Gross presentation and histomorphological changes of placentae in patients presenting with intrauterine foetal death at Kenyatta National Hospital

Abstract

Background: A stillbirth or intrauterine foetal death (IUFD) is defined as a product of conceptionweighing ~500g or with gestational age >22 weeks without evidence of life at birth but other authors regard the lower gestational age as 20 weeks. There are 3.2 million annual stillbirths, at least 98% occur in low-/middle-income countries. Stillbirth rates are below 5 per 1000 in developed countries but approximately 32 per 1000 in developing countries.The rate of abnormal placental pathology in stillbirths range from 20% to 40%. The most useful tests used in the diagnosis of the cause of IUFD are histopathological examination of the placenta, umbilical cord and the foetus. Despite placenta being a source of information as to the cause of death, pathological examination of the placenta is onlyperformed in 25% of stillbirths in developing countries. Objective: To determine gross presentation and histomorphological changes of placentae in patients presenting with intrauterine foetal death as compared to live births. Study design: This was a case control study. Methodology: Clients presenting with IUFD at gestation of 28 weeks and above were recruited after confirmation with ultrasound results. The stillbirth was weighed and examined after delivery then noted whether it was macerated or fresh. The placenta was weighed and then examined grossly together with the umbilical cord and membranes and then immediately fixed in 10% formalin and submitted for histopathology examination. Clients who delivered live births comprised the controls and were matched for age. Setting: The study was conducted at the Kenyatta National Hospital's labour ward. Kenyatta National Hospital is Kenya's largest referral hospital, located in the capital city Nairobi. Data: The data was collected using a structured questionnaire. It was then entered into a password protected Ms Access database. Data analysis was performed using Statistical Package for Social Scientists (SPSS Version 17.0). Vll Measures of outcome: The morphological patterns of placentae from mothers who presentedwith IUFD were compared to those of mothers who delivered live births. Results: There was more pathology in the placenta from stillbirths compared to the live births.Reduction of the mass of functioning villi was present in 11.8% of placenta in the stillbirthgroup compared to 2% in the live birth group (p value-O.002). 16.7% of placenta in the stillbirth group had haematomas and/or thrombi compared to 7.8% in the live birth group (p value-O.017).There was significant presence of other placental abnormalities in the stillbirth group (22.5%) compared to the live birth group (9.8%) (p value-O.002). However, there were no significant differences between the 2 groups involving abnormalitiesof fetal stem arteries (p value-O.SS8). Conclusion: Histological examination of placenta may help in identifying some causes of stillbirths. This knowledge may lead to preventive measures which would lower perinatalmortality.