Diets high in fruits and vegetables tend to lower the risk of developing fibroids. Fruits, especially citrus, have a greater protective benefit than vegetables. Normal dietary levels of vitamin D is shown to reduce the risk of developing fibroids. No protective benefit has been found with the consumption of folate, whole grains, soy products, or fiber. No association between the consumption of fat, eggs, dairy products has been shown to increase the risk of fibroids.

Some risk factors associated with the development of uterine fibroids are modifiable.

Fibroids are more common in obese women. Fibroids are dependent on estrogen and progesterone to grow and therefore relevant only during the reproductive years.

The cause is not entirely clear. Risk factors include having a family history of the condition.

Some factors associated with endometriosis include:

- not having had yet given birth

- prolonged exposure to estrogen - for example, in late menopause or early menarche

- obstruction of menstrual outflow - for example, in Müllerian anomalies

Several studies have investigated the potential link between exposure to dioxins and endometriosis, but the evidence is equivocal and potential mechanisms are poorly understood. A 2004 review of studies of dioxin and endometriosis concluded that "the human data supporting the dioxin-endometriosis association are scanty and conflicting", and a 2009 follow-up review also found that there was "insufficient evidence" in support of a link between dioxin exposure and women developing endometriosis. A 2008 review concluded that more work was needed, stating that "although preliminary work suggests a potential involvement of exposure to dioxins in the pathogenesis of endometriosis, much work remains to clearly define cause and effect and to understand the potential mechanism of toxicity".

Adenomyosis itself can cause infertility issues, however, fertility can be improved if the adenomyosis has resolved following hormone therapies like levonorgestrel therapy. The discontinuation of medication or removal of IUD can be timed to be coordinated with fertility treatments. There has also been one report of a successful pregnancy and healthy birth following high-frequency ultrasound ablation of adenomyosis.

Preterm labour and premature rupture of membranes both occur more frequently in women with adenomyosis.

In sub-fertile women who received in-vitro fertilization (IVF), women with adenomyosis were less likely to become pregnant and subsequently more likely to experience a miscarriage. Given this, it is encouraged to screen women for adenomyosis by TVUS or MRI before starting assisted reproduction treatments (ART).

Adenomyosis is a benign but often progressing condition. It is advocated that adenomyosis poses no increased risk for cancer development. However, both entities could coexist and the endometrial tissue within the myometrium could harbor endometrioid adenocarcinoma, with potentially deep myometrial invasion. As the condition is estrogen-dependent, menopause presents a natural cure. Ultrasound features of adenomyosis will still be present after menopause. People with adenomyosis are also more likely to have uterine fibroids or endometriosis.

Vaginal bleeding occurs during 15-25% of first trimester pregnancies. Of these, half go on to miscarry and half bring the fetus to term. There are a number of causes including rupture of a small vein on the outer rim of the placenta. It can also herald a miscarriage or ectopic pregnancy, which is why urgent ultrasound is required to separate the two causes. Bleeding in early pregnancy may be a sign of a threatened or incomplete miscarriage.

In the second or third trimester a placenta previa (a placenta partially or completely overlying the cervix) may bleed quite severely. Placental abruption is often associated with uterine bleeding as well as uterine pain.

Endometrial atrophy, uterine fibroids, and endometrial cancer are common causes of postmenopausal vaginal bleeding.

Dysmenorrhea can be classified as either primary or secondary based on the absence or presence of an underlying cause. Secondary dysmenorrhea is dysmenorrhea which is associated with an existing condition.

The most common cause of secondary dysmenorrhea is endometriosis, which can be visually confirmed by laparoscopy in approximately 70% of adolescents with dysmenorrhea.

Other causes of secondary dysmenorrhea include leiomyoma, adenomyosis, ovarian cysts, and pelvic congestion.

Unequal leg length might hypothetically be one of the contributors, as it may contribute to a tilted pelvis, which may cause lower back pain, which in turn may be mistaken for menstrual pain, as women with lower back pain experience increased pain during their periods.

Other skeletal abnormalities, such as scoliosis (sometimes caused by spina bifida) might be possible contributors as well.

Uterine hyperplasia, or enlarged uterus, is a medical symptom in which the volume and size of the uterus in a female is abnormally high. It can be a symptom of medical conditions such as adenomyosis, uterine fibroids, ovarian cysts, and endometrial cancer.

During a woman's menstrual cycle, the endometrium thickens in preparation for potential pregnancy. After ovulation, if the ovum is not fertilized and there is no pregnancy, the built-up uterine tissue is not needed and thus shed.

Molecular compounds called prostaglandins are released during menstruation, due to the destruction of the endometrial cells, and the resultant release of their contents. Release of prostaglandins and other inflammatory mediators in the uterus cause the uterus to contract. These substances are thought to be a major factor in primary dysmenorrhea. When the uterine muscles contract, they constrict the blood supply to the tissue of the endometrium, which, in turn, breaks down and dies. These uterine contractions continue as they squeeze the old, dead endometrial tissue through the cervix and out of the body through the vagina. These contractions, and the resulting temporary oxygen deprivation to nearby tissues, are responsible for the pain or "cramps" experienced during menstruation.

Compared with other women, women with primary dysmenorrhea have increased activity of the uterine muscle with increased contractility and increased frequency of contractions.

In one research study using MRI, visible features of the uterus were compared in dysmenorrheic and eumenorrheic (normal) participants. The study concluded that in dysmenorrheic patients, visible features on cycle days 1-3 correlated with the degree of pain, and differed significantly from the control group.

A boggy uterus is a finding upon physical examination where the uterus is more flaccid than would be expected.

It can be associated with uterine atony.

It may also be associated with adenomyosis.

Adenomyoma is a tumor ("-oma") including components derived from glands ("adeno-") and muscle ("-my-"). It is a type of complex and mixed tumor.

In obstetrics and gynecology contexts, it is a form of adenomyosis that forms a mass or growth around the tissue of the inner uterus.

Most cases of adenomyosis are non-symptomatic. However, it may present with dysmenorrhea and pelvic pain. In the case of juvenile cystic adenomyoma, laparoscopic enucleation results in a statistically and clinically significant reduction in dysmenorrhea, ease in any chronic pelvic pain, and low risk of recurrence.

An estrogen-dependent condition, disease, disorder, or syndrome, is a medical condition that is, in part or full, dependent on, or is sensitive to, the presence of estrogenic activity in the body.

Known estrogen-dependent conditions include mastodynia (breast pain/tenderness), breast fibroids, mammoplasia (breast enlargement), macromastia (breast hypertrophy), gynecomastia, breast cancer, precocious puberty in girls, melasma, menorrhagia, endometriosis, endometrial hyperplasia, adenomyosis, uterine fibroids, uterine cancers (e.g., endometrial cancer), ovarian cancer, and hyperestrogenism in males such as in certain conditions like cirrhosis and Klinefelter's syndrome.

Such conditions may be treated with drugs with antiestrogen actions, including selective estrogen receptor modulators (SERMs) such as tamoxifen and clomifene, estrogen receptor antagonists such as fulvestrant, aromatase inhibitors such as anastrozole and exemestane, gonadotropin-releasing hormone (GnRH) analogues such as leuprolide and cetrorelix, and/or other antigonadotropins such as danazol, gestrinone, megestrol acetate, and medroxyprogesterone acetate.