ESHRE 2021: 37th Annual Meeting
Virtual, 26 Jun – 1 July 2021
ESHRE 2021, spanning across six full days of scientific sessions, pre-congress courses, Journal Club and informal coffee breaks, covered a myriad of topics within ART, from reflecting on the past, deliberating the present and highlighting future disruptors.
One of those long-standing deliberations included the safety of children born through ART. There have been many studies looking at short-term outcomes of ART, given that national birth registries exist in several countries, providing large cohort data for ART children and adolescents. However, long-term outcomes of ART have been sparse, due to the lack of large general data on children’s health. The most recent summary of large registry studies, systematic reviews or cohort studies by Bergh and Wennerholm (2020) looked at neurodevelopment including cerebral palsy (CP), cognitive development, attention deficit hyperactivity disorder (ADHD) and autism spectrum disease (ASD), growth, cardiovascular function, diabetes type 1, asthma, malignancies, and reproductive health. They highlighted significantly increased associations of ADHD, ASD, CP in general ART children and cardiovascular function in singletons born through ART. Additionally, they cautioned towards evidence for increased risk of Diabetes Type 1 and childhood malignancies in ART children born from cryopreserved embryos.
In their prospective, observational, ‘Growing Up Healthy Study’ of 303 ART-conceived adolescents, born 1991-2001 in Western Australia, Wijs, et al., (ESHRE 2021) contradicted previous evidence on contra-indications of cardiovascular function in ART children. They showed that no significant differences were detected following serum fasting levels of glucose, insulin, LDL cholesterol, total cholesterol, cholesterol/HDL-ratio, triglycerides, etc. Additionally, no significant differences in blood pressure or heart rate were detected. Another large Nordic registry study [singleton live births N =5,076,444 after ART (n= 116,909) or SC (n= 4,959,535), between 1995 and 2014] from the Committee of Nordic ART and Safety (CoNARTaS) group by Rönö et al., (ESHRE 2021) looked at differences in neurodevelopmental disorders between singletons born after ART and spontaneous conception (SC) until young adulthood.
While some of these studies are re-assuring, caution must be taken especially for frozen embryo replacement
This study re-established previously found evidence towards increased risk of learning and motor functioning disorders, ASD and ADHD, with similar likelihood for children from ICSI or IVF and fresh or frozen embryos. Finally, Spaan et al., (ESHRE 2021) showed some promising data on cancer risk in children born after ART. In their nationwide cohort study of 98,165 live-born children, (N=53,154 ART-conceived and N=45,211 non-ART conceived, (conceived naturally with or without ovarian hyperstimulation) by sub-fertile women, no significantly increased site-specific cancer risk was found in ART children, with a median follow-up age of 17 years. Additionally, there were no increased risk for children born after ICSI or frozen embryo replacement. While some of these studies are re-assuring, caution must be taken especially for frozen embryo replacement as suggested by the increased likelihood of large for gestational weight and its consequent correlation with increased risks of childhood malignancies, breast cancer, hypertension and Diabetes Type 1 in children born from frozen embryos (Magnusson et al., ESHRE 2021).
It is worth noting that all the above studies have several limitations in terms of being observational, lack of sub-group analyses for length or cause of infertility, age, lifestyle factors (substance use, smoking), types of cancer etc. Nonetheless, each of these studies are significant in gathering much needed evidence towards continuous monitoring of long-term health of children born through ART, especially in light of the highly evolving status of the field in which newer technologies are often adopted sooner than evidence must allow.
Sourima Biswas Shivhare (awarded an ARCS meeting/education grant)