Early diagnosis of ectopic pregnancy using modern medical imaging techniques: prospective study

INTRODUCTION: The algorithm for diagnosing ectopic pregnancy (EP), including b-chorionic gonadotropin in the blood and ultrasound of the pelvic organs, does not allow detecting its localization in the next 7 days after treatment in 10% of women.

OBJECTIVE: Тo improve the algorithm of diagnostics of EP by correcting the ultrasound protocol, as well as adding MRI studies.

MATERIALS AND METHODS: 290 patients with suspected EP, of which 278 were operated on. Women were divided according to menstrual delay: up to 6 weeks (Group 1, n=119), 6–9 weeks (Group 2, n=135), more than 9 weeks (Group 3, n=36). Ultrasound studies were performed in dynamics up to 144 hours on the VOLUSON-730 expert (GE); MR studies — on a 1.5T tomograph «Magnetom Avanto» (Siemens). Statistics: Statistical analysis of the study results was performed using the Statistica for Windows 10.0 software package (StatSoft, Inc., USA).

RESULTS: Ultrasound symptoms of EP: group 1 (n=94) — ectopic fetal egg (EPO) and tubal ring (TC) 5 times more often than hematosalpinx (HS) and heterogeneous adnexal formation (NPO) (χ₁²=14.28; p=0.0002 and χ₂²=13.75, р=0.0003); 2 (n=116) — EPO and TC 3 times more often than GS (χ₁²1=4.8; р₁²=0.028 and χ₂²2=8.1; р₂²=0.004) and NPO (χ₁²=6.65; р₁=0.009 and χ₂²=10.4; р₂=0.001); 3 (n=31) — TC and NPO more often than EPO (χ₁²=8.00; p₁=0.004; χ₂²=14.28; p₂=0.0002). Ultrasound is not informative: group 1 — more than half of the cases; 2 — 24.5%; 3 — 65% of cases. In pregnancies of unknown location (PUL, n=30), MR patterns of EP were studied : in 1⁄3 of cases, progressive early EP was found, in 1⁄3 — undilated fallopian tubes, and in 1⁄3 of cases of HS. Sensitivity of ultrasound in relation to EP: group 1 — 42%; 2 — 76.5%; 3 — 35%; it depends on the period of menstrual delay (r=0.507, p=0.01).

DISCUSSION: In PUL, MRI is indicated for all patients who have a menstrual delay of more than 6 weeks, regardless of the level of b-HCG in their blood, and with a menstrual delay of up to 6 weeks, only if the increase in b-HCG in the blood is less than 50% of physiological values.

CONCLUSION: The inclusion of MRI in the algorithm for diagnosing EP increases its sensitivity and specificity to almost 100%, regardless of the period of menstrual delay.

1. Стрижаков А.Н., Давыдов А.И., Рубина Е.В. Беременность в рубце на матке после кесарева сечения // Вопросы гинекологии, акушерства и перинатологии. 2016. Т. 15, № 5. С. 67–72. [Strizhakov A.N., Davydov A.I., Rubina E.V. Pregnancy in a scar on the uterus after cesarean section. Questions of gynecology, obstetrics and perinatology, 2016, Vol. 15, No. 5, pp. 67–72 (In Russ.)].

2. Kathpalia S.K., Arora D., Sandhu N., Sinha P. Ectopic pregnancy: Review of 80 cases // Med. J. Armed Forces India. 2018. Apr.; No. 74 (2). P. 172–176. doi: 10.1016/j.mjafi.2016.11.004.

3. Lisonkova S., Tan J., Wen Q., Abdellatif L., Richter L.L., Alfaraj S., Yong P.J., Bedaiwy M.A. Temporal trends in severe morbidity and mortality associated with ectopic pregnancy requiring hospitalisation in Washington State, USA: a population-based study. // BMJ Open. 2019. Vol. 19, No. 9 (2). P. e024353. doi: 10.1136/bmjopen2018-024353.

4. Lavani O.L., Anozie O.B., Ezeonu P.O. Ectopic pregnancy: a life-threatening gynecological emergency // Int. J. Women’s health. 2013. Vol. 5. Р. 515–521. doi: 10.2147/IJWH. C49672. PMID: 23983494; PMCID: PMC3751381.

5. Гадаева И.В., Хохлова И.Д., Джибладзе Т.А. Внематочная (эктопическая) беременность // Архив акушерства и гинекологии им. В. Ф. Снегирева. 2020. Т. 7, № 1. C. 4–9. [Gadayeva I.V., Khokhlova I.D., Dzhibladze T.A. Ectopic pregnancy. V. F. Snegirev Archives of Obstetrics and Gynecology, 2020, Vol. 7, Nо. 1, рр. 4– 9 (In Russ.)]. doi: 10.18821/2313-8726-2020-7-1-4-9.

6. Baltarowich O.H., Scoutt L.M. Ectopic pregnancy // Norton M.E., Scoutt M.L., Feldstein V.A. Callen’s Ultrasonography in Obstetrics and Gynecology. 6th ed. California: Elsevier Health Sciences, 2016. P. 967–998.

7. Kirk E., Bottomley С., Bourne Т. Diagnosing ectopic pregnancy and current concepts in the management of pregnancy of unknown location // Human Reproduction Update. 2014. Vol. 20, No. 2. P. 250–261.

8. Doubilet P.M., Benson C.B. Further evidence against the reliability of the human chorionic gonadotropin discriminatory level // J. Ultrasound Med. 2011. No. 30 (12). P. 1637–1642.

9. Ишутина Т.М., Черемисин В.М., Павлова Н.Г. Возможности высокопольной МРТ и ее место в алгоритме раннего распознавания эктопической беременности // Лучевая диагностика и терапия. 2016. № 4 (7). С. 66–70. [Ishutina T.M., Cheremisin V.M., Pavlova N.G. The possibilities of high-field MRI and its place in the algorithm of early recognition of ectopic pregnancy. Radiation diagnostics and therapy, 2016, No. 4 (7), рp. 66–70 (In Russ.)].