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

Children can be obtained via several different methods:

  1. Naturally, through pregnancy or surrogacy.
  2. Artificially, through growth vats.
  3. Purchasing them from slavers.[Can babies be bought?]
  4. Receiving them from quests and events.

Pregnancy methods

Female pawns can be generated pregnant. Other than that:

Natural

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 >0 Fertility. Even if they did not supply the ovum, the surrogate will be considered the birth mother. Otherwise, it will act as a regular pregnancy.[Check]

Growth vats

Growth vats are a complete alternative to pregnancy. They require the Growth vats research to make, as well as the 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 - to ensure survival of the fetus.

As it avoids natural birth, the mother won't be weighed down, and there is no risk of death. However, it also deprives pawns of the natural joys, or moodlets, of birth.


Reproduction

Natural pregnancy

Pawns have a chance to get pregnant when they initiate lovin'. The prospective parents' chance of successfully reproducing is primarily controlled by their Fertility stat. The odds can be further altered by choosing to "try for pregnancy" (x4 chance) or "try avoid pregnancy" (x0.25 chance) in a pawn's social tab.

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 lasts for 18 days, broken into three 6 day trimesters. The pregnant pawn will gain penalties to movement, manipulation, and hunger rate, increasing each trimester as seen in the chart below.

Stage Effects
First trimester
  • Hunger rate offset: +10%
Second trimester
Third trimester

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:

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 1 notification when the mother hits the third trimester. Labor will happen roughly 6 days after,

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. Presence of loved ones and a skilled doctor increase chance of a healthy birth. They will gather at a bed or equivalent. The quality of the procedure affects the probability that the baby will be born healthy, and can be improved by the presence of a skilled doctor and a loved one of the mother. The procedure will take place at a bed or sleeping spot, chosen automatically (preferring medical beds) if the player did not choose a bed themselves by starting the procedure via one.

The progress of labor can be tracked in the mother's health tab. Each successive stage of labor results in an increasing amount of pain, quickly incapacitating the pawn. Once birth is complete, the baby will appear on an adjacent tile, and the mother will be incapacitated by exhaustion for up to a full day. At this point, 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.

Outcomes

The baby can be born healthy, sickly, or die during birth. There is also a chance that the mother can die during childbirth. This is impacted by the quality of the room, the cleanliness, the quality of the bed, the quality of the doctor and if loved ones are around. The baby's first and last names can be changed within 1 game-day of birth, though nickname can always be changed.

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.

Pawns that successfully give birth (regardless if healthy or sick) then lactate and can feed their child milk. After 10 days of not breastfeeding a child, they cease to lactate.

Assisted Reproductive Techniques

After Fertility Procedures has been researched, an ovum can be extracted from a fertile female pawn, be they colonist, slaveContent added by the Ideology DLC, or prisoner. It may then fertilized by a fertile male colonist or slave only 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

A female pawn (who does not have to be the donor of the ovum) may be implanted with a fertilized embryo, giving the pawn a chance to become pregnant. The chance of success depends on the surrogate's own fertility.

Whether or not the pregnant mother is the one who supplied the ovum, they will be considered the child's birth mother.

The pregnancy is largely the same as a natural pregnancy. [Not thoroughly checked, quick devmode run to write this section].

Growth Vats

Growth vats are an alternative to Surrogacy, allowing an embryo to be born in 9 days, half the time of a natural pregnancy. Active vats must be supplied with nutrition and power, consuming 6 nutrition per day. If the vat lacks either, the fetus will start to suffer from biostarvation. Biostarvation increases by 50%[Verify?] per day while the vat lacks power or nutrition, and will gradually reduce otherwise; 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.

Post-birth, child growth can continue to be accelerated inside the growth vat up and until a pawn turns 18. However, they will not accrue progress on growth tiers whilst inside, leading to fewer passions and more limited choices for traits.

Children in grown vats age 20x as fast as normal children.


Romantic Relationships

Female pawns can begin a natural pregnancy after Lovin' a male partner (a lover, fiance, or husband). This makes a pawn's relationship status the primary factor in whether they will get pregnant soon. Players may help start romantic relationships in multiple direct, and indirect, ways. However, players don't have an easy control for breaking off a relationship.

Romance Controls

For any pawns over 16, the Social tab will have a "Romance..." button that allows the player to try instigating a romantic relationship between that pawn and another of the gender they're attracted to. This can be tried every 12 days, and can be done even when the pawns are already in relationships. You can only attempt to romance a target pawn that has a high-enough opinion of the current pawn and isn't closely related to them. Beyond this, their relationship and relative ages affect the Romance abilities chance of success.

Limitations

When you've selected the current pawn and attempt to Romance a target pawn, it won't be allowed if:

  • the target pawn has a negative opinion of the current pawn (stating "low opinion")
  • the likelihood of success is too low (stating "zero chance")
  • they are already in a relationship (stating something like "already Pawn's lover")
  • they are closely related (incestuous)

Pawns that are under 16 or have an incompatible sexual attraction will not even be shown on the dropdown list of potential Romance... targets.

