Hemodynamic changes induced by urinary human chorionic gonadotropin and recombinant luteinizing hormone used for inducing final follicular maturation and luteinization

Acute cardiovascular changes in women undergoing in vitro fertilisation (IVF), a systematic review and meta-analysis

OBJECTIVES

Ovarian stimulation during fertility treatment leads to profound maternal physiological changes. Women undergoing in vitro fertilisation (IVF) may be at an increased risk of future cardiovascular morbidity, though little is known about the effects on maternal cardiovascular function. We aim to systematically review whether IVF treatment is associated with changes in maternal haemodynamic parameters, and the effects of different protocols.

STUDY DESIGN

A systematic review and meta-analysis of English language studies identified on Medline and EMBASE database, between 1978, to 2019. Search terms: IVF, maternal haemodynamics, and cardiovascular. Studies reporting on ovulation induction, intrauterine insemination, and oocyte donation were excluded. Methodological quality was assessed by using the adapted Critical Appraisal Skills Programme (CASP) checklist. A meta-analysis was conducted for blood pressure and heart rate on patients undergoing the long GnRH agonist protocol according to Cochrane guidelines. We considered four time points in the IVF cycle, in chronological order: pre-treatment, pituitary down regulation, peak oestradiol and the luteal phase.

RESULTS

Nine suitable studies were identified; four fulfilled the criteria for meta-analysis. Two studies measuring heart rate found a significant increase in heart rate from pituitary down-regulation to peak estradiol levels, which was supported by the meta-analysis (3.78 ± 2.18 (p= < 0.0001)). Three studies reported a significant decrease in blood pressure from baseline, with those suitable for meta-analysis showing a significant decrease in mean arterial pressure (-2.08 ± 1.79 (p= < 0.0001)). Cardiac functional changes were reported for all studies and the changes depended on the type of protocol used.

CONCLUSIONS

In Vitro Fertilisation leads to acute changes in maternal haemodynamics at different time points of the stimulation protocol. We found an increase in heart rate from pituitary down-regulation to peak estradiol levels and a significant decrease in blood pressure from baseline or pituitary down-regulation to the luteal phase. Cardiac functional changes were reported for all studies on the agonist protocol, but no significant changes were found using the antagonist protocol. It remains unclear as to whether these acute changes were associated with pregnancy complications or chronic cardiovascular sequelae.

Effect of supraphysiological estrogen levels on arterial stiffness and hemodynamic parameters

OBJECTIVE

The present study evaluates the arterial stiffness and hemodynamic parameters in patients with a supraphysiological estrogen level due to in vitro fertilization (IVF) with controlled ovarian hyperstimulation (COH).

METHODS

A total of 82 female patients aged 24-45 years were included. Their arterial stiffness parameters were analyzed before and after the appropriate COH protocol involving arteriography using Mobil-O-Graph NG (IEM GmbH, Stolberg, Germany) 24-hour ambulatory blood pressure monitor.

RESULTS

Systolic, diastolic, mean, central systolic, and diastolic blood pressures, as well as peripheral vascular resistance, were significantly lower after COH therapy (p=0.001, 0.002, <0.001, <0.001, 0.040, and <0.001, respectively). In contrast, there was no statistically significant difference observed in heart rate, pulse pressure, or cardiac output. The pulse wave velocity measurement was significantly lower after COH than the baseline levels [5.3 m/s (4.5-6.9 m/s) versus 5.4 m/s (4.7-7.3 m/s,); p<0.001], but the augmentation index was not significantly different [28% (4%-41%) versus 29% (5%-43%); p=0.090]. When the patients were grouped according to the occurrence of a pregnancy after IVF therapy, all parameters were not different between the pregnancy (+) and pregnancy (-) patients (p>0.05).

CONCLUSION

Arterial stiffness and hemodynamic parameters significantly decreased in IVF patients who underwent COH therapy. The long-term clinical significance of this short-term effect should be investigated with prospective studies. There was no significant difference in all parameters before and after COH when the pregnancy (+) and pregnancy (-) patients were compared.

