytes retrieved due to heterogeneity (I(2) = 87%).

AUTHORS' CONCLUSIONS

There was no evidence to suggest a benefit of using coasting to prevent OHSS compared with no coasting or other interventions.

Infiltrative lung diseases in pregnancy

Pregnancy may affect the diagnosis, management, and outcome of infiltrative lung disease (ILD). Conversely, ILD may affect pregnancy. ILD may occur as a result of drugs administered commonly or specifically during pregnancy. Most ILDs predominate in patients older than 40 years and are thus rare in pregnant women. During pregnancy ILD may arise de novo and preexisting ILD may be exacerbated or significantly worsened. Some ILDs generally do not alter the management of pregnancy, labor, or delivery. Preexisting ILD no longer contraindicates pregnancy systematically, but thorough evaluation of ILD before pregnancy is required to identify potential contraindications and adapt monitoring.

Divergent effects of the 677C>T mutation of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene on ovarian responsiveness and anti-Müllerian hormone concentrations

OBJECTIVE

To investigate the influence of the 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C>T mutation on serum anti-Müllerian hormone (AMH) concentrations and on the numbers of oocytes retrieved (NOR) following controlled ovarian hyperstimulation (COH).

DESIGN

Prospective cohort study.

SETTING

University-based infertility clinic.

PATIENT(S)

Two hundred and seventy women undergoing COH for IVF with or without intracytoplasmic sperm injection.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

AMH levels were determined from blood samples collected after 10 days of GnRH superagonist treatment and before COH. The MTHFR 677C>T genotype was characterized by a TaqMan 5' nuclease assay.

RESULT(S)

AMH serum concentrations correlated significantly with the NOR in all individuals studied. Average (±SD) AMH levels of TT carriers (2.85±2.23 ng/mL) were significantly higher than those of homozygous CC (1.91±1.59 ng/mL) or heterozygous CT individuals (2.23±1.74 ng/mL). When evaluated by multiple regression analysis, AMH had a significant positive effect on NOR, whereas age and MTHFR 677TT genotype had significant negative effects.

CONCLUSION(S)

The MTHFR 677TT genotype is associated with higher serum AMH concentrations and has a negative effect on NOR. This apparent paradox might be resolved in light of recent findings describing a negative feedback function of AMH in the coordination of follicle development.

Administration of a gonadotropin-releasing hormone agonist affects corpus luteum vascular stability and development and induces luteal apoptosis in a rat model of ovarian hyperstimulation syndrome

Ovarian hyperstimulation syndrome (OHSS) is a complication of ovarian stimulation with gonadotropins followed by the administration of human chorionic gonadotropin (hCG) to trigger the final steps of oocyte maturation. Gonadotropin-releasing hormone (GnRH) analogs are thought to be effective in preventing this complication and a clinical trial has found a lower incidence of OHSS in patients treated with these molecules. Our aim was to analyze the in vivo effect of a GnRH-I agonist on corpus luteum development and regression, ANGPT-1, ANGPT-2 and Tie-2 protein expression and luteal blood vessel stabilization, the expression of the steroidogenic acute regulatory protein (StAR) and the cytochrome P450 side-chain cleavage enzyme (P450scc) and cell proliferation, in ovaries from an OHSS rat model. To this end immature female Sprague-Dawley rats were hyperstimulated and treated with a GnRH-I agonist from the start of pregnant mare serum gonadotropin (PMSG) administration until the day of hCG injection for 5 consecutive days. Blood and tissue samples were collected 48h after hCG injection. Vascular endothelial growth factor VEGF levels were evaluated in the peritoneal fluid by ELISA. Serum progesterone and estradiol were measured by RIA. Histological features of sectioned ovaries were assessed in hematoxylin and eosin (H&E) stained slides. Luteal blood vessel stability, cell proliferation and apoptosis were assessed by immunohistochemistry for SMCA, PCNA, and TUNEL, respectively. P450scc, StAR, FLK-1, ANGPT-1, ANGPT-2, Tie-2 and PCNA protein levels were evaluated by Western blot from dissected corpora lutea (CL). The treatment with the GnRH-I agonist significantly decreased serum progesterone and estradiol levels as well as P450scc and StAR protein expression in the untreated OHSS group. In addition, the agonist significantly decreased the number of CL in the OHSS group, as compared with the untreated OHSS group. In the OHSS group, the area of periendothelial cells in the CL was larger than that of the control group. However, the treatment with the GnRH-I agonist significantly reduced the area of periendothelial cells in the CL in the OHSS group. The luteal levels of ANGPT-1 and its receptor Tie-2 significantly increased in the OHSS group when compared with the control group. Conversely, the administration of the GnRH-I agonist significantly decreased the levels of these factors in the CL from the OHSS group, as compared with the untreated OHSS group. In addition, the treatment with the GnRH-I agonist reduced the diameter of CL and decreased CL cell proliferation as compared with that observed in the untreated OHSS group. Finally, the GnRH-I agonist increased apoptosis in the CL from the OHSS group. In conclusion, these results show that GnRH-I agonist exerts diverse actions on the CL from a rat OHSS model. The decrease in P450scc, StAR, ANGPT-1 and Tie-2 expression, blood vessel stability and luteal proliferation leads to CL regression in the ovaries from OHSS rats. Moreover, our results suggest that the downregulation of ANGPT-1 and its receptor is a possible mechanism whereby GnRH-I agonists could prevent early OHSS.

