Point-Counterpoint: Placental examination

Yes. Adopting the guidelines at the institutional level will maximize care.

Vlad D. Ianus, MD, MPH, and Sharon T. Phelan, MD

Dr. Ianus is Assistant Professor of Pediatrics
, Division of Neonatology, 
University of New Mexico Children's Hospital, 
Albuquerque.

Dr. Phelan is Professor, Department of Obstetrics and Gynecology, University of New Mexico, Albuquerque.

Neither author has a conflict of interest to disclose with respect to the content of this article.

The placenta, which plays a central role during gestation, can offer important information regarding a pregnancy, several perinatal conditions, the well-being of the neonate, and the prognosis of future pregnancies. Obstetric morbidities and changes in the uterine environment are often reflected in the placental examination findings. Some of these findings (eg, chorioamnionitis) correlate highly with long-term developmental outcomes of the infant that may not be accurately predicted by a clinical diagnosis alone.

Placental examination reveals abnormal findings in almost all cases of fetal death, and the pathology report can diagnose the cause of death in about one-third of the cases in which it could not be determined clinically. Lastly, data resulting from a placental examination may offer essential evidence in medical liability cases.

Issued in 1997 by the College of American Pathologists (CAP), a Practice Guideline for Examination of the Placenta (PGEP) remains one of the most comprehensive and current recommendations regarding the topic.¹

Yet studies that investigated adherence to the PGEP revealed that fewer than half the placentas that met criteria were sent to pathology.^2-5 Several explanations for this are possible, but improved adherence to the guidelines can be achieved by refrigerating placentas for several days before discarding them. That allows both the obstetrical and pediatric practitioners the chance to request in-depth examination of a placenta based on clinical information that might have been unavailable or overlooked at the time of delivery or based on changes in neonatal circumstances that develop early in postnatal life.⁶

A pathology request that provides essential information to the pathologist will likely improve the resulting reports. A template that lists the complications that prompt a placental review allows the obstetric provider to simply circle the indication for the request. These should include maternal complications, fetal complications, and placental findings, as well as basic information on the mother and gestational age at delivery. This also reinforces the indications for pathology review to the obstetrical provider.

In brief, establishment of institution-based guidelines for triage of placental tissues that include initial submission for pathology and short-term storage in cases not initially felt to meet criteria is necessary to help clinicians utilize the valuable information the placentas may yield. Increased utilization of placental evaluation will maximize our care for obstetric patients and their newborns.

References

1. Langston C, Kaplan C, Macpherson T, et al. Practice guideline for examination of the placenta: developed by the Placental Pathology Practice Guideline Development Task Force of the College of American Pathologists. Arch Pathol Lab Med. 1997;121(5):449–476.

2. Badawi N, Kurinczuk JJ, Keogh JM, Chambers HM, Stanley FJ. Why is the placenta being ignored? Aust N Z J Obstet Gynaecol. 2000;40(3):343–346.

3. Spencer MK, Khong TY. Conformity to guidelines for pathologic examination of the placenta. Arch Pathol Lab Med. 2003;127(2):205–207.

4. Curtin WM, Krauss S, Metlay LA, Katzman PJ. Pathologic examination of the placenta and observed practice. Obstet Gynecol. 2007;109(1):35–41.

5. Booth VJ, Nelson KB, Dambrosia JM, Grether JK. What factors influence whether placentas are submitted for pathologic examination? Am J Obstet Gynecol. 1997;176(3):567–571.

6. Redline, RW. Placental pathology: Is it time to get serious? Contemporary OB/GYN. 2014;59(2):41–48.

NEXT: No. The absence of trained placental pathologists hinders accurate examination. >>

No. Absence of trained placental pathologists hinders accurate examination.

Robert J. Carpenter, Jr, MD, JD, and Edwina J. Popek, DO

Dr. Carpenter is Associate Professor, Baylor College of Medicine Department of Obstetrics and Gynecology, and Department of Molecular & Human Genetics, Center for Medical Ethics and Health Policy, Houston, Texas.

Dr. Popek is Professor of Pathology, Baylor College of Medicine, and Director of Laboratories, Texas Children's Hospital Pavilion for Women, Houston.

Neither author has a conflict of interest to disclose with respect to the content of this article.

Should all placentas be saved and undergo pathological study? Dr. Raymond Redline recently thoroughly covered this topic in these pages (Placental pathology: Is it time to get serious? Contemporary OB/GYN. 2014;59(2):41–48). This excellent article covered both the “pro” and “con” positions. Here, we will give the clinician’s response.

I (Dr. Carpenter) have worked as clinician, educator, and medico-legal reviewer for the last 35 years, and the subject of the placenta has arisen often. The information acquired from an appropriate study can often help a family who has experienced a term intrauterine fetal demise (IUFD) from an ascending infection that was not clinically recognized, or who has had an early preterm loss from placental floor infarction. In addition, I have seen many legal cases turn on the findings of the placental pathology that actually existed (and not the pathology as originally written in the clinical pathology report).

If the US healthcare system had all the funds in the world and all placentas could be examined, the major issues would revolve around timely submission of the placenta, appropriate submission of clinical data, and most importantly, gross and microscopic evaluation of placental material by an experienced and knowledgeable pathologist.

Not all placentas should be examined immediately. Many pregnancies are normal and evaluation of the placenta is unnecessary. The waste of both time and money that could be applied elsewhere means that the hypothesis that all placentas should be saved and examined should be rejected.

The College of American Pathologists 1997 Guidelines as briefly summarized by Dr. Redline do yield useful categories of clinical states, both maternal and fetal/neonatal, that warrant submission of the placenta.

I have been fortunate over the past 35 years to have at least 2 superb placental pathologists whom I have relied on and trusted. The data acquired in our institution are excellent. In the hospitals in which I have practiced over the past 10 a policy of placental storage for 7 days is in place. If an acute neonatal problem presents, and the placenta was not previously submitted to pathology, the placenta is acquired from its refrigerator storage area and submitted for examination. It is rare in that time for a significant acute neonatal/fetal problem not to be appropriately evaluated by placental examination with correlation of relevant histopathologic placental data.

However, for neonates transferred from outlying hospitals to Texas Children’s NICU, fewer than 50% of placentas are recoverable for pathological examination. This delayed acquisition and evaluation of the properly stored but previously unexamined placenta brings to light a major deficit in many hospitals where placental pathology is performed: the absence of properly trained/interested placental pathologists. The tissue in both gross and histopathological examination is performed by a trained pathologist as a routine procedure. Typically, the pathologist is neither specially trained nor especially interested in the subject. In light of the potential medico-legal implications of pathological diagnosis, incorrect diagnoses often result in lawsuits that would not have occurred if the proper interpretation of the placenta had been made initially.

To properly use our limited healthcare dollars, hospitals can do the following to acquire appropriate information for placentas that require examination:

1. Acquire an appropriate number of refrigerators in the labor/delivery area and institute a 7-day hold-and-retain policy for all placentas not sent for initial examination. This policy must be made known to all medical, nursing, and delivery personnel.

2. Review with appropriate neonatal, pathology, and obstetrical staff a list of indications for which placentas should be submitted with relevant, accurate, clinical (maternal/neonatal) data.

3. Ensure that the pathology department has a skilled placental pathologist or that it refers placentas to an expert placental pathologist for review.

The institution of these basic procedures will negate the need to examine all placentas at a cost of $0.5 billion to $1.1 billion annually. At 4.5 million placentas (multiples not counted) at charges of $750 for both hospital and professional charges, an approximately $3.375 billion price tag would attach.