1. Introduction
The success of in vitro fertilization (IVF) relies on a series of
crucial laboratory procedures, including the culture and development of
embryos in a controlled environment. However, despite strict quality
control, there is a risk of bacterial contamination during the embryo
culture process [1]. Such contamination poses a threat to the IVF
outcomes. Bacterial contamination in the IVF laboratory can arise from
various sources, including air, water, equipment, and personnel [2].
It can also occur at different stages of the IVF process, such as during
oocyte retrieval, sperm preparation, handling of culture dishes, or
manipulation of embryos. Bacteria introduced into the culture media can
proliferate rapidly, producing harmful byproducts and triggering
inflammatory responses that may negatively impact embryo development.
Additionally, certain bacteria may directly adhere to the embryo’s zona
pellucida, compromising its integrity and reducing the chances of
successful implantation.
Commonly, the washing technique is employed to rescue embryos that have
been contaminated. It involves the gentle removal of external
contaminants from the embryo’s surface. The washing process begins by
transferring the contaminated embryo to a clean petri dish containing a
culture media supplemented with antibiotics or antifungal agents. Gentle
swirling motions are then used to perform the washing. After that, the
embryo is transferred to a fresh, uncontaminated dish with a clean
culture medium. However, a study has demonstrated that washing alone is
not effective in eliminating bacteria, as some still remained in the
zona pellucida [3]. In a recent case report by Li R et al., a new
method was proposed to rescue contaminated embryos, involving the
removal of the contaminated zona pellucida using Tyrode acid [4]. It
has been observed that the porous structure of the zona pellucida makes
it difficult to completely eliminate microorganisms [5].
Additionally, the zona pellicida itself can prevent embryo development
in later stages [6]. Therefore, removing zona pellucida is a
promissing method to solve the contamination problems.
In our report, we describes an alternative method using laser to remove
the contaminated zona pellucida from an embryo. We present the clinical
details, procedural methodology, and subsequent outcomes of this unique
case, thereby shedding light on the promising prospects for assisted
reproductive technologies.