Available online on 15.02.2025 at http://jddtonline.info

Journal of Drug Delivery and Therapeutics

Open Access to Pharmaceutical and Medical Research

Copyright  © 2025 The  Author(s): This is an open-access article distributed under the terms of the CC BY-NC 4.0 which permits unrestricted use, distribution, and reproduction in any medium for non-commercial use provided the original author and source are credited

Open Access Full Text Article   Research Article

Investigation of Placentas of Preeclamptic Patients with Very Premature Membrane Rupture

Serhat Ege ¹, Murat Akkuş ¹, Fırat Aşır ¹*, Medine Arslan Alcan ² 

¹ Department of Histology and Embryology, Medical Faculty, Dicle University, Diyarbakır, Turkey

² Department of Gynecology and Obstetrics, Medical Faculty, Dicle University, Diyarbakır, Turkey

 

 

INTRODUCTION

Preeclampsia (PE) is one of the most common pregnancy complications leading to maternal and fetal mortality and morbidity worldwide. It is considered the second most common major cause of abnormal pregnancy outcomes ¹. PE is most commonly seen after the 20th week of pregnancy with high blood pressure (140/90 mmHg) and proteinuria (albumin >300 mg per 24 hours) ². The prevalence of PE has been reported to be 2–8% of all pregnancies in various countries of the world, even among different ethnic groups living in the same country ³. Important risk factors for PE include previous history of hypertension, autoimmune system, kidney disease, high blood sugar level, maternal weight, age of the pregnant women, ethnicity and family history ⁴.

Premature membrane rupture (PROM) is the rupture of the membranes one hour before the onset of uterine contractions, regardless of gestational age. According to gestational age, PROM can be divided into two categories: term PROM after 37 weeks of gestation and preterm PROM (pPROM) before 37 weeks of gestation. PROM is one of the common obstetric complications, but its accurate incidence is difficult to estimate due to the wide variation reported in the current literature. Recent data suggest that it complicates approximately 3–10% of all pregnancies ⁵. PROM is a potential risk factor for both maternal and infant mortality and morbidity. Neonatal complications associated with PROM include prematurity, trauma, fetal distress, intraventricular hemorrhage, respiratory distress syndrome, and intrauterine infection. These complications ultimately lead to poor fetal development during pregnancy ⁶.

Our aim in this study was to examine histopathological changes in the placentas of preeclamptic patients diagnosed with PROM.

MATERIALS AND METHODS 

Obtaining Placentas

Our study was initiated with the approval of the Ethics Committee of Dicle University Faculty of Medicine dated 17.05.2023 and numbered 186. In our study, placentas were obtained by obtaining informed consent forms from a total of 90 pregnant patients (regardless of age), 45 controls and 45 PROM+Preeclampsia pregnant patients. A postpartum consent form was obtained from the mothers who applied to the Gynecology and Obstetrics Clinic of Dicle University Faculty of Medicine Hospital. After the placentas were washed with physiological serum, they were placed in 10% buffered neutral formalin under appropriate conditions in the operating room for tissue follow-up and taken to the Dicle University Faculty of Medicine Histology and Embryology Department Laboratory.

Tissue Tracking for Light Microscopic Examination

Placentas taken to the Dicle University Medical Faculty Histology and Embryology Department laboratory were taken from both the central maternal and central fetal sides of the placenta for tissue tracking, and then placed in buffered 10% neutral formalin in numbered transparent glass sample bottles. Tissue pieces taken from the central maternal and fetal sides were kept in transparent glass sample bottles for 16 hours for fixation. After the fixation stage, the tissue pieces were kept under running tap water for 12 hours to remove formalin solution. Then, the tissue pieces were kept in 50%, 70%, 80%, 90% and 96% alcohols for a total of 8 hours and finally, they were kept in absolute alcohol (99.9%) for 2x20 minutes to complete the dehydration process. The tissues were kept in xylene for 2x15 minutes to remove alcohol and the transparency process was performed. After waiting in paraffin for 2x1 hours in an oven set at 58oC for infiltration, tissue pieces were embedded in paraffin blocks for blocking ¹². After the embedding process, 5𝜇m thick sections were taken from each paraffin block with the help of a fully automatic rotary microtome (Leice RM2265, Germany). Hematoxylin-Eosin (H-E) staining were applied to the obtained sections. Preparations were examined under a light microscope using the Zeiss Imager A2 light and Zen 3.00 software program.

RESULTS 

Hematoxylin-Eosin Findings of Control group

In the control group, placental structures were observed as normal. Chorionic villi exhibited an oval and regular structure, while syncytiotrophoblasts were found in the outer part and cytotrophoblasts in the inner part. Syncytial nodes were few in number and fibrin accumulation was limited. Endothelial cells in villous capillaries were long and thin, fibers were regular in the root villous connective tissue, and stromal cells were properly placed. No bleeding or lymphocyte infiltration was observed in the intervillous area (Figure 1 and Figure 2).

