A retrospective review of recurrent preterm birth and use of highly effective reversible contraceptives

      Objectives: A history of preterm birth is the strongest predictor for subsequent preterm birth. Highly effective reversible contraception (HERC) may reduce the risk of subsequent preterm birth. This study examines the likelihood of recurrent preterm birth among women who received a highly effective reversible contraceptive compared with those who did not.
      Methods: We identified a cohort of 14,295 women from the Utah Population Database and the University of Utah Health Systems electronic data warehouse with two consecutive live births between 1996 and 2013. We assessed procedure codes for intervening contraceptive encounters and linked them with birth histories to explore the effect of HERC use between pregnancies on the risk of subsequent preterm birth (gestations less than 37 0/7 weeks).
      Results: Some 13.5% (n=1937) of first births and 11.7% (n=1682) of second births were preterm. Overall, 11.6% (n=1657) of women received an HERC device between their pregnancies, and a greater proportion of women with term index births chose HERC than those who had had a preterm birth (11.9% vs. 9.6%, p=.003). Women who had had a preterm birth who used HERC had lower incidence of subsequent preterm birth than nonusers (26.4% vs. 31.2%, p=.005). Women who used HERC between pregnancies had a reduced risk of their second birth being preterm after adjusting for age at first birth, BMI, previous preterm birth and interbirth intervals (aRR, 0.83; 95% CI, 0.71–0.97).
      Conclusions: HERC use between pregnancies is associated with a reduced risk of having a second birth that is preterm. Providers should counsel patients that HERC use between pregnancies may reduce risk of preterm birth.