Novel Concepts for Inducing Final Oocyte Maturation in In Vitro Fertilization Treatment

Infertility affects one in six of the population and increasingly couples require treatment with assisted reproductive techniques. In vitro fertilization (IVF) treatment is most commonly conducted using exogenous FSH to induce follicular growth and human chorionic gonadotropin (hCG) to induce final oocyte maturation. However, hCG may cause the potentially life-threatening iatrogenic complication "ovarian hyperstimulation syndrome" (OHSS), which can cause considerable morbidity and, rarely, even mortality in otherwise healthy women. The use of GnRH agonists (GnRHas) has been pioneered during the last two decades to provide a safer option to induce final oocyte maturation. More recently, the neuropeptide kisspeptin, a hypothalamic regulator of GnRH release, has been investigated as a novel inductor of oocyte maturation. The hormonal stimulus used to induce oocyte maturation has a major impact on the success (retrieval of oocytes and chance of implantation) and safety (risk of OHSS) of IVF treatment. This review aims to appraise experimental and clinical data of hormonal approaches used to induce final oocyte maturation by hCG, GnRHa, both GnRHa and hCG administered in combination, recombinant LH, or kisspeptin. We also examine evidence for the timing of administration of the inductor of final oocyte maturation in relationship to parameters of follicular growth and the subsequent interval to oocyte retrieval. In summary, we review data on the efficacy and safety of the major hormonal approaches used to induce final oocyte maturation in clinical practice, as well as some novel approaches that may offer fresh alternatives in future.

Arterial stiffness during controlled ovarian hyperstimulation and early pregnancy in women exposed to assisted reproduction

INTRODUCTION

Female sex hormones have vasorelaxing effects in non-pregnant and pregnant women. We aimed to investigate the effect of controlled ovarian hyperstimulation (COH) for in vitro fertilization (IVF), and early pregnancy, on arterial stiffness as assessed by digital pulse wave analysis (DPA), hypothesizing reduced arterial stiffness as an effect of increased estrogen levels.

MATERIAL AND METHODS

A total of 68 women undergoing IVF were examined with DPA before conception and during IVF treatment with COH and embryo transfer (ET), and in gestational week seven in 19 women who became pregnant. Heart rate (HR), mean arterial pressure (MAP) and the DPA variables cardiac ejection elasticity index (EEI), b/a, dicrotic index (DI), d/a and aging index (AI) were measured.

RESULTS

HR was significantly increased at all measuring points (p ≤ 0.003) but MAP only at ET (p 0.007). DPA variables representing large arteries (EEI, b/a) and peripheral arteries (DI, but not d/a), and the global variable AI, indicated increased arterial stiffness at ET compared with baseline (p ≤ 0.035). No DPA variable was significantly changed at pregnancy measurements compared to baseline.

CONCLUSION

During COH for IVF treatment, DPA showed no changes in arterial stiffness during the follicular phase or in early pregnancy, but increased arterial stiffness in central and peripheral arteries in the early luteal phase. The result suggests a hormonal hemodynamic activation counteracting the effects of estrogen.

Assessment of arterial function in pregnancy: recommendations of the International Working Group on Maternal Hemodynamics

There is strong evidence supporting the role of maternal arterial dysfunction in pregnancy-specific disorders such as pre-eclampsia and intrauterine growth restriction. As more work is focused towards this field, it is important that methods and interpretation of arterial function assessment are applied appropriately. Here, we summarize techniques and devices commonly used in maternal health studies, with consideration of their technical application in pregnant cohorts. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Influence of two ovulation-inducing agents on the pituitary response and follicle blood flow in mares

