Uterine pregnancy

The device prevents uterine pregnancy but it does not prevent ovulation or ectopic (implantation of the fertilized egg outside of the uterus) pregnancy. 

Major clinical hazard, mifepristone. This prostaglandin analog is capable of inducing abortion of a uterine pregnancy of less than 49 days duration when administered orally. In 2000, it was approved in the United States amidst controversy associated with the cultural aspects of pregnancy and its termination. 

Extra-uterine pregnancy appears to be increasingly frequent (145), and the cause of this increase has yet to be determined. It was to be expected that suspicion would fall upon new forms of contraception, especially where the mode of action is such that an interference with tubal transport can occur. Various studies point to the intra-uterine de-... 

Beneficial effects have also been attributed to PAF. In reproduction, PAF secreted by the fertilized egg is instrumental in the implantation of the egg in the uterine wall. PAF is produced in significant quantities in the lungs of the fetus late in pregnancy and may stimulate the production of fetal lung surfactant, a protein-lipid complex that prevents collapse of the lungs in a newborn infant. 

The first SPRM to reach the advanced stage of clinical development for treatment of endometriosis and uterine fibroids, asoprisnil, is expected to receive FDA approval this year. The therapeutic effect of asoprisnil stems from its PR antagonist/ antiproliferative activity in the endometrium and breast. Unlike classical PR antagonists however, this compound does not induce labor in animal models of pregnancy and parturition. Recent structural studies... 

History of any estrogen-dependent neoplasm Undiagnosed abnormal uterine bleeding Pregnancy (known or suspected)... 

There are potential side effects of IUD use. The most common adverse effects are cramping, abnormal uterine bleeding, and expulsion of the device. Other side effects seen are ectopic pregnancy, sepsis, PID, embedment of the device, uterine or cervical perforation, and ovarian cysts.40,41... 

Ectopic pregnancy Presence of a fertilized ovum outside the uterine cavity. 

Luteolysis The structural and functional degradation of the corpus luteum that occurs at the end of the luteal phase in the absence of pregnancy caused by the hormones prostaglandin-2(X and oxytocin. Communication between the corpus luteum and uterine endometrium is necessary for luteolysis. 

Initial investigations of these devices led to the conclusion that the larger the device, the more effective it was in preventing pregnancy. Large devices, however, increased the possibility of uterine cramps, bleeding, and expulsion of the device. 

Contraception is the prevention of pregnancy following sexual intercourse by inhibiting sperm from reaching a mature ovum (i.e., methods that act as barriers or prevent ovulation) or by preventing a fertilized ovum from implanting in the endometrium (i.e., mechanisms that create an unfavorable uterine environment). 

Parkington HC, Tonta MA, Brennecke SP, Coleman HA 1999 Contractile activity, membrane potential, and cytoplasmic calcium in human uterine smooth muscle in the third trimester of pregnancy and during labor. Am J Obstet Gynecol 181 1445—1451... 

Zhang L, Dyer DC. (1993). Lysergic acid diethylamide is a partial agonist at 5-HT2 receptors in ovine uterine artery of late pregnancy. EurJ Pharmacol. 230(1) 115-17. 

CSF-1 is synthesized by many different cell types including fibroblasts, endothelial cells, bone marrow stromal cells, osteoblasts, keratinocytes, astrocytes, myoblasts and, during pregnancy, under the control of estrogen and progesterone, by uterine epithelial cells. Circulating CSF-1 (ti/2 = 10 min) is synthesized by endothelial cells and smooth muscle cells. It is primarily cleared by CSF-lR-mediated internalization and destruction by Kupffer cells. Thus the number of sinusoidally located macrophages actually determines the concentration of the cytokine... 

Estradiol is the most important of the estrogens. Like progesterone, it is synthesized by the ovaries and, during pregnancy, by the placenta as well. Estradiol controls the menstrual cycle, it promotes proliferation of the uterine mucosa, and is also responsible for the development of the female secondary sexual characteristics (breast, fat distribution, etc.). 

Pregnancy Category C. Reduced uterine blood flow with fetal hypoxia (bradycardia) is a potential risk. Give to a pregnant woman only if clearly needed. 

Uterine rupture has been reported when misoprostol was administered intravaginally in pregnant women to induce labor or to induce abortion beyond the first trimester of pregnancy. 

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