Muslims answer only please!!?

my muslim sister wants to have a baby but cant coz of her age she is muslim and married to a muslim.. i am not muslim but my husband is muslim.. is it allowed in the qu'ran for a women to allow her husband to impregnate another women with his own sperm without being in contact with the other womens body ie. sperm insemination. my sister and i would like to try this but she is worried that it might be haram.. please refrain from any hurtful or judgemental remarks thank you