The objective of the current study was to evaluate the effects of deslorelin and hCG, two ovulation-inducing therapies, on LH surge and follicle vascularity in mares. Thirty mares were either treated with 1.5 mg IM of deslorelin, 2,500 IU IV of hCG or 2 mL IM of NaCl 0.9% (GnRH, hCG and Saline groups, respectively). Power-flow Doppler examination and blood collection were performed every hour during the first 12 hours after treatment (H0) and every six hours between hours 12 (H12) and 30 (H30) after treatment. Moreover, endpoints were evaluated every hour through the last six hours before ovulation (OV-6 to OV-1). In GnRH group, plasma LH concentration progressively increased (P < 0.001) during the first 6 hours after treatment and remained high (P > 0.1) until OV-1. A significant increase in LH concentrations was first detected (P < 0.05) at 24 hours after treatment in hCG group, while no changes (P > 0.1) on LH levels were found during H0-H30 and between OV-6 and OV-1 in the Saline group. Independent of the treatment, significant variations on the percentage of the follicle wall with Doppler signals were not observed (P > 0.1) throughout the entire experiment. A weak correlation between the preovulatory follicle vascularity and the plasma LH concentration was found in GnRH, hCG and Saline groups (r = +0.29, +0.29 and -0.23, respectively; P ˂ 0.0001). These results described for the first time the immediate and continuous pituitary response to ovulation-inducing therapy with injectable deslorelin. Moreover, spontaneous and induced ovulations were not preceded by an increased follicle vascularity, which differs from previous reports in large animals.

Recombinant versus urinary human chorionic gonadotrophin for final oocyte maturation triggering in IVF and ICSI cycles

BACKGROUND

For the last few decades urinary human chorionic gonadotrophin (uhCG) has been used to trigger final oocyte maturation in cycles of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). Recombinant technology has allowed the production of two drugs, recombinant human chorionic gonadotrophin (rhCG) and recombinant luteinising hormone (rLH), that can be used for the same purpose, to mimic the endogenous luteinising hormone (LH) surge. This allows commercial manufacturers to adjust production according to market requirements and to remove all urinary contaminants, facilitating the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice, it is necessary to compare the effectiveness of the recombinant drugs to the currently used urinary human chorionic gonadotrophin (uhCG).

OBJECTIVES

To assess the effects of subcutaneous rhCG and high dose rLH versus uhCG for inducing final oocyte maturation in subfertile women undergoing IVF and ICSI cycles.

SEARCH METHODS

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (April 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (2015, Issue 3), MEDLINE (1946 to April 2015), EMBASE (1980 to April 2015) and PsycINFO (1806 to April 2015) as well as trial registers at ClinicalTrials.gov on 13 May 2015 and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) search portal on 14 May 2015.

SELECTION CRITERIA

Two review authors independently scanned titles and abstracts and selected those that appeared relevant for collection of the full paper. We included randomised controlled trials comparing rhCG and rLH with urinary hCG for final oocyte maturation triggering in IVF and ICSI cycles for treatment of infertility in normogonadotropic women.

DATA COLLECTION AND ANALYSIS

Two authors independently performed assessment for inclusion or exclusion, quality assessment and data extraction. We discussed any discrepancies in the presence of a third author to reach a consensus. The primary review outcomes were ongoing pregnancy/live birth and incidence of ovarian hyperstimulation syndrome (OHSS). Clinical pregnancy, miscarriage rate, number of oocytes retrieved and adverse events were secondary outcomes. We combined data to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs) and assessed statistical heterogeneity using the I(2) statistic. We evaluated the overall quality of the evidence for the main comparisons using GRADE methods.

