葡萄胎：癥狀、風險及治療
根據(jù)《人的基因序列變化與人體疾病表征》，葡萄胎是由于受精過程中的基因序列而引起胡子宮內(nèi)組織異常增生。很少涉及到發(fā)育的胚胎。與正常的胚胎相比，病態(tài)組織生長很快，形成一塊大而隨機排列的類似于葡萄串的組織。葡萄胎有兩種，一種是有效葡萄胎，一種是部分葡萄胎。根據(jù)佳學(xué)基因統(tǒng)計，葡萄胎的發(fā)病率為千分之一。
什么是葡萄胎？
葡萄胎妊娠是胎盤的一種異常，是由于受精時卵子和精子結(jié)合在一起而引起的。也被稱為妊娠滋養(yǎng)細胞疾病（GTD），葡萄胎或簡單地稱為“葡萄胎”，這是一種罕見的生殖健康疾病。發(fā)病率為1/1000。
什么是有效葡萄胎？
有效葡萄胎只有胎盤部分，沒有胚胎。是精子與空卵子受精形成的。因為卵泡是空的，所以沒有胚胎發(fā)育。胎盤生長并產(chǎn)生妊娠激素hCG。但是，超聲波檢查發(fā)現(xiàn)沒有胎兒，只有胎盤。
What is a partial molar pregnancy?
- Partial Mole occurs when the mass contains both the abnormal cells and an embryo that has severe birth defects. In this case, the fetus will be overcome by the growing abnormal mass rather quickly.
- An extremely rare version of a partial mole is when twins are conceived but one embryo begins to develop normally while the other is a mole. In these cases, the healthy embryo will very quickly be consumed by the abnormal growth.
Who is at risk?
- In the US, approximately 1 out of 1,000 pregnancies is a molar pregnancy
- Mexico, Southeast Asia, and the Philippines have higher rates than the US for molar pregnancies in women
- White women in the US are at higher risk than black women
- Women over the age of 40
- Women who have had a prior molar pregnancy
- Women with a history of miscarriage
What are the symptoms?
- Vaginal spotting or bleeding
- Nausea and vomiting
- Develop rare complications like thyroid disease
- Early preeclampsia (high blood pressure)
- Increased hCG levels
- No fetal movement or heart tone detected
How do I know if I have a molar pregnancy?
- A pelvic exam may reveal a larger or smaller uterus, enlarged ovaries, and abnormally high amounts of the pregnancy hormone hCG.
- A sonogram will often show a “cluster of grapes” appearance, signifying an abnormal placenta.
How is this treated?
- Most molar pregnancies will spontaneously end and the expelled tissue will appear grape-like.
- Molar pregnancies are removed by suction curettage, dilation, and evacuation (D & C), or sometimes through medication. A general anesthetic is normally used during these procedures.
- Approximately 90% of women who have a mole removed require no further treatment.
- Follow-up procedures that monitor the hCG levels can occur monthly for six months or as your physician prescribes.
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Follow-up is done to ensure that the mole has been removed completely. Traces of the mole can begin to grow
again and may possess a cancerous-type threat to other parts of the body. - Women should avoid becoming pregnant for one year after diagnosis.
- Any birth control method is acceptable with the exception of an intrauterine device.
How will I feel emotionally after a molar pregnancy?
Although the removal of a molar pregnancy is not the termination of a developing child, it is still a loss. Even when an embryo is present, it does not have the opportunity to develop into a child. Most women discover that they are dealing with a molar pregnancy after the discovery and anticipation of being pregnant. Dreams, plans, and hopes are canceled all at once; it is still a significant loss.
Hydatidiform mole, occurring in 13 of 1000 pregnancies (25), typically occur in women during the reproductive period, although rarely occur in postmenopausal women. Hydatiform moles can be complete (CHM), partial (PHM) or invasive. CMH diffusely involves the placenta with marked villous swelling, cyst formation, circumferential villous trophoblastic hyperplasia, central villous cistern formation, random karyorrhexis, without formation of an embryo- except for embryonic capillaries in the chorionic villi (52) (Figure 5). CHM are usually diploid (46,XX,46,XY), and androgenic (52,53,54). Most (80%) are of androgenic CMHs are due to haploid genomic duplication of a sperm, the remainder (20%) are due to double sperm fertilization of the egg. The fate of the maternal genome in a CHM is still unclear. A meiosis II error was assumed to produce an anuclear egg, then fertilized by one or two sperm, but anuclear oocytes have never been documented under natural circumstances. Recently a diploidization of a triploid conceptus has been proposed as an alternative explanation (Figure 6) (55). Despite the androgenetic nature of the nuclear genome in CHM, the mitochondrial DNA is maternally derived (52).
PHMs demonstrate slow hydatidiform change, affecting only some of the placental villi. Morphologically, two populations of villi exist. Some of the villi are enlarged hydropic villi (3–4mm in diameter)with central cistern formation, and some villi are small, sclerotic, and normally sized. The hydropic villi have indented or scalloped outlines with trophoblastic pseudoinclusions.
Villous surfaces may have many tiny projections of syncytiotrophoblast, which form notches. The trophoblast hyperplasia is random and focal, nuclear atypia is infrequent,and villous stromal blood vessels containing nuclear red blood cells and/or fetal tissues may be present (Figure 7).Most PMHs are triploid (69, XXX, 69, XXY, or 69, XYY) with a paternal origin of the additional haploid genome.Most diandric triploid PHMs arise from dual sperm fertilization, less frequently due to fertilization by a diploid sperm(53). It is debatable whether a true diploid PMH exists, as those reported may represent misdiagnosed hydropic diploid miscarriages, twin pregnancies, undetected mosaic cases, or early CHMs (Figure 8). The most significant clinical consequence with complete molar pregnancies is the risk of persistent gestational trophoblastic disease or choriocarcinoma. Complete moles carry a
higher risk for developing persistent GTD or choriocarcinoma than partial moles.
(責任編輯：佳學(xué)基因)
