Is the timing of implantation affected by zona pellucida micromanipulation?

Purpose: Our purpose was to examine the timing of implantation and early em bryo development following uterine transfer of oocytes/embryos previously s ubjected to zona pellucida micromanipulation. Methods: A total of 68 singleton pregnancies resulting from IVF and embryo transfer with/without micromanipulation. Patients were divided into four gr oups according to the type of micromanipulation technique: assisted hatchin g, embryo biopsy, intracytoplasmic sperm injection, and no micromanipulatio n (control group). Serial serum beta-hCG levels were measured between 10 an d 25 days after fertilization and log-transformed. Linear regression analys es were performed and extrapolated to hCG = 10 mIU/ml (hCG(10)) to estimate detectable implantation. The slopes of the regression lines were used to e stimate the rising speed of hCG, an indirect sign of embryo development. Results: There were no significant differences among groups with respect to hCG(10), the slopes or intercepts of the regression lines. Conclusions: Various oocyte/embryo microsurgical procedures used in ART inv olving zona pellucida manipulation do not appear to affect the timing of im plantation or early embryo development.