MAIN RESULTS

We included 18 RCTs involving 2952 participants; 15 compared rhCG with uhCG, and 3 compared rhLH with uhCG. The evidence for different comparisons ranged from very low to high quality: limitations were poor reporting of study methods and imprecision. Pharmaceutical companies funded 9 of the 18 studies, and 5 studies did not clearly report funding source. Ongoing pregnancy/live birthThere was no conclusive evidence of a difference between rhCG and uhCG (OR 1.15, 95% CI 0.89 to 1.49; 7 RCTs, N = 1136, I(2) = 0%, moderate quality evidence) or between rhLH and uhCG (OR 0.95, 95% CI 0.51 to 1.78, 2 RCTs, N = 289, I(2) = 0%, very low quality evidence) for ongoing pregnancy/live birth rates. OHSS There was no evidence of a difference between rhCG and uhCG in the incidence of OHSS: moderate to severe OHSS (OR 1.76, 95% CI 0.37 to 8.45; 3 RCTs, N = 417, I(2) = 0%, low quality evidence), moderate OHSS (OR 0.78, 95% CI 0.27 to 2.27; 1 RCT, N = 243, I(2) = 0%, low quality evidence), mild to moderate OHSS (OR 1.00, 95% CI 0.42 to 2.38; 2 RCTs, N = 320, I(2) = 0%, low quality evidence) or undefined OHSS (OR 1.18, 95% CI 0.50 to 2.78; 3 RCTs, N = 495, I(2) = 0%, low quality evidence). Likewise, there was no evidence of a difference between rhLH and uhCG in OHSS rates for moderate OHSS (OR 0.82, 95% CI 0.39 to 1.69, 2 RCTs, N = 280, I(2) = 5%, very low quality evidence). Other adverse events There was no evidence of a difference in miscarriage rates between rhCG and uhCG (OR 0.72, 95% CI 0.41 to 1.25; 8 RCTs, N = 1196, I(2) = 0%, low quality evidence) or between rhLH and uhCG (OR 0.95, 95% CI 0.38 to 2.40; 2 RCTs, N = 289, I(2) = 0%, very low quality evidence). For other adverse effects (most commonly injection-site reactions) rhCG was associated with a lower number of adverse events than uhCG (OR 0.52, 95% CI 0.35 to 0.76; 5 RCTS, N = 561; I(2) = 67%, moderate quality evidence). However, when we used a random-effects model due to substantial statistical heterogeneity, there was no evidence of a difference between the groups (OR 0.56, 95% CI 0.27 to 1.13). Only one study comparing rLH and uhCG reported other adverse events, and it was impossible to draw conclusions.

AUTHORS' CONCLUSIONS

We conclude that there is no evidence of a difference between rhCG or rhLH and uhCG for live birth or ongoing pregnancy rates or rates of OHSS.

Ovarian hyperstimulation syndrome: pathophysiology, staging, prediction and prevention

OBJECTIVE

To identify, appraise and summarize the current evidence regarding the pathophysiology, staging, prediction and prevention of ovarian hyperstimulation syndrome (OHSS).

METHODS

Two comprehensive systematic reviews were carried out: one examined methods of predicting either high ovarian response or OHSS and the other examined interventions aimed at reducing the occurrence of OHSS. Additionally, we describe the related pathophysiology and staging criteria.

RESULTS

Seven studies examining methods of predicting OHSS and eight more examining methods of predicting high ovarian response to controlled ovarian stimulation were included. Current evidence shows that the best methods of predicting high response are antral follicle count and anti-Müllerian hormone levels, and that a high ovarian response (examined by the number of large follicles, estradiol concentration or the number of retrieved oocytes) is the best method of predicting the occurrence of OHSS. Ninety-seven randomized controlled trials examining the effect of several interventions for reducing the occurrence of OHSS were included. There was high-quality evidence that replacing human chorionic gonadotropin by gonadotropin-releasing hormone agonists or recombinant luteinizing hormone, and moderate-quality evidence that antagonist protocols, dopamine agonists and mild stimulation, reduce the occurrence of OHSS. The evidence for the effect of the other interventions was of low/very low quality. Additionally, we identified and described 12 different staging criteria.

CONCLUSIONS

There are useful predictive tools and several preventive interventions aimed at reducing the occurrence of OHSS. Acknowledging and understanding them are of crucial importance for planning the treatment of, and, ultimately, eliminating, OHSS while maintaining high pregnancy rates.

