Good day, Ma'am. We appreciate your feedback on our report. To answer your first two questions,
Please elaborate on the use of intermediate host oviducts in IVF. In the article, the cited study corresponding to the use of host oviducts in IVF had demonstrated that the transfer of IVF-produced embryos to heat-stressed cows can be improved by culturing the embryos in the presence of insulin-like growth factor I (IGF-I). Meanwhile, the same study had suggested that further study must be done to determine whether increased pregnancy rates can be associated with gonadotropin-releasing hormone (GnRH) treatment among patients. The experiment was performed by producing and culturing embryos in vitro before being transferred to the recipients with a palpable corpus luteum (Block et al., 2003).
Beyond the articles cited in the article, Rizos et al. (2010) had noted that the oviducts of various mammalian species from sheep to mice can sustain early bovine embryos that yield blastocysts of better quality compared to those cultured in vitro. Furthermore, they had highlighted that trans-species transfer of in vivo cultured embryos can be achieved across a broad range of species leading to the blastocyst stage.
The review had highlighted the significance of the oviduct in assisting and providing the optimal environment for the initiation of some major developmental events postfertilization namely:
- first cleavage division,
- embryonic genome activation,
- morula compaction, and
- blastocyst formation.
Consequently, Rizos et al. had also highlighted the importance of the oviduct fluid in embryonic development considering factors such as viscosity and oxygen concentration. Similarly, the cited studies on the article had shown that the introduction of synthetic conditions simulating the oviduct liquid could influence embryo vitality and development (Block et al., 2011; Sirisathien et al., 2003).
REFERENCES
Block, J., Drost, M., Monson, R. L., Rutledge, J. J., Rivera, R. M., Paula-Lopes, F. F., Ocon, O. M., Krininger, C. E. III, Liu, J., & Hansen, P. J. (2003), Use of insulin-like growth factor-I during embryo culture and treatment of recipients with gonadotropin-releasing hormone to increase pregnancy rates following the transfer of in vitro-produced embryos to heat-stressed, lactating cows.
Journal of Animal Science, 81(6), 1590-1602. https://doi.org/10.2527/2003.8161590x.
Block, J., Hansen, P. J., Loureiro, B., & Bonilla, L. (2011). Improving post-transfer survival of bovine embryos produced in vitro: Actions of insulin-like growth factor-1, colony stimulating factor-2 and hyaluronan.
Theriogenology, 76(9), 1602-1609. https://doi.org/10.1016/j.theriogenology.2011.07.025.
Rizos, D., Ramirez, M. A., Pintado, B., Lonergan, P., & Gutierrez-Adan, A. (2010). Culture of bovine embryos in intermediate host oviducts with emphasis on the isolated mouse oviduct.
Theriogenology, 73(6), 777–785. doi:10.1016/j.theriogenology.2009.10.001.
Sirisathien, S., Hernandez-Fonseca, H. J., & Brackett, B. G. (2003). Influences of epidermal growth factor and insulin-like growth factor-I on bovine blastocyst development in vitro.
Animal Reproduction Science, 77(1-2), 21-32. https://doi.org/10.1016/S0378-4320(02)00272-5.
What synthetic products are used to enhance the success of IVF? Choudhary et al. (2016) had discussed the recent advances in reproductive biotechnologies. While they had identified in vitro maturation, fertilization, and culture collectively as a reproductive technology itself, they had also noted other technologies preceding and succeeding IVF like sperm encapsulation for preservation, seminal biomarkers for fertility prediction, ovum pick up for oocyte recovery, embryo transfer technology, and embryo cryopreservation.
Meanwhile, Panesar (2016) had highlighted the chemicals used in different procedures of IVF. For one, controlled ovarian stimulation can be done using GnRH-analogues and natural steroid inhibitors like clomiphene citrate, menotropins, urofollitropin, highly purified and recombinant follicle-stimulating hormone (FSH), and luteinizing hormone (LH). Ovulation can then be induced by the likes of human chorionic gonadotropin (hCG) or a GnRH agonist. Finally, progesterone supplementation or hCG supplementation is used for luteal-phase support.
REFERENCES
Choudhary, K. K., Kavya, K. M., Jerome, A., & Sharma, R. K. (2016). Advances in reproductive biotechnologies.
Vet World, 9(4), 388-395. doi:10.14202/vetworld.2016.388-395.
Panesar, K. (2016, September 16). Medications used for in vitro fertilization. US Pharmacist. https://www.uspharmacist.com/article/medications-used-for-in-vitro-fertilization.
