Reproduction
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Reproduction is the means by which human babies are created.
Note: Due to the continuous nature of the subject matter, this page covers from conception to the age of three.
Acquisition
Babies can be obtained via several different methods:
- Choosing them as a starting colonist via the scenario system.
- Natural reproduction, through pregnancy.
- Assisted reproduction, through surrogacy or growth vats.
- Purchasing them from slavers.[Can babies be bought?]
- Receiving them from quests and events. Babies of any faction can be adopted instantly to the colony, without angering them.
Note that with the exception of the first point, these methods become unavailable if "Disable children" is toggled on in the storyteller settings.
Natural Reproduction
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Pawns have a chance to get pregnant when they initiate lovin'. Note that pawns must share a two-person bed, bedroll, or sleeping spot to initate lovin' but do not require one to avoid the "sleeping alone" mood debuff.
Chance
The prospective parents' chance of successfully reproducing is primarily controlled by their Fertility stat. The player has three options to adjust pregnancy rates from Lovin' in any relationship. By opening the social tab, to the right of a Lover, Fiancee, or Spouse, you can see a button that lets you change the couple's approach for having kids.
Normal (Default) | x1 pregnancy chance. | |
Avoid pregnancy | x0.25 pregnancy chance. | |
Try for baby | x4 pregnancy chance. |
Therefore, the total chance of pregnancy in one relationship is likely:
Pregnancy chance per relationship = Mother's fertility x Father's fertility x Reproductive Approach x Times Lovin' |
The actual chance that a pair of pawns will do Lovin' each night varies, but it requires them to share the same bed and sleep at the same time. Their chance of Lovin' varies by age, as seen in this chart. The low libido and high libido genes will also alter this. There have been reports that colonist mood and opinions of each other also influence the chance of doing Lovin'.
Pregnancy
Pregnancy lasts for 18 days, broken into three 6 day trimesters. The player will receive a notification when the pregnancy starts and when it progresses from one trimester to the next. The pregnant pawn will gain penalties to movement, manipulation, and hunger rate, increasing each trimester as seen in the chart below.
Stage | Effects |
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First trimester |
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Second trimester |
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Third trimester |
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Throughout their pregnancy, they will also occasionally gain mood buffs or debuffs due to hormonal induced mood swings.[Detail needed] They may also receive the "morning sickness" condition, which lasts 4 to 8 ingame hours.
Morning sickness:
- Consciousness: ×0.8
- Moving: ×0.9
- Manipulation: ×0.9
- Vomiting MTB: 1.8 Hours
Note that Pawns in the character selection menu can begin the game already pregnant.
It is impossible for a mother that is lactating to have another child under any circumstances, even via surrogacy.
Birth
The player will recieve one notification when the mother hits the third trimester: "<Colonist>'s baby prep", which explains all the steps you can take to help the mother give birth successfully. Besides preparing a location and doctor for the birth, this notification reminds you to prepare a food source for the baby and build them a crib. Labor will happen roughly 6 days after, starting with a notification of "<Colonist> in labor!".
Once labor begins, the birthing procedure can be initiated by clicking on the mother, and selecting the "Begin birth" option. This allows the player to select participants and a Doctor, much like Ideology's rituals. The procedure will take place at a bed or sleeping spot, chosen automatically (preferring medical beds) if the mother is not already in bed.
Labor
The progress of labor can be tracked in the mother's health tab. Labor begins with contractions, different stages of dilation that change randomly over time, with all adding various amounts of pain and restrictions on movement for the mother. Many stages will incapacitate her, so even before the childbirth operation begins, it is important to bring her to a bed. When the childbirth operation has proceeded for a while, you will receive a small notification saying "<mother>'s labor has entered the final stage", and the labor will progress to the final "pushing" stage.
Stages of labor:
- dilation, mild: pain +25%, moving x40%
- dilation, debilitating: pain +85%
- pushing: pain +85%
During childbirth, the spectating loved ones may socialize with each other, but the doctor and mother will be focused on their tasks. Spectators and the doctors can leave if needed. Finally, you can cancel the birth operation by selecting any of the involved pawns and then selecting the "Cancel child birth" option, which allows you to restart childbirth later.
Quality
This screen will show you the expected quality of the birth, determined by:
- Loved one present: the presence of someone that the mother considers a friend or more gives +5% quality, with no stacking for multiple friends or a better friend. By default, the father will be selected to be present. If the doctor performing the operation is a friend, they will count towards this bonus too.
