Single Embryo Transfer in Preimplantation Genetic Diagnosis (PGD)

Doron Goldberg Avi Tsafrir Naama Srebnik Rivka Farkash Eadit Buhbut Michael Gal Ehud J Margalioth Nava Dekel Gheona Altarescu Talia Eldar-Geva

IVF Unit and Department of Obstetrics and Gynecology, , Shaare Zedek Medical Center, Hebrew University School of Medicine,

Introduction

Twins and higher order pregnancies have more than doubled since fertility treatments have become available, resulting in a pre-term delivery epidemic. In the past decade, great effort was expended to reduce the rate of multiple pregnancies mainly by limiting the number of embryos transferred to the uterus during IVF treatments. Single embryo transfer (SET) has proven to be highly effective preventing iatrogenic twining.

Aim: To examine single embryo transfer policy in PGD patients.

Methods: Retrospective review of 1^st and 2^nd fresh PGD cycle in women younger than 30 years old between January 2010 and December 2012 in Shaare Zedek medical center (SZMC) PGD Unit. Comparison of elective SET (surplus embryos were cryopreserved) and double embryo transfer (DET). DET is allowed in PGD treatments from the first cycle according to IFA opinion paper 201 published in 2010. In order to minimize multiple pregnancies risk in SZMC PGD unit SET policy was implemented in young good prognosis patients.

Results: 49 women had an elective single embryo transfer and 47 had double embryo transfer. Results are shown in table 1 and table 2.

Table 1

	Mean age	1^ST cycle	oocytes	M2 oocytes	Cryopreserved embryos	Pregnancies/ Pregnancy rate
SET (N=49)	26.9	40 (81.6%)	22	17.9	5	21 42%
DET (N=47)	27.0	23 (48.9%)	18.9	15.8	2.3	22 46%
P-VALUE	0.8	0.01	0.03	0.09	<0.001	0.7

Table 2

	Deliveries/ Deliveries rate	Twins	C/S	Birth weigh	Gestational age
SET (N=49)	17 35%	0	0	3321±488	39.2
DET (N=47)	15 332%	5	5 3 (TWINS)	2970± 757	38.1
P-VALUE	0.8	0.03	0.01	0.1	0.1

Conclusion: Elective single embryo transfer following PGD resulted in the same delivery rate as DET with less twin pregnancies, lower c/s rate and higher birth weights. Since the aim of PGD is delivering healthy newborns, and multiple pregnancy does not serve that purpose, elective single embryo transfer to PGD patients should be considered over double embryo transfer in young good prognosis patients.