Placental Lakes Research Articles

Presence and Size of Placental Lakes on 20-Week Fetal Anatomy Ultrasound and Obstetrical Outcomes

Our objective was to determine if placental lake presence or size is associated with adverse pregnancy outcomes. This was a retrospective cohort of patients who had fetal anatomy ultrasounds at 18–22 weeks and delivered between 2018 and 2022. Placental lakes were classified as small (>2.0 to 3.9 cm) or large (≥4 cm). Multiple gestations, placenta previas, and placenta accretas were excluded. Outcomes included low birthweight, cesarean delivery, primary cesarean for non-reassuring fetal heart tracing, fetal growth restriction, preterm birth, and severe preeclampsia. A total of 1052 patients were included; 294 had placental lakes (204 small, 90 large). No differences in pregnancy outcomes were observed.

EP18.49: Ultrasound assessment of placental lakes and calcifications and their intra‐ and interobserver agreement

EP18.49: Ultrasound assessment of placental lakes and calcifications and their intra‐ and interobserver agreement

Placental and Doppler ultrasound findings in pregnant women with SARS-CoV-2 infection

Several viral infections cause changes in the placenta. Cytomegalovirus, herpes viruses, and HIV cause increased placental thickness; Zika virus induces focal regions of necrosis; parvovirus B19 causes a structural injury. Umbilical flow can be considered a direct measurement of vascular placental function. This study aimed to compare placental ultrasound and umbilical Doppler findings in pregnant women who tested positive or negative for SARS-CoV-2. Our work aimed to confirm the suspicion of placental infection and the consequence in fetal physiopathology. Fifty-seven pregnant women who tested positive for SARS-CoV-2 at the time of or 1 month before the ultrasound scan were evaluated. Cases included 9 first trimester, 16 second trimester, and 32 third trimester ultrasound scans. For comparison, 110 pregnant women (controls) were evaluated. They included 19 women in their first trimester, 43 in their second trimester, and 48 in the third trimester. Controls were asymptomatic and tested negative for SARS-CoV-2 infection in the last 72 hours before the ultrasound scan. Fetal biometry, placental thickness, placental lakes and Doppler umbilical vein parameters, including venous cross-sectional area (mean transverse diameter and radius of umbilical vein, mean velocity of umbilical vein), and umbilical vein blood flow were evaluated. Placental thickness (in millimeter) was significantly higher in the group of pregnant women with SARS-CoV-2 infection (53.82 [10-115]) than in the control group (33.82 [12-66]; P<.001) in their second and third trimesters. The frequency of >4 placental lakes was significantly higher in the group of pregnant women with SARS-CoV-2 infection (28/57 [50.91%]) than in the control (7/110 [6.36]; P<.001) in all 3 trimesters. The mean velocity of umbilical vein was significantly higher in the group of pregnant women with SARS-CoV-2 infection (12.45 [5.73-21]) than in the control group (10.81 [6.31-18.80]; P=.001) in all 3 trimesters. Umbilical vein blood flow (in milliliter per minute) was significantly higher in the group of pregnant women with SARS-CoV-2 infection (389.9 [6.52-1496.1]) than in the control group (305.05 [3.11-1441]; P=.05) in all 3 trimesters. Significant differences in placental and venous Doppler ultrasound were documented. Placental thickness, placental venous lakes, mean velocity of umbilical vein, and umbilical vein flow were significantly higher in the group of pregnant women with SARS-CoV-2 infection in all 3 trimesters.

Clinical correlation between volume of placental lakes and non-reassuring fetal status: a retrospective cohort study.

This study evaluated the correlation between placental lakes and non-reassuring fetal status. We analyzed data from pregnant women who underwent fetal echocardiography at the Fujian Maternity and Child Health Hospital. Women with singleton pregnancies at a gestational age of 20-24 weeks were included. Sociodemographic and clinical data were collected. Pregnant women with (case group) and without (control group) placental lakes were screened, and their placental Doppler ultrasound data and pregnancy outcome were recorded. Univariate and multivariable analyses were done to evaluate the correlation between the volume of placental lakes and the non-reassuring fetal status. A total of 1,728 pregnant women (156 with placental lakes) were included in this study. There were no significant differences in age of delivery and BMI between the pregnant women with placental lakes and the control group. The non-reassuring fetal status rate in the case group was higher than that in the control population, without statistical significance (5.8% vs. 3.5%, p=0.226). Subgroup analysis showed that a higher volume of placental lakes was positively associated with non-reassuring fetal status risk, with an odds ratio (OR) (95% CI) of 1.90 (1.29-2.66) (p for trend < 0.001). This positive correlation persisted even after adjustment for confounding factors. Taken together, our analyses demonstrated a graded increase in the non-reassuring fetal status rate with increased volume of placental lakes. Thus, robust clinical monitoring of placental lakes would help in timely detection of non-reassuring fetal status.

