Comparison of aneuploidy for patients of different ages treated with progestin-primed ovarian stimulation or GnRH antagonist protocols.

Research Question: Does euploidy status differ among patients of different ages treated with progestin-primed ovarian stimulation (PPOS) or gonadotrophin releasing hormone antagonist (GnRH-a) protocols?

Design: Patients undergoing PGT-A (n = 418; 440 cycles) were enrolled and grouped according to female age (<35 years and ≥35 years). Protocols were as follows: PPOS: <35 years (n = 131; 137 cycles); ≥35 years (n = 72; 80 cycles); GnRH-a: <35 years (n = 149; 152 cycles); ≥35 years (n = 66; 71 cycles).

Results: For cycles treated with PPOS in the older group, rates of euploid blastocyst per metaphase Ⅱ oocyte (15.48% versus 10.47%) and per biopsied blastocyst (54.94% versus 40.88%) were significantly higher than those treated with GnRH-a (P < 0.05). The mosaic rate per biopsied blastocyst was significantly lower for cycles treated with PPOS than cycles treated with GnRH-a (8.64% versus 23.36%) (P < 0.001). In the younger group, no significant difference was found between treatments (P > 0.05). In older and younger groups, the drug to inhibit LH surge was cheaper for cycles treated with PPOS compared with GnRH-a (P < 0.001). Generalized estimation equations based on binomial distribution female age and euploidy rate was significantly negatively correlated for all participants (β -0.109, 95% CI -0.183 to -0.035, P = 0.004), and between GnRH-a protocol (reference: PPOS) and the euploidy rate in the older group (β -0.126, 95% CI -0.248 to -0.004, P = 0.042). Multiple logistic regression indicated that ovarian stimulation protocol was not associated with ongoing pregnancy rate (OR 0.652, 95% CI 0.358 to 1.177; P = 0.14).

Conclusions: PPOS is suitable for patients undergoing PGT-A, particularly older patients for the higher euploid blastocyst rate attained by PPOS protocol.