The Incidence of Neonatal Abstinence Syndrome in Babies Born to Women with Sickle Cell Disease: A Single Center Study

Little is known about the neonatal outcomes of infants born to mothers with SCD. Women with SCD are often treated for pain with opioid medication either intermittently or chronically throughout pregnancy. The incidence of withdrawal or neonatal abstinence syndrome has not been well described making counseling of these women about the risks and benefits of opioid therapy during pregnancy difficult. The objective of this study was to determine the incidence of neonatal abstinence syndrome (NAS) in babies born to women with sickle cell disease.

All pregnancies in women with sickle cell disease were identified within the Johns Hopkins Hospital between January 1, 2001 and January 1, 2011. Retrospective data collection was performed using the electronic medical record. Demographic and outcome information recorded included maternal age, gestational age at time of delivery, outcome of pregnancy, maternal genotype, neonatal intensive care unit (NICU) admissions, neonatal abstinence syndrome diagnosis and neonatal length of stay. Student t-tests and chi square analysis were used to compare outcomes as appropriate.

69 unique patients were identified. From these 69 women, 94 pregnancies were identified. Of these 94 pregnancies, 83 live births were noted. The other 11 pregnancies included 3 spontaneous abortions, 3 ectopic pregnancies, 4 terminations and 1 fetal death in utero. The mean maternal age at time of delivery was 25.5 +/− 5.1 years. The mean gestational age was 36 weeks 2 days (median 36 weeks 6 days with a range of 31 weeks 4 days to 39 weeks 3 days). Of the 83 live births noted in this retrospective cohort, 22 (27%) of these infants were admitted to the NICU and17 (20%) were diagnosed with neonatal abstinence syndrome. Of the 17 infants born with NAS, 12 infants (70%) were born to mothers with SS disease, 3 infants (18%) to mothers with Sβthalassemia and 2 infants (12%) to mothers with SC disease. 53% of babies born with NAS were delivered by C-section which was not statistically significantly different than babies born without NAS (42% p=0.60) The mean birth weight of the babies with NAS was 2521 grams compared to babies without NAS which was 2853 grams (p=0.07). 59% of babies with NAS required NICU care compared to 16% of babies without NAS (p<0.001). The mean length of stay for babies with NAS was significantly longer than those babies without NAS (14.7 days vs. 5.8 days, p=0.003). Of the babies without NAS, 44% had extended hospital stays due to baby-associated complications and the mean LOS was 10.6 days; 10% had extended hospital stays due to complications of the mother with a mean LOS of 6.5 days; and the mean LOS for the 45% of those without mother or baby complications was 2.5 days.

Current recommendations include the use of opioids as needed for vaso-occlusive pain in pregnancies complicated by sickle cell disease. While effective, our study demonstrates that a significant percentage of infants exposed to opioids in utero develop neonatal abstinence syndrome. Future studies are indicated to delineate a dose-response relationship if one exists as well as alternative therapies to address this newly recognized important neonatal co-morbidity.

Lanzkron:Hemaquest: Membership on an entity's Board of Directors or advisory committees; NHLBI: Research Funding.