In anesthetized pigs human chorionic gonadotropin increases myocardial perfusion and function through a β-adrenergic-related pathway and nitric oxide

Human chorionic gonadotropin (hCG) is not only responsible for numerous pregnancy-related processes, but can affect the cardiovascular system as well. So far, however, information about any direct effect elicited by hCG on cardiac function, perfusion, and the mechanisms involved has remained scarce. Therefore, the present study aimed to determine the primary in vivo effect of hCG on cardiac contractility and coronary blood flow and the involvement of autonomic nervous system and nitric oxide (NO). Moreover, in coronary endothelial cells (CEC), the intracellular pathways involved in the effects of hCG on NO release were also examined. In 25 anesthetized pigs, intracoronary 500 mU/ml hCG infusion at constant heart rate and aortic blood pressure increased coronary blood flow, maximum rate of change of left ventricular systolic pressure, segmental shortening, cardiac output, and coronary NO release (P < 0.0001). These hemodynamic responses were graded in a further five pigs. Moreover, while blockade of muscarinic cholinoceptors (n = 5) and of α-adrenoceptors (n = 5) did not abolish the observed responses, β1-adrenoceptors blocker (n = 5) prevented the effects of hCG on cardiac function. In addition, β2-adrenoceptors (n = 5) and NO synthase inhibition (n = 5) abolished the coronary response and the effect of hCG on NO release. In CEC, hCG induced the phosphorylation of endothelial NO synthase through cAMP/PKA signaling and ERK1/2, Akt, p38 MAPK involvement, which were activated as downstream effectors of β2-adrenoceptor stimulation. In conclusion, in anesthetized pigs, hCG primarily increased cardiac function and perfusion through the involvement of β-adrenoceptors and NO release. Moreover, cAMP/PKA-dependent kinases phosphorylation was found to play a role in eliciting the observed NO production in CEC.

Recombinant versus urinary human chorionic gonadotrophin for final oocyte maturation triggering in IVF and ICSI cycles

BACKGROUND

For the last few decades urinary human chorionic gonadotrophin (hCG) has been used to induce final oocyte maturation triggering in in vitro fertilization (IVF) and intra-cytoplasmic sperm injection (ICSI) cycles. Recombinant technology has allowed the production of two drugs that can be used for the same purpose, to mimic the endogenous luteinizing hormone (LH) surge. This allows commercial production to be adjusted according to market requirements; the removal of all urinary contaminants; and the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice the effectiveness of the recombinant drugs should be known compared to the currently used urinary human chorionic gonadotrophin (uhCG).

OBJECTIVES

To assess the efficacy and safety of subcutaneous recombinant hCG (rhCG) and high dose recombinant LH (rLH) compared with intramuscular uhCG for inducing final oocyte maturation triggering in IVF and ICSI cycles.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group Trials Register (January 2010), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010), MEDLINE (1966 to January 2010) and EMBASE (1980 to January 2010).

SELECTION CRITERIA

Two review authors independently scanned titles and abstracts and selected those that appeared relevant for collection of the full paper. Only truly randomised controlled trials comparing rhCG and rLH with urinary hCG for final oocyte maturation triggering in IVF and ICSI cycles for treatment of infertility in normo-gonadotropic women were included.

DATA COLLECTION AND ANALYSIS

Assessment for inclusion or exclusion, quality assessment and data extraction were performed independently by two authors. Discrepancies were discussed in the presence of a third author and consensus reached. Quality assessment included method of randomisation, allocation concealment, blinding of participants and assessors, reporting of a power calculation and intention-to-treat analysis.

