Calcium infusion for the prevention of ovarian hyperstimulation syndrome: a double-blind randomized controlled trial

Calcium versus cabergoline for prevention of ovarian hyperstimulation syndrome: A systematic review and meta-analysis

AIM

To conduct the first-ever systematic review and meta-analysis evaluating calcium infusion versus cabergoline in preventing ovarian hyperstimulation syndrome (OHSS) among high-risk women undergoing assisted reproductive technology.

METHODS

Six databases were screened from inception until April 1, 2024. The included randomized and non-randomized controlled studies were assessed for quality. The endpoints included the severity of OHSS and selected pregnancy-related outcomes. Endpoints were summarized as risk ratios (RRs) and 95% confidence intervals (CIs) in a random-effects model.

RESULTS

Six studies were analyzed, including 1687 patients (828 in the calcium group and 859 in the cabergoline group). The quality of the studies varied and reflected low risk and high risk of bias in two and four studies, respectively, according to the revised Cochrane risk of bias tool. No significant differences were noted between both groups regarding the rates of overall (n = 5, RR = 0.65, 95 % CI [0.39, 1.07], p = 0.09), mild (n = 4, RR = 1.05, 95 % CI [0.59, 1.89], p = 0.86), moderate (n = 5, RR = 0.41, 95 % CI [0.15, 1.08], p = 0.07), and severe (n = 6, RR = 0.36, 95 % CI [0.11, 1.22], p = 0.1) cases of OHSS. Leave-one-out sensitivity analysis of an outlier study revealed that calcium significantly reduced the occurrence of severe OHSS compared with cabergoline (n = 5, RR = 0.16, 95 % CI [0.09, 0.43], p < 0.001, Higgins I2 = 0 %). No significant differences were observed between both groups regarding the rates of clinical pregnancy (n = 4, RR = 0.97, 95 % CI [0.88, 1.07], p = 0.57), ongoing pregnancy, live birth, and spontaneous abortion (Higgins I2 < 50 % for all).

CONCLUSION

Both agents yielded similar pregnancy-related outcomes. However, calcium infusion could potentially be more effective than cabergoline in reducing the rate of severe OHSS. Additional high-quality and well-controlled trials are essential to draw firm conclusions.

Alkali and alkaline earth elements in follicular fluid and the likelihood of diminished ovarian reserve in reproductive-aged women: a case‒control study

BACKGROUND

Imbalances in alkali elements (AEs) and alkaline earth elements (AEEs) cause reproductive disorders. However, it remains unclear whether AEs/AEEs in follicular fluid have a relationship with the serious reproductive disorder known as diminished ovarian reserve (DOR).

METHODS

A nested case‒control study was carried out in China. Follicular fluid samples from 154 DOR patients and 154 controls were collected and assessed for nine AEs/AEE levels. Both the mixed and single effects of the elements on DOR were estimated with a Bayesian kernel machine (BKMR) and logistic regressions.

RESULTS

The DOR group had higher median concentrations of Li, Na, and K in follicular fluid (all P values < 0.05). The logistic regression showed that compared with their lowest tertile, the high tertiles of K [OR:2.45 (1.67-4.43)], Li [OR: 1.89 (1.06-3.42)], and Cs [OR: 1.97 (1.10-3.54)] were significantly associated with the odds of DOR. The BKMR model reported that the DOR likelihood increased linearly across the 25th through 75th percentiles of the nine-AE/AEE mixture, while the AE group contributed more to the overall effect.

CONCLUSION

This study revealed an association in which the likelihood of DOR increased with higher overall concentrations of AE/AEEs in follicular fluid. Among the nine detected elements, K, Li, and Cs exhibited significant individual associations with DOR. We provide new clues for the environmental factors on female fertility decline.

TRIAL REGISTRATION

Retrospectively registered.

