In 2015, Nigeria's estimated 317,700 stillbirths accounted for 12.2% of the 2.6 million estimated global stillbirths. This suggests that Nigeria still makes substantial contribution to the global burden of stillbirths. This study was conducted to determine the prevalence and identify the causes and factors associated with stillbirth in eight referral hospitals in Nigeria.This was a cross-sectional study of all deliveries over a period of 6 months in six general hospitals (4 in the south and 2 in the north), and two teaching hospitals (both in the north) in Nigeria. The study population was women delivering in the hospitals during the study period. A pre-tested study protocol was used to obtain clinical data on pregnancies, live births and stillbirths in the hospitals over a 6 months period. Data were analyzed centrally using univariate, bivariate and multivariate logistic regression analyses. The main outcome measure was stillbirth rate in the hospitals (individually and overall).There were 4416 single births and 175 stillbirths, and a mean stillbirth rate of 39.6 per 1000 births (range: 12.7 to 67.3/1000 births) in the hospitals. Antepartum (macerated) constituted 22.3% of the stillbirths; 47.4% were intrapartum (fresh stillbirths); while 30.3% was unclassified. Acute hypoxia accounted for 32.6% of the stillbirths. Other causes were maternal hypertensive disease (6.9%), and intrapartum unexplained (5.7%) among others. After adjusting for confounding variables, significant predictors of stillbirth were referral status, parity, past experience of stillbirth, birth weight, gestational age at delivery and mode of delivery.We conclude that the rate of stillbirth is high in Nigeria's referral hospitals largely because of patients' related factors and the high rates of pregnancy complications. Efforts to address these factors through improved patients' education and emergency obstetric care would reduce the rate of stillbirth in the country.Trial Registration Number NCTR91540209. Nigeria Clinical Trials Registry. http://www.nctr.nhrec.net/ Registered April 14th 2016.