MAIN RESULTS

Fourteen RCTs (n = 2306) were identified; 11 compared rhCG with uhCG and three compared rhLH with uhCG. There was no evidence of a statistically significant difference between rhCG and uhCG regarding the ongoing pregnancy or live birth rate (6 RCTs: OR 1.04, 95% CI 0.79 to 1.37; P = 0.83, I(2) = 0%). There was no significant difference in the incidence of ovarian hyperstimulation syndrome (OHSS) between rhCG and uhCG (3 RCTs: OR 1.5, 95% CI 0.37 to 4.1; P = 0.37, I(2) = 0%). There was no evidence of statistically significant difference between rhLH and uhCG regarding the ongoing pregnancy or live birth rate (OR 0.94, 95% CI 0.50 to 1.76) and incidence of OHSS (OR 0.82, 95% CI 0.39 to 1.69). These results leave open the possibility of strong differences in favour of either treatment for both ongoing pregnancy and OHSS.

AUTHORS' CONCLUSIONS

We conclude that there is no evidence of difference between rhCG or rhLH and uhCG in achieving final follicular maturation in IVF, with equivalent pregnancy rates and OHSS incidence. According to these findings uHCG is still the best choice for final oocyte maturation triggering in IVF and ICSI treatment cycles.

Ovarian luteinizing hormone priming preceding follicle-stimulating hormone stimulation: clinical and endocrine effects in women with long-term hypogonadotropic hypogonadism

CONTEXT

Patients with hypogonadotropic hypogonadism (HH), who may be totally LH deficient, remain the primary clinical model for investigating the physiology of gonadotropin actions on ovarian steroidogenesis and follicular development.

OBJECTIVES

Our objective was to investigate the effects of LH pretreatment on subsequent ovarian stimulation with FSH in longstanding HH women.

DESIGN AND SETTING

A prospective, self-controlled study was conducted at a university tertiary-care center.

PATIENTS AND INTERVENTIONS

Eight HH women (six idiopathic, two surgical) underwent ovarian stimulation with recombinant human (rh)FSH preceded or not by rhLH administration in two separate cycles. In one additional patient with idiopathic HH, pretreatment was conducted with recombinant human chorionic gonadotropin (rhCG) instead of rhLH.

MAIN OUTCOME MEASURES

Follicular development and serum hormone concentrations throughout LH-FSH and FSH treatment cycles were assessed.

RESULTS

Pretreatment with rhLH significantly decreased the mean threshold (daily effective) FSH dose and tended to lower the total amount of FSH required to induce follicular maturation in association with appropriate serum estradiol levels and endometrial thickness. Unexpectedly, in HH women retaining functional pituitary tissue, pretreatment with rhLH evoked a consistent elevation of serum LH levels during FSH administration, an effect that was also induced, even at higher magnitude, by pretreatment with rhCG.

CONCLUSIONS

In addition to changes in FSH requirements for follicular maturation, pretreatment with rhLH/rhCG evoked unambiguous elevations in serum levels of endogenous LH during FSH treatment in HH patients with preserved pituitary function. This is suggestive of a novel regulatory loop of LH secretion involving gonadotropin-stimulated ovarian factors whose nature and physiological relevance are yet to be disclosed, ovarian-derived kisspeptins being appealing candidates.

Maternal cardiac output between 11 and 13 weeks of gestation in the prediction of preeclampsia and small for gestational age

OBJECTIVE

To investigate maternal cardiac output in the first trimester as a predictor of preeclampsia and delivery of small for gestational age (SGA) infants.

METHODS

In women attending for routine care between 11(+0) and 13(+6) weeks of gestation, we recorded maternal variables and measured cardiac output by echocardiography. We compared cardiac output in those that developed preeclampsia (n=83), pregnancy-induced hypertension (PIH) (n=87), or SGA (n=532) with those unaffected by preeclampsia, PIH, or SGA (n=3,591). Regression analysis was used to first determine which of the factors among the maternal variables were significant predictors of cardiac output in the unaffected group and, secondly, to predict each complication by a combination of maternal variables and cardiac output.

RESULTS

In the unaffected group, cardiac output increased with gestation and maternal weight and decreased with maternal age. Cardiac output was higher in parous women, in cigarette smokers, in those taking antihypertensive or beta-mimetic medications, and in those conceiving after in vitro fertilization, and lower in women of Afro-Caribbean origin. Compared with the unaffected group, cardiac output was significantly higher in the preeclampsia and PIH groups and lower in the SGA group. In screening by cardiac output and maternal variables, for a 10% false-positive rate, the detection rates were 43.4% for all preeclampsia, 52% for preeclampsia without SGA, 23.3% for PIH, and 23.9% for SGA.