Combined metformin and clomiphene citrate versus highly purified FSH for ovulation induction in clomiphene-resistant PCOS women: a randomised controlled trial

AIM

To compare the effect of combined metformin-clomiphene citrate (CC) with highly purified urinary FSH (HP-uFSH) for ovulation induction in CC-resistant women with polycystic ovary syndrome (PCOS).

METHODS

One-hundred fifty-three anovulatory women with CC-resistant PCOS were selected in this randomised controlled trial. Patients received combined metformin-CC (n=75, 205 cycles) or HP-uFSH (n=78, 186 cycles) for three cycles. Outcome measures were; Ovulation rate, number of growing and mature follicles, serum E2, serum P, endometrial thickness, pregnancy and miscarriage rates.

RESULTS

The ovulation rate per cycle was significantly higher in the HP-uFSH group (83.8% vs. 62%, p=0.01). The number of follicles ≥ 12 mm ≥ 14 mm and ≥ 18 mm on the hCG day was significantly greater in the HP-uFSH group (p=0.01, p=0.02 and p=0.03, respectively). Pregnancy occurred in 23/205 cycles (11.2%) in combined metformin-CC group and 40/186 cycles (21.5%) in the HP-uFSH group; the difference was statistically significant (p=0.02). Two patients in the HP-uFSH group suffered mild OHSS.

CONCLUSIONS

Combined metformin-CC resulted in modest ovulation and pregnancy rates without side effects. It is logical to offer this first for CC-resistant PCOS women before resorting to more expensive alternatives especially in developing communities where economic aspects of therapy are important.

Intra-venous fluids for the prevention of severe ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is a serious and potentially fatal complication of ovarian stimulation, which affects 1% to 14% of all in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) cycles. A number of clinical studies with conflicting results have reported on the use of intravenous fluids such as albumin, hydroxyethyl starch, Haemaccel® and dextran as a possible way for preventing the severe form of OHSS.

OBJECTIVES

To review the effectiveness and safety of administration of intravenous fluids such as albumin, hydroxyethyl starch, Haemaccel® and dextran in the prevention of severe ovarian hyperstimulation syndrome (OHSS) in IVF or ICSI treatment cycles.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Specialised Register of controlled trials, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, to third quarter 2010), MEDLINE (1950 to November 2010), EMBASE (1980 to November 2010) and The National Research Register (to November 2010). The citation lists of relevant publications, review articles, abstracts of scientific meetings and included studies were also searched. The authors were contacted to provide or clarify data that were unclear from the trial reports.

