Adenomyosis can vary widely in the type and severity of symptoms that it causes, ranging from being entirely asymptomatic 33% of the time to being a severe and debilitating condition in some cases. Women with adenomyosis typically first report symptoms when they are between 40 and 50, but symptoms can occur in younger women.

Symptoms and the estimated percent affected may include:

- Chronic pelvic pain (77%)

- Heavy menstrual bleeding (40-60%), which is more common with in women with deeper adenomyosis. Blood loss may be significant enough to cause anemia, with associated symptoms of fatigue, dizziness, and moodiness.

- Abnormal uterine bleeding

- Painful cramping menstruation (15-30%)

- Painful vaginal intercourse (7%)

- A 'bearing' down feeling

- Pressure on bladder

- Dragging sensation down thighs and legs

Clinical signs of adenomyosis may include:

- Uterine enlargement (30%), which in turn can lead to symptoms of pelvic fullness.

- Tender uterus

- Infertility or sub-fertility (11-12%) - In addition, adenomyosis is associated with an increased incidence of preterm labour and premature rupture of membranes.

Women with adenomyosis are also more likely to have other uterine conditions, including:

- Uterine fibroids (50%)

- Endometriosis (11%)

- Endometrial polyp (7%)

Adenomyosis is a gynecologic medical condition characterized by the abnormal presence of endometrial tissue (the inner lining of the uterus) within the myometrium (the thick, muscular layer of the uterus). In contrast, when endometrial tissue is present entirely outside the uterus, it represents a similar but distinct medical condition called endometriosis. The two conditions are found together in many cases, but often occur independently. Before being recognized as its own condition, adenomyosis used to be called "endometriosis interna". Additionally, the less-commonly used term "adenomyometritis" is a more specific name for the condition, specifying involvement of the uterus.

The condition is typically found in women between the ages of 35 and 50 but can also be present in younger women. Patients with adenomyosis often present with painful and/or profuse menses (dysmenorrhea & menorrhagia, respectively). Other possible symptoms are pain during sexual intercourse, chronic pelvic pain and irritation of the urinary bladder.

In adenomyosis, "basal" endometrium penetrates into hyperplastic myometrial fibers. Therefore, unlike functional layer, basal layer does not undergo typical cyclic changes with menstrual cycle.

Adenomyosis may involve the uterus focally, creating an adenomyoma. With diffuse involvement, the uterus becomes bulky and heavier.

The arcuate uterus is a form of a uterine anomaly or variation where the uterine cavity displays a concave contour towards the fundus. Normally the uterine cavity is straight or convex towards the fundus on anterior-posterior imaging, but in the arcuate uterus the myometrium of the fundus dips into the cavity and may form a small septation. The distinction between an arcuate uterus and a septate uterus is not standardized.

A unicornuate uterus represents a uterine malformation where the uterus is formed from one only of the paired Müllerian ducts while the other Müllerian duct does not develop or only in a rudimentary fashion. The sometimes called "hemi-uterus" has a single horn linked to the ipsilateral fallopian tube that faces its ovary.

The significance of endosalpingiosis is not settled; medical experts differ on whether the condition itself causes issues or whether it is an asymptomatic finding. Common symptoms include, pelvic pain, infertility, menstrual irregularities and dyspareunia. Further reports suggest chronic back pain as a common issue reported years before diagnosis. Experts are unclear as the condition itself is a rare finding and lack of knowledge presents itself as a challenge.

Like the uterine endometrium of Endometriosis, estrogen can cause salpingoitic tissues outside of the fallopian tubes to grow and potentially aggravate the surrounding areas. High levels cause the glandular tissues to proliferate and, especially important, they cause the number of and activity of ciliated epithelial cells (that would normally line the fallopian tubes) to increase.

Hematometra typically presents as cyclic, cramping pain in the midline of the pelvis or lower abdomen. Patients may also report urinary frequency and urinary retention. Premenopausal women with hematometra often experience abnormal vaginal bleeding, including dysmenorrhea (pain during menstruation) or amenorrhea (lack of menstruation), while postmenopausal women are more likely to be asymptomatic. Due to the accumulation of blood in the uterus, patients may develop low blood pressure or a vasovagal response. When palpated, the uterus will typically feel firm and enlarged.

In gynecology, endosalpingiosis is a condition in which fallopian tube-like epithelium is found outside the fallopian tube. It is unknown what causes this condition. It is generally accepted that the condition develops from transformation of coelomic tissue. It is often an incidental finding and is not usually associated with any pathology.

The following table distinguishes among some of the terms used for the position of the uterus:

A retroverted uterus should be distinguished from the following:

Additional terms include:

- "retrocessed uterus:" both the superior and inferior ends of the uterus are pushed posteriorly

- "severely anteflexed uterus:" the uterus is in the same position as "normal" and bends in the same direction (concave is anterior) but the bend is much more pronounced

- "vertical uterus:" the fundus (top of the uterus) is straight up.

