Human fertility at a crossroad.

Bart Cjm Fauser1, Luca Gianaroli2, Edgar Mocanu3

  • 1University Medical Center Utrecht and University of Utrecht, Utrecht, The Netherlands..

PubMed
Summary

Global family planning policies have successfully reduced population growth, leading to below-replacement fertility rates in many nations. This shift necessitates a greater focus on family-building strategies to address emerging societal challenges.

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Infertility in Males01:23

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Male infertility affects millions of couples worldwide, arising from various factors that impact different stages of the reproductive process. An endocrine imbalance resulting from conditions like hypogonadism, Klinefelter syndrome, or pituitary disorders can disrupt hormone levels and reduce sperm production. Testicular defects, such as tumors, cryptorchidism, atrophic testes, abnormal sperm morphology, and low sperm count or motility, may arise due to genetic factors, structural...
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Fertilization01:38

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During fertilization, an egg and sperm cell fuse to create a new diploid structure. In humans, the process occurs once the egg has been released from the ovary, and travels into the fallopian tubes. The process requires several key steps: 1) sperm present in the genital tract must locate the egg; 2) once there, sperm need to release enzymes to help them burrow through the protective zona pellucida of the egg; and 3) the membranes of a single sperm cell and egg must fuse, with the sperm...
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Infertility in Females01:28

Infertility in Females

Female infertility is defined as the inability to conceive after a year of regular, unprotected intercourse and affects about 10–15% of couples worldwide. The primary cause of female infertility is ovulatory disorders, which hinder the release of eggs. These disorders can be classified as hypothalamic amenorrhea, polycystic ovarian syndrome (PCOS), premature ovarian failure, and hyperprolactinemic anovulation disorders.
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Spermatogenesis01:41

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Crossing Over01:34

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The Ratio of X Chromosome to Autosomes02:45

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