CONCLUSION

In pregnancies complicated by preeclampsia, PIH, and SGA, alterations in maternal cardiac output predate the clinical onset of the disorders by several months. Maternal cardiac output in the first trimester is increased in women who develop preeclampsia and decreased in women who deliver SGA infants.

LEVEL OF EVIDENCE

II.

Evidence of improving quality of reporting of randomized controlled trials in subfertility

BACKGROUND

The quality of randomized controlled trials (RCTs) in subfertility and their suitability for inclusion in meta-analyses have been assessed in the past and found to be insufficient. Our aim was to assess whether this quality has improved over time, particularly since the publication of the Consolidated Standards of Reporting Trials (CONSORT) statement, and to assess what proportion of trials could be included in the meta-analyses of pregnancy outcomes such as those included in Cochrane Reviews.

METHODS

A selection of subfertility trials published in 1990, 1996 and 2002 was collected from the Cochrane Menstrual Disorder and Subfertility Group (MDSG) database. Only trials published in English as full journal articles, claiming to be randomized and reporting on pregnancy outcomes, were included.

RESULTS

One hundred and sixty-four trials met our inclusion criteria. Twenty-four (15%) were found not to be randomized, despite claims, and only 10 trials (6%) provided adequate details on the methods of randomization and allocation concealment. Of these, only three had sufficient details extractable to allow for an intention-to-treat analysis of the outcome 'live birth'.

CONCLUSIONS

Although an improvement in some subfertility-specific issues was observed, the quality of reporting of RCTs still needs to improve to make them suitable for inclusion in meta-analyses such as those in the Cochrane Library.

Recombinant versus urinary human chorionic gonadotrophin for ovulation induction in assisted conception

BACKGROUND

For the last few decades urinary human chorionic gonadotrophin has been used to induce final follicular maturation and for triggering ovulation in assisted conception. Recombinant technology has allowed the production of two drugs that can be used for the same purpose: to mimic the endogenous luteinizing hormone (LH) surge. This would allow commercial production to be adjusted according to market requirements. In addition all urinary contaminants would also be removed. Hence, this would allow the safe subcutaneous administration of a compound with less batch-to-batch variation. However, prior to a change in practice, the effectiveness of the recombinant drugs should be known, compared to the currently used urinary human chorionic gonadotrophins.

OBJECTIVES

To assess the safety and efficacy of subcutaneous rhCG and high dose rLH compared with intramuscular uhCG for inducing final oocyte maturation and triggering ovulation.

SEARCH STRATEGY

We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (27 August 2003), the Cochrane Central Register of Controlled Trials (CENTRAL on The Cochrane Library, issue 4, 2003), MEDLINE (1966 to Feb 2004) and EMBASE (1980 to Feb 2004). Searches were not limited by language. The bibliographies of included, excluded trials and abstracts of major meetings were searched for additional trials. Authors and pharmaceutical companies were contacted for missing and unpublished data.

SELECTION CRITERIA

Two reviewers independently scanned titles and abstracts, and selected those that appeared relevant for collection of the full paper. Only truly randomised controlled trials comparing rhCG or high dose r-LH with urinary hCG for triggering ovulation in assisted conception for treatment of infertility in normogonadotrophic women were included.

DATA COLLECTION AND ANALYSIS

Assessment of inclusion/exclusion, quality assessment and data extraction were performed independently by at least two reviewers. Discrepancies were discussed in the presence of a third reviewer and a consensus reached. Quality assessment included method of randomisation, allocation concealment, blinding of participants and assessors, reporting of a power calculation, intention to treat analysis, and handling of dropouts. Data extraction included characteristics of participants, the intervention and control procedures, and outcomes.

