Impact of Placenta Previa on Fetal Growth

Abstract

Background: Placenta Previa refers to the presence of placental tissue that extends over the internal cervical is during pregnancy. The incidence of this condition is reported to be 2% at 20 weeks of gestation and decreases to around 4–6 per 1000 births between 34 and 39 weeks through trophotropism. The aim of the work is to evaluate fetal growth in pregnancies complicated by placenta Previa. Methods: This cross-sectional study was done on 100 pregnant females with placenta Previa aged 18-35 years. Cases were defined as patients with gestational age 24-40 weeks, BMI 18-30 kg/m2, Singleton fetus and diagnosed having placenta Previa; confirmed by trans-vaginal ultrasound in the second and third trimester. Complete history, vital signs and complete obstetric examination, laboratory and radiological investigations (ultrasound done trans-abdominally to evaluate fetal weight, biometry and Doppler studies) were taken. Results: The gestational age ranged from 34-39 weeks with a mean value 36.03 ± 1.23 weeks and a median value 36 weeks (IQR = 35-37 weeks). The femur length ranged from 33.14-39.14 weeks with a mean value 35.44 ± 1.56 weeks and a median value 35.14 weeks (IQR = 34-36.9 weeks).The abdominal circumference ranged from 32.86-39.14 weeks with a mean value 35.43 ± 1.65 weeks with a median value 35.14 weeks (IQR = 33.9-36.7 weeks). As regard to umbilical (UA) and middle cerebral (MCA) arteries Doppler resistant index (RI), UA ranged from 0.48-0.58 with a mean value 0.53 ± 0.03 and a median value 0.53 (IQR = 0.51-0.55). MCA ranged from 0.75-0.85 with a mean value 0.80 ± 0.03 and a median value 0.79 (IQR = 0.77-0.82). Conclusion: Placenta Previa led to preterm delivery (<36 weeks) in about one third of the study cases. Femur length was <36 weeks in 65 patients. Abdominal circumference was <36 weeks in 61 patients. Placenta Previa had insignificant effect on umbilical (UA) and middle cerebral arteries Doppler resistant index.