where does implantation of the fertilized ovum usually occur
wall of the uterus
title: Implantation (human embryo) text: Implantation (human embryo) In humans, implantation is the stage of pregnancy at which the embryo adheres to the wall of the uterus. At this stage of prenatal development, the conceptus is called a blastocyst. It is by this adhesion that the embryo receives oxygen and nutrients from the mother to be able to grow. In humans, implantation of a fertilized ovum is most likely to occur around 9 days after ovulation, however this can range between 6 and 12 days. The reception-ready phase of the endometrium of the uterus is usually termed the "implantation window" and lasts about 4 days. title: Human reproductive system text: Human reproductive system The human reproductive system usually involves internal fertilization by sexual intercourse. In this process, the male inserts his penis into the female's vagina and ejaculates semen, which contains sperm. A small proportion of the sperm pass through the cervix into the uterus, and then into the Fallopian tubes for fertilization of the ovum. Only one sperm is required to fertilize the ovum. Upon successful fertilization, the fertilized ovum, or zygote, travels out of the Fallopian tube and into the uterus, where it implants in the uterine wall. This marks the beginning of gestation, better known as pregnancy, title: Uterus text: a double uterus, didelphic uterus, bicornate uterus and others. The reproductive function of the uterus is to accept a fertilized ovum which passes through the utero-tubal junction from the fallopian tube (uterine tube). The fertilized ovum divides to become a blastocyst, which implants into the endometrium, and derives nourishment from blood vessels which develop exclusively for this purpose. The fertilized ovum becomes an embryo, attaches to a wall of the uterus, creates a placenta, and develops into a fetus (gestates) until childbirth. Due to anatomical barriers such as the pelvis, the uterus is pushed partially into the abdomen due to title: Implantation (human embryo) text: The implantation window occurs around 6 days after the peak in luteinizing hormone levels. With some disparity between sources, it has been stated to occur from 7 days after ovulation until 9 days after ovulation, or days 6-10 postovulation. On average, it occurs during the 20th to the 23rd day after the last menstrual period. The implantation window is characterized by changes to the endometrium cells, which aid in the absorption of the uterine fluid. These changes are collectively known as the plasma membrane transformation and bring the blastocyst nearer to the endometrium and immobilize it. During this stage the title: Mammalian reproduction text: produce the female's ova. All of these parts are always internal. The vagina is attached to the uterus through the cervix, while the uterus is attached to the ovaries via the Fallopian tubes. At certain intervals, the ovaries release an ovum, which passes through the fallopian tube into the uterus. If, in this transit, it meets with sperm, the egg selects sperm with which to merge; this is termed fertilization. The fertilization usually occurs in the oviducts, but can happen in the uterus itself. The zygote then implants itself in the wall of the uterus, where it begins the processes