- Age of the mother: a 22-year-old has a +50% quality, and as the mother grows older, this drops.
- Doctor's medical skill: can range from 0-20% or more. Skill level 1 gives 1.3%, 3 gives +3.8%, 7 gives +8.8%, and 16 gives +20% quality.
- Indoors: if inside, the quality gains +5%.
- Room cleanliness: cleanliness can range from 0-0.6, giving 0-10% in quality bonuses.
- Bed health effects: contributes up to 5%, with things like bed quality, a medical bed, and (perhaps vitals monitor or other furniture?) influencing this stat. A bed rating of 5 guarantees a quality bonus of +5%.
Therefore, the most important factors in a safe birth are the mother's age and the doctor's skill level. The expected duration of this operation is variable, but will end in the baby's birth or mother's death.
Birth quality is likely determined at the moment of the baby's birth; allowing the doctor or loved ones to leave, or having the room grow dirty, has an effect on birth quality.
Outcomes
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Depending on the quality, the baby can be born healthy or sickly, or they may die during birth. At lower qualities, there is also a chance that the mother can die during childbirth.
Expected Quality | 76 | 84 | 95 |
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Mother dies | 0.98% | 0.45% | 0% |
Still | 3.3% | 3% | 2.6% |
Sick | 7.4% | 7.5% | 7.5% |
Healthy | 89% | 90% | 90% |
You will receive a notification when the birth is complete, and the baby will appear on an adjacent tile. If the baby was born alive, a pawn with the Childcare work enabled can be instructed to either move the baby to a safe space, or to deliver it to the mother for breastfeeding. The baby will be born hungry, with a mood penalty of −6.
If your baby was healthy, the notification is "Healthy child birth", and it gives you 24 hours to choose a name for the baby. This is the only time where you can completely customize the baby's first and last names, and you additionally can add an optional nickname. The game will suggest the mother and father's last names on this screen, and provide random suggestions for the other names. Until then, the baby's name is temporary, and called "Baby <Mother's last name>". The baby will also receive the Childhood title "Newborn", and belong to the mother's faction. The baby's parents will receive a 15-day mood boost that "<Baby> was born healthy" +8.
If the baby is born sick, they are affected by a form of infant illness, which can start at a variable intensity. If left untreated before 10 days is up, the baby dies, but if it lives through 10 days after birth, the illness will no longer affect the baby. You will also get the chance to name your baby.
If the mother survived childbirth, she will remain in bed, incapacitated by exhaustion (Postpartum exhaustion) for 16 hours. She'll no longer feel any pain from childbirth, but won't be able to move. However, if another pawn delivers her baby to her, she can begin breastfeeding.
Lactation
Lactation is the mechanic that allows pawns to breastfeed babies. Lactation gives pawns a milk fullness stat, and when milk fullness is above 0%, a pawn can breastfeed any baby, even if it is not their own child. There are other consequences to lactation, however: lactating pawns require more nutrition per day, and they cannot become pregnant, regardless of their fertility and reproductive strategy. Lactation last indefinitely, only stopping after 10 days of not breastfeeding a child. You can view a pawn's lactation details in their Health panel.
Upon a successful childbirth, a mother will begin lactating, with milk fullness starting at 100%. Milk fullness regenerates at varying rates depending on the mother's food level. Lactating pawns require more nutrition per day in order to produce milk: the mother's Food Consumption stat rises from 1.6 to 2.1 nutrition per day, a gain of +0.5 (a simple meal has 0.9 nutrition). However, the nutrition used to make milk depends on the milk regeneration level, so a hungry lactating pawn won't require as much extra nutrition. You can view their current nutritional needs by checking the details of their "Lactating" condition in the pawn's Health tab. Lactating does not affect any other pawn stats or conditions.
Hunger Level | Ravenously Hungry | Hungry | Full |
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Milk Regeneration | 25% | ? | 100% |
Extra Nutrition Per Day | 0.13 | ? | 0.5 |
Assisted reproduction
After Fertility Procedures has been researched, an ovum can be extracted from a fertile female pawn, be they colonist, prisoner, or slave,. It may then fertilized by a fertile male colonist or slave (but not prisoner) to produce an embryo. The resulting embryo can then be implanted in female pawns (may be prisoner, colonist, or slave) to initiate a pregnancy, placed in a growth vat, or sold.
Surrogacy
With the Fertillity Procedures research, you can create and fertilize embryos. They can then be implanted into a pawn for a chance to become pregnant. The chance of success depends on the surrogate's own Fertility.
