Ah, I randomly stumbled upon a proof that in 1933, there was no drop in fertility rates in USSR
Taken from this
https://istmat.org/files/uploads/40054/rgae_1562.41.65_statisticheskie_dinamicheskie_ryady_1913-1951.pdf page 237 (213) for RSFSR. Ukraine has the same dynamics This is how many schools there were in RSFSP at this or that year, second row how many kids were in schools at this or that year total. Third row is kids at 5-10th grades.
So, in 1932-33 there supposed to be a big hunger that killed a lot of people and dropped fertility rates, but in 1940 we can see that there's no real drop in the number of schoolchildren (at 7-8 years old they go to school). Meanwhile, the fertility rate drop during the war RESULTED in the drop of the number of schoolkids (1940 + 7-8 - we can see low numbers of schoolkids). Second pic is fertility rates, the country with the highest drop is USSR, obviously
As we can see, secret documents from the archives DO NOT SUPPORT the reconstructions of fertility rates that show a sharp drop in fertility rates in 1932-33, meaning there was no noticeable hunger in 1932-1933