Size and Number of Placental Lakes on 20-Week Anatomy Ultrasound and Obstetric Outcomes [A190

INTRODUCTION: Placental lakes are vascular spaces within the placenta filled with maternal blood which appear hypoechoic on ultrasound. They are frequently dismissed as a benign finding despite limited data. The objective of this study was to determine whether large lakes or multiple lakes are associated with an increased risk of adverse pregnancy outcomes. METHODS: Retrospective cohort of all pregnant women with placental lakes on 20-week fetal anatomy ultrasound from January 2018 to July 2021 who delivered at one of seven hospitals in a large health system. Exclusion criteria were multiple gestations, placenta previa, and invasive placentation. For each patient, clinical characteristics were obtained and ultrasound images were reviewed to determine whether multiple lakes were present and to measure the lake with the longest dimension. Patients with small placental lakes (&lt;5 cm) were compared to those with large placental lakes (≥5 cm). The outcomes of interest were preterm birth, low birth weight, mode of delivery, and preeclampsia. Institutional review board approval was obtained. RESULTS: A total of 210 patients were included for analysis: 23 (11%) had large placental lakes and 187 (89%) had small placental lakes. The mean largest dimensions were 6.3 cm and 3.0 cm in each group, respectively. Multiple lakes were observed in 163 cases (78%). No demographic differences were noted between groups. There was no difference in gestational age at delivery, preterm birth, cesarean delivery, preeclampsia, or birth weight between groups. CONCLUSION: Placental lakes identified on 20-week fetal anatomy ultrasound, even when larger than 5 cm or multiple, were not associated with adverse pregnancy outcomes.

Human TLR8 Adversely Affects Placental Development and Induces Spontaneous Pregnancy Loss in a model of Systemic Lupus Erythematosus

Abstract SLE is associated with adverse pregnancy outcomes, particularly in the presence of antiphospholipid antibodies (aPL). Pathogenic mechanisms damaging the fetal-maternal unit, however, remain poorly understood. A role for endosomal TLR8 was recently hypothesized in aPL induced placental damage. The role of TLR8 in systemic autoimmunity has remained elusive as TLR8 function differs from mouse to man. We investigated the effect of human (hu)TLR8 expression on pregnancy outcomes in Sle1 mice that develop aPL antibodies. huTLR8 transgenic(tg) Sle1 mice were generated and huTLR8 DNA copy number and mRNA expression was confirmed by qDigital- and qRT-PCR. Pregnancies were closely followed and terminal C-sections performed at signs of dystocia/prolonged labor. Pup and placental weight was assessed. Placental tissues were characterized by H&amp;E and Myeloperoxidase (MPO) staining and inflammatory cytokine expression was assessed in placental tissue. Splenic and bone marrow immune populations were analyzed using flow cytometry. Female Sle1.huTLR8tg mice developed aPL and sm/RNP autoantibodies earlier than Sle1 controls and ±50% loss of litters was observed, compared to 0% in controls. IL-6, TNFa and MPO mRNA expression was significantly increased in placentas of affected litters and negatively correlated with placental weight. Abnormal placental morphology included placental infarcts, loss of placental lakes, arterial wall thickening and increased netting neutrophils. Here we identify a new model to study adverse pregnancy complications in SLE. In the presence of both Sle1 and huTLR8, we observed early onset of aPS autoantibodies and pregnancy loss attributed to placental developmental abnormalities, infarcts and inflammation.

Early first-trimester transvaginal ultrasound is indicated in pregnancy after previous Cesarean delivery: should it be mandatory?

Early first-trimester transvaginal ultrasound is indicated in pregnancy after previous Cesarean delivery: should it be mandatory?

