Steady Pregnancy Progression (Preview)
09.10.2026 UPDATE: Added the French, Spanish and Brazilian Portuguese translation links
27.09.2026 UPDATE: The mod is updated to the 1.1.1 version! Remove the old files (you can keep the settings) and reinstall the mod!
Just small recalculations in a couple of code parts to make everything coherent
Fixed minor mistake in Russian translation of min duration input dialog ('максимальная' -> 'минимальная')
I remade my old mod, that changes the pregnancy belly size depending on the offspring count. This remake still provides this feature, but not only that!
Daily Changes
You know that belly of pregnant Sims changes only with the trimester, and that doesn't look smoothly at all. But with this mod the belly size changes every day steadily! It updates at 4 AM to not draw your attention. It works for all Sims in the save, both played and NPCs.
By default, it even includes the hidden pregnancy period, so you will be able to notice pregnancy visually on early stage.
And the old feature is still here: the belly is bigger if your Sim carries more babies ;)
Each Pregnancy Unique
No more predefined pregnancy length for all Sims. This mod set unique length on every pregnancy individually. Basic value is between 87.5% and 112.5% of the original basic length (which you can also change via MCCC or Wicked Whims). But this range is applied only in cases of one baby. The more babies your Sim carries, the lower will be the length range – so, the shorter pregnancy will be.
Of course, for one Sim with one baby pregnancy can be shorter than for another Sim with two babies, as it's all about probability.
Constant Belly Size
In my previous mod, the size could be reset in some cases. In this mod it's always the same, because I rewrote the belly size function directly, even while posing for photos and in CAS.
The cheat 'Update pregnant belly size' on the Sim is still available, but it's for very specific cases I actually can't think of (because it should work normally anyway).
Full Customization
I provide several templates of belly size on each trimester for various count of babies, they have the same values as the versions of my old mod. But now it's a preset, which you can adjust as you want!
Adjust Settings
From the 1.1 version, with testingcheats enabled you can Shift + click on a Sim (teens and up) and find the settings interaction in the Steady Pregnancy Progression category.
Here you can disable / enable progression in hidden period (enabled by default), adjust belly size and pregnancy duration range depending on the number of babies, and reset the settings (to the base template).
Belly Size Settings
You can adjust belly size in each trimester + in labor for one, two, three and more than three babies. Start from the first trimester to in labor, because each next stage must have value no less than the previous one.
So you can experiment with values and set up your perfect template ;)
WARNING! You should toggle trimester back and forth, if you want to change the size during current pregnancy. You can do that with the MCCC Pregnancy cheats, for example.
Pregnancy Duration Settings
You can also set up min and max duration adjusting the coefficients, they must be between float numbers between 0.1 and 5.
Say, your base pregnancy duration (you can do that with MCCC or WW) is 12 days. It actually considers only three trimesters, while with hidden and in labor period the total length is 25% longer, so the total base duration is 16 days. If you set the min coefficient to 0.8 and the max coefficient to 1.2 for one baby, then total duration for a Sim will be randomly chosen from ~13 days to 19 days. Of course, it varies for each Sim individually.
You can just input a coefficient here, and all calculations of length will be updated, so it helps you to find the most suitable value.
WARNING! The duration settings update will affect only next pregnancies, otherwise it would be a mess.
Compatibility
Just as it was before, it's compatible with MCCC by Deaderpool, Wonderful / Wicked Whims (18+) by Turbodriver, Relationship & Pregnancy Overhaul by Lumpinou, Realistic Childbirth by Pandasama and other pregnancy mods that don't override the belly size. It follows that you can have only one mod that affect belly size in the Mods folder.
Also, if you want a smooth pregnancy progression, you should set a long enough length of pregnancy (it can be made by Wicked Whims or MCCC). The default length is 3 days (one day per trimester) + one day of hidden pregnancy. The hidden pregnancy duration isn't included in the total length, but keep in mind that it lasts as one trimester.
On the default length the belly size progression equals the trimester progression, so you won't see changes. Set at least 6 days or more – then it will be even more smoothly. My pregnancy length setting is 81 day ;D
Check the compatibility status HERE
REQUIRED
Base Game Compatible
CONFLICTS
With mods that change the belly size, and read the compatibility section for the details
TRANSLATION
Russian by me
Spanish translation link by JA Simmer
Brazilian Portuguese translation link by Day MrsRaposo
French translation link by Luniversims
INSTALLATION
The newest mod version is 1.1.1, reinstall the mod! You can keep your settings, they will be updated
Put in the Mods folder no deeper than one subfolder AND choose a belly size preset!
PRESETS FOLDER (CHOOSE ONLY ONE)
Don't delete the JSON data file!
