Cases of GTD can be diagnosed through routine tests given during pregnancy, such as blood tests and ultrasound, or through tests done after miscarriage or abortion. Vaginal bleeding, enlarged uterus, pelvic pain or discomfort, and vomiting too much (hyperemesis) are the most common symptoms of GTD. But GTD also leads to elevated serum hCG (human chorionic gonadotropin hormone). Since pregnancy is by far the most common cause of elevated serum hCG, clinicians generally first suspect a pregnancy with a complication. However, in GTD, the beta subunit of hCG (beta hCG) is also always elevated. Therefore, if GTD is clinically suspected, serum beta hCG is also measured.

The initial clinical diagnosis of GTD should be confirmed histologically, which can be done after the evacuation of pregnancy (see «Treatment» below) in women with hydatidiform mole. However, malignant GTD is highly vascular. If malignant GTD is suspected clinically, biopsy is contraindicated, because biopsy may cause life-threatening haemorrhage.

Women with persistent abnormal vaginal bleeding after any pregnancy, and women developing acute respiratory or neurological symptoms after any pregnancy, should also undergo hCG testing, because these may be signs of a hitherto undiagnosed GTD.

Women with a hydatidiform mole have an excellent prognosis. Women with a malignant form of GTD usually have a very good prognosis.

Choriocarcinoma, for example, is an uncommon, yet almost always curable cancer. Although choriocarcinoma is a highly malignant tumour and a life-threatening disease, it is very sensitive to chemotherapy. Virtually all women with non-metastatic disease are cured and retain their fertility; the prognosis is also very good for those with metastatic (spreading) cancer, in the early stages, but fertility may be lost. Hysterectomy (surgical removal of the uterus) can also be offered to patients > 40 years of age or those for whom sterilisation is not an obstacle. Only a few women with GTD have a poor prognosis, e.g. some forms of stage IV GTN. The FIGO staging system is used. The risk can be estimated by scoring systems such as the "Modified WHO Prognostic Scoring System", wherein scores between 1 and 4 from various parameters are summed together:

In this scoring system, women with a score of 7 or greater are considered at high risk.

It is very important for malignant forms of GTD to be discovered in time. In Western countries, women with molar pregnancies are followed carefully; for instance, in the UK, all women who have had a molar pregnancy are registered at the National Trophoblastic Screening Centre. There are efforts in this direction in the developing countries too, and there have been improvements in these countries in the early detection of choriocarcinoma, thereby significantly reducing the mortality rate also in developing countries.

The diagnosis is strongly suggested by ultrasound (sonogram), but definitive diagnosis requires histopathological examination. On ultrasound, the mole resembles a bunch of grapes ("cluster of grapes" or "honeycombed uterus" or "snow-storm"). There is increased trophoblast proliferation and enlarging of the chorionic villi. Angiogenesis in the trophoblasts is impaired as well.

Sometimes symptoms of hyperthyroidism are seen, due to the extremely high levels of hCG, which can mimic the normal Thyroid-stimulating hormone (TSH).

Hydatidiform moles should be treated by evacuating the uterus by uterine suction or by surgical curettage as soon as possible after diagnosis, in order to avoid the risks of choriocarcinoma. Patients are followed up until their serum human chorionic gonadotrophin (hCG) level has fallen to an undetectable level. Invasive or metastatic moles (cancer) may require chemotherapy and often respond well to methotrexate. As they contain paternal antigens, the response to treatment is nearly 100%. Patients are advised not to conceive for half a year after hCG levels have normalized. The chances of having another molar pregnancy are approximately 1%.

Management is more complicated when the mole occurs together with one or more normal fetuses.

Most women with a PUL are followed up with serum hCG measurements and repeat TVS examinations until a final diagnosis is confirmed. Low-risk cases of PUL that appear to be failing pregnancies may be followed up with a urinary pregnancy test after 2 weeks and get subsequent telephone advice. Low-risk cases of PUL that are likely intrauterine pregnancies may have another TVS in 2 weeks to access viability. High-risk cases of PUL require further assessment, either with a TVS within 48 h or additional hCG measurement.

A laparoscopy or laparotomy can also be performed to visually confirm an ectopic pregnancy. This is generally reserved for women presenting with signs of an acute abdomen and/or hypovolemic shock. Often if a tubal abortion or tubal rupture has occurred, it is difficult to find the pregnancy tissue. A laparoscopy in very early ectopic pregnancy rarely shows a normal looking fallopian tube.

Culdocentesis, in which fluid is retrieved from the space separating the vagina and rectum, is a less commonly performed test that may be used to look for internal bleeding. In this test, a needle is inserted into the space at the very top of the vagina, behind the uterus and in front of the rectum. Any blood or fluid found may have been derived from a ruptured ectopic pregnancy.

