https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5951714/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3650450/https://academic.oup.com/humupd/article/19/3/232/727781https://americanpregnancy.org/getting-pregnant/infertility/in-vitro-fertilization-70966/https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6351582/