Comparison of Clinical Characteristics of Preterm Twins: In Vitro Fertilized versus Spontaneous Conceived

ABSTRACT

PURPOSE: With in vitro fertilization (IVF) becoming a common treatment for infertility, there has been an increasing number of studies on perinatal complications related to IVF. This study compares the clinical characteristics of twins at gestational age less than 34 weeks, between IVF and spontaneous conceived. METHODS: We retrospectively reviewed the medical records of 138 preterm twins at gestational age less than 34 weeks, admitted between January 2009 and December 2011 to the neonatal intensive care units of two hospitals. Maternal and preterm infant's clinical characteristics of 58 IVF and 80 spontaneous conceived twins were compared. RESULTS: Maternal age was older in IVF twins (33.3+/-2.8 vs. 31.3+/-4.2, P-value=0.007), and there was no other significant difference between the two maternal groups. Gestational age was lesser in IVF twins (30.6+/-3.2 vs. 31.2+/-2.7, P-value=0.048). Age at the day of full enteral feeding (24.2+/-12.1 vs. 18.2+/-13.2, P-value<0.001) and age at day of full oral feeding (30.1+/-18.5 vs. 25.3+/-19.2, P-value<0.001) were significantly longer in IVF twins as adjusted by gestational age. Retinopathy of prematurity (ROP) showed higher incidence in IVF twins (P-value=0.011), but there was no significant difference between the two groups after adjusting gestational age. CONCLUSION: The clinical characteristics in IVF twins at gestational age less than 34 weeks were not significantly different from those of spontaneously conceived twins except age at the day of full enteral feeding and age at the day of full oral feeding after adjusting by gestational age.