IVF fails for a variety of reasons.
It's often difficult for patients to comprehend how IVF could fail when we collect eggs and sperm, combine them in a successful laboratory to generate embryos, then place what appear to be healthy dividing embryos into the uterus. Pregnancy is a complex process, as are most biological occurrences. What we don't know about pregnancy still outnumbers what we do.
Nonetheless, we have identified a number of specific characteristics that can lead to IVF failure on rare occasions.
IVF Failure: What
Causes It?
A healthy egg, normal, functional sperm, and a uterus capable of supporting the growth of a baby are the most crucial variables involved in a successful IVF cycle. Aside from these concerns, there are a slew of other factors that can influence one's chances of conceiving through IVF. The laboratory atmosphere, techniques employed in the lab, and the expertise of the professionals performing egg retrieval and embryo transfer are all factors to consider.
Anomalies of eggs
The human egg is an extremely intricate structure. As a result, it is vulnerable to damage, which could render it useless. Chromosomes (DNA packets containing your genes and those of your partner) double and line up in the middle of the cell when cells split, as you may recall from high school biology. Half of the chromosomes migrate in one direction when the cell divides, while the other half moves in the opposite direction, resulting in two identical cells. These chromosomes move because they are connected to the spindle apparatus, which is in charge of chromosome separation, which is required for cell division. The spindle machinery of the oocyte becomes more susceptible to breaking as it ages; this breakage can result in an aberrant chromosome distribution, resulting in a chromosomally disordered and thus nonviable embryo. The existence of free radicals, reactive oxygen species, and other metabolic products in the ovary as a woman ages can also cause damage to the oocyte. According to numerous recent research, between 25% and 40% of all oocytes have chromosomal abnormalities. As a lady gets older, this figure certainly rises.
Sperm with a defect
Although defective sperm tend to be a less common issue affecting IVF cycle success, they nonetheless serve an important supportive role. Fertilization does not occur simply because sperm collide with an egg. Instead, fertilisation is a complicated process in and of itself. Sperm must be motile in order to migrate to the egg; that is, the sperm's tail must be capable of propelling the sperm through the female reproductive canal to the egg. Sperm/egg interaction is enabled by specialised receptors on the surface of sperm heads that bind to specific receptors on the outer membrane of an egg. Once this occurs, the sperm head releases enzymes that allow the egg's outer membranes to be digested. After penetrating the egg, the sperm's nucleus opens, releasing the sperm DNA. The sperm and egg chromosomes unite at this point, resulting in a fertilised egg (which is actually a very early embryo). According to studies, chromosomal abnormalities in sperm are much more common than in eggs. Unlike chromosomally abnormal oocytes, which can result in chromosomally abnormal pregnancy, chromosomally aberrant sperm do not appear to be capable of fertilising an egg.
Intracytoplasmic sperm injection (ICSI) was created to help men with low sperm counts, low motility, or a small number of normal sperm fertilise and become pregnant. ICSI has progressed to the point where it is now commonly used in cases of severe male factor, with fertilisation rates comparable to those obtained with normal sperm. Furthermore, evidence from long-term research imply that the incidence of chromosomal abnormalities in the offspring of IVF cycles that included ICSI is not higher than in nature.
Deciding
which embryos to Transfer
The embryologist chooses the embryos that will be Transferred into the uterus of the woman. Unfortunately, our ability to tell the difference between chromosomally normal and chromosomally defective embryos is still severely limited. Our embryologist choose which embryos to transplant based on three factors: cell stage, embryo grade, and cell division rate for Day 3 Embryos and Expansion, Inner Cell Mass and Trophoblast cells for Day 5 / Blastocysts .
Similarly, we believe that higher-grade embryos (grade 1, 2, or even 2.5) are far more likely to implant than lower-quality embryos (3 or 4). Furthermore, our embryologists Dr. Sai can determine the pace of cell division because they see the embryos on a regular basis. An embryo that progressively reaches the 8 cell stage by day three, for example, has a significantly better chance of surviving than one that has delayed fertilisation
and experienced fast growth near the end of the time period.
Following failed treatment elsewhere. Following a review of their medical records, we may recommend a new stimulation regimen, a different IVF technique, the use of ICSI, or even pre-implantation genetic screening, or a donor gamete procedure. It's crucial to remember that different IVF clinics may approach the same patient in different ways, so failure at one facility doesn't have to imply you can't have a baby.
Need help in getting pregnant ? Please send me your medical details by filling in the form at www.drmalpani.com/free-second-opinion so that I can guide you !
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