Taking aside all of your emotional concerns, you should know right away that women absolutely can have healthy biological children at or past the age of 39. Obviously I can't speak for your wife and her specific health or reproductive situation but in general, the idea that "the window has closed" is more often than not totally false. Look into this in more detail with real medical professionals. One interesting observation comes from the article I link to below, which points out that many of the supposed female fertility window statistics are actually based on extremely old information from pre-modern times. Worth reading for a bit of optimism and perspective.
https://www.theatlantic.com/magazine/archive/2013/07/how-lon...
noteworthy quote from the article:
"The widely cited statistic that one in three women ages 35 to 39 will not be pregnant after a year of trying, for instance, is based on an article published in 2004 in the journal Human Reproduction. Rarely mentioned is the source of the data: French birth records from 1670 to 1830. The chance of remaining childless—30 percent—was also calculated based on historical populations.
In other words, millions of women are being told when to get pregnant based on statistics from a time before electricity, antibiotics, or fertility treatment."