Vaginal Bleeding During Pregnancy Linked to Spontaneous Abortion Risk

A recent study published in the American Journal of Obstetrics & Gynecology sheds light on the increased risk of spontaneous abortion associated with vaginal bleeding during early pregnancy, particularly when accompanied by certain ultrasound findings. The research underscores the importance of combining clinical symptoms with ultrasound measurements to accurately assess the risk of spontaneous abortion in women with a history of infertility.

Led by Dr. Meridith P. Pollie and colleagues from Penn Medicine at the University of Pennsylvania Health System, the study aimed to evaluate the correlation between vaginal bleeding, first-trimester ultrasound measurements, and the risk of spontaneous abortion in women undergoing embryo transfer due to infertility.

The retrospective cohort study analyzed data from 1,858 women who underwent autologous embryo transfer and experienced a singleton intrauterine pregnancy between 2017 and 2019. Here are the key findings:

● 17% of women reported vaginal bleeding or spotting before 8 weeks of gestation.

● Overall, there were 359 cases of spontaneous abortion and 1,499 live births in the cohort.

Ultrasound Findings and Spontaneous Abortion Risk

The study found that vaginal bleeding combined with specific ultrasound measurements had a significant impact on the risk of spontaneous abortion:

● Women with bleeding and absent fetal heart rate with fetal pole on ultrasound had a 60% risk of spontaneous abortion compared to 9.5% in those without (Relative Risk [RR] = 5.36).

● The highest spontaneous abortion incidence was observed in women with bleeding, absent fetal heart rate, and absent fetal pole (95.8% vs. 9.5%; RR = 9.67).

● Those with bleeding and either low fetal heart rate or low crown-rump length at 7 weeks gestation had a 23.1% risk of spontaneous abortion compared to 5.1% in those without (RR = 5.09).

● The highest risk (84.2%) was seen in women with bleeding and both abnormally low fetal heart rate and crown-rump length (RR = 14.82).

The study highlights the importance of combining clinical symptoms with ultrasound parameters to accurately assess the risk of spontaneous abortion. Patients with vaginal bleeding and normal ultrasound measurements had a similar spontaneous abortion risk to those without bleeding at 6 and 7 weeks gestation. This information can help reassure patients with normal ultrasound measurements and identify those with abnormal sonographic measurements who may be at higher risk for spontaneous abortion, aiding in counselling and decision-making.

The findings emphasize the significance of a comprehensive approach to patient care, considering both clinical symptoms and ultrasound data, to effectively manage the risk of spontaneous abortion in women with a history of infertility during early pregnancy.

Reference:

Pollie, M. P., Romanski, P. A., Bortoletto, P., & Spandorfer, S. D. (2023). Combining early pregnancy bleeding with ultrasound measurements to assess spontaneous abortion risk among infertile patients. American Journal of Obstetrics and Gynecology. https://doi.org/10.1016/j.ajog.2023.07.031.