Factors affecting the successful embryo transfer

The main factors affecting pregnancy and implantation rates are uterine receptivity, embryo quality, and transfer efficiency. Embryo transfer (ET) is the last step of critically important procedure of in vitro fertilization (IVF) and probably the least successful step in Assisted Reproductive Technology (ART) treatment cascade; though simple in most of the cases, it may pose to be the most difficult in some. No matter how good the IVF laboratory culture environment is, the physician can ruin everything with a carelessly performed embryo transfer. The entire IVF cycle depends on delicate placement of the embryos at the proper location near the middle of the endometrial cavity. Pregnancy rates will be significantly increased with the following procedures: 1. Trial transfer 2. Avoiding the initiation of uterine contractility by using soft catheters, gentle manipulation and by avoiding touching the fundus. 3. Removal of cervical mucus, wash and lavage of cervix with culture media. 4. Ultrasound-guided ET with full bladder. 5. Deposition of the embryo 2 cm below the uterine fundus. 6. Examination of catheter following transfer for retained embryos, blood and mucus. Slow withdrawal of the embryo transfer catheter, the use of a fibrin sealant, bed rest after embryo transfer, sexual intercourse and routine administration of antibiotics following embryo transfer remained to be studied by randomized clinical trials (RCTs).