أَو يُزَوِّجُهُم ذُكرانًا وَإِناثًا ۖ وَيَجعَلُ مَن يَشاءُ عَقيمًا ۚ إِنَّهُ عَليمٌ قَديرٌ

Or He combines them in pairs, male and female, and He renders whom He wills infertile. He is All-Knowing, Most Capable.