The document critiques preimplantation genetic testing for aneuploidies (PGTA) in IVF, highlighting its high costs and lack of proven benefits on overall pregnancy outcomes. Studies, including the STAR study, show that while some subgroups may experience slight benefits, overall results do not support routine clinical use of PGTA, especially given the risks of sampling errors and potential harm to embryos. It argues for PGTA to be considered an experimental procedure rather than a standard practice.

1. Pitfalls of
PGTa
Dr Kaberi Banerjee

2. WHAT IS PGS WHAT IS PGTA PROBLEMS
WITH PGTA
VARIOUS
STUDIES

3. The Earlier
names of
Genetic Tests
on Embryos

4. Current names of Genetic Tests on the
Embryo

5. PGTa claims to reduce
implantation failure in IVF and
reduce the risk of miscarriages.
It is a very expensive test!
Is it true?

7. Some Facts of
PGTa
• All cells in any embryo doesn’t
demonstrate aneuploidies i.e
chromosomal abnormalities.
There are only small number of
cells which shows abnormalities.
If embryo biopsy shows abnormal
DNA, it is not the whole cell will
be abnormal.

8. Some Facts of
PGTa
• It is also observed that abnormal cells
often self-destruct and some cells self-
correct by themselves. This self-correction
happens more in cells which makes baby
than the cells which makes placenta
(trophectoderm). For PGT-a, embryo
biopsy is taken from trophectoderm. This
shows that there is no benefit of doing
blastocyst stage embryo biopsy as cells
which are tested are of outer layer not the
inner layer which forms the baby.

9. Overall same , but can show as 50% and 100%
Depends which data you want to show!
Non PGS-50%?
10
8
6
4
2+2
-ve/+ve
PGS-100%?
10
8
6
4
2
+ve
Extra Cost
Freezing
Transfer Time
Extra Cost
PGS
Personnel
Laboratory
WaitingTime

10. The STAR Study
• A total of 661 women (average age 33.7
± 3.6 years) were randomized to PGT-A (n
= 330) or morphology alone (n = 331).
• PGT-A did not improve overall
pregnancy outcomes in all women, as
analyzed per embryo transfer or per ITT.
There was a significant increase in OPR
per embryo transfer with the use of PGT-
A in the subgroup of women aged 35-40
years who had two or more embryos that
could be biopsied, but this was not
significant when analyzed by ITT.

11. • The STAR study thus reveals that
PGT-A does not beneficially affect
IVF outcomes in confirmation of
another relatively recent study in
women 37 years and older by Kang
et al. Like the STAR study, Kang et
al. reported seemingly improved
live birth rates following PGT-A but
this outcome advantage, actually,
reversed itself after correct intent-
to-treat analysis of outcomes with
reference cycle start: Pregnancy as
well as live birth rates, indeed,
ended up to be significantly higher
in control non-PGT-A patients (49.5
vs 21.5% and 39.8 vs 19.9%).
• Considering all presented
evidence here, it is difficult to
understand what further argument
can be made for the continuous
routine clinical utilization of PGT-A
to improve IVF outcomes.
•

12. • Errors may occur during the genetic analysis of the small
amount of DNA collected.
• Mitotic mosaicism may lead to sampling errors
• Some normal embryos will be discarded, leading to an
overall decrease in the cumulative pregnancy rate
achievable by the eventual transfer of all embryos in the
cohort.
• Real possibility of damage to the blastocyst as result of the
trophectoderm biopsy.
• No studies have addressed the impact of trophectoderm
biopsy in embryos with less than ideal morphologic
characteristics, in older patients, or after an intervening
cryopreservation procedure.

13. Assumptions
• Blastulation Rate- 47%
• Aneuploidy Rate- 59%
• IR-D3 21-50%,
• Non PGS D5 38-47%,
• PGS D5 39-65%
• Mosaicism and Technical
Errors reduce LBR

16. • Any Intervention that claims to
increase the pregnancy rate in IVF
must stand the test of time…till
then must be clearly offered as an
experimental test and at least
should not financially drain the
patient.