Comparison of bromocriptine and hydroxyethyl starch in the prevention of ovarian hyperstimulation syndrome

OBJECTIVE

To evaluate the effectiveness of bromocriptine for prevention of ovarian hyperstimulation syndrome (OHSS).

METHODS

The retrospective study included women at risk of OHSS who were receiving gonadotropin-releasing hormone antagonist protocols, including 52 women given 2.5 mg bromocriptine by rectal insertion, 52 women given 500 ml intravenous hydroxyethyl starch (HES), and 40 women who received no intervention. Treatments were administered daily for 5 days beginning on the day of oocyte retrieval. Baseline information and data related to OHSS were compared.

RESULTS

No significant differences were found among groups in estradiol concentration on the day of trigger or in number of retrieved oocytes. Incidence of mild OHSS was not significantly different among groups, respectively 13.5%, 15.4%, and 17.5% (P > 0.05). The incidence of moderate to severe OHSS was significantly lower in the bromocriptine and HES groups compared with the control group, respectively 7.7%, 5.8%, and 22.5% (P < 0.05). D-dimer levels were significantly lower in the bromocriptine and HES groups compared with the control group on Day 5 after oocyte retrieval (P < 0.05). No differences in liver or renal function were found in the three groups.

CONCLUSION

Bromocriptine was apparently as effective as intravenous HES in patients with high risk of OHSS.

Comparison of the Effectiveness of Various Medicines in the Prevention of Ovarian Hyperstimulation Syndrome: A Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Previous studies have described the effects of different drugs in preventing ovarian hyperstimulation syndrome (OHSS). However, the efficacies of those drugs in preventing OHSS remain inconclusive.

METHODS

We searched the PubMed, Web of Science, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) databases. A network meta-analysis of randomized controlled trials (RCTs) was performed up to August 2021. We investigated the following drugs in our study: aspirin, albumin, metformin, calcium, cabergoline, quinagolide, letrozole, hydroxyethyl starch (HES), and glucocorticoids. The primary outcome was the incidence rate of moderate-to-severe OHSS, with the results presented as risk ratios (RRs) with 95% confidence intervals (CIs).

RESULTS

The incidence of moderate-to-severe OHSS was significantly reduced by calcium administration (risk ratios [RR] 0.14, 95% confidence interval [CI]: 0.04, 0.46) (grade: high), HES (RR 0.25, 95% CI 0.07, 0.73) (grade: high), and cabergoline (RR 0.43, 95% CI 0.24, 0.71) (grade: moderate). The surface under the cumulative ranking curve (SUCRA) indicated that calcium (SUCRA, 92.4%) was the most effective intervention for preventing moderate-to-severe OHSS. These drugs were safe and did not affect clinical pregnancy, miscarriage, or live birth rates.

CONCLUSION

Calcium, HES, and cabergoline could effectively and safely prevent moderate-to-severe OHSS, with calcium as the most effective intervention.

Lipid Analysis of Follicular Fluids by UHPLC-ESI-HRMS Discovers Potential Biomarkers for Ovarian Hyperstimulation Syndrome

Ovarian hyperstimulation syndrome (OHSS) is a serious iatrogenic complication during ovarian stimulation. Even though the incidence of OHSS was relatively low in clinical practice, the consequence can be potentially devastating and life-threatening. Abnormal lipid metabolism may relate to the pathological development of OHSS, but there is still a research gap in the lipidomic research. So here in our study, an ultra-high-performance liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (UHPLC-ESI-HRMS) based lipidomic analysis was performed using follicular fluid samples obtained from 17 patients undergoing OHSS. The lipid profiles of OHSS patients were characterized by increased cholesterol ester (ChE) and decreased lysophosphatidylcholine (LPC), phosphatidylinositol (PI), sphingomyelin (SM), dimethylphosphatidylethanolamine (dMePE) and lysodimethylphosphatidylethanolamine (LdMePE). Totally 10 lipids including LPC(18:0), SM(d18:1/16:0), PC(18:0/18:1), PC(20:2/20:5), PC(16:0/18:1), TG(16:0/18:1/18:1), TG(16:0/18:2/18:2), TG(16:0/16:1/18:1), ChE(20:4) and TG(8:0/8:0/10:0) were selected as differential lipids. In conclusion, this study demonstrated the alteration of various lipids in OHSS patients, which suggested the key role of lipids during the development of OHSS and shed light on the further pathophysiological research of OHSS.

