O-15: Anovulation may be a risk factor for major birth defects in children born after infertility treatment

Abstract

We recently reported a slight but significant increase in major birth defects in infants conceived by IVF procedures and a slight and non-significant increase in infants born after IUI procedures compared to matched controls. Our purpose was to further evaluate the same database for risk factors for birth defects after infertility treatments. Retrospective analysis of 1805 infants born to 1134 women following infertility treaments (both IVF and IUI) with 107 of these infants being diagnosed with at least one major birth defect by one year of age. The generalized logit model fitted using the generalized estimating equations method was used to identify risk factors associated with major birth defects while accounting for the correlation among births from the same mother. Individual risk factors were then fitted into a multi-factor model to determine significant independent variables. Variables examined included infertility treatments used, parental demographic data, sex and plurality of the infant, maternal BMI, and infertility diagnoses. Attending physicians made infertility diagnoses prior to the IVF cycle and these included tubal factor, male factor, endometriosis, cervical factor, polycystic ovarian syndrome (PCOS), and ovulatory factor not otherwise specified. For the infertility diagnosis variable, 28 infants had to be excluded due to missing data. By univariate analysis, factors that were significantly associated with an increased risk of a major birth defect were high order multiple gestations (but not twins), male gender, and the combined infertility diagnostic categories of ovulatory factor/PCOS (see table). The 73 infants born to mothers with a definite diagnosis of PCOS had a 13% incidence of birth defects with an odds ratio of 2.53 (95% CI of 1.20, 5.34, p=0.02), although the numbers in this group were small. Maternal BMI was not a risk factor. The diagnosis of endometriosis did not quite reach statistical significance as a risk factor. By multivariate analysis, high order multiple birth, male gender and PCOS/ovulatory factor remained as significant risk factors for birth defects following infertility treatments.Tabled 1 This is the first study to link birth defects with a maternal infertility diagnosis. Ovulatory dysfunction and PCOS appear to contribute to the risk for birth defects following treament. As we seek safe outcomes from infertility care, reducing multiple gestations should be a priority for many reasons including the avoidance of birth defects.