A prospective study on placental migration in mid trimester low lying placenta
DOI:
https://doi.org/10.18203/2320-1770.ijrcog20222799Keywords:
Low lying placenta, Migration, Placenta previaAbstract
Background: Objectives of the study were: to assess migration of low-lying placenta diagnosed by ultrasound around 20 weeks of gestation and to evaluate the factors influencing placental migration as well as to reduce feto-maternal morbidity and or mortality by excluding placenta previa and placenta accreta early.
Methods: All antenatal mothers undergoing routine transabdominal congenital anomaly scan around 20 weeks of gestation were subjected to transvaginal ultrasonography to confirm low lying placenta. Every 4 weekly transvaginal ultrasonography was repeated until the lower edge of placenta migrated beyond 3 cm of internal cervical os or the patient had delivered, which one was earlier.
Results: Out of total 686 cases, only 56 (8.16%) mothers had low-lying placenta in mid trimester. Follow up of these 56 cases showed that 33 (58.93%) cases placenta had migrated at term and 23 (3.35%) cases persist as placenta previa. The rate of migration of placenta was 80.76%, 39.13% and 42.86% in mothers following previous vaginal delivery, caesarean section or prior history of MTP/suction and evacuation. Placental migration was 80% and 47.39% where the distance between the internal cervical os and lower edge of placenta was between 2.1-3 cm and between 1.5-2 cm respectively. No placental migration was noted where the initial distance was less than 1.5 cm. Placental migration was more common in anteriorly situated placenta (65.85%) than the posterior one (40%).
Conclusions: The rate of placental migration at term was 58.93%. However, factors like previous caesarean section, previous history of MTP or suction and evacuation, posteriorly situated placenta and placenta lying 1.5 cm from the internal cervical os may interfere with placental migration.
References
Leerentveld RA, Gilberts EC, Arnold MJ, Wladimiroff JW. Accuracy and safety of transvaginal ultrasonographic placental localization. Obstet Gynecol. 1990;76:759-62.
Farine D, Fox HE, Jakobson S. Vaginal sonography for diagnosis of placenta praevia. Am J Obstet Gynecol. 1988;159:566-9.
Ancona S, Chatterjee M, Rhee I. The midtrimester placenta previa: a prospective follow up. Eur J Radiol. 1990;10:215-6.
Oppenheimer L, Holmes P, Simpson N, Dabrowski A. Diagnosis of low lying placenta: can migration in the third trimester predict outcome? Ultrasound Obstet Gynecol. 2001;18:100-2.
Chama CM, Wanonyil K, Usman JD. From low- lying implantation to placenta praevia: a longitudinal ultrasonic assessment. J Obstet Gynaecol. 2004;24(5):516-8.
Leuria MR, Smith RS, Treadwell MC, Comstock CH, Kirk JS, LeeW, et al. The use of second- trimester transvaginal sonography to predict placenta praevia. Ultrasound Obstet Gynecol. 1996;8:337-40.
Shravage Joystna C, Dhumale Hema A, Bellad MB. Assessment of placental migration in mid trimester low lying placenta. J Obstet Gynecol India. 2009;59(4):317-9.
Taipale P, Hiilesmaa V, Ylostalo P. Diagnosis of placenta previa by transvaginal sonographic screening at 12-16 weeks in a nonselected population. Obstet Gynecol. 1997;89:364-7.
Ananth CV, Smulian JC, Vintzileos AM. The association of placenta previa with history of caesarean delivery and abortion: a meta analysis. Am J Obstet Gynecol. 1997;177:1071-8.
Oppenheimer SL. SOGC Clinical Practice guideline No. 189. 2007. Available at: https://www.jogc.com/article/S1701-2163(16)32401-X/pdf. Accessed on 24 June 2022.
Sowjanya Kumari J, Bhavani V, Swetha, Himabindu, Madhumitha.M. Placental Migration in Mid Trimester Low Lying Placenta. IOSR- JDMS. 2016;15:150-6.
Lea T, Josip D, Marcela I. Obstetric Risk Factors Associated with Placenta Previa Development: Case-Control Study. Crot Med J. 2003;44(6):728-33.
Ghourab S, AI- Jabari A. Placental migration and mode of delivery in placenta previa: transvaginal sonographic assessment during the third trimester. Ann Saudi Med. 2000;20:382-5.
Newton ER, Brass V, Cetrulo CL. The epidemiology and clinical history of asymptomatic mid- trimester placenta previa. Am J Obstet Gynecol. 1994;342:130-4.
David M, Martin S, Helen T. Low– Lying placenta. Radiology. 1982;144:577-80.