OP21.06: Placental examination during routine ultrasounds in a Dutch academic hospital

Besides its location relative to the internal ostium, the placenta is often neglected during a routine ultrasound scan. This is somewhat extraordinary, since placenta insufficiency leads to serious maternal and fetal complications. The aim of this study was to investigate to what extent the placenta is examined during routine ultrasounds in a Dutch academic hospital. A questionnaire with 42 closed-ended questions was sent to sonographers, gynecologists and residents of the Maastricht University Medical Centre. Participants used a scale from 1-5 (never-almost never-regularly–routinely–always), to indicate to what extend location, structure, morphology, thickness and umbilical cord insertion are assessed during routine scans. Furthermore, ultrasound images and theses were used to determine knowledge and importance attached to placental features. Descriptive statistics, univariate models and spearman's correlation coefficient were used for statistical analysis. Forty participants filled in the questionnaire. On average, placental location is routinely assessed (4.08±0.158). Furthermore, structure (2.97±0.201), placental lakes (3.25±0.208) and calcifications (2.92±0.210) are examined regularly. Nonetheless, the vast majority of participants were unable to differentiate between different types of placental lakes (91.4%) or different grades of calcification (92%). Moreover, umbilical cord insertion, morphology and thickness are poorly examined. The extent to which the placenta is examined correlates with the subjective importance attached to this examination (p=0.019) and number of weekly obstetric ultrasounds performed (p=0.03). Placental location, structure and lakes are regularly examined during routine ultrasound, while morphology, umbilical cord insertion and placental thickness are generally ignored. Furthermore, participants are unable to discriminate between different placental lakes or calcification grading. A lack of time and knowledge on clinical relevance seems to be an important feature in the poor examination of the placenta. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

154. Placental structure and vascularization in IVF/ICSI-pregnancies compared to naturally conceived pregnancies

Objectives Although pregnancy rates of artificial reproductive techniques (ART) pregnancies have been optimized, these pregnancies have a higher risk of pregnancy complications due to impaired placentation during early pregnancy and thereby affecting placental vascularization, -structure and later on fetal growth. The aim of this study is to investigate if there are placental ultrasonographic differences between ART- and naturally conceived pregnancies. Methods A cross-sectional pilot study included 35 ART- and 30 naturally conceived (NC) pregnancies at the Maastricht University Medical Centre, between October 2017 and March 2018. Inclusion criteria were singleton pregnancies (NC, IVF/ICSI), maternal age ⩾18 years and body-mass-index (BMI) Results Placental calcifications at 12 and 16 weeks of gestation showed no significant difference between the ART and NC-group. However, placental lakes at 16 weeks were more prominent in the ART-group (59.5%) compared to the NC-group (26.1% (p = 0.017). Vascularization index at the umbilical cord insertion (UCI) and in the peripheral parts of the placenta was measured. At 12 weeks, the ART-group compared to the NC-group, showed a lower VI at the UCI (0.73 ± 0.81% vs. 2.00 ± 2.46%, p = 0.156) and in the peripheral parts of the placenta (1.73 ± 3.43% vs. 4.14 ± 4.92%, p = 0.023). At 16 weeks, no significant differences were found. Conclusions Reduced early placental vascularisation in ART-compared to NC-pregnancies may reflect the underlying aetiology of impaired placentation. These results provide promising possibilities for a more extended prospective trial and using placental ultrasonography as a predictor in the future.

Sonographically abnormal placenta: an association with an increased risk poor pregnancy outcomes.

The placenta is a most interesting but unfortunately often ignored and misunderstood organ. Placental abnormalities, therefore, can be an "early warning system" for fetal problems. A complete prenatal sonographic examination of the placenta is an essential component as its abnormalities can have a direct effect on fetal or maternal outcomes, obstetrical management and future fertility. To determine whether any association exists between the finding of an increased thickness of placenta, abnormal placenta shape, placental calcification, placental lake and abnormal cord insertion site at 20-22 and 30-32 weeks gestation with an increased risk of uteroplacental complications or a poor pregnancy outcome. A real-time ultrasound was used at the time of detail scan (at 20-22 weeks gestation) and at 30-32 weeks gestation to look for placenta appearance, fetal growth and anomaly. The main outcome measures were risk of hypertension disease in pregnancy, fetal growth restriction and poor fetal outcomes such as low Apgar score and low cord pH. The majority of the participants were Malay (77.9%). Abnormal placenta found at both gestations were placental lakes and thickness, and only one case had marginal cord insertion. Approximately 6% of the cases were confirmed placenta previa. No abnormal shape or abnormal calcification found at both gestations. About 10% patient developed hypertensive disease in pregnancy, 15% of the fetus was found to have growth restriction and another 16% have low umbilical cord pH. Majority of them delivered at term (90%) and via vaginal delivery (81%). There was no significance between presence of abnormal placental lake and thickness at both gestations with the maternal and fetal outcome. Presence of abnormal placental thickness and lakes at 30-32 weeks scan associated with maternal hypertensive disease, fetal growth restriction and low umbilical cord pH, however these were not statistically significant.

