The great majority of vaginal discharges are normal or physiological and include blood or menses ( from the uterus ), the most common, and clear fluid either as a result of sexual arousal or secretions from the cervix.

* The majority of species are ovoviviparous: the medium-sized eggs, encased only by a double membrane, remain in the uterus.

Fraternal or dizygotic ( DZ ) twins ( also referred to as " non-identical twins ", " dissimilar twins ", " biovular twins ", and, in cases of females, sororal twins ) usually occur when two fertilized eggs are implanted in the uterus wall at the same time.

IAG – ice dildo – ice play – ICSH – ICSI – Ideal Marriage: Its Physiology and Technique – idealization of romantic love – identical twins – idiographic – idiopathic – idiopathic adolescent gynecomastia – illegal sex – illegitimacy – illegitimate child – image club – Imaginative Sex – immissio penis – immunocontraception – imperforate hymen – impersonator – Implanon – impotence – impotentia coeundi – impotentia procreandi – impregnation – imprinting – imsak ( sexual technique ) – in flagrante – in flagrante delicto – in vitro fertilisation – in vitro fertilization – incest – incontinence – incubus – indecent exposure – Indian marriage customs – indolamine – infancy – infantilism – infantophilia – infatuation – infertility – infibulation – infidelity – inflatable doll – inflatable fetishism – inflation fetishism – informed consent – infundibulum of uterine tube – inhibited orgasm – inhibited sexual desire – Inis Beag – innate bisexuality – insect fetish – insemination – insertion fantasy – Institut für Sexualwissenschaft – Institute for Advanced Study of Human Sexuality – insufflation – interaxillary intercourse – intercourse – intercrural intercourse – interfemoral intercourse – intergenerational – interlabial sulci – intermammary intercourse – intermarriage ( disambiguation ) – intermediate part of male urethra – internal orifice of the uterus – internal pudendal artery – internal spermatic fascia – internal urethral orifice – internalized homophobia – International Academy of Sex Research – International Encyclopedia of Sexuality – Internet pornography – interoceptive – interracial pornography – interreligious marriage – interrogation scene – intersex – Intersex Society of North America – intersexuality – interstitial cell stimulating hormone – intimacy – intimacy-avoidancy – intimate examination – intimate relationship – intracavernosal injection – intracytoplasmic sperm injection – intrauterine device – introitus – intromission – Inuit marriage customs – Inuit wedding – inunction – invert – inviolacy – involuntary celibacy – involuntary sterilization – irrumatio – irrumation – Isabella piercing – ischiocavernosus muscle – Islamic marriage customs – Islamic view of marriage – Islamic views of homosexuality – isthmus of uterine tube – IUD – IUS – IVF –

Ovulation is not affected, and the IUD is not an abortifacient .< sup > 58 – 60 </ sup > It is currently believed that the mechanism of action for IUDs is the production of an intrauterine environment that is spermicidal. Nonmedicated IUDs depend for contraception on the general reaction of the uterus to a foreign body.

; Week 1 – 3: 5 – 7 days after fertilization, the blastocyst attaches to the wall of the uterus ( endometrium ).

* Amniotic fluid embolism – embolism of amniotic fluid, foetal cells, hair, or other debris that enters the mother's bloodstream via the placental bed of the uterus and triggers an allergic reaction.

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These uNK cells are the most abundant leukocytes present in the uterus in early pregnancy, representing approximately 70 % of leukocytes here, however where they originate from remains controversial.

In monotremes, mammals which lay eggs, namely the platypus and the echidnas, either the term uterus or oviduct is used to describe the same organ, but the egg does not develop a placenta within the mother and thus does not receive further nourishment after formation and fertilization.

The embryos found in the uterus of a single female do not necessarily have to be of the same age ; it is quite possible for there to be offspring at different stages of development and descended from different males.

However, anatomically, the uterus is in the same position as the prostate gland.

* Sideways: also keeps pressure off of her abdomen while supporting her uterus at the same time.

# there is no more vitelline mass, but the embryo is possessed of long external gills, which serve for an exchange of nutritive fluid through the maternal uterus, these gills functioning in the same way as the chorionic villi of the mammalian egg.

Note: not the same uterus as in ultrasound or hysteroscopic view ; this uterus appears to be T-shaped.

The Endometrial implants that grow into the wall of the uterus bleed during menstruation, ( the same as endometrial tissue bleeds ) is discharged vaginally as menstrual bleeding.

In North America, of the 17 species of Vernonia ( e. g. V. altissima, V. fasciculata, V. flaccidifolia ) all have the same effective properties as a blood purifier and uterus toner, containing sesquiterpene lactone, which helps also to prevent atherosclerosis.

Several days later, chorionic villi in the forming placenta anchor the implantation site to the uterus.

The fertilized ovum becomes an embryo, attaches to a wall of the uterus, creates a placenta, and develops into a fetus ( gestates ) until childbirth.

