P-147 Number of autologous mature oocytes as a predictor of live birth rate in women aged over 40 who do not accept egg donation
Authors: Guidobono M , Tiveron M , Castro A , Zappacosta Villarroel M  P , Lorenzo F , Viglierchio M  I , Valcarcel A 
Published: July 2024

Study question

Is the number of mature oocytes (M2) retrieved a reliable predictor of success for women aged over 40 with autologous oocytes?

Summary answer

79.5% of live births were achieved in patients with ≥3M2 retrieved, 14.3% in women with 2M2, and 6.5% in women with 1M2.

What is known already

The delayed desire for parenthood has become a social phenomenon, particularly among women over 35. Reproductive outcomes in women over 40, using their own oocytes, are usually poor due to a decrease in follicle and oocyte quantity and quality, along with an increased prevalence of oocyte chromosomal abnormalities. While using donated oocytes is often recommended, it remains an unacceptable option for many couples. Furthermore, in Argentina the legislation on Assisted Reproduction Technologies endorses assisted reproductive treatments employing womeńs own oocytes up to the age of forty-four.

Study design, size, duration

This retrospective observational study, was performed between January 2004 and December 2022 in 5757 patients aged 40 and above undergoing autologous oocyte retrieval and fresh embryo transfer because they do not accept PGTa.

Statistical analysis was performed using the InStat GraphPad statistical package. One-way ANOVA and two-tailed Student’s t-test were performed as required.

Participants/materials, setting, methods

Group1(G1): 40 years (N = 1600); Group 2(G2): 41years (N = 1300); Group 3(G3): 42 years (N = 1087); Group 4(G4): 43 years (N = 735); Group 5(G5): 44 years (N = 496); Group 6(G6): 45 years (N = 302); Group 7(G7): 46 years (N = 140); Group 8(G8): 47 years (N = 61); Group 9(G9): 48 years (N = 23); Group 10(G10): 49 years (N = 13). Primary outcome was relationship between number of M2 and live birth rate. Secondary outcomes were live birth rate, cancellation rate, miscarriage rate, clinical pregnancy rate.

Main results and the role of chance

Number of M2 retrieved: G1=3.9±3.4 [1-16]; G2=3.6±2.7 [1-14]; G3= 3.5±2.3 [1-12]; G4= 3.4±2.8 [1-14], G5=2.5±1.5 [1-7]; G6=2.3±2.2 [1-12]; G7=1.8±1.5 [1-8]; G8=1.5±0.9 [1-3]; G9=1.3±0.6 [1-3]; G10=1.0±0 [1-1].

Cancelation rate (%): G1=18.2 (292/1600); G2=20.9(272/1300), G3=22.3(243/1087); Gr4= 29.9(220/735); G5=28.0(139/496); G6=38.1 (115/302); G7= 42.8(60/140); G8= 44.3 (27/61); G9=47.8 (11/23); G10= 61.5 (8/13).

Clinical pregnancy/transfer rate(%): G1=24.2 (316/1308); G2=21.7 (223/1028); G3=18.0(152/844); G4=18.0 (93/515); G5=9.2 (33/357); G6=11.2 (21/187); G7=3.7 (3/80); G8=0 (0/34); G9=8.3 (1/12); G10=0 (0/5).

Live birth rate (%): G1= 11.8 (147/1250); G2= 10.0 (99/993); G3= 6.8 (57/831); G4= 6.6 (34/515); G5= 3.2 (11/348); G6= 2.1 (4/187); G7= 1.2 (1/80); G8= 0 (0/34); G9=0 (0/12); G10=0 (0/5).

Miscarriage rate (%) 40 to 46 years: G1= 43.0 (111/258); G2= 47.3 (89/188); G3= 59.0 (82/139); G4= 63.4 (59/93); G5= 66.7 (22/33); G6= 80.9 (17/21); G7=66.7 (2/3) and 100 (1/1) for 48 years (G9).

Cancellation rates increased with age. The number of M2 retrieved was significantly associated with clinical pregnancy, live birth and miscarriage rates.

The average number of mature oocytes retrieved in cases resulting in live births was consistently higher across all age groups: G1=5.8±2.7 [1-16]***; G2= 4.8±3.5 [1-14]***; G3= 4.0±2.1 [1-9]***; G4= 5.7±2.7 [3-13]***; G5= 4.2±1.4 [2-7]***; G7= 6.0±1.4 [5-8]***; G8= 7.0±0 [7,7]*** (***= p &lt; 0.0001).

Limitations, reasons for caution

This extensive retrospective study’s conclusions should be cautiously applied, limited to a specific group of elderly women unwilling to consider egg donation.

106 clinical pregnancies were not included because we did not have information on live births.

Wider implications of the findings

Identifying parameters associated with higher live birth rates in this population may aid in providing realistic expectations for achieving pregnancy with autologous oocytes. This information could guide medical advice and potentially suggest alternative options, such as egg donation or adoption.

Trial registration number

NOT APPLICABLE