C.O. Nastri

Ovarian hyperstimulation syndrome: pathophysiology and prevention

PurposeTo review and discuss the pathophysiology and prevention strategies for ovarian hyperstimulation syndrome (OHSS), which is a condition that may occur in up to 20% of the high risk women submitted to assisted reproductive technology cycles.MethodsThe English language literature on these topics were reviewed through PubMed and discussed with emphasis on recent data.ResultsThe role of estradiol, luteinizing hormone, human chorionic gonadotropin (hCG), inflammatory mediators, the renin-angiotensin system and vascular endothelial growth factor is discussed in the pathophysiology of OHSS. In addition we consider the prevention strategies, including coasting, administration of albumin, renin-angiotensin system blockage, dopamine agonist administration, non-steroidal anti-inflammatory administration, GnRH antagonist protocols, reducing hCG dosage, replacement of hCG and in vitro maturation of oocytes (IVM).ConclusionsAmong the many prevention strategies that have been discussed, the current evidence points to the replacement of hCG by GnRH agonists in antagonist cycles and the performance of IVM procedures as the safest approaches.

Assisted hatching of human embryos: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND Assisted hatching (AH) is a manipulation of zona pellucida aiming to facilitate embryo implantation. METHODS Systematic review and meta-analysis of medical literature was used to evaluate the effect of AH on assisted reproduction outcomes: clinical pregnancy, live birth, multiple pregnancy and miscarriage. Additional analysis was performed in these subgroups: (i) fresh embryos transferred to unselected or non-poor prognosis women; (ii) fresh embryos transferred to women with previous repeated failure; (iii) fresh embryos transferred to women of advanced age; (iv) frozen-thawed embryos transferred to unselected or non-poor prognosis women. Analyses were based on risk ratio and 95% confidence intervals (RR, 95% CIs) using Mantel-Haenszel random effects model. RESULTS There were 28 studies (5507 participants) included. AH was related to a trend toward increased clinical pregnancy for all participants (RR = 1.11, 95% CI = 1.00-1.24), with a significant increase in subgroups 2 (RR = 1.73; 95% CI = 1.37-2.17) and 4 (RR = 1.36; 95% CI = 1.08-1.72, P< 0.01), but not for subgroups 1 and 3. For multiple pregnancy, a significant increase was observed for all participants (RR = 1.45; 95% CI = 1.11-1.90) and for subgroups 2 (RR = 2.53; 95% CI = 1.23-5.21) and 4 (RR = 3.40; 95% CI = 1.93-6.01). No significant heterogeneity was observed in subgroup analysis. CONCLUSIONS AH was related to increased clinical pregnancy and multiple pregnancy rates in women with previous repeated failure or frozen-thawed embryos. However, AH is unlikely to increase clinical pregnancy rates when performed in fresh embryos transferred to unselected or non-poor prognosis women or to women of advanced age. Due to the small sample evaluated by the pool of included studies, no proper conclusions could be drawn regarding miscarriage or live birth.

Quantitative three-dimensional power Doppler angiography: a flow-free phantom experiment to evaluate the relationship between color gain, depth and signal artifact

To evaluate the presence of false flow three‐dimensional (3D) power Doppler signals in ‘flow‐free’ models.

Endometrial scratching performed in the non-transfer cycle and outcome of assisted reproduction: a randomized controlled trial

To investigate the effect of endometrial scratching, performed during oral contraceptive pill (OCP) pretreatment, on reproductive outcome and on ultrasound markers of endometrial receptivity, and to assess the pain involved in the procedure, in unselected women undergoing assisted reproductive techniques (ART).

Reliability and validity of tissue volume measurement by three-dimensional ultrasound: an experimental model

To determine the validity and the intra‐ and interobserver reliability of volume measurements of an endometrium‐like model using a three‐dimensional (3D) ultrasound rotational technique.

Impact of endometriosis and its staging on assisted reproduction outcome: systematic review and meta-analysis.

To evaluate whether the presence or severity of endometriosis affects the outcome of assisted reproductive techniques (ART).

Cabergoline for the prevention of ovarian hyperstimulation syndrome: systematic review and meta-analysis of randomized controlled trials

OBJECTIVE To evaluate the efficacy and safety of using cabergoline for reducing the risk of ovarian hyperstimulation syndrome (OHSS). DESIGN Systematic review and meta-analysis of randomized clinical trials (RCTs). PATIENTS Women submitted to controlled ovarian stimulation (COS) for assisted reproduction. INTERVENTIONS Cabergoline. SETTING Fertility centers. MAIN OUTCOME MEASURES Moderate-severe OHSS, live birth, clinical pregnancy, number of retrieved oocytes, miscarriage, congenital abnormalities. Comparisons were performed with the use of risk ratios (RRs) or mean differences (MDs) and their respective 95% confidence intervals (CIs). RESULT(S) Eight RCTs were considered to be eligible; data from seven studies could be extracted and included in the meta-analysis. Cabergoline reduces the risk of moderate-severe OHSS (RR 0.38, 95% CI 0.29-0.51, 7 studies, 858 women) and probably has no clinically relevant negative impact on clinical pregnancy (RR 1.02, 95% CI 0.78-1.34, 4 studies, 561 women) or on the number of retrieved oocytes (MD 1.15, 95% CI -0.76 to 3.07, 5 studies, 628 women). However, our estimates were imprecise for distinguishing between substantial harm, no effect, and substantial benefit considering live birth (RR 1.03, 95% CI 0.71-1.48, 1 study, 200 women), and miscarriage (RR 0.69, 95% CI 0.27 to 1.76, 3 studies, 194 pregnant women). No studies reported congenital abnormalities. CONCLUSION(S) Cabergoline reduces the occurrence of moderate-severe OHSS. Cabergoline is unlikely to have a clinically relevant negative impact on clinical pregnancy or on the number of retrieved oocytes. However, we are still uncertain of its impact on live birth, miscarriage, and congenital abnormalities.

Lower uterine segment thickness measurement in pregnant women with previous Cesarean section: reliability analysis using two- and three-dimensional transabdominal and transvaginal ultrasound

To evaluate the reliability of two‐ and three‐dimensional ultrasonographic measurement of the thickness of the lower uterine segment (LUS) in pregnant women by transvaginal and transabdominal approaches.

Ovarian hyperstimulation syndrome: pathophysiology, staging, prediction and prevention.

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

The "volumetric" pulsatility index as evaluated by spatiotemporal imaging correlation (STIC): a preliminary description of a novel technique, its application to the endometrium and an evaluation of its reproducibility.

We propose new volumetric indices derived from three-dimensional (3-D) power Doppler (PD) using spatiotemporal imaging correlation (STIC) to overcome the influence of machine settings and attenuation. In this study, we describe these indices and evaluate their interobserver reliability: two static-3-D and two STIC PD datasets were acquired from 60 women and two observers (blinded analysis) evaluated vascularization index (VI), the flow index (FI) and the vascularization flow index (VFI) of standardized spherical samples of endometrium. Three new indices were determined based on maximum, minimum and mean values (vPI, vRI(max-min), vS/D(max-min)) and two indices from frames subjectively defined as systole and diastole (vRI(sys-dia), vS/D(sys-dia)). Highest intraclass coefficient correlations (ICCs) were obtained from vPI derived from VI or VFI (0.77-0.76), followed by vRI(max-min) (0.72-0.72) and vS/D(max-min) (0.52-0.49). ICCs from indices based on subjectively systole and diastole or FI were consistently lower (<0.40). We conclude that the subjective choice of systolic and diastolic frames only lacks reliability but indices based on complete evaluation may reliably be used.