P-109 Non-invasive Genetic Testing (niPGTA) and Laser Assisted Hatching (LAH) may improve pregnancy and ongoing pregnancy rates in patients of advanced maternal age

Abstract

Study question

Does niPGTA and LAH improve pregnancy and ongoing pregnancy rates in patients of advanced maternal age?

Summary answer

niPGTA increases pregnancy and clinical pregnancy rates in patients aged ≥38 years compared to those without tested embryos, while LAH may further improve pregnancy outcomes.

What is known already

Embryos release cell-free DNA (cf-DNA) in the IVF culture media, which can be analyzed for chromosomal constitution. The benefit that niPGTA holds over PGT-A is that it is a non-invasive test and could potentially produce comparable results. Therefore, the time to pregnancy and the risk of miscarriage could be reduced in comparison to an IVF treatment with non-tested embryos. Previous studies have shown high concordance with trophectoderm biopsies in PGT-A patients and improved outcomes with LAH in frozen-thawed cycles. However, there is a lack of studies investigating clinical pregnancy rates with niPGTA.

Study design, size, duration

Retrospective cohort study including 74 patients aged ≥38 years, who underwent Single Frozen Embryo Transfer (FET) from May 2021 to February 2023. Patients who had Endometrial Receptivity Assay (ERA) were excluded.

Participants/materials, setting, methods

32 couples had niPGTA; Spent Blastocyst Media (SBM) for each blastocyst were collected on Day 6 and analyzed using the EMBRACE test. Embryos were vitrified. 42 couples had their blastocysts vitrified on Day 5/6 without testing. LAH was introduced to all patients in October 2021. Before that, no LAH was performed. Embryos were transferred to patients 2 hours post-warming after LAH. Pregnancy test was performed 10 days after FET and clinical pregnancy was established.

Main results and the role of chance

There was a statistical significant increase of pregnancy rate (p = 0.017, Pearson’s Chi-Squared test) and a trend towards higher clinical pregnancy rate for niPGTA patients versus those who had a transfer of not tested embryos. Regarding LAH, there was a trend towards higher pregnancy and clinical pregnancy rates in both niPGTA and not tested group. Results for pregnancies and clinical pregnancies are presented in Table 1.

Table 1:

P-109

	Overall niPGTA	Overall NOT TESTED	niPGTA with LAH	niPGTA without LAH	Not Tested with LAH	Not Tested without LAH
Number of patients	32	42	17	15	20	22
Pregnancy (%)	22 (68.75)	16 (38.10)*	13 (76.47)	9 (60.00)	8 (40.00)	8 (36.36)
Clinical Pregnancy (%)	15 (46.88)	15 (35.71)	9 (52.94)	6 (40.00)	8 (40.00)	7 (31.82)

*

p = 0.017

Limitations, reasons for caution

More patients are required to confirm clinical significance of pregnancy and clinical pregnancy rates of niPGTA over not tested embryos and if LAH can improve the outcomes. A review of patients who had previous implantation failures and miscarriages in addition to ERA could yield clearer conclusions.

Wider implications of the findings

The results of this study are encouraging for niPGTA combined with LAH for patients aged ≥38 years. Further studies on niPGTA and modifications of the protocol for increased concordance rates and shorter time in embryo culture should be explored.

Trial registration number

Not applicable