Objective: This prospective cohort study evaluated the relationship between fertility treatments and the prevalence and outcomes of dichorionic discordant twins. This issue has gained importance due to twin gestations resulting from fertility treatments.
Study design: Mothers of dichorionic twin pregnancies achieved in a single fertility clinic by assisted reproduction techniques, who had completed the first trimester of the pregnancy, were prospectively enrolled. Pregnancies with major fetal anomalies were excluded. Data regarding concordant and discordant twins based on the fertility treatments given to achieve the pregnancies were analyzed to determine the prevalence of discordance and pregnancy outcomes.
Results: A total of 571 dichorionic twin pregnancies were available for evaluation. Fertility treatments modalities, sperm quality and implantation of cultured and thawed embryos did not influence the rate and severity of discordant twins. Increased hospitalization rates were found among discordant (n=108) compared to concordant (n=463) twins (47.2% vs. 31.3%, P<0.0001) and higher rates of betamethasone treatment (65.7% vs. 28.9%, P<0.0001). Secondary analysis of discordant pregnancies with a growth restricted twin, revealed the same results. We found no association between various fertility treatments and twin discordance.
Conclusions: Our data suggest that fertility treatments do not play a major role in the pervasiveness and outcome of discordant twin pregnancies.