Cabergoline versus calcium infusion in the prevention of ovarian hyperstimulation syndrome: a randomised controlled study

The aim of this study was to compare the efficacy of calcium infusion versus cabergoline in the prevention of ovarian hyperstimulation syndrome (OHSS) in IVF patients at high risk for OHSS. One hundred and seventy patients who were stimulated using the long luteal GnRH agonist protocol and at high risk for developing OHSS were randomised in a 1:1 ratio to cabergoline group and calcium gluconate group. In cabergoline group, 0.5 mg of cabergoline was administered once daily p.o. for eight days starting on the day of HCG administration. In calcium gluconate group, intravenous calcium gluconate (10%, 10 ml in 200 ml of physiologic saline) was administered daily for four days starting on the day of ovum pickup. Six patients in cabergoline group and eight patients in calcium gluconate group developed moderate OHSS. One patient in each group developed severe OHSS. The incidence of moderate/severe OHSS was comparable between both groups (8.24% vs. 10.59%, p value  =  .599, OR = 0.76, 95% CI [0.269-2.138]). The implantation, clinical and ongoing pregnancy rates were similar in the two groups (16.91% vs. 15.84%, p = .771, 35.29% vs. 32.94%, p = .746, and 30.59% vs. 28.24%, p = .736, respectively). In conclusion, calcium infusion and cabergoline have comparable effectiveness in the prevention of OHSS. Both drugs are well tolerated, cheap and have no adverse effects on the reproductive outcomes of IVF cycle.Clinical trial registration: The trial was registered on clinical trials.gov database [NCT02875587].Impact StatementWhat is already known on this subject? The effectiveness of cabergoline in the prevention of OHSS in IVF patients at high risk for OHSS is confirmed by overwhelming scientific evidence. Calcium infusion is a novel strategy for prevention of OHSS. Few studies reported the use of calcium infusion in the prevention of OHSS. A retrospective study and a randomised controlled study revealed that calcium infusion reduces the incidence of OHSS. Moreover, a quasi-randomised study revealed that calcium infusion is as effective as cabergoline in the prevention of OHSS.What the results of this study add? Calcium infusion and cabergoline have comparable effectiveness in the prevention of OHSS. Both drugs are well tolerated, cheap and have no adverse effects on the reproductive outcomes of IVF cycle.What the implications are of these findings for clinical practice and/or further research? Calcium infusion should be used to minimise the incidence of OHSS in IVF patients at high risk for OHSS.

Combined modalities for the prevention of ovarian hyperstimulation syndrome following an excessive response to stimulation

Although the classification and management of ovarian hyperstimulation syndrome (OHSS) are well described in the literature, little attention has been given to modalities that aim to prevent its occurrence. In this retrospective study, we sought to investigate whether a combination of modalities in addition to GnRH agonist triggering in GnRH antagonist cycles could result in better prevention of OHSS. The study included 170 hyperresponder patients who were stimulated with GnRH antagonist protocol and were triggered with GnRH agonist for final oocyte maturation. Freeze all embryos was performed in all patients. The intervention group included treatment with dopamine agonist and restarting the GnRH antagonist. Of the 170 patients included, 63 were included in the intervention group. Compared to no intervention, women in the intervention group were more likely to have: menses within 7 days of the oocyte retrieval, smaller ovarian diameter, the absence of free pelvic fluid, less hemoconcentration and higher serum sodium levels. It can be concluded that combining other modalities in addition to triggering with GnRH agonist in GnRH antagonist cycles, results in targeting several pathways that lead to OHSS and result in rapid resolution of signs of ovarian hyperstimulation.

