Hii , Welcome To HCM & Thanks For Asking Your Query Here however there is no established medical proof linking sleep apnea with low sperm count but there are many studies showed that men with disturbed or poor sleep have a reduced sperm count compared to men who reported restful sleep semen has many component and sperms are one of them ,the whitish opalescence of semen is due to the protein it contains and watery semen may be caused by poor diet also as you mention the semen is very watery , it is necessary to get it examine in that case a thorough examination of semen will reveal everything including quantity of sperms and also mobility and quality of sperms along with this he should be treated for sleep apnea too remember it needs just one sperm to fertilize the egg , so even if your hubby has low sperm count there are many ways to get pregnant in today s advance world including Artificial insemination and IVF etc i would strongly suggest you to never loose hope & see Your Dr to rule out the real cause behind your problem I hope it help Thanks & Get well Soon