Offspring of IVF

Question 1

May be an increased risk in children born from IVF

Answer 1

Prematurity
Multiple gestation
Low birth weight
LGA
Birth defects
Genetic and epigenetic abnormalities
Vascular and metabolic abnormalities

Question 2

Congenital anomalies

Answer 2

Both earlier and more recent meta-analyses suggest a 30-40% relative increased risk of birth defects in ART children, from a baseline of 2-3% to 3-4%.

Likely mostly due to patient characteristics related to their infertility more than the treatment itself. Though both may factor in.

Issues with studies:
Small numbers of participants
Pooling of exposure groups
Retrospective collection of data
Appropriateness of control group

Question 3

Genomic imprinting disorders and IVF

Answer 3

Might be increased in ICSI cycles.
Process that limits the expression of the imprinted gene from on parental allele (maternal or paternal).
Imprinted gene is where one gene is switched off through DNA methylation and so only one parents gene is expressed.
Chromosomes 6, 7, 11, 14, 15, and 20 involve imprinted genes.
Causes of genomic imprinting disorders can arise from:
1. Mutation of imprinted gene
2. Uniparental disomy (can happen through trisomy/monosomy rescue or Robertsonian translocations)
3. Changes in DNA methylation (epigenetics)

Chance of imprinting can occur in IVF due to manipulations that occur around the time of fertilisation and embryonic development that could lead to epigenetic changes.

Higher risk of Beckwith-Wiedemann syndrome, Angelman syndrome and maternal hypomethylation syndrome.

Question 4

Vascular and metabolic effects

Answer 4

Not well established.
Possibly an increased risk of metabolic disease = obesity, hypertension, insulin resistance. (Speroff)

Question 5

Prematurity and low birth weight

Answer 5

Increased risk of multiples with ART = increased risk of prematurity and low birth weight. .
After confounding from twins removed:
In a 2012 systematic review including 28,000 ART compared with non-ART singletons, the relative risks for preterm delivery less than 37 weeks and less than 32 weeks were 1.54 (95% CI = 1.47-1.62) and 1.68 (95% CI = 1.48-1.91), respectively.
Same study - The risk for small for gestational age (SGA) was also increased by 40% in ART babies (OR = 1.39, 95% CI = 1.27-1.52).