MAIN RESULTS

Seven RCTs were identified, four comparing rhCG and uhCG and three comparing rhLH and uhCG. There was no statistically significant difference between rhCG vs uhCG regarding the ongoing pregnancy/ live birth rate (OR 0.98, 95% CI 0.69 to 1.39), pregnancy rate, miscarriage or incidence of OHSS. There was no statistically significant difference between rhLH vs uhCG regarding the ongoing pregnancy/ live birth rate (OR 0.94, 95% CI 0.50 to 1.76), pregnancy rate, miscarriage or incidence of OHSS. The manufacturer of rhLH has decided not to further develop this product. rhCG was associated with a reduction in the incidence of local site reactions and other minor adverse effects (OR 0.47, 95% CI 0.32 to 0.70).

AUTHORS' CONCLUSIONS

There is no evidence of difference in clinical outcomes between urinary and recombinant gonadotrophins for induction of final follicular maturation. Additional factors should be considered when choosing gonadotrophin type, including safety, cost and drug availability.

The role of luteinizing hormone activity in controlled ovarian stimulation

The role of LH in the natural menstrual cycle is undisputed. The active participation of LH in both steroidogenesis and ovulation is well established, but its potential effect on oocyte maturation in the issue of assisted reproduction protocols remains a topic of debate. Although several studies have added to our understanding of the specific actions of androgens in human follicular development, some discrepancies persist regarding their role in oocyte atresia. Clinical situations, where LH is either decreased or absent (e.g. in women with hypogonadotrophic hypogonadism or LH-receptor gene mutations), provide important data supporting the necessity for a minimal amount of LH to evoke ovulation. Recent use of GnRH antagonists, which results in profound suppression of LH concentration, in combination with the pharmacological production of recombinant gonadotrophins, has attracted the attention of investigators. Identification of sub-fertilized women, in whom LH administration could be beneficial and should be indicated, is arousing ever more interest. Based on the available data in the literature, the aims of this review are to assess the role of both endogenous and exogenous LH activity in stimulated cycles, and to evaluate the effects of recombinant human LH supplementation on the ovarian hormonal milieu and on the main outcomes of controlled stimulated cycles.

Administration of low-dose LH induces ovulation and prevents vascular hyperpermeability and vascular endothelial growth factor expression in superovulated rats

The administration, to rats, of a combination of pregnant mares serum gonadotrophin (PMSG) and human chorionic gonadotrophin (hCG) in high doses induces the ovarian hyperstimulation syndrome (OHSS) which is characterized by increased vascular permeability (VP) and simultaneous overexpression of vascular endothelial growth factor (VEGF) in ovarian cells. hCG has a longer half-life than LH and a greater biological activity, expressed in a higher incidence of complications such as OHSS. Similarly, FSH may also be related to the ovulatory changes within the follicle as there is a simultaneous surge in spontaneous cycles. The aim of this study was to compare the capacity of hCG, FSH and LH to induce ovulation and simultaneously prevent OHSS in the animal model. Immature female rats were treated with 10 IU PMSG for 4 days, and ovulation was triggered with saline, 10 IU hCG, 10 IU FSH, 10 IU LH or 60 IU LH. The number of oocytes ovulated into the tubes, VP and mRNA VEGF expression were evaluated and compared.

All the hormones employed were as effective at triggering ovulation, with similar significant P values when compared with the control for which saline was used. The use of 10 IU LH resulted in significantly lower VP and VEGF expression than that seen in the groups treated with 10 IU hCG, 10 IU FSH or 60 IU LH. In conclusion, FSH and hCG, as well as a sixfold increase in LH, displayed similar biological activities, including increased VP due to excessive VEGF expression. The use of lower doses of LH produced similar rates of ovulation, while preventing the undesired changes in permeability. These experiments should therefore encourage clinicians to determine the optimal dose of LH to be employed in women in order to trigger ovulation and, at the same time, avoid the risk of OHSS.