SB 9.9.35

yasmān me bhakṣitaḥ pāpa
 kāmārtāyāḥ patis tvayā
tavāpi mṛtyur ādhānād
 akṛta-prajña darśitaḥ
Word for word: 
yasmāt — because; me — my; bhakṣitaḥ — was eaten up; pāpa — O sinful one; kāma-ārtāyāḥ — of a woman very much bereaved because of sexual desire; patiḥ — husband; tvayā — by you; tava — your; api — also; mṛtyuḥ — death; ādhānāt — when you try to discharge semen in your wife; akṛta-prajña — O foolish rascal; darśitaḥ — this curse is placed upon you.
Translation: 
O foolish, sinful person, because you have eaten my husband when I was sexually inclined and desiring to have the seed of a child, I shall also see you die when you attempt to discharge semen in your wife. In other words, whenever you attempt to sexually unite with your wife, you shall die.