IF YOU USE RPO BY LUMPINOU:
You need BOTH EA injector (i put it in the mod archive) and my special injector for supporting this mod. Take it HERE
F.A.Q.
No changes, no belly?
You have a conflict
You didn't install Lot51 Core Library
You placed the mod deeper than one subfolder
Pregnancy length is quite long and you just didn't notice progression
It's a hidden pregnancy yet and you turned off the progression on this period
You deleted the JSON file
You play with RPO but haven't installed the compatibility injector
No cheats?
You installed Lot51 Core Library incorrectly
Sim is not pregnant
How to adjust the settings?
Read the Full Customization section
Settings were reset?
You didn't have a settings file in the same folder
A file had incorrect values
Well you basically reset it in the settings menu
Belly disappeared?
You're on the 1.0 version and you enter the game with the mod for a first time, and a Sim has a paused pregnancy. Toggle the trimester by the MCCC cheats, and get the updated mod to prevent it in future
Pregnancy duration of this Sim hasn't changed after adjusting the settings?
The updated settings will affect only next pregnancies
Is EA Injector required when using RPO?
Yes, you need both injectors
Let me know if something went wrong!
DOWNLOAD
HERE (21.08 in Public)
RPO Compatibility Injector HERE (but don't delete EA injector)
I can only help if you provide me with the details of any issues you are experiencing – so 'It doesn't work' won't help at all. Read THIS before writing a bug report (via the link below, not in the comments section). And please read the FAQ section!
Contact me | Buy me a Coffee | Bug Report | Mod Status Sheet
Comments (59)
Thank you for this very immersive mod ! About the belly size setting, is the number we put in the size at the start of the trimester or at the end ?
You're welcome! That's the start value
does this conflict with any lumpinou or pandasama childbirth mods?
No, please read the conflicts section
Hiii! Hello, I just have one tiny question and I'll be out of your way. does this mod conflict with the pregnancy overhaul by littlemssam?
Hi! No, it doesn't. Just don't install the belly size module
Thank you for this - Here in Spanish (free) - https://www.patreon.com/JASimmer1/posts/traduccion-al-de-170672764?utm_medium=clipboard_copy&utm_source=copyLink&utm_campaign=postshare_creator&utm_content=join_link
Muchas gracias! Eres la mejor 🧚🏻♀️
Psylocke's Early Pregnancy Quirks seems to be conflicting with this mod, specifically their ww compatible version. My save isn't loading when I have both in at the same time. If there's a fix/some way to make them compatible that would be amazing because I really want to use both. Not sure which mod that would have to go through (deleted my last comment because I thought I fixed the problem, it does not seem that I have)
Hi, no conflicts as expected, I just tested it. Your save isn't loading because you have broken / outdated scripts or you didn't install the requirements correctly (some mods require Custom Preferences, but many players keep several versions of this mod). You never investigate an issue moving away one mod or two, but rather re-read installation requirements, test without any mods and make 50 / 50 if that's not the save issue. That's because often you can just forget what you have put in the Mods folder or miss that a modder placed a file you already have and so on
Hello where do you put oreset for belly as no folder I am not sure where this goes
Hi, it goes into the same folder where the mod is
Hi I wonder if you might be able to help me? I'm unsure how to fix this, but one of my teen sims accidentally got pregnant and she just ballooned out to the size of 3rd trimester/active labor. This issue sort of goes away when I remove wicked whims from my mod folder, but the pregnancy progression itself doesn't actually apply to teens for whatever reason (nor beforehand). I have the compatibility mods despite not having the pregnancy part of RPO, I have mccc, but I don't think I have anything else in my small modlist that would affect the teen mesh. Other than teens, it works flawlessly on YA and older sims and I love it.
I am so glad I found this bumps used to show for me with teens using just WW but an update or patch seems to have changed that and mccc setting look scary lol so the fact there is a mod just for bumps? Had me running aha canny wait to give it a spin
Hi! I translated the mod in french, it's available (for free) on my Patreon. Feel free to add it to your post
Hi there. Does pausing a pregnancy have any impact on the mod?
Hi, when the pregnancy is paused, my mod won't affect it. So it's always safe to pause and resume
I'm not sure if the problem is this mod or what. My pregnancy duration is 9 days (set from WW) Two of my sims are on first trimester, third is not showing. However, the pregnancy duration isn't nowhere near 12, nor 9 days, not even 6 days, it's about 3 days! From Sunday to Tuesday. Mod description says that the duration variation change would affect only next pregnancy, but I can confirm that it does follows the belly (and duration variation already). However, it doesn't follow the already set 9 days lenght! It's like the "hours" are three times faster than anyone else hours! Could someone confirm this time speeder "bug", by first setting pregnancy length to 9 days, then get two sims pregnant (to check if there's variation), and ONLY THEN apply this mod to mod folder, with default EA belly size json file, to check if the time is reset from 9 days to 3?
