About 5,000 infertile couples in Guangdong province are looking for sperm donors, but as many as 80 percent of them have failed due to limited supply, the provincial sperm bank said on Monday.

Infertility is becoming a serious problem, with approximately one in six couples experiencing difficulties conceiving during their reproductive life. In around a third of these, failure to achieve pregnancy is due to an abnormality or possibly an absence of spermatozoa in the male partner's semen.

"I have been married to my husband for five years, but we failed to have a baby as my husband is infertile," Yang, a Guangzhou resident in her 30s, said.