Have you cleansed the crystal? "
Hold it under running water or immerse it in the sea or in sea water. As you do so, hold the intention that all negativity will be washed away and the crystal reenergized. Placing the crystal in the light of the sun or moon for a few hours
There are othere ways too... but I hope this help

Other Crystals that are for fertility are;
Carnelian (esp female reproductive system)
Chrysoprase (inhances fertility and reverses infertility caused by infection)Place over female reproductive organs to bring back into balance
Moldavite
Zincite
Moonstone (aids conception, pregnancy and birth)
Cinnabar (enhances fertility)
Grossularite (enhances fertility)
Jade (assists fertility)
Thulite (enhances fertility)
Tektite (worn as a fertility talisman)

HTH's

Tanya