Products of conception, abbreviated POC, is a medical term used for the tissue derived from the union of an egg and a sperm. It encompasses anembryonic gestation (blighted ovum) which does not have a viable embryo.
In the context of tissue from a dilation and curettage, the presence of POC essentially excludes an ectopic pregnancy.
Retained products of conception is where products of conception remain in the uterus after childbirth, medical abortion or miscarriage (also known as spontaneous abortion). [1] Miscarriage with retained products of conception is termed delayed when no or very little products of conception have been passed, and incomplete when some products have been passed but some still remain in utero . [2] [3]
The diagnosis is based on clinical presentation, quantitative HCG, ultrasound, and pathologic evaluation. A solid, heterogeneous, echogenic mass has a positive predictive value of 80%, but is present in only a minority of cases. A thickened endometrium of > 10 mm is usually considered abnormal, though no consensus exists on the appropriate cutoff. A cut-off of 8 mm or more has 34% positive rate, while a cut off of 14 mm or more has 85% sensitivity, 64% specificity for the diagnosis. Color Doppler flow in the endometrial canal can increased confidence in the diagnosis, though its absence does not exclude it, as 40% of cases of retained products have little or no flow. The differential in suspected cases includes uterine atony, blood clot, gestational trophoblastic disease, and normal post partum appearance of the uterus. Post partum blood clot is more common, reported in up to 24% of postpartum patients, and tends to be more hypoechoic than retained products with absent color flow on Doppler, and resolving spontaneously on follow up scans. The presence of gas raises the possibility of post partum endometritis, though this can also be seen in up to 21% of normal post pregnancy states. The normal post partum uterus is usually less than 2 cm in thickness, and continues to involute on follow up scans to 7 mm or less over time. Retained products are not uncommon, occurring in approximately 1% of all pregnancies, though it more common following abortions, either elective or spontaneous. There is significant overlap between appearance of a normal post partum uterus and retained products. If there is no endometrial canal mass or fluid, and endometrial thickness is less than 10 mm and without increased flow, retained products are statistically unlikely. [4] [5] [6]
Recent studies indicate that the products of conception may be susceptible to pathogenic infections, [7] including viral infections. Indeed, footprints of JC polyomavirus and Merkel cell polyomavirus have been detected in chorionic villi from females affected by spontaneous abortion as well as pregnant women. [8] [9] Another virus, BK polyomavirus has been detected in the same tissues, but with lesser extent. [8]
According to the 2006 WHO Frequently asked clinical questions about medical abortion, [10] the presence of remaining products of conception in the uterus (as detected by obstetric ultrasonography) after a medical abortion is not an indication for surgical intervention (that is, vacuum aspiration or dilation and curettage). Remaining products of conception will be expelled during subsequent vaginal bleeding. Still, surgical intervention may be carried out on the woman's request, if the bleeding is heavy or prolonged, or causes anemia, or if there is evidence of endometritis.
In delayed miscarriage (also called missed abortion), the Royal Women's Hospital recommendations of management depend on the findings in ultrasonography: [11]
In incomplete miscarriage, the Royal Women's Hospital recommendations of management depend on the findings in ultrasonography: [11]
Dilationand curettage (D&C) refers to the dilation of the cervix and surgical removal of part of the lining of the uterus or contents of the uterus by scraping and scooping (curettage). It is a gynecologic procedure used for diagnostic and therapeutic purposes, and is the most commonly used method for first-trimester miscarriage or abortion.
Ectopic pregnancy is a complication of pregnancy in which the embryo attaches outside the uterus. Signs and symptoms classically include abdominal pain and vaginal bleeding, but fewer than 50 percent of affected women have both of these symptoms. The pain may be described as sharp, dull, or crampy. Pain may also spread to the shoulder if bleeding into the abdomen has occurred. Severe bleeding may result in a fast heart rate, fainting, or shock. With very rare exceptions, the fetus is unable to survive.
Miscarriage, also known in medical terms as a spontaneous abortion, is the death and expulsion of an embryo or fetus before it can survive independently. The term miscarriage is sometimes used to refer to all forms of pregnancy loss and pregnancy with abortive outcomes before 20 weeks of gestation.
The chorion is the outermost fetal membrane around the embryo in mammals, birds and reptiles (amniotes). It develops from an outer fold on the surface of the yolk sac, which lies outside the zona pellucida, known as the vitelline membrane in other animals. In insects it is developed by the follicle cells while the egg is in the ovary. Some mollusks also have chorions as part of their eggs. For example fragile octopus eggs have only a chorion as their envelope.
Misoprostol is a synthetic prostaglandin medication used to prevent and treat stomach and duodenal ulcers, induce labor, cause an abortion, and treat postpartum bleeding due to poor contraction of the uterus. It is taken by mouth when used to prevent gastric ulcers in people taking nonsteroidal anti-inflammatory drugs (NSAID). For abortions it is used by itself or in conjunction with mifepristone or methotrexate. By itself, effectiveness for abortion is between 66% and 90%. For labor induction or abortion, it is taken by mouth, dissolved in the mouth, or placed in the vagina. For postpartum bleeding it may also be used rectally.
