From the Guidelines
For a 16-week threatened abortion, the most critical investigations include a transvaginal or transabdominal ultrasound to confirm fetal viability, placental location, and assess for any structural abnormalities, as well as blood typing and Rh factor determination to identify potential need for RhoGAM in Rh-negative mothers. These investigations are crucial in determining the cause of bleeding, assessing fetal well-being, and guiding appropriate management decisions 1.
Key investigations to consider include:
- A complete blood count to assess for anemia and infection
- Blood typing and Rh factor determination to identify potential need for RhoGAM in Rh-negative mothers
- Transvaginal or transabdominal ultrasound to confirm fetal viability, placental location, and assess for any structural abnormalities
- Quantitative serum hCG levels may be measured to establish a baseline, though they are less useful at this gestational age
- Cervical assessment should be performed to evaluate for cervical dilation or effacement
- Additional tests include urinalysis and urine culture to rule out urinary tract infection, coagulation studies if there is heavy bleeding, and screening for infections like chlamydia and gonorrhea that could contribute to pregnancy complications.
It is essential to monitor the patient's vital signs and document the extent of vaginal bleeding. If the mother is Rh-negative and the bleeding is significant, administration of RhoGAM should be considered to prevent Rh sensitization, with a recommended dose of 50 μg or 300 mcg depending on the severity of the bleeding and gestational age 1.
In the context of a 16-week threatened abortion, it is crucial to prioritize investigations that assess fetal viability, placental location, and potential causes of bleeding, while also considering the mother's Rh status and potential need for RhoGAM to prevent Rh sensitization 1.
From the Research
Investigations for 16-Week Threatened Abortion
Investigations for a 16-week threatened abortion may include:
- Ultrasound scanning to confirm fetal viability and detect any potential complications 2, 3, 4
- Hormone assays, such as serum estradiol and progesterone levels, to assess fetal well-being 2
- Clinical evaluation, including assessment of vaginal bleeding and uterine cramping 5, 6
Ultrasound Scanning
Ultrasound scanning is a crucial investigation in threatened abortion, as it can:
- Confirm fetal viability and detect fetal heart movements 2, 3, 4
- Identify potential complications, such as embryonic death or anembryonic pregnancy 4
- Provide information on gestational age and fetal development 3, 4
Hormone Assays
Hormone assays, such as serum estradiol and progesterone levels, can:
- Assess fetal well-being and predict pregnancy outcome 2
- Identify potential hormonal imbalances that may be contributing to the threatened abortion 5
Clinical Evaluation
Clinical evaluation is essential in threatened abortion, as it can: