Association Between Body Mass Index and Reproductive Outcomes in IVF Cycles: A Retrospective Analysis from an Ecuadorian Cohort

Authors

  • José Augusto Durán Chávez
  • Pablo Andrés Yánez Marcayata
  • David Rafael Hidalgo Timbiano
  • Héctor Rodrigo Remache Cevallos
  • Luis Francisco Rodas Fajardo
  • Wilson Hernan Mereci Becerra

Keywords:

Overweight, body mass index, in vitro fertilization, pregnancy rate, blastocyst development

Abstract

Objective: To study whether overweight is associated with lower pregnancy success in women undergoing conventional in vitro fertilization.

Design: Retrospective cross-sectional observational study.

Subjects: Thirty-seven women who underwent conventional in vitro fertilization at the PROVIDA Assisted Reproduction Centre in Latacunga, Ecuador, from January 2022 to June 2024.

Exposure: Body mass index category, comparing normal weight (<25 kg/m²) with overweight or obesity (≥25 kg/m²).

Main Outcome Measures: Pregnancy rate, number of oocytes retrieved, number of follicles, and number of day-5 blastocysts.

Results: Twenty-two women (59.5%) had body mass index ≥25 kg/m² and 15 (40.5%) had body mass index <25 kg/m². The overall pregnancy rate was 56.8%. Pregnancy rate differed significantly by body mass index category (p=0.002), with higher pregnancy rates in women with body mass index <25 kg/m² than in women with body mass index ≥25 kg/m². Body mass index was moderately and negatively correlated with the number of day-5 blastocysts (r=-0.367; p=0.026). The number of blastocysts was positively correlated with pregnancy rate (r=0.339; p=0.040).

Conclusion: Overweight and obesity were associated with lower pregnancy success and fewer day-5 blastocysts in women undergoing conventional in vitro fertilization. Preconception weight management may improve reproductive outcomes, although larger multicenter studies are needed..

 

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Published

2026-05-15

How to Cite

1.
Durán Chávez JA, Yánez Marcayata PA, Hidalgo Timbiano DR, Remache Cevallos HR, Rodas Fajardo LF, Mereci Becerra WH. Association Between Body Mass Index and Reproductive Outcomes in IVF Cycles: A Retrospective Analysis from an Ecuadorian Cohort. J Neonatal Surg [Internet]. 2026 May 15 [cited 2026 May 15];15(1s):88-96. Available from: https://jneonatalsurg.com/index.php/jns/article/view/10291

Issue

Vol. 15 No. 1s (2026): Journal of Neonatal Surgery

Section

Original Article

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