Ectopic pregnancy

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. 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.Transvaginal ultrasonography of an ectopic pregnancy, showing the field of view in the following image.A 'blob sign', which consists of the ectopic pregnancy. The ovary is distinguished from it by having follicles, whereof one is visible in the field. This patient had an intrauterine device (IUD) with progestogen, whose cross-section is visible in the field, leaving an ultrasound shadow distally to it.Ultrasound image showing an ectopic pregnancy where a gestational sac and fetus has been formed.embryo (with or without cardiac activity).Leg of fetal lamb appearing out of the uterus during caesarian section.External view of fetal sac, necrotic distal part.Internal view of fetal sac, before resection of distal necrotic part.Internal view of fetal sac, the necrotic distal part is to the left.External side of fetal sac, proximal end, with ovary and uterine horn.Resected distal part of fetal sac, with attached placenta. 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. 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. Risk factors for ectopic pregnancy include: pelvic inflammatory disease, often due to chlamydia infection, tobacco smoking, prior tubal surgery, a history of infertility, and the use of assisted reproductive technology. Those who have previously had an ectopic pregnancy are at much higher risk of having another one. Most ectopic pregnancies (90%) occur in the fallopian tube, which are known as tubal pregnancies. Implantation can also occur on the cervix, ovaries, or within the abdomen. Detection of ectopic pregnancy is typically by blood tests for human chorionic gonadotropin (hCG) and ultrasound. This may require testing on more than one occasion. Ultrasound works best when performed from within the vagina. Other causes of similar symptoms include: miscarriage, ovarian torsion, and acute appendicitis. Prevention is by decreasing risk factors such as chlamydia infections through screening and treatment. While some ectopic pregnancies will resolve without treatment, this approach has not been well studied as of 2014. The use of the medication methotrexate works as well as surgery in some cases. Specifically it works well when the beta-HCG is low and the size of the ectopic is small. Surgery is still typically recommended if the tube has ruptured, there is a fetal heartbeat, or the person's vital signs are unstable. The surgery may be laparoscopic or through a larger incision, known as a laparotomy. Outcomes are generally good with treatment. The rate of ectopic pregnancy is about 1% and 2% that of live births in developed countries, though it may be as high as 4% among those using assisted reproductive technology. It is the most common cause of death among women during the first trimester at approximately 10% of the total. In the developed world outcomes have improved while in the developing world they often remain poor. The risk of death among those in the developed world is between 0.1 and 0.3 percent while in the developing world it is between one and three percent. The first known description of an ectopic pregnancy is by Al-Zahrawi in the 11th century. The word 'ectopic' means 'out of place'. Up to 10% of women with ectopic pregnancy have no symptoms, and one third have no medical signs. In many cases the symptoms have low specificity, and can be similar to those of other genitourinary and gastrointestinal disorders, such as appendicitis, salpingitis, rupture of a corpus luteum cyst, miscarriage, ovarian torsion or urinary tract infection. Clinical presentation of ectopic pregnancy occurs at a mean of 7.2 weeks after the last normal menstrual period, with a range of four to eight weeks. Later presentations are more common in communities deprived of modern diagnostic ability. Signs and symptoms of ectopic pregnancy include increased hCG, vaginal bleeding (in varying amounts), sudden lower abdominal pain, pelvic pain, a tender cervix, an adnexal mass, or adnexal tenderness. In the absence of ultrasound or hCG assessment, heavy vaginal bleeding may lead to a misdiagnosis of miscarriage. Nausea, vomiting and diarrhea are more rare symptoms of ectopic pregnancy. Rupture of an ectopic pregnancy can lead to symptoms such as abdominal distension, tenderness, peritonism and hypovolemic shock. A woman with ectopic pregnancy may be excessively mobile with upright posturing, in order to decrease intrapelvic blood flow, which can lead to swelling of the abdominal cavity and cause additional pain. The most common complication is rupture with internal bleeding which may lead to hypovolemic shock. Death from rupture is the leading cause of death in the first trimester of the pregnancy. There are a number of risk factors for ectopic pregnancies. However, in as many as one third to one half no risk factors can be identified. Risk factors include: pelvic inflammatory disease, infertility, use of an intrauterine device (IUD), previous exposure to diethylstilbestrol (DES), tubal surgery, intrauterine surgery (e.g. D&C), smoking, previous ectopic pregnancy, endometriosis, and tubal ligation. A previous induced abortion does not appear to increase the risk. The intrauterine device (IUD) does not increase the risk of ectopic pregnancy, but with an IUD if pregnancy occurs it is more likely to be ectopic than intrauterine. The risk of ectopic pregnancy after chlamydia infection is low. The exact mechanism through which chlamydia increases the risk of ectopic pregnancy is uncertain, though some research suggests that the infection can affect the structure of Fallopian tubes.