Symmetry in number of retrieved oocytes between two ovaries: a possible predictor of in vitro fertilization outcome

Abstract

Objective. To examine the relationship between the ratio of difference in number of retrieved oocytes from the two ovaries to total number of oocytes (difference ratio, |N_RO−N_LO|/N_TOTAL) and in vitro fertilization (IVF) outcome.

Methods. Retrospective review of medical record for infertility patients with intact two ovaries who had undertaken controlled ovarian stimulation (COS) and IVF cycles in Seoul National University Hospital was conducted. Characteristics and IVF outcomes were compared according to the difference ratio (|N_RO−N_LO|/N_TOTAL) using student t-test and χ² test. To adjust for the effect of confounding factors, binary logistic regression test was performed.

Results. When the study population was divided according to the difference ratio by cut-off value of 0.4, patients with difference ratio less than 0.4 showed significantly higher pregnancy rate (25.7% vs. 17.1%, p = 0.021). A significant correlation was noted between the difference ratio and achievement of pregnancy after adjustment for patient's age and total number of top quality embryos transferred (adjusted OR = 0.40, 95% CI 0.19–0.83, p = 0.014).

Conclusions. The difference ratio of retrieved oocytes in patients with intact two ovaries was observed to have prognostic value in IVF cycles.

Keywords:

• Symmetry
• oocyte
• ovary
• in vitro fertilization

Acknowledgements

The authors would like to express their deepest gratitude to Sun Kyung Oh, Hee Sun Kim, Moon Ju Kang, Sung Ah Kim for their laboratory and statistical support of this study.

Declaration of interest: This study was supported by a grant of the Korea Health 21 R&D Project, Ministry of Health & Welfare, Republic of Korea (01-PJ10-PG6-01GN13-0002).