The supply of food takes place either via a secretion from the mother directly into the uterus or via a genuine tissue connection between the epithelium of the uterus and the developing embryo, known as a placenta.

Successful pregnancies have been reported from ruptured tubal pregnancy continuing by the placenta implanting on abdominal organs or on the outside of the uterus.

Image: Catfetus1. jpg | Opened uterus with cat fetus in midgestation: 1 umbilicus, 2 amnion, 3 allantois, 4 Yolk sac, 5 developing marginal hematoma, 6 maternal part of placenta ( endometrium )

Oxygenated blood is delivered to the fetus via the umbilical vein from the placenta, which is anchored to the wall of the mother's uterus.

Although the fetus was in a similar state of decomposition, the umbilical cord was intact and still attached to the placenta inside the uterus.

The umbilical cord was still intact, and connected the fetus to the placenta via the ruptured wall of the uterus.

* Type I or low lying: The placenta encroaches the lower segment of the uterus but does not infringe on the cervical os.

Trophoblasts are specialised cells of the placenta that play an important role in embryo implantation and interaction with the decidualised maternal uterus.

Extravillous trophoblast grow out from the placenta and penetrate into the decidualised uterus.

This process is essential not only for physically attaching the placenta to the mother, but also for altering the vasculature in the uterus to allow it to provide an adequate blood supply to the growing fetus as pregnancy progresses.

The uterus contains two conceptuses: one with an abnormal placenta and no viable fetus ( the mole ), and one with a normal placenta and a viable fetus.

The placenta contains high levels of prostaglandin which stimulates involution ( an inward curvature or penetration, or, a shrinking or return to a former size ) of the uterus, in effect cleaning the uterus out.

Image: Catfetus1. jpg | Opened uterus with cat fetus in midgestation: 1 umbilicus, 2 amnion, 3 allantois, 4 Yolk sac, 5 developing marginal hematoma, 6 maternal part of placenta ( endometrium )

* If a large amount of the placenta separates from the uterus, the baby will probably be in distress until delivery and may die in utero, thus resulting in a stillbirth.

This can push the placenta away from the uterus and cause further bleeding.

The scope of an artificial uterus ( or " artificial uterus system " to emphasis a broader scope ) may also include the interface serving the function otherwise provided by the placenta, an amniotic tank functioning as the amniotic sac, as well as an umbilical cord.

Of those who have an asymptomatic infection that is not detected by their doctor, approximately half will develop pelvic inflammatory disease ( PID ), a generic term for infection of the uterus, fallopian tubes, and / or ovaries.

The initial single cell combination is already dividing and by the time of entry into the uterus, the egg might have already reached the blastocyst stage.

Humans and other higher primates such as chimpanzees, along with horses, usually have a single completely fused uterus, although in some individuals the uteri may not have completely fused.

Most animals that lay eggs, such as birds and reptiles, including most ovoviviparous species, have an oviduct instead of a uterus.

Occasionally, some individual females ( including humans ) may have a bicornuate uterus, a uterine malformation where the two parts of the uterus fail to fuse completely during fetal development.

Strassman correlates species that have overt menstruation to those that have a large uterus relative to the adult female body size.

Women who have their uterus removed but retain their ovaries do not immediately go into menopause, even though their periods cease.

As an illustration of the central role that the ovaries play, it is worth pointing out that when for medical reasons the uterus has to be surgically removed ( hysterectomy ) in a younger woman, her periods will of course cease permanently, and the woman will be incapable of pregnancy, but as long as at least one of her ovaries is still functioning, the woman will not have reached menopause.

In women who have a uterus, perimenopause describes the years before and after the final period ( although it is only possible to determine in retrospect which episode of flow was indeed the final period ).

The term postmenopause is applied to women who have not experienced a menstrual bleed for a minimum of 12 months, assuming that they do still have a uterus, and are not pregnant or lactating.

In women who have no uterus, and therefore have no periods, post-menopause can be determined by a blood test which can reveal the very high levels of Follicle Stimulating Hormone ( FSH ) that are typical of post-menopausal women.

In those women who have no uterus ( usually due to a previous hysterectomy ), estrogen alone is a suitable hormone therapy and is in fact preferable to continuing to use progesterone when its function as a moderating influence on growth of the endometrium ( uterine lining ) is no longer required.

Women who still have a uterus need to take progesterone in addition to estrogen to protect against the development of endometrial hyperplasia and endometrial carcinoma.

A 46, XY female thus does not have ovaries or a uterus, and can neither contribute an egg towards conception nor gestate a child.

By the time a correct diagnosis has been made, endometrium and other fluids have filled the uterus and fallopian tubes with results similar to retrograde menstruation resulting in endometriosis.

Hermaphrodites have two ovaries, oviducts, spermatheca, and a single uterus.

Unfolded wire clothes hangers, because of their use in performing illegal or self-induced abortions ( by inserting one in the uterus ), have been used for pro-choice protest.