Diminished ovarian reserve is not associated with increased risks of preterm birth or low birth weight

Abstract

OBJECTIVE: Infertility and in-vitro fertilization (IVF) are associated with increased risks of preterm birth (PTB) and low birth weight (LBW). We sought to determine if diminished ovarian reserve (DOR) mediates the increase in these perinatal morbidities. DESIGN: Retrospective cohort. MATERIALS AND METHODS: From the 2008 national SART database, we selected all patients who underwent a fresh non-donor IVF cycle resulting in a singleton live birth. We further restricted the cohort to patients with a recorded follicle stimulating hormone (FSH) value (N=14,262). Log binomial models were created to assess the associations between FSH and PTB (<37 weeks), FSH and LBW (<2500g), DOR (defined as FSH≥10mIU/ml) and PTB, and DOR and LBW, adjusting for age, ethnicity, nulligravidity, history of preterm birth, smoking status, body mass index and infant gender. RESULTS: As FSH values rose, risk of PTB and LBW declined. DOR was associated with a lower risk of both PTB and LBW.Tabled 1Relative Risk (95% Confidence Interval)UnadjustedAdjustedFSH∗mIU/ml. & PTB0.97 (0.96-0.99)^per unit change in FSH.0.98 (0.96-1.00)^per unit change in FSH.FSH∗mIU/ml. & LBW0.97 (0.95-0.99)^per unit change in FSH.0.98 (0.96-1.00)^per unit change in FSH.DOR & PTB0.87 (0.78-0.97)0.94 (0.79-1.11)DOR & LBW0.86 (0.76-0.98)0.90 (0.77-1.06)∗ mIU/ml.^ per unit change in FSH. Open table in a new tab CONCLUSION: Contrary to our initial hypothesis, an FSH value suggesting DOR appears to be protective against PTB and LBW. The patient characteristics that contribute to the increased risk of perinatal morbidity in infertile couples remain to be determined.