Published online Jul 10, 2015. doi: 10.4239/wjd.v6.i7.936
Peer-review started: October 21, 2014
First decision: January 20, 2015
Revised: February 23, 2015
Accepted: March 30, 2015
Article in press: April 2, 2015
Published online: July 10, 2015
Processing time: 263 Days and 14.6 Hours
Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects up to 6.8% of reproductive age women. Experimental research and clinical observations suggest that PCOS may originate in the very early stages of development, possibly even during intrauterine life. This suggests that PCOS is either genetically-transmitted or is due to epigenetic alterations that develop in the intrauterine microenvironment. Although familial cases support the role of genetic factors, no specific genetic pattern has been defined in PCOS. Several candidate genes have been implicated in its pathogenesis, but none can specifically be implicated in PCOS development. Hypotheses based on the impact of the intrauterine environment on PCOS development can be grouped into two categories. The first is the “thrifty” phenotype hypothesis, which states that intrauterine nutritional restriction in fetuses causes decreased insulin secretion and, as a compensatory mechanism, insulin resistance. Additionally, an impaired nutritional environment can affect the methylation of some specific genes, which can also trigger PCOS. The second hypothesis postulates that fetal exposure to excess androgen can induce changes in differentiating tissues, causing the PCOS phenotype to develop in adult life. This review aimed to examine the role of fetal programming in development of PCOS.
Core tip: Polycystic ovary syndrome (PCOS) is a highly complex and heterogeneous disorder that is significantly influenced by genetic and environmental factors. There is some evidence that the development of PCOS may begin during the intrauterine period. Fetuses exposed to intrauterine nutritional restriction often have lowered insulin secretion and, as a compensatory mechanism, insulin resistance, which is known as the “thrifty” phenotype. Additionally, an impaired intrauterine nutritional environment can affect the methylation of some specific genes, which can trigger PCOS. The other hypothesis postulates that fetal exposure to excess androgen can induce changes in differentiating tissues, causing the PCOS phenotype and related disorders to develop in adult life.