<P> In the case of blood loss, pain, or both, transvaginal ultrasound is performed . If a viable intrauterine pregnancy is not found with ultrasound, blood tests (serial βHCG tests) can be performed to rule out ectopic pregnancy, which is a life - threatening situation . </P> <P> If hypotension, tachycardia, and anemia are discovered, exclusion of an ectopic pregnancy is important . </P> <P> A miscarriage may be confirmed by an obstetric ultrasound and by the examination of the passed tissue . When looking for microscopic pathologic symptoms, one looks for the products of conception . Microscopically, these include villi, trophoblast, fetal parts, and background gestational changes in the endometrium . When chromosomal abnormalities are found in more than one miscarriage, genetic testing of both parents may be done . </P> <P> 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: </P>

List and define five types of naturally occurring abortions