Placenta Structure of Patient With Fresh Stillbirth at Pumwani Maternity Hospital in 2021 - an Unmatched Case Control Study

Abstract

Background: Globally approximately 2.65 million stillbirths occur annually. This gives an estimate of over 7100 deaths per day. Most (98%) of these stillbirth cases occur in low and middle-income countries including sub-Saharan Africa. Fresh stillbirth is defined as death that has occurred in the last 12 hours before the expulsion of the product of conception at or above 20 weeks of gestation. The fresh stillbirth rate in Kenya was noted to be 19.7 per 1000 births as of 2019. It is estimated that 50% of stillbirths occur intrapartum. Around 8-20% of intrapartum deaths are classified as unknown causes without conclusive examination of the placenta. Examination of placenta in cases of stillbirth is not routinely practiced in sub-Saharan Africa despite placenta being vital organ which can elucidate on cause of stillbirth. Our aim is to assess placental pathology in cases of fresh stillbirth. Objective: To compare the differences of gross morphology and histology of placentae of patients with fresh stillbirth and patients with livebirth.at Pumwani maternity hospital. Methodology: This was a case-control study involving a total of 88 placentae of which 44 placentae were FSB (cases) versus 44 live births placentae (controls) at Pumwani Maternity hospitals. Informed consent was signed by the participants. A structured questionnaire was administered to collect socio-demographic and reproductive health information. Placentae were collected, refrigerated between 2°- 4° Celsius. Photographs were taken of the maternal and fetal surfaces of the placentae. The gross morphology of both cases and controls were simultaneously recorded. Afterwards we made cut sections from placenta disc: 3 from central location and 3 from peripheral location. After the completion of placentae collection, blocks and later slides were made for microscopic histological examination. The socio-demographic and clinical characteristics of the study participants such as age, gestation age, and parity were calculated and presented as tables of frequencies. The proportion of women presenting with FSB and those with abnormal placental histology were estimated using simple frequencies. Pearson’s correlation was used to assess the correlation between the maternal demographic and clinical characteristics and the placental changes with FSB Data was analysed using SPSS v.21 for both descriptive and inferential analysis. xii Results: A total of 88 placentae were analysed. (44 FSB and 44 live birth). The mean age of cases and control were 29.2 (±6) and 26.2(±5). In assessing gross morphology of the placenta disc; mean placental mean weight was lower in cases (398.4g) than controls (440.65g) p (value=0.041). Retro-placental hematoma were more in cases OR 4.19(1.24,14.13) p=0.002. There were no statistically significant findings in other gross morphology of placental disc (shape length and width calcification, and infarction). There was no statistical difference in gross morphology of umbilical cord between the two groups. In Assessing gross morphology of the membranes; Green colour was statistically significantly associated with fresh stillbirth OR 5.92(1.1, 330.65) p-value =0.04. In the histology of placenta disc, villitis AOR-5.7(1.82-25.2) p=0.004, fetal thrombotic vasculopathy 6.4(1.73, 26.03) 0.016, villous vascularity AOR 6.94(2.4, 20.84) p<0.001 were significant. In our secondary objective, assessing socio-demographic, medical and obstetric risk factors older maternal age >35(p=0.043), lower maternal education (primary education p=0.013), lower birth of weight <2500g (p=0.0046) referral from other facility (p=0.036) were identified. Conclusion: Lower placental weight retro- placental hematoma green colour membrane was associated with fresh stillbirth. In histology villitis, villous vascularity, and fetal vasculopathy were significantly associated with fresh stillbirth. Utility: The study findings will play critical roles towards preventing fresh stillbirth; thereby, reducing the stillbirth rate. Also, placental examination can identify the cause of stillbirth can yield recommendations for the management of future pregnancies, provide a risk of recurrence, and give families a sense of closure