Depressive symptoms as assessed herein increased during transition to menopause and decreased in postmenopausal women. Hormone associations provided corroborating evidence that the changing hormonal milieu contributes to dysphoric mood during transition to menopause.
BACKGROUNDSuccessful cryopreservation of oocytes and embryos is essential not only to maximize the safety and efficacy of ovarian stimulation cycles in an IVF treatment, but also to enable fertility preservation. Two cryopreservation methods are routinely used: slow-freezing or vitrification. Slow-freezing allows for freezing to occur at a sufficiently slow rate to permit adequate cellular dehydration while minimizing intracellular ice formation. Vitrification allows the solidification of the cell(s) and of the extracellular milieu into a glass-like state without the formation of ice.OBJECTIVE AND RATIONALEThe objective of our study was to provide a systematic review and meta-analysis of clinical outcomes following slow-freezing/thawing versus vitrification/warming of oocytes and embryos and to inform the development of World Health Organization guidance on the most effective cryopreservation method.SEARCH METHODSA Medline search was performed from 1966 to 1 August 2016 using the following search terms: (Oocyte(s) [tiab] OR (Pronuclear[tiab] OR Embryo[tiab] OR Blastocyst[tiab]) AND (vitrification[tiab] OR freezing[tiab] OR freeze[tiab]) AND (pregnancy[tiab] OR birth[tiab] OR clinical[tiab]). Queries were limited to those involving humans. RCTs and cohort studies that were published in full-length were considered eligible. Each reference was reviewed for relevance and only primary evidence and relevant articles from the bibliographies of included articles were considered. References were included if they reported cryosurvival rate, clinical pregnancy rate (CPR), live-birth rate (LBR) or delivery rate for slow-frozen or vitrified human oocytes or embryos. A meta-analysis was performed using a random effects model to calculate relative risk ratios (RR) and 95% CI.OUTCOMESOne RCT study comparing slow-freezing versus vitrification of oocytes was included. Vitrification was associated with increased ongoing CPR per cycle (RR = 2.81, 95% CI: 1.05–7.51; P = 0.039; 48 and 30 cycles, respectively, per transfer (RR = 1.81, 95% CI 0.71–4.67; P = 0.214; 47 and 19 transfers) and per warmed/thawed oocyte (RR = 1.14, 95% CI: 1.02–1.28; P = 0.018; 260 and 238 oocytes). One RCT comparing vitrification versus fresh oocytes was analysed. In vitrification and fresh cycles, respectively, no evidence for a difference in ongoing CPR per randomized woman (RR = 1.03, 95% CI: 0.87–1.21; P = 0.744, 300 women in each group), per cycle (RR = 1.01, 95% CI: 0.86–1.18; P = 0.934; 267 versus 259 cycles) and per oocyte utilized (RR = 1.02, 95% CI: 0.82–1.26; P = 0.873; 3286 versus 3185 oocytes) was reported. Findings were consistent with relevant cohort studies.Of the seven RCTs on embryo cryopreservation identified, three met the inclusion criteria (638 warming/thawing cycles at cleavage and blastocyst stage), none of which involved pronuclear-stage embryos. A higher CPR per cycle was noted with embryo vitrification compared with slow-freezing, though this was of borderline statistical significance (RR = 1.89, 95% CI: 1.00–3.59; P = 0.051...
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