In-vitro Fertilization(IVF) | Biology for JAMB PDF Download

Definition

IVF is a technique in which fertilization occurs outside the human body, specifically in a laboratory setting. It involves the extraction of eggs from the female and the fertilization of those eggs with sperm in a laboratory dish.

Egg Retrieval

To initiate the IVF process, the woman undergoes hormonal stimulation to promote the development of multiple eggs within her ovaries. Once the eggs are mature, a medical procedure called egg retrieval or ovum pickup is performed under anesthesia to collect the eggs from the ovaries.

Sperm Collection

On the day of egg retrieval, a sperm sample is collected from the male partner. In some cases, donor sperm may be used if needed.

Fertilization

The collected eggs and sperm are combined in a specialized laboratory dish, where they are incubated for a few days to allow fertilization to occur. In some cases, a technique called intracytoplasmic sperm injection (ICSI) may be used, where a single sperm is directly injected into an egg to facilitate fertilization.

Embryo Development

After fertilization, the embryos are closely monitored in the laboratory for a few days to ensure their development. Typically, the most viable embryos are selected for transfer.

Embryo Transfer

Once the embryos have developed, one or more of them are transferred into the woman's uterus. This is done using a thin catheter, which is inserted through the cervix and into the uterus. The hope is that the transferred embryos will implant in the uterine lining and result in a successful pregnancy.

Cryopreservation

Any remaining viable embryos not transferred during the initial cycle can be cryopreserved (frozen) for future use. These frozen embryos can be thawed and transferred in subsequent cycles, eliminating the need for additional egg retrieval and fertilization procedures.

Pregnancy Testing

Approximately two weeks after the embryo transfer, a pregnancy test is conducted to determine if the IVF procedure was successful. If pregnancy occurs, further monitoring and care are provided to ensure a healthy pregnancy.

Success Rates

The success rates of IVF can vary depending on factors such as the age of the woman, the cause of infertility, and the quality of the embryos. It is important to note that IVF does not guarantee a successful pregnancy, and multiple cycles may be required in some cases.

Ethical Considerations

IVF raises ethical concerns regarding the status of embryos, multiple pregnancies, and the use of donor gametes. These ethical considerations are crucial in guiding the practice and regulation of IVF procedures.

It is important to consult up-to-date resources, textbooks, or reputable scientific sources for comprehensive and detailed information on IVF, as knowledge and advancements in this field continue to evolve over time.