Embryos can be created from 2 pawns with any Fertility above 0%. Even if they did not supply the ovum, the surrogate will be considered the birth mother. Otherwise, it will act as a regular pregnancy.[Verify].
Growth vats
Growth vats are a complete alternative to pregnancy. They require the Growth vats research to make, as well as Fertility Procedures and 2 pawns with > 0% Fertility to actually create embryos.
They allow an embryo to be born in 9 days, half the time of a natural pregnancy. Active vats must be given a constant supply of 200 W of power and 6 nutrition per day - or around 6.5 simple meals per day - to ensure survival of the fetus. If lacking either, then the fetus will undergo biostarvation, increasing by 50% per day. If biostarvation reaches 100%, the fetus will be destroyed.
Growth vat births always have a quality of 70%, which affects the chance of the baby being born healthy. As it avoids natural birth, the mother won't be weighed down, and there is no risk of them dying.
Heredity
When an embryo is conceived, it will inherit some of the genes of both parents. During a mother's pregnancy, you can view her child's genes by going to her Health tab and selecting the information button for her pregnancy. The genetics section will list all genes that her child has inherited.
Genes which can be passed down come from the germline DNA, and are called endogenes. Pawns may modify themselves with xenogenes, but as it's not part of a pawn's germline DNA, it cannot be passed down. If an endogene is only present in one parent, it has a small chance to be passed down.[What's the chance?] However if an endogene is present in both parents, it will always be passed down.
Generally, all pawns will have at least one hair color and skin color endogene. Offspring will always pick one hair color and skin color endogene from their parents. If no hair/skin color endogene can be found in either parent, such as if they were two highmates, a random hair/skin color endogene will be picked from the natural list of hair/skin colors instead.
If a pawn has multiple cosmetic genes within a category, like body type, one random gene will override the others. This will be the gene represented on the pawn. For non-cosmetic genes within a category there is a fixed priority for overrides, usually favored towards the negative variations. For example, an awful shooting aptitude will override all other shooting aptitudes. Xenogenes will always take priority over endogenes. Thus, even though the Slow runner endogene overrides their Fast runner endogene, the Fast runner xenogene will override the Slow runner endogene. Note that overridden endogenes can still be passed down as normal.
If a child is born from an incestuous relationship, there's a risk of them becoming inbred; up to 80% for direct relatives. [Which relations?]
Inbred |
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Fertility
Fertility is the main pawn stat and is a percentage multiplier on pregnancy chances. Pregnancy chance is dependent on the fertility of both partners. Fertility affects more than just the chance of a natural pregnancy, it affects all types of reproduction. It also affects the chance of successfully implanting an embryo in a surrogate, and sterility prevents both the extraction and fertilization of ova for IVF.
This stat is affected by a variety of factors, such as age and genes. For baseline humans without fertility-modifying genes, both men and women start becoming fertile after age 14; women's fertility increases until it reaches 100% through ages 20-28, then drops steadily from 100% to 0% at age 50, while men's fertility increases until it reaches 100% through ages 18-50, then starts dropping before reaching 0% at age 90. Fertility is also affected by contraceptives and genes. The Fertile gene doubles fertility and the Sterile gene completely nullifies it.
Regardless of fertility, a pawn must be at least 16 in order to participate in reproduction.
Female Fertility |
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Male Fertility |
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Contraceptives
The simplest way in the game to prevent pregnancy is to not give pawns a double bed to themselves. However, it deprives them of the mood bonuses of Lovin' in the first place. You can set pairs to avoid pregnancy in the Social tab, which reduces the rate by -75%. If a pawn is lactating (from having given birth before), then it is impossible for them to have a child under any circumstances.
The Fertility Procedures research gives access to multiple ways to stop pregnancy. These surgeries can be applied to any pawn age 16 and up, and can be performed even if the pawn is already infertile.
IUD
You can stop a female pawn from becoming pregnant with the "Implant IUD" operation. It lasts indefinitely, with the operation requiring 1 Medicine. You can later remove it through the "Remove IUD" medical operation, also for and 1 Medicine. Women may embark with IUDs already implanted. If either of these operations is botched, the patient will become permanently sterile.
IUDs also stop pregnancies in the first trimester.
Vasectomy
You can stop a male pawn from impregnating others with the "Perform vasectomy" operation. It lasts indefinitely, with the operation requiring 1 Medicine. You can later remove it through the "Reverse vasectomy" medical operation, also for and 1 Medicine. Men may embark with the operation already performed.[Verify] If either of these operations is botched, the patient will become permanently sterile.
