The InVivo and InVitro Effects of Sildenafil (Viagra) on Oocyte and Embryo Development

.. 7
1.2.1 Physiology of Fertilization and Implantation Process …..……. 9
1.2.2 Physiology of Ovarian Function and Reproductive System .… 12
1.3 Ways on How Secretion of Ovary Controls the Reproduction …………… 16
1.4 Historical Development, Chemical Composition, and Mechanism of
Action ……………………………………………………………………………………………. 18
1.4.1 Historical Development of Sildenafil Citrate ………………………. 18
1.4.2 Chemical Composition of Sildenafil Citrate ……………………….. 20
1.4.3 Mechanism of Action ………………………………………………………. 22
1.5 Sildenafil Citrate and Ovarian Response ……………………………….….. 24
1.5.1 Possible Effects of Sildenafil Citrate on Female Reproduction . 24
1.5.1.1 Treating Female Sexual Arousal Disorder ……… 24
1.5.1.2 Effects of Sildenafil Citrate on the
Endometrium Lining ……………………………. 26
1.5.1.3 Effects of Sildenafil Citrate on Oocyte …………. 28
1.5.1.4 Effects of Sildenafil Citrate on the Embryonic Development …………………………………….. 29
1.6 Purpose and Rationale behind the Purpose of this Study …………..……… 31
1.7 Research Hypothesis ………………………………………………………. 33
1.8 Overall Objective …………………………………………………………. 33
1.8.1 Specific Objectives ……………………………………………. 33
References ………………………………………………………………………………… 35 – 43
Chapter I – Introduction
1.1 Infertility Problems in Women…
12). It means that infertility happens when a couple failed to conceive after they had unprotected intercourse for a time span of 12 months. In general, infertility is classified as either primary or secondary infertility. Primary infertility means that the couple had never conceived a child despite their willingness to get the wife pregnant whereas secondary infertility happen when the couple is having difficulty getting pregnant after a pregnancy or having at least one child or more (NHS, 2012. Camacho, Gharib and Sizemore, 2007, p. 138. Inhorn and van Balen, 2002, p. 12). Boivin et al. (2007) revealed that roughly 80 million couples around the world are having difficulty conceiving a child. In UK, the NHS reported that around 3.5 million individuals or one out of six couples are facing problems related to infertility (NHS, 2012). There are quite a lot of factors that can lead to infertility. Based on the study that was conducted by the World Health Organization (WHO), these factors were identified as: female reproductive disorders (38%), biological abnormalities in men and women (27%), male reproductive disorder (20%), subfertility (10-15%), and unknown causes (15%) (Kretser, 1997). The term “idiopathic” means that there is no specific known cause for a given disorder (Falcone, 2006, p. 58). Therefore, idiopathic amenorrhoea means that there is an unknown cause behind the absence of menstruation. Although problems related to infertility may not cause serious threat on the physical health of a couple, it will always remain a fact that their inability to conceive a child may trigger serious harm on their social and mental well-being. Among