Your doctor also may recommend one or a combination of these additional assisted reproductive technologies to enhance your IVF treatment.
For an embryo to implant in the uterus, it first must “hatch” from its surrounding membrane. A reproductive specialist can assist this process using a chemical solution or laser. Performed just before in vitro fertilization, this procedure can improve the odds of a successful implantation, especially for older women, frozen embryos, embryos with thickened cell walls or in couples where prior IVF attempts have proved unsuccessful.
In some cases, embryos can grow in the laboratory until the blastocyst stage, which typically occurs five to six days after egg retrieval. This is done to allow for genetic testing of the eggs, to identify the eggs most likely to implant and to allow doctors to implant fewer embryos to lower the likelihood of multiple births.
Cryopreservation and Frozen Embryo Transfer (FET)
If you have more embryos than needed for a single IVF transfer, you can freeze them, a process called cryopreservation. This provides another chance for pregnancy, through a Frozen Embryo Transfer (FET), without undergoing another ovarian stimulation and retrieval. Frozen embryos of good quality have 90 to 95 percent survival rates and can be frozen indefinitely. See “How Fertility Preservation Works” for more information.
Intracytoplasmic Sperm Injection (ICSI)
In cases of severe male infertility, this technique directly injects single sperm into the egg in a laboratory setting to achieve fertilization. Injected eggs are then used as part of conventional in vitro fertilization.
Preimplantation Genetic Screening and Diagnosis
Comprehensive Chromosomal Screening, or CCS (previously known as Preimplantation Genetic Screening, or PGS) and Preimplantation Genetic Diagnosis (PGD) make genetic screening possible before implanting an embryo. After egg retrieval and three to five days of embryo development, specially trained lab technicians remove one or two cells and test the DNA material for a variety of inherited and chromosomal factors. Unaffected embryos are then selected for transfer to the uterus.
Sperm Chromatin Structure Assay (SCSA)
A male may have a good sperm count, good sperm motility and normal sperm shape, but still exhibit small breaks in the sperm chromosomes, which may contribute to fertility problems. Using special stains and highly technical instrumentation, SCSA can distinguish normal sperm from those with fragmentation in their DNA.
Surgical Sperm Retrieval
When a man’s sperm cannot move through his genital tract because of blockage, TESE or MESA procedures can help. Usually performed by a urologist while the woman is undergoing IVF, Testicular Sperm Extraction (TESE) involves aspirating the sperm directly from the testes or from a testicular biopsy. Microsurgical Epididymal Sperm Aspiration (MESA) involves aspirating sperm from the epididymus, the tubes next to the testicles that collect sperm.
Zygote Intrafallopian Transfer (ZIFT), Tubal Embryo Transfer (TET) and Famete Intrafallopian Transfer (GIFT)
As with IVF, the ZIFT and TET processes combine the eggs and sperm in the laboratory for fertilization. With IVF, the fertilized embryo is transferred into the uterus; with ZIFT and TET, it is transferred to the fallopian tube.
With GIFT, the doctor transfers sperm and eggs into the fallopian tubes immediately after egg retrieval, using laparoscopy under general anesthesia. Fertilization thus occurs in the body, rather than in the laboratory. You may choose to use GIFT for religious reasons that prohibit fertilization outside the body.