Progesterone levels of less than 20 nmol/l have a high predictive value for failing pregnancies, whilst levels over 25 nmol/l are likely to predict viable pregnancies, and levels over 60 nmol/l are strongly so. This may help in identifying failing PULs that are at low risk and thereby needing less follow-up. Inhibin A may also be useful for predicting spontaneous resolution of PUL, but is not as good as progesterone for this purpose.

In addition, there are various mathematical models, such as logistic regression models and Bayesian networks, for the prediction of PUL outcome based on multiple parameters. Mathematical models also aim to identify PULs that are "low risk", that is, failing PULs and IUPs.

Dilation and curettage is sometimes used to diagnose pregnancy location with the aim of differentiating between an EP and a non-viable IUP in situations where a viable IUP can be ruled out. Specific indications for this procedure include either of the following:

- no visible IUP on transvaginal ultrasonography with a serum hCG of more than 2000 IU/ml

- an abnormal rise in hCG level. A rise of 35% over 48 hours is proposed as the minimal rise consistent with a viable intrauterine pregnancy.

- an abnormal fall in hCG level, such as defined as one of less than 20% in 2 days

The diagnosis is made in asymptomatic pregnant women by obstetric ultrasonography. On pelvic examination a unilateral adnexal mass may be found. Typical symptoms are abdominal pain and, to a lesser degree, vaginal bleeding during pregnancy. Patients may present with hypovolemia or be in circulatory shock because of internal bleeding.

Ideally, ultrasound will show the location of the gestational sac in the ovary, while the uterine cavity is "empty", and if there is internal bleeding, it can be identified. Because of the proximity of the tube, the sonographic distinction between a tubal and an ovarian pregnancy may be difficult. Serial hCG levels generally show not the normal progressive rise.

In a series of 12 patients the mean gestation age was 45 days.

Histologically, the diagnosis has been made by Spiegelberg criteria on the surgical specimen of the removed ovary and tube. However, the tube and ovary are not usually removed as sonography allows for earlier diagnosis and surgeons strive to preserve the ovary. Prior to the introduction of Spiegelberg's criteria in 1878, the existence of ovarian pregnancy was in doubt; his criteria helped to identify the ovarian pregnancy from other ectopics:

- The gestational sac is located in the region of the ovary.

- The gestational sac is attached to the uterus by the ovarian ligament.

- Ovarian tissue is histologically proven in the wall of the gestational sac.

- The oviduct on the affected side is intact (this criterion, however, holds not true for a longer ongoing ovarian pregnancy).

An ovarian pregnancy can be mistaken for a tubal pregnancy or a hemorrhagic ovarian cyst or corpus luteum prior to surgery. Sometimes, only the presence of trophoblastic tissue during the histologic examination of material of a bleeding ovarian cyst shows that an ovarian pregnancy was the cause of the bleeding.

The exact incidence of maternal mortality related to placenta accreta and its complications is unknown, but has been reported to be as high as 6-7% in case series and surveys.

Ovarian pregnancies are dangerous and prone to internal bleeding. Thus, when suspected, intervention is called for.

Traditionally, an explorative laparotomy was performed, and once the ovarian pregnancy was identified, an oophorectomy or salpingo-oophorectomy was performed, including the removal of the pregnancy. Today, the surgery can often be performed via laparoscopy. The extent of surgery varies according to the amount of tissue destruction that has

occurred. Patients with an ovarian pregnancy have a good prognosis for future fertility and therefore conservative surgical management is advocated. Further, in attempts to preserve ovarian tissue, surgery may involve just the removal of the pregnancy with only a part of the ovary. This can be accomplished by an ovarian wedge resection.

Ovarian pregnancies have been successfully treated with methotrexate since it was introduced in the management of ectopic pregnancy in 1988.

An ovarian pregnancy can develop together with a normal intrauterine pregnancy; such a heterotopic pregnancy will call for expert management as not to endanger the intrauterine pregnancy.

Placental site trophoblastic tumor is a form of gestational trophoblastic disease, which is thought to arise from intermediate trophoblast.

It may secrete human placental lactogen (human chorionic somatomammotropin), and result in a false-positive pregnancy test.

Placental site trophoblastic tumor is a monophasic neoplasm of the implantation site intermediate trophoblast, and usually a benign lesion, which comprises less than 2% of all gestational trophoblastic proliferations. Preceding conditions include molar pregnancy (5%). Compared to choriocarcinoma or invasive mole, hemorrhage is less conspicuous and serum β-HCG level is low, making early diagnosis difficult.

Immunohistochemistry: Often stains with hPL, keratin, Mel-CAM, EGFR.

Prognosis: 10–20% of cases metastase leading to death.

