If Violated Heroine is often crowned as the gold standard of pregnancy mechanics, then I shall make the bold claim that this game is as close as it can get to reaching that standard.
Does it have a good story? No. It is essentially the tried-and-true trope of yet another government mandated system. This time, it is due to sudden mass infertility disease that has rendered most men and women infertile, so it is up to you, one of the fertile few to help do your duty to the world to help repopulate the world. However, there is some variety here since you aren't forced to get knocked up, just highly encouraged to do so with lots of monetary incentives by the state.
Does it have good music? No. It is mostly default RPGMaker tunes.
What it is good at above all else, is the execution of the kink. It does not do so through elaborate scenes filled with dialogue, nor stellar animation, or even through battle-fuck systems ala VH or Vitamin Quest. Instead, it does so through its strong core mechanic that revolves around the pregnancy kink.
You have menstrual cycles, aphrosidiacs, fertility drugs, forced ovulation drugs, birth control, pregnancy tests, actual bodily changes induced by pregnancy and birth. Hell, it even has an OB/GYN clinic that you can go to for have checkups, have ultrasounds to figure out the gender of your kids and even how much they probably weigh to determine fetus health.
True, it does sound like what some users here call a 'pregnancy sim' or 'woman sim' since, aside from prostituting, working at a cafe or pimping out your apartment and paying rent, that really is all to it. However, the standing CGs are amazing since they not only show the darkening of nipples and growth of the belly with each progressive trimester, it even has X-rays that show the fetus(es) growing from zygote to full-term. The growth of the belly is also affected by the number of fetuses present and also if the baby/babies are overdue.
Yes, you heard me right: fetuses. This to me is what makes this game stand out from the rest since it not only portrays multiples but the mechanics are evidently made to appeal to that aspect. VH and VQ might have better overall kudos for gameplay but they don't have multiples. Granted, they have their own aspects that make them shine. Some games like Accidental Woman or the popular Fenoxo lineup do have portrayals of a multiple pregnancy but they lack the focus that Hazumi has.
More importantly, this game has full mod support from the devs and there are an impressive list of mods that you can add-on to the game available on here to further enhance your enjoyment. Or make your own if you have the know-how!
Hence, as a self-professed connoisseur of the impregnation/pregnancy kink, I highly recommend this game. In a sea of cheap buggy RPGMaker schlock and ghoulish 3D-render games that simply slap the pregnancy tag, this definitely stands out above the rest.
Of course, if you aren't into the kink or aren't exactly that into it, then don't. There is only one ending (that I know of) and the new game+ is essentially the same gameplay loop but with carried over stats and money along with a higher requirement to end the game (cough up dough to care for the kid yourself instead of handing them over to the state for mandatory adoption).