An interpregnancy interval of <12 months is associated with increased rates of preterm delivery in singleton live births from in vitro fertilization (IVF), a new study found. The national cohort included patients with a history of live birth from assisted reproductive technology who returned for a fresh, autologous IVF cycle from 2004 to 2013. Interpregnancy interval was defined as the interval from live birth to cycle start. Researchers found:
- Of 51,997 fresh IVF cycles after an index live birth, 17,536 resulted in a repeat live birth with 11,217 singleton live births from autologous IVF.
- An interpregnancy interval of <18 months occurred in 40.9% of cycles.
- An interpregnancy interval 6 to <12 months was associated with a 3.0% increase in preterm delivery and a 2.7% increase in low birth weight compared with an interpregnancy interval of 12 to <18 months.
- The data support delaying the start of IVF treatment 12 months from a live birth.
Quinn MM, Rosen MP, Huddleston HG, Cedars MI, Fujimoto VY. Interpregnancy interval and singleton live birth outcomes from in vitro fertilization. [Published online ahead of print June 6, 2018]. Obstet Gynecol. doi:10.1097/AOG.0000000000002644.