Association between pre-pregnancy cardiovascular health and singleton birthweight after in vitro fertilization/intracytoplasmic sperm injection: A retrospective cohort study.

OBJECTIVE

This study explores the association between maternal pre-pregnancy cardiovascular health (CVH) and singleton birthweight after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) cycles.

METHODS

This retrospective cohort study included 3407 women with live singleton births after their first IVF/ICSI cycle (2019-2023) at the Center for Reproductive Medicine affiliated to Shandong University. Birthweight outcomes included very low birthweight (VLBW), low birthweight (LBW), normal birthweight (NBW), macrosomia, large for gestational age (LGA), very LGA, appropriate for gestational age (AGA), small for gestational age (SGA), and very SGA.

RESULTS

A higher maternal pre-pregnancy CVH score was associated with a lower risk of both decreased neonatal birthweight (per 10-point increase: VLBW, adjusted odds ratio [aOR] = 0.68, 95% confidence interval [CI] 0.51-0.91, false discovery rate [FDR] q = 0.01; LBW, aOR = 0.85, 95% CI 0.76-0.95, FDR q = 0.009) and increased neonatal birthweight (macrosomia, aOR = 0.82, 95% CI 0.76-0.88; LGA, aOR = 0.79, 95% CI 0.74-0.83; very LGA, aOR = 0.74, 95% CI 0.69-0.80; all FDR q < 0.001). A higher maternal CVH score was also associated with an increased likelihood of NBW (aOR = 1.23, 95% CI 1.15-1.32, FDR q < 0.001) and AGA (aOR = 1.23, 95%CI 1.16-1.30, FDR q < 0.001) in the offspring. Population-attributable fraction estimates showed that 12.8%-45.8% of abnormal birthweight could be attributed to low-moderate CVH (score < 80), with VLBW (45.8%) and very LGA (19.8%) being the most affected. Among the four CVH components (body mass index, blood pressure, glucose, lipids), elevated body mass index (≥23.0 kg/m2) was the strongest contributor to abnormal birthweight.

CONCLUSION

Better maternal pre-pregnancy CVH is associated with more favorable neonatal birthweight outcomes after IVF/ICSI. Improving maternal CVH, particularly BMI, might reduce the risk of abnormal birthweight and improve assisted reproductive technology outcomes. These findings have implications for clinical practice in terms of pre-pregnancy health management.