What are the changes in the placenta in intrauterine fetal death (IUFD)?

From the Guidelines

In cases of intrauterine fetal death, the placenta should be thoroughly examined to determine the cause of death, as it provides crucial diagnostic information. This examination is essential for identifying potential risk factors and underlying conditions that may have contributed to the fetal demise, such as chorioamnionitis, placental abruption, thrombosis, infarction, or vascular malformations 1.

Key Considerations for Placental Examination

• The entire placenta should be sent for pathological examination, including gross and microscopic evaluation, to identify any abnormalities or conditions that may have contributed to the fetal death.
• Before sending the placenta, healthcare providers should document its weight, dimensions, and any visible abnormalities, and consider taking photographs for further evaluation.
• Placental tissue should be collected for genetic testing if chromosomal abnormalities are suspected, using a sterile collection method to ensure accurate results.

Importance of Placental Examination

The examination of the placenta in intrauterine fetal death is critical for providing valuable insights into the cause of death, which can inform management of future pregnancies and provide closure to grieving families. According to the American College of Radiology, intrauterine fetal mortality affects close to 1% of all pregnancies, and specific maternal, fetal, and obstetric factors can increase the risk of in utero demise 1.

Recommendations for Placental Examination

• The placenta should be placed in a container with 10% formalin solution at a ratio of at least 3:1 (formalin to tissue) to preserve the tissue for pathological examination.
• A comprehensive evaluation of the placenta, including gross and microscopic examination, should be performed to identify any underlying conditions that may have contributed to the fetal demise.
• The results of the placental examination should be used to inform management of future pregnancies and provide closure to grieving families by identifying the cause of death.

From the Research

Placenta in Intrauterine Fetal Death

• The frequency of intrauterine fetal death (IUFD) with retained fetus varies, but is estimated to occur in 1% of all pregnancies 2.
• The vast majority of women will spontaneously labor and deliver within three weeks of the intrauterine death 2.
• Misoprostol regimens for the induction of labor for second and third trimester IUFDs are clinically effective, with dosages adjusted to gestational age 2.
• Clinical monitoring should continue after delivery or expulsion because of the risk of postpartum atony and/or placenta retention 2.

Induction of Labor

• Both misoprostol-alone and a combination of mifepristone plus misoprostol have been used in induction of labor in cases of intrauterine fetal death (IUFD) 3, 4, 5, 6.
• The combination of mifepristone and misoprostol may have better effects than the use of misoprostol alone, with a shorter induction-to-delivery time and lower total dose of misoprostol needed 3, 4, 5, 6.
• Pre-treatment with mifepristone may be more effective at earlier gestational weeks 3.
• A meta-analysis and systematic review found that the combined treatment was associated with more beneficial outcomes than the misoprostol alone treatment in patients undergoing labor induction in intrauterine fetal death, including a lower delivery time interval and fewer adverse effects 6.

Management of Intrauterine Fetal Death

• Mifepristone and misoprostol versus misoprostol alone for induction of labor in women with intrauterine fetal death has been compared in several studies, with the combined treatment showing more beneficial outcomes 4, 5, 6.
• The use of a combination of mifepristone and misoprostol significantly improved the rate of successful delivery and shortened the induction-delivery interval in women who had experienced fetal death compared with the use of misoprostol alone 4.
• Pretreatment with mifepristone followed by misoprostol bucally resulted in a shorter time to expulsion than treatment with misoprostol alone 5.