I have heard and read this a few times, and what is written below is sometimes advised to couples who are childless [or with other problems] as last advice often

Don’t look for “mathematic explanations”.

If someone happens to be in the presence of a situation [group, party or the like and arguments start between 2 people where someone publicly shames or even curse another [an absolute forbidden act of course!] and the one who is being ashamed is capable of not reacting on the insult[even if there is whatsoever no truth in the accusation] then the insulted person can directly afterwards bless a friend or whoever is present at the party and ask for a blessing commented to anything their heart is asking for, and the blessing may come through.

I have heard this in connection with couples who were childless for 10 or much longer and got blessed with a child after such a happening.,

One quoted example is where a woman at a party was cursed by another [wicked] woman in public, and before she could open her mouth another woman behind her whistled in her ears and begged her: “please, please don’t answer, don’t react, and she managed to keep quiet with a flush on her face from shame and directly afterwards the unknown woman behind her asked her to bless her with a child after 22 years of a childless marriage[and explaining to her why she begged her not to react!

Less than a year later she was blessed with a child![told by Rav Kanievsky]

This fact is connected with a passage described in the Talmud [see below]

  1. Talmud Bavli, Shabbos 88b
Our Rabbis taught: Those who are insulted but do not insult, hear themselves reviled without answering, act through love and rejoice in suffering, of them the Writ saith, But they who love Him are as the sun when he goeth forth in his might.תנו רבנן: עלובין ואינן עולבין, שומעין חרפתן ואינן משיבין, עושין מאהבה ושמחין ביסורין – עליהן הכתוב אומר הואהביו כצאת השמש בגברתו