SELECTION CRITERIA

Randomised controlled trials (RCTs) which compared the effects of intravenous fluids with placebo or no treatment for the prevention of severe OHSS in high risk women undergoing IVF or ICSI treatment cycles.

DATA COLLECTION AND ANALYSIS

Two review authors independently scanned the abstracts, identified relevant papers, assessed inclusion of trials and trial quality and extracted relevant data. Validity was assessed in terms of method of randomisation, allocation concealment and outcomes. Where possible, data were pooled for analysis. A separate analysis of studies was performed for human albumin and hydroxyethyl starch versus placebo or no treatment. Other potential intravenous fluids have been identified, such as Haemaccel and dextran, however no randomised controlled studies on their applicability could be found.

MAIN RESULTS

Nine RCTs involving 1660 (human albumin vs placebo) and 487 (HES vs placebo) randomised women, have been included in this review. There was a borderline statistically significant decrease in the incidence of severe OHSS with administration of human albumin (8 RCTs, OR 0.67, 95% CI 0.45 to 0.99).There was a statistically significant decrease in severe OHSS incidence with administration of hydroxyethyl starch (3 RCTs, OR 0.12, 95% CI 0.04 to 0.40). There was no evidence of statistical difference in the pregnancy rate between both groups of treatment.

AUTHORS' CONCLUSIONS

There is limited evidence of benefit from intra-venous albumin administration at the time of oocyte retrieval in the prevention or reduction of the incidence of severe OHSS in high risk women undergoing IVF or ICSI treatment cycles. Hydroxyethyl starch markedly decreases the incidence of severe OHSS.

Coasting (withholding gonadotrophins) for preventing ovarian hyperstimulation syndrome

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic and potentially life threatening condition resulting from excessive ovarian stimulation. Reported incidence varies from 1% to 10% of in vitro fertilization (IVF) cycles. The factors contributing to OHSS have not been completely explained. The release of vasoactive substances secreted by the ovaries under human chorionic gonadotrophin (hCG) stimulation may play a key role in triggering this syndrome. This condition is characterised by a massive shift of fluid from the intra-vascular compartment to the third space resulting in profound intra-vascular depletion and haemoconcentration.

OBJECTIVES

To assess the effect of withholding gonadotrophins (coasting) on the prevention of ovarian hyperstimulation syndrome in assisted reproduction cycles.

SEARCH STRATEGY

For the update of this review we searched the Cochrane Menstrual Disorders and Subfertility Review Group Trials Register (July 2010), CENTRAL (inception to July 2010), MEDLINE (PubMed) (inception to July 2010), and EMBASE (inception to July 2010) for randomised controlled trials (RCTs) in which coasting was used to prevent OHSS.

SELECTION CRITERIA

Only randomised controlled trials (RCTs) in which coasting was used to prevent OHSS were included.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials and extracted data. Disagreements were resolved by discussion. Study authors were contacted to request additional information or missing data. The intervention comparisons were coasting versus early unilateral follicular aspiration (EUFA), no coasting or other interventions. Statistical analysis was performed in accordance with the Cochrane Menstrual Disorders and Subfertility Group guidelines.

MAIN RESULTS

This updated review identified 16 studies of which four met the inclusion criteria. There was no evidence of a difference in the incidence of moderate and severe OHSS (odds ratio (OR) 0.53, 95% CI 0.23 to 1.23), live birth (OR 0.48, 95% CI 0.14 to 1.62; P = 0.24) or in the clinical pregnancy rate (OR 0.69, 95% CI 0.44 to 1.08) between the groups. Significantly fewer oocytes were retrieved in coasting groups compared with GnRHa (OR -2.44, 95% CI -4.30 to -0.58; P = 0.01) or no coasting (OR -3.92, 95% CI -4.47 to -3.37; P < 0.0001). Data for coasting versus EUFA were not pooled for number of oocytes retrieved due to heterogeneity (I(2) = 87%).

AUTHORS' CONCLUSIONS

There was no evidence to suggest a benefit of using coasting to prevent OHSS compared with no coasting or other interventions.