In most cases, a retroverted uterus is genetic and is perfectly normal but there are other factors that can cause the uterus to be retroverted. Some cases are caused by pelvic surgery, pelvic adhesions, endometriosis, fibroids, pelvic inflammatory disease, or the labor of childbirth.

Women with the condition may be asymptomatic and unaware of having a uniconuate uterus; normal pregnancy may occur. In a review of the literature Reichman et al. analyzed the data on pregnancy outcome of 290 women with a unicornuate uterus. 175 women had conceived for a total of 468 pregnancies. They found that about 50% of patients delivered a live baby. The rates for ectopic pregnancy was 2.7%, for miscarriage 34%, and for preterm delivery 20%, while the intrauterine demise rate was 10%. Thus patients with a unicornuate uterus are at a higher risk for pregnancy loss and obstetrical complications.

A bicornuate uterus or bicornate uterus (from the Latin "cornū", meaning "horn"), commonly referred to as a "heart-shaped" uterus, is a uterus composed of two "horns" separated by a septum. In humans, a bicornuate uterus is a type of uterine malformation, but in some other mammalian species, including rodents and pigs, it is normal.

It is possible to diagnose a bicornuate uterus using gynecologic ultrasonography, specifically sonohysterography, and MRI. However, as there is no indication to do such procedures on asymptomatic women, the presence of a bicornuate uterus may not be detected until pregnancy or delivery.

In a C-section (usually done due to malpresentation), the irregular shape of the uterus will be apparent.

Other less reliable diagnostic imaging methods include hysterosalpingography and hysteroscopy; these procedures are typically done during the course of an infertility investigation.

A uterine septum is a form of a congenital malformation where the uterine cavity is partitioned by a longitudinal septum; the outside of the uterus has a normal typical shape. The wedge-like partition may involve only the superior part of the cavity resulting in an "incomplete septum" or a "subseptate uterus", or less frequently the total length of the cavity ("complete septum") and the cervix resulting in a double cervix. The septation may also continue caudally into the vagina resulting in a "double vagina".

Molar pregnancies usually present with painless vaginal bleeding in the fourth to fifth month of pregnancy. The uterus may be larger than expected, or the ovaries may be enlarged. There may also be more vomiting than would be expected (hyperemesis). Sometimes there is an increase in blood pressure along with protein in the urine. Blood tests will show very high levels of human chorionic gonadotropin (hCG).

Hematometra or hemometra is a medical condition involving collection or retention of blood in the uterus. It is most commonly caused by an imperforate hymen or a transverse vaginal septum.

Molar pregnancy is an abnormal form of pregnancy in which a non-viable fertilized egg implants in the uterus and will fail to come to term.

A molar pregnancy is a gestational trophoblastic disease which grows into a mass in the uterus that has swollen chorionic villi. These villi grow in clusters that resemble grapes. A molar pregnancy can develop when a fertilized egg does not contain an original maternal nucleus. The products of conception may or may not contain fetal tissue. It is characterized by the presence of a hydatidiform mole (or hydatid mole, mola hydatidosa). Molar pregnancies are categorized as partial moles or complete moles, with the word "mole" being used to denote simply a clump of growing tissue, or a "growth".

A complete mole is caused by a single sperm (incidence is about 90%) or two (incidence is about 10%) sperms combining with an egg which has lost its DNA (in the first case the sperm then reduplicates forming a "complete" 46 chromosome set). The genotype is typically 46,XX (diploid) due to subsequent mitosis of the fertilizing sperm, but can also be 46,XY (diploid). 46,YY (diploid) is not observed. In contrast, a partial mole occurs when a haploid egg is fertilized by two sperm or by one sperm which reduplicates itself yielding the genotypes of 69,XXY (triploid) or 92,XXXY (tetraploid). Complete hydatidiform moles have 2 - 4% risk of developing into choriocarcinoma in Western countries and 10 - 15% in Eastern countries and overall, also a 15% chance of becoming an invasive mole. Incomplete moles can become invasive (<5% risk) but are not associated with choriocarcinoma. Complete hydatidiform moles account for 50% of all cases of choriocarcinoma.

The American Fertility Society (now American Society of Reproductive Medicine) Classification distinguishes:

- Class I: Müllerian agenesis (absent uterus).

- Uterus is not present, vagina only rudimentary or absent. The condition is also called Mayer-Rokitansky-Kuster-Hauser syndrome. The patient with MRKH syndrome will have primary amenorrhea.

- Class II: Unicornuate uterus (a one-sided uterus).

- Only one side of the Müllerian duct forms. The uterus has a typical "banana shape" on imaging systems.

- Class III: Uterus didelphys, also uterus didelphis (double uterus).

- Both Müllerian ducts develop but fail to fuse, thus the patient has a "double uterus". This may be a condition with a double cervix and a vaginal partition (v.i.), or the lower Müllerian system fused into its unpaired condition. See Triplet-birth with Uterus didelphys for a case of a woman having spontaneous birth in both wombs with twins.

