The impact of serum homocysteine levels in women and men on pregnancy outcomes in fresh IVF/ICSI cycles: A retrospective cohort study

Abstract

Background

High serum homocysteine (Hcy) levels are associated with reduced fertility and adverse pregnancy outcomes. Previous studies have produced inconsistent results regarding the influence of Hcy levels on in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) outcomes. Moreover, most existing studies have predominantly focused on Hcy levels in women, with limited attention given to serum Hcy levels in men.

Methods

This retrospective cohort study was conducted at the Reproductive Center of Xi’an People’s Hospital (Xi’an Fourth Hospital) from October 2021 to October 2023, involving a total of 481 patients who underwent fresh embryo transfer. Male and female patients were grouped according to quartiles of serum Hcy concentration. Of these, 290 patients achieved pregnancy, while 191 did not. Follow-up data showed that 250 patients maintained their pregnancies to 12 weeks, while 40 experienced early miscarriage. Pregnancy outcomes were analyzed for all patients and for clinically pregnant women who were followed up to 12 weeks, with a focus on factors associated with early miscarriage.

Results

The results demonstrated that the pregnancy rate with female serum Hcy concentrations ≥ 12.43 µmol/L was significantly lower than in those with Hcy concentrations < 8.07 µmol/L (P = 0.006) and 8.07–9.57 µmol/L (P = 0.008). Female serum Hcy ≥ 12.43 µmol/L was identified as an independent risk factor for early miscarriage (OR = 2.20, 95 % CI 1.24–3.88). No significant correlation was observed between female serum Hcy levels and embryo quality. Additionally, there was no significant association between male serum Hcy levels and clinical pregnancy, pregnancy outcomes, or embryo quality. Among the 250 cases of clinical pregnancy, 97.6 % (244 cases) resulted in successful live births, while 2.4 % (6 cases) did not result in live births. Non-live birth cases were primarily attributed to factors such as premature rupture of membranes, cervical insufficiency, oligohydramnios, fetal abnormalities, and other causes.

Conclusion

Elevated serum Hcy concentrations in women adversely affected clinical pregnancy and early miscarriage (≥12.43 µmol/L), while male serum Hcy did not show a significant effect. The inclusion of Hcy levels in both men and women provides a more comprehensive perspective for exploring multidimensional factors influencing fertility outcomes.