Exposure to corticosteroids in the first trimester is associated with an increased risk of urogenital congenital anomalies

Does maternal exposure to first trimester corticosteroids in IVF/ICSI treatment result in an increased risk of congenital anomalies?Children born with the aid of IVF/ICSI whose mothers were treated with adjuvant corticosteroids during the first trimester had an increased risk of cryptorchidism, hypospadias and talipes.Maternal exposure to corticosteroids may increase the risk of congenital anomalies such as cleft palate and neural tube defects. However, the existing studies have conflicting outcomes, are underpowered, and do not study a population undergoing IVF/ICSI, a group known to be at increased risk of abnormalities.This retrospective cohort analysis covering Monash IVF fertility clinics in Melbourne, Australia assessed the outcomes of 12 426 live births from both fresh and frozen embryo transfers between 2010 and 2016.There were 618 live births included in our study group of mothers exposed to corticosteroids (oral prednisolone or dexamethasone) during their IVF/ICSI treatment, with the remainder of births not exposed to steroids (control, n = 11 808). The primary outcome measured was the presence of congenital anomalies and secondary outcomes were birth weight and gestation length. Multivariate binary logistic regression was used to assess the independent effects of corticosteroid exposure and the freezing of embryos, with adjustment for maternal age at oocyte retrieval, smoking status, number of cycles taken, BMI, etiology of the infertility and the use of ICSI. Results are presented as incidence rate ratios (IRRs) with 95% CIs.Amongst 12 426 live births, and 597 birth defects, multivariate logistic regression demonstrated there was an increased incidence in talipes equinovarus (1.33% vs 0.32%, adjusted IRR = 4.30, 95% CI = 1.93, 9.58; P < 0.001), hypospadias (0.66% vs 0.18%, adjusted IRR = 5.90, 95% CI = 2.09, 16.69; P = 0.001) and cryptorchidism (0.83% vs 0.19%, adjusted IRR = 5.53, 95% CI = 1.91, 15.42; P = 0.001) in the offspring of mothers exposed to corticosteroids compared to those who were unexposed. The incidence of neither neural tube defects nor cleft palate were significantly increased in babies exposed to corticosteroids. The sex ratio of infants exposed to corticosteroids during a fresh embryo transfer cycle significantly favored males but reverted to the normal sex ratio in infants conceived in frozen embryo transfer cycles.This was a retrospective observational cohort study using administrative datasets with the potential for measurement error and unobserved confounding. Missing outcome data were obtained from patients using self-report leading to possible ascertainment bias. Given the rare incidence of some of the anomalies assessed, the study was underpowered to identify differences in abnormality rates for some specific anomalies.The findings of this study, the largest of its kind, suggest that caution should be heeded when prescribing corticosteroids to women undergoing IVF/ICSI, given that this study has now identified three previously unassociated serious neonatal complications (talipes, hypospadias and cryptorchidism), plus a potential alteration in sex ratio. Physicians should be careful in using corticosteroids in the critical first trimester and should counsel patients regarding the potential risks of this treatment.There was no funding sought or obtained for this study. K.T., V.T., B.V. and D.Z.-F. are employees or contractors to Monash IVF and hold a minority stock position in Monash IVF. R.J.W. reports no conflict of interest.N/A.