Human polyomavirus 2, commonly referred to as the JC virus or John Cunningham virus, is a type of human polyomavirus. It was identified by electron microscopy in 1965 by ZuRhein and Chou, and by Silverman and Rubinstein, and later isolated in culture and named using the two initials of a patient, John Cunningham, with progressive multifocal leukoencephalopathy (PML). The virus causes PML and other diseases only in cases of immunodeficiency, as in AIDS or during treatment with immunosuppressive drugs.
Asherman's syndrome (AS) is an acquired uterine condition that occurs when scar tissue (adhesions) forms inside the uterus and/or the cervix. It is characterized by variable scarring inside the uterine cavity, where in many cases the front and back walls of the uterus stick to one another. AS can be the cause of menstrual disturbances, infertility, and placental abnormalities. Although the first case of intrauterine adhesion was published in 1894 by Heinrich Fritsch, it was only after 54 years that a full description of Asherman syndrome was carried out by Joseph Asherman. A number of other terms have been used to describe the condition and related conditions including: uterine/cervical atresia, traumatic uterine atrophy, sclerotic endometrium, and endometrial sclerosis.
Adenomyosis is a medical condition characterized by the growth of cells that proliferate on the inside of the uterus (endometrium) atypically located among the cells of the uterine wall (myometrium), as a result, thickening of the uterus occurs. As well as being misplaced in patients with this condition, endometrial tissue is completely functional. The tissue thickens, sheds and bleeds during every menstrual cycle.
Vaginal bleeding is any expulsion of blood from the vagina. This bleeding may originate from the uterus, vaginal wall, or cervix. Generally, it is either part of a normal menstrual cycle or is caused by hormonal or other problems of the reproductive system, such as abnormal uterine bleeding.
An endometrial polyp or uterine polyp is a mass in the inner lining of the uterus. They may have a large flat base (sessile) or be attached to the uterus by an elongated pedicle (pedunculated). Pedunculated polyps are more common than sessile ones. They range in size from a few millimeters to several centimeters. If pedunculated, they can protrude through the cervix into the vagina. Small blood vessels may be present, particularly in large polyps.
Obstetrical bleeding is bleeding in pregnancy that occurs before, during, or after childbirth. Bleeding before childbirth is that which occurs after 24 weeks of pregnancy. Bleeding may be vaginal or less commonly into the abdominal cavity. Bleeding which occurs before 24 weeks is known as early pregnancy bleeding.
Vacuum or suction aspiration is a procedure that uses a vacuum source to remove an embryo or fetus through the cervix. The procedure is performed to induce abortion, as a treatment for incomplete spontaneous abortion or retained fetal and placental tissue, or to obtain a sample of uterine lining. It is generally safe, and serious complications rarely occur.
Dilation and evacuation (D&E) is the dilation of the cervix and surgical evacuation of the uterus after the first trimester of pregnancy. It is a method of abortion as well as a common procedure used after miscarriage to remove all pregnancy tissue.
A peripheral blood mononuclear cell (PBMC) is any peripheral blood cell having a round nucleus. These cells consist of lymphocytes and monocytes, whereas erythrocytes and platelets have no nuclei, and granulocytes have multi-lobed nuclei. In humans, lymphocytes make up the majority of the PBMC population, followed by monocytes, and only a small percentage of dendritic cells.
The BK virus, also known as Human polyomavirus 1, is a member of the polyomavirus family. Past infection with the BK virus is widespread, but significant consequences of infection are uncommon, with the exception of the immunocompromised and the immunosuppressed. BK virus is an abbreviation of the name of the first patient, from whom the virus was isolated in 1971.
Chorionic villi are villi that sprout from the chorion to provide maximal contact area with maternal blood.
Chorionic hematoma is the pooling of blood (hematoma) between the chorion, a membrane surrounding the embryo, and the uterine wall. It occurs in about 3.1% of all pregnancies, it is the most common sonographic abnormality and the most common cause of first trimester bleeding.
An interstitial pregnancy is a uterine but ectopic pregnancy; the pregnancy is located outside the uterine cavity in that part of the fallopian tube that penetrates the muscular layer of the uterus. The term cornual pregnancy is sometimes used as a synonym, but remains ambiguous as it is also applied to indicate the presence of a pregnancy located within the cavity in one of the two upper "horns" of a bicornuate uterus. Interstitial pregnancies have a higher mortality than ectopics in general.
Definitions of abortion vary from one source to another. Abortion has many definitions that can differ from each other in significant ways. Given the contentious nature of abortion, lawmakers and other stakeholders often face controversy in defining abortion. Language referring to abortion often reflects societal and political opinions . Influential non-state actors like the United Nations and the Roman Catholic Church have also engendered controversy over efforts to define abortion.
Early pregnancy bleeding refers to vaginal bleeding before 14 weeks of gestational age. If the bleeding is significant, hemorrhagic shock may occur. Concern for shock is increased in those who have loss of consciousness, chest pain, shortness of breath, or shoulder pain.