Pathophysiology, treatment and prevention of ovarian hyperstimulation syndrome

PURPOSE OF REVIEW

Severe ovarian hyperstimulation syndrome (OHSS) is an iatrogenic condition that affects 1% of women that undergo treatment with assisted reproductive technology. The review aims to summarize recent evidence on pathophysiology, treatment, and prevention of OHSS.

RECENT FINDINGS

The pathophysiology is still not completely understood; however, vascular endothelial growth factor is likely to be an important mediator. Human chorionic gonadotropin was previously thought to be necessary for OHSS to occur; however, recent case reports have proven otherwise. The contribution of an attenuated anti-Mullerian hormone signalling pathway and CD11c + HLA-DR + dendritic cells and associated interleukins has been explored recently as contributors to pathogenesis.Treatment is largely supportive and is based mainly on consensus statements rather than evidence. Therefore, it is important to prevent this condition by identifying women at risk, allowing the clinician to implement preventive strategies, including the use of GnRH antagonist cycles with agonist triggers.

SUMMARY

More research is required to elucidate the pathophysiology behind the condition. Clinicians should employ strategies to prevent OHSS.

Prevention and treatment of moderate and severe ovarian hyperstimulation syndrome: a guideline

Ovarian hyperstimulation syndrome (OHSS) is an uncommon but serious complication associated with assisted reproductive technology (ART). This systematic review aims to identify who is at high risk, how to prevent OHSS, and the treatment for existing OHSS.

Volume expanders for the prevention of 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 plasma expanders such as albumin, hydroxyethyl starch (HES), mannitol, polygeline and dextran as a possible intervention for the prevention of OHSS. Women with very high estradiol levels, high numbers of follicles or oocytes retrieved, and women with polycystic ovary syndrome (PCOS), are at particularly high risk of developing OHSS. Plasma expanders are not commonly used nowadays in ovarian hyperstimulation. This is mainly because clinical evidence on their effectiveness remains sparse, because of the low incidence of moderate and severe ovarian hyperstimulation syndrome (OHSS) and the simultaneous introduction of mild stimulation approaches, gonadotropin-releasing hormone (GnRH) antagonist protocols and the freeze-all strategy for the prevention of OHSS.

OBJECTIVES

To review the effectiveness and safety of administration of volume expanders for the prevention of moderate and severe ovarian hyperstimulation syndrome (OHSS) in high-risk women undergoing IVF or ICSI treatment cycles.

SEARCH METHODS

We searched databases including the Cochrane Gynaecology and Fertility Group Specialised Register of controlled trials, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and trial registers to September 2015; no date restrictions were used as new comparators were included in this search. The references of relevant publications were also searched. We attempted to contact authors to provide or clarify data that were unclear from trial or abstract reports.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing volume expanders versus placebo or no treatment for the prevention of OHSS in high-risk women undergoing ovarian hyperstimulation as part of any assisted reproductive technique.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected the studies, assessed risk of bias and extracted relevant data. The primary review outcome was moderate or severe OHSS. Other outcomes were live birth, pregnancy and adverse events. We combined data to calculate pooled Peto odds ratios (ORs) and 95% confidence intervals (CIs) for each intervention. Statistical heterogeneity was assessed using the I(2) statistic. We assessed the overall quality of the evidence for each comparison, using GRADE methods.

