P–614 BMI effects on oocyte quality in an egg donation program and the relationship with its first stimulation cycle
Authors: GALIND. MATEU N , Marti. Aldekoa I , Amoroch. Llanos B , Pére. Cano I , Leó. Rodríguez G , Gade. Navarro B , Martíne. Morales M D M , Muño. Cantero M 
Published: August 2021

Abstract

Study question
Does body mass index (BMI) affect oocyte quality in an egg donation program and its relationship with the first stimulation cycle?

Summary answer
Our results indicated significant differences within BMI groups obtaining better results in donors &lt;25 years old in quantity/quality oocyte than &gt; 25 with normal weight.

What is known already
Low weight (LW) and excess weight represent a risk factor for different pathologies and may have a negative effect on the quality of the ovarian response in infertility treatments.

Study design, size, duration
Observational retrospective study at IVI Alicante, in which first donor cycles between 01/01/2015 and 04/30/2020 were analyzed. 307 donors were included. Groups were divided according to the BMI following the WHO criteria and were subdivided according to the protocol used (antagonists / progestogens, age, previous pregnancy and polycystic ovary syndrome (PCOS)). In all cases, the number of total, MII and immature oocytes, doses of FSH and days of stimulation were observed.

Participants/materials, setting, methods
Donors between 18–35 years old, in their first stimulation cycle, were distributed according to their BMI, following the WHO criteria in kg / m2 (Low weight (LW): &lt;18, 5, Normal weight (NW): 18.5–24.9, Overweight (OW) 25–29.9 and Obese (O): ≥30).
Inclusion criteria: Good state of psychophysical health and normal tests according to Spanish law on ART .
Statistical analysis was performed with R statistical software, version 4.0, linear and establishing significant differences when p &lt; 0.05.

Main results and the role of chance
Taking into account the general results of the BMI groups by oocytes number and MII: LW: 19.2 / 14.9; NW: 20.2 / 15.6; OW: 18.9 / 14.6, p = 0.513 / p = 0.74 respectively, we observe that with BMI groups and progestin stimulation protocols, results are reversed: No. oocytes and MII with LW: 30 / 22.5; NW: 19.2 / 14.4, OW: 20.8 / 14.8 p = 0.402 / 0.662 respectively. LW and OW are conditions which affect more in quantity than oocyte quality. Significant differences in BMI are observed when they are subdivided according to age, obtaining better results in donors &lt;25 years of age both in quantity and oocyte quality than&gt; 25 years: Total oocytes: LW: 22.6, NW: 21.7, OW: 20 vs LW: 14.2, NW: 17.6, SP: 16.3, p = 0.01, respectively; No. of MII oocytes LW: 17.8, NW: 16.6, OW: 14.9 vs LW: 10.5, NW: 13.9 OW: 13.8, p = 0.003, respectively. Our results reflect that the NW group is the one with better results obtained compared to the LW and OW groups both in overall number of oocytes and also in quality. The type of stimulation does not affect this group of donors.

Limitations, reasons for caution
More studies with clear criteria and a uniform record of results are needed. Meanwhile, the proper shortlisting should be considered if it is a BMI of NW (18.5–24.9 kg / m2) and less than 25 years.
Wider implications of the findings: Analyzing other studies, there are disagreements in terms of discrimination of BMI groups and with incomplete data about of quantity, oocyte quality and oocyte stimulation, offering different results with the same parameters establishing trends in the NW group.

Trial registration number
Not applicable