From the Guidelines
An inevitable abortion is typically indicated when the cervical os is open, but the situation can still be considered a threatened abortion in some cases, depending on the degree of cervical dilation and other clinical factors, as suggested by the most recent guidelines from the Society of Radiologists in Ultrasound consensus conference recommendations 1. The distinction between a threatened and inevitable abortion depends on various clinical factors, including the degree of cervical dilation, gestational age, and presence of bleeding or cramping.
- If the cervix is only slightly open (1-2 cm), especially in early pregnancy, and there are no other concerning symptoms, it may still be classified as a threatened abortion.
- However, if the cervix is more widely dilated (3 cm or more), there's significant bleeding, or products of conception are visible, it's more likely to be an inevitable abortion. According to the American Journal of Obstetrics and Gynecology, the terms "early pregnancy loss" and "cardiac activity" are preferred to describe sonographic findings in the first trimester, replacing terms such as "failure" and "heart motion" 1. Healthcare providers should perform a thorough evaluation, including ultrasound, to determine the viability of the pregnancy and the appropriate classification, as outlined in the Society of Radiologists in Ultrasound consensus conference recommendations 1. It's essential to note that even with a slightly open cervix, the prognosis is guarded, and close monitoring is crucial, with patients advised to rest, avoid sexual activity, and report any changes in symptoms immediately, based on the most recent guidelines 1.
From the Research
Definition of Inevitable Abortion
An inevitable abortion is a condition where the cervix is open, and there is vaginal bleeding, indicating that a miscarriage is imminent or has already occurred 2.
Cervical Os and Abortion
When the cervical os is open, it can be a sign of an inevitable abortion, as the cervix is dilated, and the pregnancy is no longer viable 2. However, in some cases, a cervical polyp can cause bleeding and be misdiagnosed as an inevitable abortion, even when the cervical os is open 3.
Threatened Abortion
A threatened abortion, on the other hand, is characterized by bleeding and/or uterine cramping while the cervix is closed 4. This condition may progress to spontaneous incomplete or complete abortion.
Key Differences
The key difference between an inevitable abortion and a threatened abortion is the state of the cervical os. If the cervical os is open, it is likely an inevitable abortion, whereas a closed cervix indicates a threatened abortion 4, 2.
Management and Treatment
Treatment for threatened abortion is feasible in cases with maternal factors, such as surgical procedures, correction of genital tract abnormalities, and treatment of maternal diseases 4. However, in cases of inevitable abortion, treatment is focused on managing bleeding and preventing complications 2.
Complications and Risks
Inevitable abortion can lead to complications such as hemorrhagic shock, as seen in a case where a patient presented with hypotensive shock due to an incomplete abortion 2. In such cases, prompt medical attention and evacuation of the retained products of conception can help prevent further complications.
Cervical Stenosis and Hysteroscopy
Cervical stenosis can pose a challenge during hysteroscopic procedures, making it difficult to enter the uterine cavity 5. However, techniques such as using a uterine palpator, grasper, or scissors to gently probe the cervix can help identify the external cervical os and overcome stenosis.