 

 

Figure 1: Placental section of the Control Group. Arrow: villus, star: intervillous area, Hematoxylin Eosin Staining, Bar: 10 µm, Magnification: 10X

Figure 2: Close-up placental section of the Control Group. Arrow: villus, arrowhead: syncytial node, star: intervillous area, fb: fibrin, bd: connective tissue, asterisk: capillary, Hematoxylin Eosin Staining, Bar: 50 µm, Magnification: 20X

 

Hematoxylin-Eosin Findings of PROM+Preeclampsia group

In the PROM+preeclampsia group, degeneration in the villi, pyknosis and apoptosis in the trophoblastic layer cells were observed. Vascular dilatation and congestion were detected in the villi, while hyperplasia was observed in the endothelial cells. There was intense hemorrhage and immune cell accumulation in the intervillous area. While fibrin accumulation increased, numerous Hoffbauer cells were detected in the villous stroma. Decidual cell degeneration was clearly observed in areas close to the maternal plate (Figure 3 and Figure 4).

 

 

Figure 3: Placental section of PROM+preeclampsia group. Arrow: villus, fb: fibrin, asterisk: capillary, bd: connective tissue, Hematoxylin Eosin Staining, Bar: 10 µm, Magnification: 10X

Figure 4: Close-up placental section of the PROM+preeclampsia group. Arrow: villus, arrowhead: syncytial node, star: intervillous area, fb: fibrin, bd: connective tissue, asterisk: capillary, Hematoxylin Eosin Staining, Bar: 50 µm, Magnification: 20X

 

 

DISCUSSION 

Our study is the first to analyze histopathological changes in PE patients with PROM. In placenta studies, disruption of the controlled inflammatory response caused increased damage at the vascular and cellular levels.

Preeclampsia is a systemic disease that occurs in the second half of pregnancy, is characterized by hypertension and proteinuria, and can lead to serious complications for both the mother and the fetus. Although the etiopathogenesis of preeclampsia has not been fully explained, it is known that placental insufficiency and endothelial dysfunction are among the basic mechanisms of the disease. Histopathological findings show how these mechanisms affect the placental structure throughout pregnancy ^7-11

Histopathological changes commonly seen in preeclamptic placentas include placental ischemia, villous degeneration, limited trophoblast invasion, and fibrinoid necrosis. In normal pregnancy, as a result of the invasion of spiral arteries by trophoblasts, the vessel walls expand, forming a low-resistance system that supports uteroplacental circulation. However, in preeclampsia, this invasion is insufficient and the spiral arteries remain narrow and muscular. This reduces uteroplacental perfusion, causing hypoxia and oxidative stress. Oxidative stress triggers placental inflammation, leading to endothelial dysfunction and systemic inflammatory response ^12-14.

Histopathologically, significant fibrin deposition, intense inflammatory cell infiltration, increased Hoffbauer cells, and disruptions in chorionic villus structure are reported in preeclamptic placentas. In addition, findings such as increased apoptosis in trophoblastic cells, stromal edema, villous fibrosis, and perivascular degeneration are also common. In addition to endothelial cell hyperplasia and vascular dilatation, microthromboses are frequently observed in preeclampsia cases. These findings support the vascular dysfunction and inflammatory processes underlying preeclampsia ^15,16.

The histopathological effects of preeclampsia can lead to complications such as fetal growth retardation (FGR) and intrauterine hypoxia due to placental insufficiency. Therefore, a better understanding of placental changes associated with preeclampsia is important for the development of early diagnosis and treatment strategies for the disease. Future studies may contribute to our better understanding of the pathophysiology of preeclampsia by examining the immunological and molecular mechanisms in more detail ^17,18.

In our study, placental histopathological changes observed in the PROM+preeclampsia group indicate that the placental structure may be seriously affected. The disruption of the controlled inflammatory response caused increased damage at the vascular and cellular levels. In terms of clinical significance, our findings underline the inflammatory and vascular processes in the placental microenvironment in pregnancies complicated by preeclampsia.

Acknowledgement: This study was a part of doctoral thesis of Serhat Ege, from Department of Histology and Embryology, Dicle University

Conflict of Interest: The authors have no conflicts of interest regarding this investigation.

Author Contributions: All authors have equal contribution in the preparation of manuscript and compilation.

Source of Support: Nil

Funding: The authors declared that this study has received no financial support.

Informed Consent Statement: All patients agreed to participate the study volunteerily. 

Data Availability Statement: The data presented in this study are available on request from the corresponding author. 

Ethical approval: This study was initiated with the approval of the Ethics Committee of Dicle University Faculty of Medicine dated 17.05.2023 and numbered 186.

REFERENCES 

1. Jung A, Challoumas D, Pagels L, Armijo-Olivo S, Braun T, Luedtke K. Guidelines for the development and validation of patient-reported outcome measures: a scoping review. BMJ Evid Based Med. 2024 Nov 22;29(6):363-373. https://doi.org/10.1136/bmjebm-2023-112681 PMid:38782559

2. Sibai B, Dekker G, Kupferminc M. Pre-eclampsia. Lancet. 2005;365:785-99. https://doi.org/10.1016/S0140-6736(05)17987-2 PMid:15733721

3. Gokalp-Ozkorkmaz E, Asir F, Basaran SO, Agacayak E, Sahin F, Kaya S, Erdogan G, Deveci E. Examination of Bcl-2 and Bax Protein Levels for Determining the Apoptotic Changes in Placentas with Gestational Diabetes and Preeclampsia. Proceedings. 2018; 2(25):1548. https://doi.org/10.3390/proceedings2251548

4. Sutapa A, Gagandeep KW. Prevalence and risk factors for symptoms suggestive of pre-eclampsia in Indian women. J Womens Health. 2014;3:1-9.