Treatment: Because chemotherapy is ineffective; the patient should undergo hysterectomy.

A widely recognised method of estimating the risk of malignant ovarian cancer based on initial workup is the "risk of malignancy index" (RMI). It is recommended that women with an RMI score over 200 should be referred to a centre with experience in ovarian cancer surgery.

The RMI is calculated as follows:

There are two methods to determine the ultrasound score and menopausal score, with the resultant RMI being called RMI 1 and RMI 2, respectively, depending on what method is used:

An RMI 2 of over 200 has been estimated to have a sensitivity of 74 to 80%, a specificity of 89 to 92% and a positive predictive value of around 80% of ovarian cancer. RMI 2 is regarded as more sensitive than RMI 1.

Early diagnosis is important and today facilitated by the use of sonography and the quantitative human chorionic gonadotropin (hCG) assay. As in other cases of ectopic pregnancy, risk factors are: previous tubal pregnancy, IVF therapy, tubal surgery, and a history of sexual infection.

Typical symptoms of an interstitial pregnancy are the classic signs of ectopic pregnancy, namely abdominal pain and vaginal bleeding. Hemorrhagic shock is found in almost a quarter of patients.; this explains the relatively high mortality rate.

In pregnant patients, sonography is the primary method to make the diagnosis, even when patients have no symptoms. The paucity of myometrium around the gestational sac is diagnostic, while, in contrast, the angular pregnancy has at least 5 mm of myometrium on all of its sides. Ultrasonic criteria for the diagnosis include an empty uterine cavity, a gestational sac separate from the uterine cavity, and a myometrial thinning of less than 5 mm around the gestational sac; typically the "interstitial line sign"—an echogenic line from the endometrial cavity to the corner next to the gestational mass—is seen. MRI can be used particularly when it is important to distinguish between an interstitial and angular pregnancy.

On average, the gestational age at presentation is about 7–8 weeks. In a 2007 series, 22% of patients presented with rupture and hemorrhagic shock, while a third of the patients were asymptomatic; the remainder had abdominal pain and/or vaginal bleeding. Cases that are not diagnosed until surgery show an asymmetrical bulge in the upper corner of the uterus.

Since gestational choriocarcinoma (which arises from a hydatidiform mole) contains paternal DNA (and thus paternal antigens), it is exquisitely sensitive to chemotherapy. The cure rate, even for metastatic gestational choriocarcinoma, is around 90–95%.

At present, treatment with single-agent methotrexate is recommended for low-risk disease, while intense combination regimens including EMACO (etoposide, methotrexate, actinomycin D, cyclosphosphamide and vincristine (Oncovin) are recommended for intermediate or high-risk disease.

Hysterectomy (surgical removal of the uterus) can also be offered to patients > 40 years of age or those for whom sterilisation is not an obstacle. It may be required for those with severe infection and uncontrolled bleeding.

Choriocarcinoma arising in the testicle is rare, malignant and highly resistant to chemotherapy. The same is true of choriocarcinoma arising in the ovary. Testicular choriocarcinoma has the worst prognosis of all germ-cell cancers.

The diagnosis is made in asymptomatic pregnant women either by inspection seeing a bluish discolored cervix or, more commonly, by obstetric ultrasonography. A typical non-specific symptom is vaginal bleeding during pregnancy. Ultrasound will show the location of the gestational sac in the cervix, while the uterine cavity is "empty". Cervical pregnancy can be confused with a miscarriage when pregnancy tissue is passing through the cervix.

Histologically the diagnosis has been made by Rubin’s criteria on the surgical specimen: cervical glands are opposite the trophoblastic tissue, the trophoblastic attachment is below the entrance of the uterine vessels to the uterus or the anterior peritoneal reflection, and fetal elements are absent from the uterine corpus. As many pregnancies today are diagnosed early and no hysterectomy is performed, Rubin's criteria can often not be applied.

Cysts associated with hypothyroidism or other endocrine problems are managed by treating the underlying condition.

About 95% of ovarian cysts are benign, not cancerous.

Functional cysts and hemorrhagic ovarian cysts usually resolve spontaneously. However, the bigger an ovarian cyst is, the less likely it is to disappear on its own. Treatment may be required if cysts persist over several months, grow, or cause increasing pain.

Cysts that persist beyond two or three menstrual cycles, or occur in post-menopausal women, may indicate more serious disease and should be investigated through ultrasonography and laparoscopy, especially in cases where family members have had ovarian cancer. Such cysts may require surgical biopsy. Additionally, a blood test may be taken before surgery to check for elevated CA-125, a tumour marker, which is often found in increased levels in ovarian cancer, although it can also be elevated by other conditions resulting in a large number of false positives.

