"Embryo Transfer Strategies: Cleavage vs. Blastocyst" Brief overview of the significance of embryo transfer in assisted reproductive technologies (ART) and the focus on cleavage and blastocyst stages with their merits and demerits.

1. CLEAVAGE OR
BLASTOCYST
EMBRYO
TRANSFER
Is the Debate Over?
Dr Kaberi Banerjee

2. Pros & Cons

3. < 4 E M B RY O S
C L E AVA G E B E T T E R
C L E AVA G E B E T T E R
I N Y O U N G E R
B L A S TO C Y S T N O T
S I G N I F I C A N T LY
B E T T E R

4. stage. It could be argued that the type of culture media used
in extended culture could be responsible for large for gesta-
tional age babies; however, a recent study seems to refute
this (De Vos et al., 2015).
Congenital anomalies
A recent meta-analysis (Dar et al., 2014) reported that the
odds of congenital anomalies were significantly higher for
babies born after embryo transfer at blastocyst stage com-
pared with those born after embryo transfer at cleavage stage
(1.29, 95% CI 1.03 to 1.62).
culture?
Despite the concerns highlighted above (Figure 1), exte
ing culture to blastocyst stage seems to be the preferred st
egy among many IVF clinics, and its popularity has gro
exponentially in recent years. The key drivers for this
proach are the importance clinics, commissioners and
tients attach to the realization of short-term goals (hig
pregnancy rates per embryo transfer episode) and their
sition in national league tables based on success rates. T
is mainly due to the fact that single embryo transfer at b
tocyst stage leads to a significantly higher pregnancy rate
embryo transfer compared with those at cleavage stage
Factors favouring
blastocyst stage
embryo transfer
Factors favouring
cleavage stage
embryo transfer
Figure 1 Balance between blastocyst and cleavage stage embryo transfer.

6.  Low quality evidence that
Blastocyst transfer may be
associated with higher live birth
rates than Cleavage stage.
 No evidence of a difference
between the groups in
Cumulative Pregnancy rates
 Further RCTs are needed

7. • Burden of additional transfer of
Cleavage Stage Embryos
• Cost of more embryos to freeze in
Cleavage Stage
• Burden of additional oocyte pick
up if no embryo formed or to
freeze in Blastocyst Transfer
• Cost of extended culture and
vitrification of Blastocyst
Fertil Steril 2016

8. Extended embryo culture to the
blastocyst stage has the
potential to compromise
obstetric and perinatal
outcomes as increased rate of
placenta praevia and preterm
delivery in fresh cycles.

9. • Good for good prognosis
• Not always for recurrant
implantation failure and those
with fewer embryos
• Pregnancy rate/started cycle
may be low
• Cancelled Transfers Increase
• Can we predict blastulation
rate?
• Excellent Laboratory and Skill
set
• Excellent Cryopreservation
Unit
• May have fewer/no embryos
to transfer
Fertil Steril,2018

11. Blastocyst vs
Cleavge
The Debate is
Ongoing!
Thank You!