Placenta Increta Complicating Persistent Cesarean Scar Ectopic Pregnancy following Failed Excision with Subsequent Preterm Cesarean Hysterectomy.

Introduction. Cesarean scar pregnancies (CSPs) are one of the rarest forms of ectopic pregnancy. Given their rarity, there is lack of consensus regarding the management and natural course of CSPs. Case. A 37-year-old G10 P3063 female with a history of two prior cesarean deliveries was diagnosed with her second CSP at 6 weeks and 5 days in her tenth pregnancy. The patient underwent vertical hysterotomy, excision of a gestational sac implanted in the cesarean sac, and bilateral salpingectomy via a laparotomy incision. The histopathology report confirmed immature chorionic villi. The patient returned 10 weeks later and was found to be still pregnant. Obstetric ultrasound confirmed a viable fetus of 19 weeks and 4 days of gestational age with a thin endometrium and an anteroposterior and right lateral placenta with multiple placental lakes. The patient ruptured her membranes at 31 weeks of gestation and pelvic MRI revealed an anterior placenta invading the myometrium and extending to the external serosal surface consistent with placenta increta. Following obstetric interventions, a live female infant was delivered by cesarean hysterectomy (because of placenta increta) at 32 weeks of gestation. Conclusion. Development of standardized guidelines for management of CSPs, as well as heightened vigilance for possible complications, is required for proper care and avoidance of potential morbidity and mortality.

Natural history of early first-trimester pregnancies implanted in Cesarean scars.

To describe the ultrasound findings and natural history of pregnancies implanted within or on Cesarean section scars in the first trimester of pregnancy. This was a prospective observational study of 10 women diagnosed with a pregnancy implanted in or on a Cesarean section scar in the first trimester, who declined medical intervention because of their desire to continue the pregnancy. The study population comprised women at < 12 weeks' gestation who were seen in our early pregnancy unit between January 2011 and September 2013. Nine women were followed up by serial ultrasound examinations and had detailed care plans for delivery at King's College Hospital (KCH). One woman was followed up and delivered at another teaching hospital. The first-trimester ultrasound findings were compared with the clinical outcome of the pregnancy. The nine patients who were followed up at KCH developed ultrasound findings of morbidly adherent placenta (MAP) in the second and third trimesters. All 10 patients were diagnosed with MAP at the time of delivery by Cesarean section. The gestational age at delivery ranged from 26 to 38 weeks. The uterus was conserved in five patients, and Cesarean hysterectomy was performed in the remaining five. All three women with complete implantation of the gestational sac within the scar and two of three cases with placental lakes in the first trimester had hysterectomies. The two cases with bulging of the gestational sac out of the uterine contour had a preterm emergency hysterectomy due to placenta percreta. Histology confirmed placenta accreta in the five hysterectomy specimens. There were no fetal or neonatal complications. Implantation of a pregnancy on or in a Cesarean section scar is a precursor of MAP; however, the degree of morbidity associated with this implantation is variable and difficult to predict based on first-trimester ultrasound findings only. The assessment of ongoing pregnancies implanted in Cesarean scars is most beneficial when performed between 7 and 9 weeks' gestation. Complete implantation within the myometrial defect, bulging of the trophoblast from the uterine contour and large placental lakes in the first trimester are ultrasound findings that may predict severe placenta accreta or percreta and consequently a poor outcome.