Patients with an ectopic pregnancy are generally at higher risk for a recurrence, however, there are no specific data for patients with an interstitial pregnancy. When a new pregnancy is diagnosed it is important to monitor the pregnancy by transvaginal sonography to assure that is it properly located, and that the surgically repaired area remains intact. Cesarean delivery is recommended to avoid uterine rupture during labor.

Trophoblastic neoplasms derive from trophoblastic tissue. Examples include:

- Choriocarcinoma

- Hydatidiform mole

True cervical pregnancies tend to abort; if, however, the pregnancy is located higher in the canal and the placenta finds support in the uterine cavity it can go past the first trimester. With the placenta being implanted abnormally extensive vaginal bleeding can be expected at time of delivery and placental removal. While early cervical pregnancies may abort spontaneously or can be managed with excision, D&C, suturing, electrocautery, and tamponading, by medication such as methotrexate, and/or by uterine artery embolization, a more advanced pregnancy may require a hysterectomy to control bleeding. The more advanced the pregnancy the higher the risk for a major bleeding necessitating a hysterectomy.

On a very rare occasion, a cervical pregnancy results in the birth of a live baby, typically the pregnancy is in the upper part of the cervical canal and manages to extend into the lower part of the uterine cavity.

A cervical pregnancy can develop together with a normal intrauterine pregnancy; such a heterotopic pregnancy will call for expert management as to not to endanger the intrauterine pregnancy.

Amniocentesis and chorionic villus sampling are procedures conducted to assess the fetus. A sample of amniotic fluid is obtained by the insertion of a needle through the abdomen and into the uterus. Chorionic villus sampling is a similar procedure with a sample of tissue removed rather than fluid. These procedures are not associated with pregnancy loss during the second trimester but they are associated with miscarriages and birth defects in the first trimester. Miscarriage caused by invasive prenatal diagnosis (chorionic villus sampling (CVS) and amniocentesis) is rare (about 1%).

If a small amount of bleeding is seen in early pregnancy a physician may request:

- A quantitative human chorionic gonadotropin (hCG) blood test to confirm the pregnancy or assist in diagnosing a potential miscarriage

- Transvaginal pelvic ultrasonography to confirm that the pregnancy is not outside of the uterus

- Blood type and Rh test to rule out hemolytic disease of the newborn

For bleeding seen in later pregnancy tests may include:

- Complete blood count (CBC) and blood type and screen

- Ultrasound to determine placental location

- Kleihauer-Betke (KB) test especially if there was maternal trauma

When the antepartum diagnosis of placenta accreta is made, it is usually based on ultrasound findings in the second or third trimester. Sonographic findings that may be suggestive of placenta accreta include:

1. Loss of normal hypoechoic retroplacental zone

2. Multiple vascular lacunae (irregular vascular spaces) within placenta, giving "Swiss cheese" appearance

3. Blood vessels or placental tissue bridging uterine-placental margin, myometrial-bladder interface, or crossing the uterine serosa

4. Retroplacental myometrial thickness of <1 mm

5. Numerous coherent vessels visualized with 3-dimensional power Doppler in basal view

Although there are isolated case reports of placenta accreta being diagnosed in the first trimester or at the time of abortion <20 weeks' gestational age, the predictive value of first-trimester ultrasound for this diagnosis remains unknown. Women with a placenta previa or "low-lying placenta" overlying a uterine scar early in pregnancy should undergo follow-up imaging in the third trimester with attention to the potential presence of placenta accreta.

A placental disease is any disease, disorder, or pathology of the placenta. The article also covers placentation abnormalities, which is often used synonymously for placental disease.

A review article in The New England Journal of Medicine based on a consensus meeting of the Society of Radiologists in Ultrasound in America (SRU) has suggested that miscarriage should be diagnosed only if any of the following criteria are met upon ultrasonography visualization:

Obstetric ultrasonography can detect fetal abnormalities, detect multiple pregnancies, and improve gestational dating at 24 weeks. The resultant estimated gestational age and due date of the fetus are slightly more accurate than methods based on last menstrual period. Ultrasound is used to measure the nuchal fold in order to screen for Downs syndrome.

Pregnancy detection can be accomplished using one or more various pregnancy tests, which detect hormones generated by the newly formed placenta, serving as biomarkers of pregnancy. Blood and urine tests can detect pregnancy 12 days after implantation. Blood pregnancy tests are more sensitive than urine tests (giving fewer false negatives). Home pregnancy tests are urine tests, and normally detect a pregnancy 12 to 15 days after fertilization. A quantitative blood test can determine approximately the date the embryo was conceived because HCG doubles every 36 to 48 hours. A single test of progesterone levels can also help determine how likely a fetus will survive in those with a threatened miscarriage (bleeding in early pregnancy).