ABSTRACT
Substance abuse is a major public health issue in all over the world. The types and ingredients of drugs used in our country are different from other countries. The study was conducted to determine relationship between substance abuse during pregnancy, and perinatal complications in Iran. A retrospective cohort study was carried out over a 6 years period on all the substance user pregnant women [519 cases] and 519 non users attending 4 major educational university hospitals labor ward. All the substance user pregnant mothers abusing heroin, opium, crack, cannabis, crystal, methadone, and polydrug were included and compared to non-exposed ones. Our study demonstrated a 0.5% prevalence of substance abuse in pregnant women. Opium [62.6%] was the most prevalent substance followed by crack [20.3%]. Pre-term birth was higher in all substance user groups, the most in crack group [45.8%] with relative risk of 2.55. Neonatal abstinence syndrome developed in 38.7% of infants born of addicted mothers [40.4% crack, 38.6% opiates, 35.3% crystal and 45.5% poly drug use]. Neonatal birth weight of infants of mothers using crack, opium and polydrug were significantly lower to non users [P<0.05]. Neonatal Intensive Care Unit [NICU] admission in substance using mothers was significantly higher than non-users [P < 0.001]. Neonatal death was 10.1% in crack group [RR=3.48] and 5.8% in opium user group [RR=2.79] with significant difference with non-users [P<0.05]. The frequent types of substances used during pregnancy in our country are different from others [opium was the most prevalent substance]. Subsequently the frequencies of the complications during pregnancy are different. Substance abuse during pregnancy has increased risk of pre-term birth, Small for Gestational Age, NICU admission and neonatal death