5. Jung A, Challoumas D, Pagels L, Armijo-Olivo S, Braun T, Luedtke K. Guidelines for the development and validation of patient-reported outcome measures: a scoping review. BMJ Evid Based Med. 2024 Nov 22;29(6):363-373 https://doi.org/10.1136/bmjebm-2023-112681 PMid:38782559

6. Duley L. The global impact of pre-eclampsia and eclampsia. Semin Perinatol. 2009;33:130-7. https://doi.org/10.1053/j.semperi.2009.02.010 PMid:19464502

7. Aşır F, Oğlak SC, Ağaçayak E, Alabalık U. Homeobox A Cluster 7 (HOXA7) protein expression increased in the placentas of patients with preterm delivery. Perinatal Journal 2023;31(3):213-218

8. Mostello D, Catlin TK, Roman L, Holcomb WL, Jr, Leet T. Preeclampsia in the parous woman- who is at risk. Am J Obstet Gynecol. 2002;187:425-9. https://doi.org/10.1067/mob.2002.123608 PMid:12193937

9. Gandhi M, Shah F, Panchal C. Obstetric outcomes in premature rupture of the membrane. Int J Gynecol Obstet. 2012;16:1-5. https://doi.org/10.5580/2ed6

10. Aydeniz Acar, G. E., Sevinç Akdeniz, A., Türe, Z., Aşır, A., Acar, M., Aşır, F., ... KORAK, T.(2024). HOXA1 expression in placentas of woman with fetal growth restriction. Perinatal Journal , vol.32, no.2, 166-172.

11. Fox R, Kitt J, Leeson P, Aye CYL, Lewandowski AJ. Preeclampsia: Risk Factors, Diagnosis, Management, and the Cardiovascular Impact on the Offspring. J Clin Med. 2019 Oct 4;8(10):1625. https://doi.org/10.3390/jcm8101625 PMid:31590294 PMCid:PMC6832549

12. Ali M, Ahmed M, Memon M, Chandio F, Shaikh Q, Parveen A, Phull AR. Preeclampsia: A comprehensive review. Clin Chim Acta. 2024 Sep 15;563:119922. https://doi.org/10.1016/j.cca.2024.119922 PMid:39142550

13. Ives CW, Sinkey R, Rajapreyar I, Tita ATN, Oparil S. Preeclampsia-Pathophysiology and Clinical Presentations: JACC State-of-the-Art Review. J Am Coll Cardiol. 2020 Oct 6;76(14):1690-1702. https://doi.org/10.1016/j.jacc.2020.08.014 PMid:33004135

14. Dimitriadis E, Rolnik DL, Zhou W, Estrada-Gutierrez G, Koga K, Francisco RPV, Whitehead C, Hyett J, da Silva Costa F, Nicolaides K, Menkhorst E. Pre-eclampsia. Nat Rev Dis Primers. 2023 Feb 16;9(1):8. https://doi.org/10.1038/s41572-023-00417-6 PMid:36797292

15. Gelkopf M, Mazor Y, Roe D. A systematic review of patient-reported outcome measurement (PROM) and provider assessment in mental health: goals, implementation, setting, measurement characteristics and barriers. Int J Qual Health Care. 2021 Mar 5;34(Suppl 1):ii13-ii27. doi: 10.1093/intqhc/mzz133. Erratum in: Int J Qual Health Care. 2022 Mar 28;34(Suppl 1):ii112. https://doi.org/10.1093/intqhc/mzz133 PMid:32159763

16. Fuat Zaman, Fırat Aşır, Işılay Sezen Ermiş, Mehmet Cudi Tuncer, Engin Deveci, Süleyman Cemil Oğlak. Immunohistochemical Analysis of Vimentin and Zonula Occludens-1 in Placentas of Patients with PPROM. Clin. Exp. Obstet. Gynecol. 2024, 51(1), 18. https://doi.org/10.31083/j.ceog5101018

17. Sokas C, Hu F, Edelen M, Sisodia R, Pusic A, Cooper Z. A Review of PROM Implementation in Surgical Practice. Ann Surg. 2022 Jan 1;275(1):85-90. https://doi.org/10.1097/SLA.0000000000005029 PMid:34183512

18. Churruca K, Pomare C, Ellis LA, Long JC, Henderson SB, Murphy LED, Leahy CJ, Braithwaite J. Patient-reported outcome measures (PROMs): A review of generic and condition-specific measures and a discussion of trends and issues. Health Expect. 2021 Aug;24(4):1015-1024. https://doi.org/10.1111/hex.13254 PMid:33949755 PMCid:PMC8369118