GESTATIONAL SAC TO CRL RATIO AS A PROGNOSTIC MARKER IN EARLY PREGNANCY: TWO CASE REPORTS

Ivanna Ilkiv; Agata   Kucharska; Patrycja  Stanowska; Konrad  Adler; Zuzanna  Gebert; Agnieszka  Zaręba; Dawid  Juszkiewicz; Krzysztof   Kiełczewski; Barbara  Fetner; Magdalena   Dłużewska

doi:10.31435/ijitss.2(50).2026.5704

Authors

Ivanna Ilkiv Nowodworskie Medical Center, Nowy Dwór Mazowiecki, Poland https://orcid.org/0009-0008-4223-3976
Agata Kucharska Rey-Dent Holistic Dentistry Practice, Warsaw, Poland https://orcid.org/0009-0009-9840-4911
Patrycja Stanowska Silesian Academy, Faculty of Medical Sciences in Zabrze, Zabrze, Poland https://orcid.org/0009-0003-9100-1948
Konrad Adler Czerniakowski Hospital, Warsaw, Poland https://orcid.org/0009-0006-9483-7072
Zuzanna Gebert Międzyleski Specialist Hospital, Warsaw, Poland https://orcid.org/0009-0000-6169-5799
Agnieszka Zaręba Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0001-9890-8310
Dawid Juszkiewicz Medical University of Gdańsk, Gdańsk, Poland https://orcid.org/0009-0003-3392-8024
Krzysztof Kiełczewski Medical University of Warsaw, Warsaw, Poland https://orcid.org/0009-0009-6159-4598
Barbara Fetner Medical University of Silesia, Faculty of Medical Sciences in Zabrze, Zabrze, Poland https://orcid.org/0009-0006-9413-9901
Magdalena Dłużewska Healthcare Center in Cieszyn, Cieszyn, Poland https://orcid.org/0009-0006-5006-9112

DOI:

https://doi.org/10.31435/ijitss.2(50).2026.5704

Keywords:

Early Pregnancy Ultrasound, Gestational Sac (GS), Crown–Rump Length (CRL), GS–CRL Ratio, First-Trimester Pregnancy Loss, Pregnancy Viability

Abstract

The aim of this study was to assess whether the relationship between gestational sac (GS) size and crown–rump length (CRL) may have value in predicting early pregnancy outcome.

We report two cases of early intrauterine pregnancy with initially normal ultrasound findings, including the presence of embryonic cardiac activity. Both patients underwent serial transvaginal ultrasound examinations in the first trimester, with measurement of GS, CRL and yolk sac, as well as derived indices including GS–CRL difference and GS/CRL ratio.

In both cases, early scans were reassuring. However, in follow-up examinations the gestational sac failed to keep pace with embryonic growth, resulting in a progressive mismatch between GS and CRL. This preceded pregnancy loss despite previously normal viability parameters. One case was additionally complicated by a subchorionic hematoma, while in the second a relatively small gestational sac was noted before diagnosis of missed miscarriage.

These cases suggest that an unfavorable GS–CRL relationship may precede early pregnancy loss even when cardiac activity is present. The observation is preliminary and requires confirmation in larger prospective studies.

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