MAIN RESULTS

We included nine RCTs (1867 women) comparing human albumin (seven RCTs) or HES (two RCTs) or mannitol (one RCT) versus placebo or no treatment for prevention of OHSS. The evidence was very low to moderate quality for all comparisons. The main limitations were imprecision, poor reporting of study methods, and failure to blind outcome assessment.There was evidence of a beneficial effect of intravenous albumin on OHSS, though heterogeneity was substantial (Peto OR 0.67 95% CI 0.47 to 0.95, seven studies, 1452 high risk women; I² = 69%, very low quality evidence) . This suggests that if the rate of moderate or severe OHSS with no treatment is 12%, it will be about 9% (6% to12%) with the use of intravenous albumin. However, there was evidence of a detrimental effect on pregnancy rates (Peto OR 0.72 95% CI 0.55 to 0.94, I² = 42%, seven studies 1069 high risk women, moderate quality evidence). This suggests that if the chance of pregnancy is 40% without treatment, it will be about 32% (27% to 38%) with the use of albumin.There was evidence of a beneficial effect of HES on OHSS (Peto OR 0.27 95% CI 0.12 to 0.59, I² = 0%, two studies, 272 women, very low quality evidence). This suggests that if the rate of moderate or severe OHSS with no treatment is 16%, it will be about 5% (2% to 10%) with the use of HES. There was no evidence of an effect on pregnancy rates (Peto OR 1.20 95% CI 0.49 to 2.93, one study, 168 women, very low quality evidence).There was evidence of a beneficial effect of mannitol on OHSS (Peto OR 0.38, 95% CI 0.22 to 0.64, one study, 226 women with PCOS, low quality evidence). This means that if the risk of moderate or severe OHSS with no treatment is 52%, it will be about 29% (19% to 41%) with mannitol. There was no evidence of an effect on pregnancy rates (Peto OR 0.85 95% CI 0.47 to 1.55; one study, 226 women, low quality evidence).Live birth rates were not reported in any of the studies. Adverse events appeared to be uncommon, but were too poorly reported to reach any firm conclusions.

AUTHORS' CONCLUSIONS

Evidence suggests that the plasma expanders assessed in this review (human albumin, HES and mannitol) reduce rates of moderate and severe OHSS in women at high risk. Adverse events appear to be uncommon, but were too poorly reported to reach any firm conclusions, and there were no data on live birth. However, there was evidence that human albumin reduces pregnancy rates. While there was no evidence that HES, or mannitol had any influence on pregnancy rates, the evidence of effectiveness was based on very few trials which need to be confirmed in additional, larger randomised controlled trials (RCTs) before they should be considered for routine use in clinical practice.

Pharmacologic Interventions in Preventing Ovarian Hyperstimulation Syndrome: A Systematic Review and Network Meta-Analysis

Ovarian hyperstimulation syndrome (OHSS) is a severe iatrogenic complication of controlled ovarian stimulation. Randomised controlled trials (RCTs) have proven several pharmacologic interventions to be effective in OHSS prevention, but these trials have seldom compared multiple drugs. We identified randomised controlled trials (RCTs) through June 2015 by searching databases and compared 11 intervention strategies in preventing OHSS (primary outcome) and their influence on pregnancy rate (secondary outcome). A network meta-analysis was used to evaluate the relative effectiveness among treatments and to create a rank probability table. Thirty-one RCTs were identified, including 7181 participants. Five pharmacologic interventions were superior to placebo in decreasing OHSS incidence: aspirin [relative risk (RR) 0.07, 95% credible interval (CrI) 0.01-0.30, p < 0.05], intravenous (IV) calcium [RR 0.11, 95% CrI 0.02-0.54, p < 0.05], cabergoline [RR 0.17, 95% CrI 0.06-0.43, p < 0.05], metformin [RR 0.20, 95% CrI 0.07-0.59, p < 0.05] and IV hydroxyethyl starch (HES) [RR 0.26, 95% CrI 0.05-0.99, p < 0.05]. The rank probability demonstrated aspirin (Rank 1: 36%) and IV calcium (Rank 1: 35%) to be the most efficacious. Additionally, albumin might decrease the pregnancy rate when compared with placebo [RR 0.85, 95% CI 0.74-0.97, p < 0.05]. This conclusion provides a relative standard and objective reference for choosing an OHSS prophylactic agent.