gynecology and obstetrics
Spontaneous Abortion
Diagnosis of Spontaneous Abortion
Transvaginal ultrasonography Quantitative beta subunit ofhuman chorionic gonadotropin(beta-hCG) Pelvic examination Pregnancy is diagnosed with a urine or serum beta-hCG test. Transvaginal ultrasonography is the main method used to evaluate for spontaneous abortion. If ultrasonography is not available, hCG results may be informative. There is no single hCG level that is diagnostic of spontaneous abortion; serial beta-hCG levels that decrease across several measurements are consistent with a failed pregnancy. Transvaginal ultrasonography is performed to confirm intrauterine pregnancy and check for fetal cardiac activity, which is usually detectable after 5.5 to 6 weeks gestation. However, gestational age is often somewhat uncertain, and serial ultrasonography is often required. If cardiac activity is absent and had been detected previously during the current pregnancy, fetal demise is diagnosed. In early pregnancy, for patients with suspected spontaneous abortion, transvaginal ultrasound findings diagnostic of pregnancy failure are one or more of the following ( Diagnosis reference ): Crown-rump length ≥ 7 mm and no heartbeat Mean sac diameter ≥ 25 mm and no embryo Absence of an embryo with a heartbeat, after a previous scan in current pregnancy: ≥ 2 weeks earlier that showed a gestational sacwithouta yolk sac OR ≥ 11 days earlier in the current pregnancy that showed a gestational sacwitha yolk sac There are many ultrasound findings that raise suspicion for but are not diagnostic of pregnancy failure, including characteristics of the gestational or yolk sac, absence of embryo or heartbeat, and crown-rump length. If these findings are present, serial evaluation is required to confirm whether a pregnancy is viable. Traditionally, the status of the abortion process is classified as follows: Threatened abortion:Patients have uterine bleeding and it is too early to assess whether the fetus is alive and viable and the cervix is closed. Potentially, the pregnancy may continue without complications. Inevitable abortion:The cervix is dilated. If the cervix is dilated, the volume of bleeding should be evaluated because it is sometimes significant. Incomplete abortion:The products of conception are partially expelled. Complete abortion:The products of conception have passed and the cervix is closed (see table). Missed abortion:Death of an embryo or a fetus is confirmed, but there is no bleeding or cervical dilation and the products of conception have not been expelled. Ananembryonic pregnancy(formerly blight ovum) refers to a nonviable pregnancy with a gestational sac, but with no yolk sac or embryo visualized on transvaginal ultrasonography. Recurrent Pregnancy Loss None Vaginal Bleeding During Early Pregnancy is common in early pregnancy (for differential diagnosis, see table Pelvic Pain During Early Pregnancy or pressure is also a common pregnancy symptom (see table 1.Doubilet PM, Benson CB, Bourne T, et al: Diagnostic criteria for nonviable pregnancy early in the first trimester.N Engl J Med369(15):1443-1451, 2013. doi:10.1056/NEJMra1302417 