Reproductive biology
Discover in depth the biological processes related to fertilization, embryo implantation and all aspects affecting human reproductive biology.
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How are seminograms interpreted?
A seminogram, or semen analysis, is a basic analysis of a semen sample with the aim of determining semen quality. In order to carry out the analysis correctly, the patient needs to refrain from sexual intercourse for […]
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Oligozoospermia and criptozoospermia
Oligozoospermia is the presence of an abnormally low number of sperm in a semen sample. According to the criteria in the 5th edition of the World Health Organisation (WHO) manual, normal sperm content in a sample […]
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A boy or a girl: can I choose my baby’s gender?
Whilst it is technically possible to choose a child’s gender using pre-implantation genetic diagnosis, Spanish law prohibits selecting a baby’s sex, except with a view to avoiding the transmission of genetic diseases associated with the X chromosome. […]
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Techniques for obtaining spermatozoa
There are currently many different solutions when spermatozoa are not present in ejaculate. Access to a trained urologist increases chances of achieving spermatozoa in greater quantities and with improved quality. What is TESA (Testicular Sperm Aspiration)? This […]
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ACCESS INFORMATION PRIOR TO THIS POST ON BETA β-hCG (human chorionic gonadotropin) is a glycoprotein that is initially secreted by trophoblast cells in the embryo shortly after it implants in the uterus. The rapid increase […]
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Embryo transfer on day 3 or day 5. The pros and cons.
Determining the ideal day for embryo transfer has always been a controversial issue and there are, even today, still a number of doubts surrounding this issue. Embryo culture is, basically, a selection process. Each embryo’s […]
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Obesity and embryo implantation failure
It has long been known that patients who are overweight face increased reproduction and pregnancy loss issues. Issues achieving a successful pregnancy are even greater if, as well as being obese, the patient also has […]
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Recurrent pregnancy loss: an issue that does have a solution
Clearly one of the most difficult situations a couple trying for children may have to face is pregnancy loss. Suffering is even greater when, prior to this, the couple has gone through fertility treatment such […]
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What does embryo biopsy involve?
Preimplantation Genetic Diagnosis (PGD) is a tool designed to “get to know” the embryos genetically before they are transferred into the mother’s uterus. Thanks to this technique, we can study their chromosome count and find […]
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Why does the PGT-A preimplantation genetic test (PGT) decrease the miscarriage rate?
La tasa de aborto en la población general sin problemas de fertilidad se encuentra en torno a un 15-20%, es decir una de cada cinco parejas que consiguen embarazo tendrá un aborto espontáneo, y en […]