Background: The use of gonadotrophin-releasing hormone agonists (GnRHa) in in vitro fertilisation (IVF) cycles is accepted as standard practice. However, the safety profile of this drug with inadvertent exposure in pregnancy is still in question.
Aim: To evaluate the pregnancy outcomes in a group of infertile patients who conceive spontaneously while undergoing IVF with unrecognised daily exposure to GnRHa during the downregulation regime.
Methods: A review of all women undergoing planned treatment cycles in our IVF centre, comprising of a total of 1949 fresh and 154 frozen embryo cycles from January 1996 to December 2001. All spontaneous pregnancies were recorded and case records reviewed.
Outcome measure: Course and clinical outcome of pregnancies.
Results: Nine spontaneous pregnancies were recorded (0.43%). The median duration of inadvertent exposure to subcutaneous leuprolide acetate was 22 days (range 21-25). The median age of the patients was 35 years (range 28-39) and the median duration of infertility was 3.5 years (range 1.5-8). Nine pregnancies resulted in miscarriages. Seven pregnancies progressed to term and resulted in singleton live births with no apparent evidence of fetal abnormalities or aneuploidies. One pregnancy was complicated by parvovirus infection at 19 weeks gestation with transient fetal hydrops. The pregnancy outcomes appear favourable even when compared to those conceived through the completed IVF cycles within the same cohort.
Conclusion: Our experience reaffirms current evidence from earlier studies that accidental exposure to GnRHa in early pregnancy is safe. However, we believe that contraception prior to GnRHa is still prudent pending definitive data.