How Do You Stop Having Babies? (CK3)

To completely stop having children, you can become celibate through the learning lifestyle tree. This is generally the easiest option. Otherwise, you can divorce or assassinate your spouse.

Also, your chances of a pregnancy can be reduced by marrying old characters or waiting until your player character is older before marrying. Watch out for fertility modifying traits, too.

But why would you want to stop having children? One big reason is because reducing the number of children you have helps you control your succession with more precision. It can also avoid cluttering your game with many characters. This allows you to keep track of your children and give them a better education.

How Does Reproduction Work in CK3?

First, it’s useful to understand how pregnancies are calculated by the game.

The Basics

Each character begins with a base fertility rate according to their age and gender.

Women cannot normally reproduce after the age of 46, although some characters not connected to the player have been known to do so rarely.

Note: Women lose 5% fertility after every child. Concubines and other extra spouses have halved fertility.

Pregnancy chance is calculated every month according to this formula:

4.75 x (Male Fertility + Female Fertility) / 2

When calculating, percentages are converted into a whole number. So as an example, to calculate the pregnancy chance for a married couple who are both 33 years old, with no children, and no modifiers:

4.75 x (1 + 0.7) / 2 = 4.04% chance of pregnancy per month

Traits Affecting Fertility

The majority of traits that modify fertility are congenital. That is, they’re inherited or given at birth.

*If a character is barren or sterile, they might still be able to have children, even though the tooltip says they cannot.
**Melancholic has a non-congenital version too, which can be gained or removed by events.

There are two personality traits, one physical trait, and three lifestyle traits that modify fertility.

Most diseases and illnesses, like infirm or ill, reduce fertility at varying levels.

Also, some events and artifacts modify fertility too. Event modifiers are usually temporary, and artifacts can be equipped or unequipped at will.

How To Stop Having Children (Best Methods)

1. Become Celibate

Becoming celibate, if you can, is the best option with the most flexibility and no chance of having children.

You can unlock the option to become celibate by choosing the “Restraint” perk in the Learning Lifestyle tree. It will cost you at least 2000 Learning Lifestyle experience.

After selecting this perk, you can choose the “Embrace Celibacy” decision from the menu on the right. This choice is free.

You can reverse this decision at any time through the same menu. But if you want to abandon celibacy and then become celibate again later, you will have to wait for 12 months.

Note: If you have any of the reveler traits, you cannot use the “Embrace Celibacy” decision, even if you take the perk!

Reveler traits are obtained by hosting or attending feasts. You can get these traits within the first few feasts, so if you want to become celibate, you might want to avoid them.

Tip: If you become celibate and then get a reveler trait during your celibacy, you will remain celibate until you choose to abandon celibacy. Be careful, because you won’t be able to become celibate again once you do this.

2. Remove Your Spouse

Divorcing or killing your spouse will prevent you from having children with them.

You can still have children through events or lovers, but without a spouse they’ll be considered bastards and won’t inherit from you. Most of these events are in your control, but some are not, like those at feasts.

2a. Divorcing a Spouse

Divorcing is usually quick and easy, if you have the piety. Although it can be difficult to divorce your spouse depending on your religion.

To divorce your spouse, right click on their character portrait and find the “diplomacy” heading. Click on “more” to reveal the divorce action.

Catholic rulers have to pay piety and the pope must agree.

In some religions like Muwalladism, divorces are actually very easy, and might simply have a piety cost.

In a few minor religions, divorce is not permitted at all, like in Alevism.

2b. Assassinating a Spouse

Killing your spouse can take a bit longer and has a chance to fail. You might also face consequences for your actions.

To assassinate them, right click on their portrait and choose “murder” under “hostile.” This will begin a murder plot in the Intrigue tab on the right.

The murder plot takes time to complete and will offer you some events to increase (or decrease) your chances of success and secrecy. Recruiting agents will improve your chances.

Having a good intrigue skill and a few intrigue perks can help you with these plots as well.

There are a few possible consequences if you fail, including being outed as a murderer! This causes other characters’ opinions of you to drop and is punishable by your liege, if you have one.

Tip: If your spouse is able to fight in armies, you can assign them as a commander to an army and lead them into an impossible battle. If they die, you won’t be accused of murder!

3. Marry Old or Infertile Spouses

A marriage that includes an older character will produce fewer children due to reduced fertility. After the age of 46, women can’t become pregnant anymore either.

If you divorced or lost your spouse and don’t want any more children, marrying an old character will still give you spouse bonuses with reduced or no pregnancy risk.

Note: Male characters are fertile until death. If you play a female ruler under the age of 46, you can still become pregnant no matter how old your spouse is.

While arranging a marriage, you can choose to sort by fertility or infertility using the game’s menu, to make this process easier.

As shown in the “Traits” section of this guide, fertility is also modified by many traits in the game, not just age. Make sure your spouse has the type of traits you want.

If you still need children, but only a few, you can marry an older character who is still fertile. For example, a wife who is 35 years old could have children for the next 10 years.

Be aware that fertility is much lower at older ages and there’s a chance you won’t have any children at all. If you leave this until too late in the game, you might die without an heir.