Then they went for 'assisted reproduction' (in-vitro fertilization [IVF]). The first implantation lasted for a couple months, then she miscarried. The later embryos didn't take (I think they tried 2 more IVF cycles, from the frozen embryos). Eventually they gave up and started getting ready for adoption.
I went over to their house last Mothers day. They put ultrasound pictures in the box to surprise my mom. A older female friend of mine says she's seen this happen all the time: give up on 'trying', and the pregnancy will appear.
My brother and sister-in-law don't really talk to me about medical things, and I don't tell them where they're off. But I think her IUD was the "chemical castration" variety (plastic with the levonorgestrel, brand name Mirena). I never told them, "you shouldn't have trusted the pharmaceutical-industrial complex to not take your fertility away prematurely", as it was too late for that.
Progestins are sold to women as hormones that regulate their menstrual cycles, but really they're imitation hormones that suppress the menstrual cycle. Most modern women don't want a dozen pregnancies, most modern men don't want a herd of children to take care of, so FDA-approved fake hormones are an easy sell. But if we're actually concerned about the trend line from hyper-fertile to sub-fertile, being honest with women about what's in their "birth control" prescriptions is a good start.
[I hereby take credit for the anonymous edit that fixed the introduction of the Wikipedia entry for Progestogen. The fix has persisted across the years. Many others have come along to reword the introduction. Someone inserted a clarification to my edit to say that fake-hormones are used in Medicine, but my word insertion and reference are still there :) https://en.wikipedia.org/wiki/Progestogen ]
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