- Class IV: Bicornuate uterus (uterus with two horns).

- Only the upper part of that part of the Müllerian system that forms the uterus fails to fuse, thus the caudal part of the uterus is normal, the cranial part is bifurcated. The uterus is "heart-shaped".

- Class V: Septated uterus (uterine septum or partition).

- The two Müllerian ducts have fused, but the partition between them is still present, splitting the system into two parts. With a complete septum the vagina, cervix and the uterus can be partitioned. Usually the septum affects only the cranial part of the uterus. A uterine septum is the most common uterine malformation and a cause for miscarriages. It is diagnosed by medical image techniques, i.e. ultrasound or an MRI. MRI is considered the preferred modality due to its multiplanar capabilities as well as its ability to evaluate the uterine contour, junctional zone, and other pelvic anatomy. A hysterosalpingogram is not considered as useful due to the inability of the technique to evaluate the exterior contour of the uterus and distinguish between a bicornuate and septate uterus.

A uterine septum can be corrected by hysteroscopic surgery.

- Class VI: DES uterus.

- The uterine cavity has a "T-shape" as a result of fetal exposure to diethylstilbestrol.

An additional variation is the arcuate uterus where there is a concave dimple in the uterine fundus within the cavity.

A rudimentary uterus is a uterine remnant not connected to cervix and vagina and may be found on the other side of an unicornuate uterus.

Patients with uterine abnormalities may have associated renal abnormalities including unilateral renal agenesis.

They often cause no symptoms. Where they occur, symptoms include irregular menstrual bleeding, bleeding between menstrual periods, excessively heavy menstrual bleeding (menorrhagia), and vaginal bleeding after menopause. Bleeding from the blood vessels of the polyp contributes to an increase of blood loss during menstruation and blood "spotting" between menstrual periods, or after menopause. If the polyp protrudes through the cervix into the vagina, pain (dysmenorrhea) may result.

Endometrioma is the presences of endometrial tissue in and sometimes on the ovary. More broadly, endometriosis is the presence of endometrial tissue located outside the uterus. The presence of endometriosis can result in the formation of scar tissue, adhesions and an inflammatory reaction. It is a benign growth. An endometrioma is most often found in the ovary. It can also develop in the cul-de-sac (space be hind the uterus), the surface of the uterus, and between the vagina and rectum.

Some women with uterine fibroids do not have symptoms. Abdominal pain, anemia and increased bleeding can indicate the presence of fibroids. There may also be pain during intercourse, depending on the location of the fibroid. During pregnancy, they may also be the cause of miscarriage, bleeding, premature labor, or interference with the position of the fetus. A uterine fibroid can cause rectal pressure. The abdomen can grow larger mimicking the appearance of pregnancy. Some large fibroids can extend out through the cervix and vagina.

While fibroids are common, they are not a typical cause for infertility, accounting for about 3% of reasons why a woman may not be able to have a child. The majority of women with uterine fibroids will have normal pregnancy outcomes. In cases of intercurrent uterine fibroids in infertility, a fibroid is typically located in a submucosal position and it is thought that this location may interfere with the function of the lining and the ability of the embryo to implant.

The most common presentation is vaginal bleeding. Other presentations include pelvic mass and uterine polyp. Generally, the clinical findings are non-specific.

As the vagina is largely derived from the Müllerian ducts, lack of fusion of the two ducts can lead to the formation of a vaginal duplication and lack of absorption of the wall between the two ducts will leave a residual septum, leading to a "double vagina". This condition may be associated with a uterus didelphys or a uterine septum. Since the condition is internal and usually asymptomatic, a person may not be aware of having a "double vagina." If necessary, the partition can be surgically corrected, however, there is no valid medical reason for such a procedure.

Uterus didelphys (sometimes also "uterus didelphis") represents a uterine malformation where the uterus is present as a paired organ when the embryogenetic fusion of the Müllerian ducts fails to occur. As a result, there is a double uterus with two separate cervices, and rarely a double vagina as well. Each uterus has a single horn linked to the ipsilateral fallopian tube that faces its ovary.

In non human species ("e.g." nematodes), a didelphic genital tract may be normal rather than a malformation. Such species are described as didelphic, as opposed to monodelphic, with a single tract.

A specific association of uterus didelphys (double uterus), unilateral hematocolpos (inadequate draining of menstrual blood) and ipsilateral renal agenesis (having only one kidney) has been described.

Fibroids that lead to heavy vaginal bleeding lead to anemia and iron deficiency. Due to pressure effects gastrointestinal problems such as constipation and bloatedness are possible. Compression of the ureter may lead to hydronephrosis. Fibroids may also present alongside endometriosis, which itself may cause infertility. Adenomyosis may be mistaken for or coexist with fibroids.

In very rare cases, malignant (cancerous) growths, leiomyosarcoma, of the myometrium can develop. In extremely rare cases uterine fibroids may present as part or early symptom of the hereditary leiomyomatosis and renal cell cancer syndrome.