Tubal Ligation
This permanently stops a female pawn from being able to reproduce. "Perform tubal ligation" is a medical operation requiring 1 Medicine of any type.
Termination
If the pawn has already become pregnant past the first trimester, the only option left is to terminate the pregnancy. This can be achieved through the medical operation "Terminate pregnancy" requiring 1 Medicine after which the pawn will no longer be pregnant.
This operation will upset the affected pawn. Depending on the trimester of the pregnancy, a moodlet of −5 for the first, −10 for the second, and −20 for the third will occur, lasting for 10 days.
Babies
The end result of pregnancy is a human baby. Babies are small, helpless creatures that cannot walk or do anything by themselves. They only have three basic needs: food, sleep, and play.
Under the default storyteller settings, pawns under 13 will age 4x faster than normal. Growth vats can speed up a baby's growth by 20x that of an adult, or 5x faster than default. Using a growth vat seems to have no ill effects on a baby or its development, at least until it exits the baby stage.[Not thoroughly tested] However, parents gain a −4 My baby is in a growth vat moodlet.
If a baby is left on the ground, any colonist (even those incapable of childcare or hauling) can try to bring the baby somewhere safe, like an available crib. Usually a colonist will quickly try to do this automatically. If you draft a colonist while they are carrying a baby, you'll receive a pop-up warning that your colonist is carrying a baby while drafted. If you undraft and redraft the colonist, they will drop the baby.
Food
Babies need less nutrition to become full, but their hunger rate is adjusted with it to require food twice a day. Since babies cannot eat anything by themselves, pawns assigned to childcare will help feed them. The feeding process is fairly slow when compared to adult eating.
They can only be fed in one of following ways:
- Breastfeeding from any lactating pawn, even those not their mother.
- Cooking and feeding them baby food from vegetable ingredients.
- Feeding them animal milk or insect jelly.
Of these, breastfeeding is usually the easiest. Unlike other foods, which feed in bursts only once the food has been consumed, breastfeeding will gradually increase the food bar. This allows the breastfeeding pawn to pause at any point, whilst also not wasting excess food.
You can control what foods the baby can eat and who will try to feed the baby in the baby's "Feeding" tab. By default, the mother will be set to Urgent, with all other pawns set to Childcare. If a pawn is set to childcare, that does not mean they will feed the baby: their childcare labor may be turned off, or they may be incapable of it.
- "Urgent" means the pawn will feed the baby day or night, even if the pawn is not assigned to childcare or capable of it.
- "Childcare" means the pawn will feed the baby as childcare work.
- "Never" means the pawn won't automatically feed the baby.
You can allow the baby to eat milk, insect jelly, and baby food in this tab, but can't control breastfeeding here.
Mood
Babies' moods are influenced by their needs for food, sleep, and play. These are affected at the same rates as for adults:
Hunger | Ravenously Hungry | Hungry | Normal |
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Mood effect | -12 | -6 | 0 |
At the highest level of play, babies receive a "Very Entertained" +10 mood boost.
Babies have the same expectations for colony life as most other pawns do, influencing their moods at the same rate. They also get a mood bonus when both parents are happy: "Parent is happy" +6. They appreciate comfort, with an excellent crib providing a +4 mood boost when they are resting.
Being held or breastfed does not affect the baby or adult's mood in any way. The only need breastfeeding influences is the baby's Hunger need.
Sleep
Unlike adults, babies don't follow a sleep schedule, instead falling asleep mostly at random. A crib should be provided for them to sleep in, as it will negate the negative mood from sleeping on the floor. A good quality crib will even increase the mood of the baby. Force-feeding or playing will wake them up, possibly keeping them unhappy from being tired.
Play
Babies need to be played with, in place of standard Recreation. An adult assigned to child care will play with the baby once the play need is almost empty. There are different activities that will fulfill the baby's play need. A toy box and baby decoration increases the quality of play.
Giggling and crying
Instead of mental inspirations or mental breaks, babies will have giggling or crying "fits" which gives a mood boost or penalty to other colonists within a 10 tile[Verify] radius. The ratio between giggling and crying is directly related with the baby's mood.
Mood boosts from giggling babies go from +4 up to +10, while crying babies can cause mood maluses from −8 down to −20. Parents are only half as bothered by their baby crying, and twice as happy when their baby is giggling.
Giggling occurance |
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Crying occurance |
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Giggling to crying ratio (higher is better) |
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