Human reproduction is an inefficient process. A significant proportion of our inefficiency can be attributed to embryonic aneuploidy, i. The embryo having an abnormal chromosome number. Most of us have 46 chromosomes. Most of our embryos do not.
Why do Chromosomally Normal Embryos Not Implant in the Uterus?
Why Can’t I Get Pregnant? | Johns Hopkins Medicine
Jump to content. Most women are able to become pregnant from puberty , when their menstrual cycles begin, until menopause , when their cycles stop. A pregnancy starts with fertilization, when a woman's egg joins with a man's sperm. Fertilization usually takes place in a fallopian tube that links an ovary to the uterus. If the fertilized egg successfully travels down the fallopian tube and implants in the uterus, an embryo starts growing. All the eggs for a woman's lifetime are stored in her ovaries. Women do not keep producing eggs.
Fate of a Fertilized Egg: Why Some Embryos Don't Implant
Learn more. Chantel Cross, M. You may start to wonder — is this a medical problem or do I simply need to be more patient? One in 8 couples struggles to conceive. Infertility is defined as the inability to become pregnant after one year of unprotected sex for women under 35 and six months for women 35 and older.
Try out PMC Labs and tell us what you think. Learn More. The success rate of reproductive treatment methods depends on many different factors. The most important and discussed ones in the literature are maternal age, the causes of infertility, the ovarian response to stimulation, the influence of the male factor and sperm quality, embryo quality and the various uterine pathologies. It can be speculated that in these couples, insufficiency of the endometrium might be a possible reason for implantation failure.