The value of HCG serum concentrations after trigger in predicting pregnancy and live birth rates in IVF–ICSI

The aim of this study was to determine if an association existed between serum human chorionic gonadotrophin (HCG) level at 12 h after trigger and IVF and intracytoplasmic sperm (ICSI) treatment outcomes. Women undergoing initial IVF–ICSI and embryo transfer treatment using the long luteal phase gonadotrophin-releasing hormone agonist protocol between April 2012 and March 2013 for tubal factor were included (n = 699). In the clinical pregnancy group, HCG after trigger was significantly elevated (276.0 ± 5.1 versus 198.5 ± 6.1 mIU/mL; P < 0.001). The optimal cut-off value proposed by the receiver operating characteristic analysis (area under curve = 0.730) for HCG was 201.2 mIU/ml. Compared with the lower HCG group, the clinical pregnancy rate in the higher HCG group was increased in obese and non-obese patients (77.8% versus 57.3%, P < 0.05; 85.6% versus 53.0%, P < 0.01, respectively). Adjusted for age and body mass index, an increase of HCG was associated with a better IVF–ICSI treatment outcome (OR 4.39, 95% CI 2.99 to 6.45). Clinical pregnancy rate was significantly higher across increasing quartiles of HCG. An elevated level of serum HCG at 12 h after trigger was associated with a better IVF–ICSI outcome.