I don't know why you're referring to someone if I'm an active modder and answering the questions here. I made just the same actions: 1. set WW duration to 9 days 2. made two pregnant sims in the first trimester 3. exited the game, installed the mod with the default data 4. relaunched the game Both of them have 3 days per trimester. In the mod description I talk about changes after adjusting the duration settings, they will affect only new pregnancies. But the mod affects current pregnancies too once it's installed. I can't say what exactly happens in your game, as I haven't seen the logs nor the mod and WW settings
Belly Size Settings may be I dont realise prorotions or stuped in maths but from 0 to 1 included 0,54 can't change or lower i tryed without pregnacy - helpful but sixes are pritty good if to i wil set up settinds attentively((
Which trimester you're trying to adjust? What exactly happens when you're inputting the value? I mean, you can't set it up in random order. You must start from first trimester and go to labor step by step. It's required because belly suze on each stage can't be lower than on the previous one. If you mean it doesn't affect current pregnancy, that's because the changes are applied on the next trimester. If you want to see them right now, just toggle trimester back and forward using MCCC
Is a separate mod needed to extend the length of the pregnancy (like setting it as 2 days each trimester instead of 1, for example), or will adjusting the duration values do that? From what I can tell from your description, it looks like a separate mod is needed to change the length, but I just wanted to be certain that I'm doing it right. Thank you!
You need a separate mod like Wicked / Wonderful Whims or MCCC. The duration settings set range of chosen duration for a specific Sim relatively to the base duration value
I had downloaded and it’s not working for me
Please read FAQ
How do you use it?
What do you mean? A general description of usage in the post, do you have a specific question?
Please, pay attention to the compatibility injector for RPO! If you don't install it having RPO, belly just disappears
Hi!! Is it compatible with responsible pregnancy by Kemzima? Integration with her mods would be awesome!! thank you so much!!
Hi, thank you too! It's compatible, as well as with other interactions about pregnancy. The only limitation is for mods that change the belly size
Hi SonozakiSisters , French Translation for your mod^^ http://www.simfileshare.net/download/6239156/
Is there any way for people (like me) who know nothing about computer codes and pre-empting conflicts? I acn just put things together and see if they work in game but that seems rather haphazard. I was specifically thinking onf Responsible Pregnancy by Kemzima. I wouldn't know what strings are....or how to find them....or really what they are unless it's literally lines of codes as....processes = 1 string
I don't think you can figure it out without knowledge how to make mods, so it's always better to check the mod description and ask creators themselves. As for the mentioned mod, they have no conflicts, because the mod by Kemzima doesn't interfere with the pregnancy duration and belly settings
This will be going in my game as soon as it becomes public. I'm so excited only a week away from this Friday.
When will this be public?
On 21th August
If I use RPO mod should I only use that injector ? or will i need any other injectors
You need both injectors, that's why I included the main one in the mod archive
I mentioned this before, but are you able make the belly bigger than the base game maximum settings like this mod version two? modthesims.info/d/664109/pregnancy-variations.html
This mod doesn't make the belly bigger than the game allows at max, you can just make it bigger than the game sets it on each trimester. And you can do that with my mod too
Do you stop breast growth? I always looked for this...
No, because both sliders are included in the pregnancy progress. Brest growths steadily just as belly, though
At least I know I’m not the only one. I have my pregnancies set to 84 days 😭
Okay I might be a little slow but are you willing to make a video on this? This was a lot of words for elmo and I'm a visual learner 😂🫠 I am also VERY excited for this cause it makes waaay more sense then the big bellies we get in the game 😊🤓
Thanks! I'm planning to start making shorts for TikTok with the gameplay walkthrough, but not in the nearest future as I haven't done anything like that before
What's the length range for multiple pregnancies?
Depends on the number of babies, from 70% to 95% approximately. Though, I'm working on the update which let you adjust the settings in the game, including variety of length 🤗
How does it behave when you have pregnancy paused via MCCC?
It doesn't progress too, so you can pause it without any problems
This looks absolutely amazing! I've been wanting something like this for ages. 💝
Thank you! Me too, and finally I had enough time to finish this update
This looks very good! I really like the pregnancy progress mod you made before and this one looks even better! Thanks!
Thank you too!
🔥 Incredible. Love that it works with RPO too.
Yeah, it was essential for me as I always play with RPO
This is amazing, thank you so much!
You're welcome!
Can't wait until its public ! (> __ < )
I hope you love it once it's in public 🙏