Three-dimensional high-definition flow in the diagnosis of placental lakes

Placental lakes are sonolucent areas often found in the normal placenta. Most of them are asymptomatic. They are sometimes related to placenta accreta or intrauterine fetal growth restriction, among other conditions. Although Doppler sonography is useful for evaluating noxious placental lakes, it is not easy to adapt Doppler studies to conventional two-dimensional color Doppler sonography because of the low-velocity blood flow and high vascularity in the placenta. Here, we demonstrate how three-dimensional high-definition imaging of flow provides a novel visual depiction of placental lakes, which helps substantially with the differential diagnosis. As far as we know, there have been no previous reports of observation of placental lakes using three-dimensional high-definition imaging of flow.

Systematic review of sonographic findings of placental mesenchymal dysplasia and subsequent pregnancy outcome

To describe the sonographic features and pregnancy outcomes of placental mesenchymal dysplasia (PMD), an entity often misdiagnosed as molar pregnancy. We reviewed PMD cases from our institution and performed a systematic review of the existing literature. Inclusion criteria for the review were diagnosis of PMD as defined by placental pathology, description of placental morphology on antenatal ultrasound and reporting of pregnancy outcomes. We found three cases of PMD at our institution. Patient 1 had elevated human chorionic gonadotropin (hCG) and an enlarged, hydropic placenta at 13 weeks, suggestive of a molar pregnancy. Patient 2 also had elevated hCG with large, vascular placental lakes on ultrasound suggesting placenta accreta or molar pregnancy. Case 3 involved placentomegaly and fetal anomalies suggestive of Beckwith-Wiedemann syndrome. From the literature review, 61 cases met the inclusion criteria. The most common sonographic features included enlarged (50%) and cystic (80%) placenta with dilated chorionic vessels. Biochemical aneuploidy screening abnormalities were relatively common as were fetal anomalies, Beckwith-Wiedemann syndrome and other genetic abnormalities. Pregnancy complications included intrauterine growth restriction (IUGR; 33%), intrauterine fetal death (IUFD; 13%), and preterm labor (33%). Pregnancies without fetal anomalies, IUGR, IUFD or preterm labor had normal neonatal outcomes despite PMD (9%). The differential diagnosis of PMD includes molar pregnancy and other placental vascular anomalies. PMD is associated with adverse pregnancy outcome, so heightened surveillance with genetic evaluation, serial growth scans and third-trimester assessment of wellbeing should be considered. PMD must be differentiated from gestational trophoblastic disease because management and outcomes differ.

P31.11: Complete hydatidiform mole and normal live birth: placental mosaicism or twin with CHM?

Introduction: survival of a normal fetus to term in the presence of hydatidiform mole remains an extremely uncommon occurrence. Prenatal diagnosis is possible by ultrasonography showing molar invasion of the normal placenta without clear margin. Antenatal detection of mole co existing with a viable fetus should warrant genetic analysis and search for gross malformation of the fetus. Case report: we report a rare case exhibiting molar pregnancy and a coexisting normal fetus. A 29 year, primigravida had an episode of vaginal bleeding at 18 weeks which suggested avascular lower placenta with multiple cystic area measuring 12 × 5 × 9 cm with normal fetus. She had two weekly growth scan and Doppler as diagnosis was not clear. It was thought to be multiple placental lakes. Growth and Doppler remains normal and had term SVD. Placenta was sent for histopathology which suggested normal placenta with an area of complete hydatidiform mole. It was difficult to differentiate from mosaic CHM, twin with normal co-twin and CHM. Discussion: coexistent live fetus and molar placenta has never been reported. Complications including pre-eclampsia, hyperthyroidism, vaginal bleeding, persistent gestational trophoblastic disease, preterm labour, miscarriage and anaemia increases. Several factors may influence the outcome in partial mole such as karyotype of the fetus, size of the molar placenta, the speed of molar degeneration and fetal anaemia.

Fetal growth restriction and reversed middle cerebral artery end‐diastolic flow with subchorionic placental lake

Fetal growth restriction (FGR) is frequently associated with uteroplacental insufficiency. Placental lakes are avillous spaces filled with maternal venous blood that usually do not compromise the pregnancy outcome; however, a few reports describe FGR in association with placental lakes. Reversed middle cerebral artery (MCA) end-diastolic flow is a rare event and a potential indicator of poor fetal outcome due to placental insufficiency. We report a case of severe FGR associated with a huge subchorionic placental lake concomitant with reversed MCA end-diastolic flow. We also conducted a literature review.

