Ongoing and cumulative pregnancy rate after cleavage-stage versus blastocyst-stage embryo transfer using vitrification for cryopreservation: Impact of age on the results

Abstract

Purpose To determine if blastocyst transfer increases the ongoing and cumulative pregnancy rates, compared with day 3 embryo transfer, in women of all ages when at least 4 zygotes are obtained. Methods Prospective study including patients undergoing a first IVF/ICSI treatment and assigned to cleavage stage (n= 46) or blastocyst (n=58) embryo transfer. Supernumerary embryos were vitrified and patients failing to achieve an ongoing pregnancy after fresh embryo transfer would go through cryopreserved cycles. The main outcome measure was the ongoing pregnancy rate after the fresh IVF/ICSI transfer and the cumulative ongoing pregnancy rate. Results were also analyzed according to age (under 35 and 35 or older). Results A majority of patients (96.6 %) had a blastocyst transfer when at least 4 zygotes were obtained. The ongoing pregnancy rate was significantly higher in the day-5 group compared with the day-3 group (43.1 % vs. 24 %, p=0.041). The cumulative ongoing pregnancy rate was higher (but not significantly) with blastocyst than with cleavage stage embryos (56.8 % vs. 43.4 %, p=0.174). When analysed by age, patients 35 or older showed significantly higher ongoing pregnancy rate (48.4 % vs. 19.3 %, p=0.016) and cumulative ongoing pregnancy rate (58 % vs. 25.8 %, p=0.01) in the day-5 group compared to the day-3 group, while no such differences were observed in women under 35. Conclusions Blastocyst transfer can be suggested whenever there are at least 4 zygotes. While there are no differences in women under 35, the benefit of this option over cleavage stage transfer could be significant in women 35 or older.

Blastocyst vs cleavage‐stage embryo transfer: systematic review and meta‐analysis of reproductive outcomes

“…The following subgroup analyses were performed for ongoing pregnancy/live birth: (1) number of embryos transferred (1; 2; > 2 allowed); (2) 38 Coskun (2000) 39 Emiliani (2003) 40 Fernández-Shaw (2015) 49 Hreinsson (2004) 41 Kolibianakis (2004) 43 Papanikolaou (2005) 46 Papanikolaou (2006) 45 Rienzi (2002) 47 Van der Auwera (2002) …”

“…Bungum (2003) 38 Coskun (2000) 39 Emiliani (2003) 40 Fernández-Shaw (2015) 49 Hreinsson (2004) 41 Kolibianakis (2004) 43 Montag (2006) 44 Kaur (2014) 42 Papanikolaou (2005) 46 Papanikolaou (2006) 45 Rienzi (2002) 47 Van der Auwera (2002) (low; atmospheric; unclear), (3) woman's age (mean age ≤ 33 years; unselected); (4) number and quality of available embryos at inclusion (at least four zygotes (day 1); at least three good-quality day 2 or 3 embryos; other studies). One additional subgroup analysis was performed stratifying studies that reported only ongoing pregnancy and those that reported live birth.…”

“…From the 33 potentially eligible studies, 21 were excluded: four because they were pseudorandomized [17][18][19][20] , nine because they were published only as abstracts [21][22][23][24][25][26][27][28][29] , seven because the embryo-transfer policy was different for the two study groups [30][31][32][33][34][35][36] and one because of inconsistent results 37 . The remaining 12 studies [38][39][40][41][42][43][44][45][46][47][48][49] , including 1200 women undergoing blastocyst transfer and 1218 undergoing cleavage-stage transfer, were included in this review.…”

“…Cumulative meta-analysis for ongoing pregnancy/live birth and for clinical pregnancy showed no clear trend regarding a change in the magnitude of effect over time ( Figures S1 and S2). Copyright 38 Fernández-Shaw (2015) 49 Kolibianakis (2004) 43 Van der Auwera (2002) 48 38 Fernández-Shaw (2015) 49 Kolibianakis (2004) …”

“…For the outcome of miscarriage, there was no important inconsistency; nevertheless, the serious imprecision observed led to the quality being downgraded by one level. For the proportion of women with surplus embryos cryopreserved, the quality of the evidence was downgraded two levels because of serious inconsistency; one study 49 reported that more embryos were cryopreserved in the blastocyst group. This finding appears to be at odds with the authors' claim that only 245/362 (68%) embryos reached blastocyst stage.…”