Ultrasound diagnosis of cervical shortening in the follow-up of multiple pregnancy. A case report

Abstract

A 33 year old patient presented spontaneously to her prepaid medical clinic for the initiation of antenatal care (ANC), carrying only a positive home pregnancy test (hemogravindex positive). A gynecological history was obtained, revealing a past obstetrical history of two previous term pregnancies, both delivered vaginally, with no significant personal pathological history. An early first-trimester transvaginal ultrasound was performed. Initially, a diagnosis of Pregnancy of Unknown Location (PUL) was made. Uterine tubes and adnexa were assessed, and the presence of free fluid was ruled out. As the patient remained asymptomatic, a follow-up appointment was scheduled for four weeks after the completion of antenatal care documentation, to which the patient did not attend. The patient re consulted at 11 weeks of gestation, during which a follow-up ultrasound was performed using both an intracavitary probe and an abdominal transducer. This examination revealed an evident intrauterine pregnancy with the presence of three fetuses. Fetus A and Fetus B, were identified as sharing the same amniotic sac and a single placenta, while Fetus C presented its own sac and placenta. Both placentas were located high on the posterior wall. A favorable, normal cervical length of 34 mm was found. A negative functional test was performed, showing a consistency index of 80% in the absence of funneling and sludge. Elastography testing was not available at the institution. Structural study and screening for each fetus were performed according to guidelines. Antenatal controls were scheduled every two weeks with the Maternal-Fetal Medicine subspecialty.