Developmental changes in spiral artery blood flow in the human placenta observed with colour Doppler ultrasonography

ObjectivesOur current knowledge of the physiological dilatation of spiral arteries in pregnancy, is based on histology. Real-time ultrasound visualisation of these changes may aid understanding of abnormal placentation. This study aimed to investigate if changes in the spiral artery blood flow can be followed ‘in vivo’ and explore the novel phenomenon of the larger ‘mega-jets’. MethodsColour Doppler ultrasonography was used to identify the most prominent jets at blood from the spiral artery into the intervillous space. Their velocity, width and length were recorded seven set time points during pregnancy. ResultsFifty two uncomplicated, term normotensive pregnancies were studied. Width and length of the jets' Doppler signals increased with gestation, the velocity decreased. The length of the jets shows a bi-modal frequency distribution. The width of the signals of longer (‘mega’) jets was significantly greater (p = 0.001) than that of the jets (mean 4.3 mm (3.1–5.9) versus 3.8 mm (1.8–5.8) respectively) at 34 weeks. However, there was no significant difference in the peak systolic velocity (p = 0.2). ConclusionThis study confirms that ultrasound can be used to study the gestation dependent changes in the haemodynamics of the placental basal plate predicted, but not proven, by histologic data. The bi-modal distribution of jet lengths suggests that mega-jets are a separate entity to ‘normal’ jets. That they are significantly wider than ‘normal’ jets and yet maintain the same velocity of blood flow suggests that they have a greater volume of blood flow. The mechanism for this is hypothesised and their apparent relationship with simple placental lakes discussed.

The clinical significance of large placental lakes

The aim of our study was to establish whether there is a correlation between the size of placental lakes and adverse pregnancy outcome. Target ultrasonography for diagnosis of placental lake was performed in the 2nd trimester of pregnancy and followed up in the 3rd trimester. Placental lakes were defined as homogenous sonolucent avillous lesions greater than 2 cm × 2 cm in diameter. The 109 pregnant women enrolled in this study were divided into four groups according to the size and change in size of placental lakes. Clinical characteristics and pregnancy outcomes in each group were compared. Some placental lakes decreased and disappeared, whereas others persisted. There were no significant differences in clinical characteristics among the four investigated groups. Fetal small-for-gestational-age status was significantly correlated with large placental lakes, compared to small. Large placental lakes were correlated with the fetal status of small for gestational age. Therefore, if a large placental lake is identified in the 2nd trimester of pregnancy, appropriate surveillance should be considered for the remainder of the pregnancy.

The impact of ultrasonographic placental architecture on antenatal course, labor and delivery in a low-risk primigravid population

Objective. To ascertain the impact of placental architecture on antenatal course and labor delivery in a low-risk primigravid population.Methods. This study involves prospective recruitment of 1011 low-risk primigravids with placental ultrasound at 22–24 weeks and 36 weeks. Detailed postnatal review of all mothers and infants was undertaken. Retrospective analysis of ultrasound and clinical outcome data was performed.Results. Eight hundred ten women with complete outcome data were available. Anterior placentation was statistically associated with intrauterine growth restriction (IUGR) and preterm birth and fundal placentation was significantly associated with a higher incidence of pregnancy-induced hypertension and infants with a birthweight less than the 9th centile. Placental infarcts in the third trimester was significantly increased in cases complicated by pre-eclampsia (PET) and in cases with fetal acidosis. Placental calcification was associated a 40-fold increase in the incidence of IUGR. Placental lakes in the second trimester were more prevalent in patients with threatened miscarriage. Increased placental thickness was associated with a higher rate of fetal acidosis. The Grannum grade of the placenta was higher with threatened first or second trimester loss, PET and in infants born less than 9th centile for gestation.Conclusion. Placental site and architecture impact on the incidence of maternal and fetal disease.

A case of a huge placental lake; prenatal differential diagnosis and clinical management

Placental lakes are sonolucent or hypoechoic areas in images of the placenta, usually considered a physiological dilation of intervillous space with a rather good obstetrical outcome. However, diagnostic criteria for and the clinical significance of placental lakes are yet to be completely established, because of a wide variety of ultrasound findings, especially on color Doppler examination. We experienced a case of a huge placental lake, larger than the total placental area, located in an entire retroplacental space, concomitant with several penetrations of artery type blood flow. The antenatal differential diagnosis and course of clinical management are reported.