Likelihood of success

With the current pawn selected, and the social tab open, you can see the chance of a Romance action's success by mousing over the target pawn's row in the social tab. It will tell you the probability of success and how it is calculated. The factors are:

  • the target's opinion of the current pawn
  • the pawns' relative ages (which additionally factors in each pawn's youth)
  • certain genes and traits for the pawns
  • the target pawn's opinions of the people they already are in relationships with

The current pawn's beauty traits are major factors in the chance of success, beyond their influence on social opinions. An Ugly pawn (Beauty -1.0) has a x30% multiplier on success. A Pretty pawn (Beauty +1.0) has a x230% multiplier on success. Beauty here can be influenced by normal Beauty traits or Beauty-affecting genes. The beauty of the target pawn does not provide a multiplier or affect these chances: there is no boost from a pretty pawn romancing a pretty pawn and no extra penalty for an ugly pawn romancing a pretty pawn.

Other genes can come into play as well. Someone with the Furskin gene has a x20% multiplier on romancing someone without it, and vice versa.

Note on relative ages The relative age factor doesn't just take into account the difference in age between colonists. It also factors in how old each colonist is. This effect is very large for young colonists. A 16 year-old's relative age factor with any colonist, of any age, will steadily increase from 0% to a maximum of about 25% as they age from 16 to 17 biological years. This factor is still affected by the other colonist's age as well: a late 16-year-old has a x4.4% multiplier on a relationship with a 46-year-old but a x4.1% multiplier with a 51-year-old. However, this is drastically outweighed by the youth effect, because that same 16-year-old only has a ~1% multiplier on their romance chance with a younger 16-year-old.

Relative Age maximum by pawn age

Once a colonist has reached the point where relative age isn't affected by their own youth, relative age is more affected by the difference in colonist ages.

Relative Age multiplier by age of male partner for a 22-year-old female

Indirect Relationship Controls

Starting and strengthening relationships

If you have the Royalty expansion, you can use abilities to increase a pawn's opinions of another, making it very likely that they will hook up soon if they run into each other enough and they keep trying to romance each other.

Breaking up relationships

You can try to decrease pawn's happiness and their opinions of each other to push them to break off their relationship. Another method is have one of them start an affair, when the other is in an ideology that doesn't condone free loving, to cause relationship harm.

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.

Female Fertility
Male Fertility

Chances of Natural Pregnancy

The chance of a female pawn getting pregnant is affected by how often they do Lovin' with male pawns, and how fertile the pawns involved in the Lovin' are. The base chance for pregnancy after Lovin' can be seen by multiplying each pawn's fertility stats together. You can find this stat in the pawns' info panel, in the Stats>>Basics section. Beyond this, the player can set baby controls for each relationship, preferencing a higher or lower chance of pregnancy. Finally, the rate at which different couples do Lovin' varies drastically, and the player has some control over this.

Therefore, the total chance of pregnancy in one relationship is likely:

pregnancy chance per relationship = pawn A's fertility x pawn B's fertility x baby strategy x times Lovin'

A given pawn's total chance of pregnancy over time can be found by adding their chance of pregnancy across each relationship they are in.

The actual chance that a pair of pawns will do Lovin' each night varies by several factors. If they're in the same bed and sleep at the same time, their chance of Lovin' varies by age, as seen in this chart. Additionally, their chances are affected by their libidos, which can be altered from the default by the low libido and high libido genes. There have been reports that colonist mood and opinions of each other also influence the chance of doing Lovin'.

Baby Controls

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 strategy for having kids.

By default, it is a hollow heart, with no preference for any pregnancy outcomes, and no affect on fertility.

If you change it to the sperm symbol, making the couple try for kids, their chance of pregnancy will be four times higher.

If you change it to the ban symbol, they will avoid pregnancy, with the chance getting four times smaller. If you're really worried about pregnancy and don't have the resources for contraceptives, you could place your now-unhappy couple in different beds so they won't do lovin' in the first place.

Contraceptives

There are many surgical methods for altering a pawn's fertility, affecting their chances of natural pregnancy. Some of these are revocable, allowing for pregnancy at a later time, but they have a slight chance of causing permanent sterility if a surgery is botched. You can access these medical operations after researching Fertility procedures. 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 woman from becoming pregnant with the "Implant IUD" operation, which stops pregnancies in the first trimester. One can be placed indefinitely, with the operation requiring 1 medicine. You can later remove it through the "Remove IUD" medical operation, using a qualified doctor and 1 medicine. Women may embark with IUDs already implanted. If either of these operations is botched, the patient will become permanently sterile.

Vasectomy

Like an IUD, this is a semi-permanent way to make a pawn unable to reproduce. The health operation "Perform vasectomy", can be done on any adult male. It requires 1 medicine and is performed like a surgery. The vasectomy can be undone later through the "Reverse vasectomy" operation, also requiring 1 medicine. Both of these operations cause permanent sterility if botched.

Tubal Ligation

This permanently stops a female from being able to reproduce. "Perform tubal ligation" is a medical operation requiring 1 medicine.

Babies

The end result of pregnancy is a human baby.

  • Can't move, do work, or wear clothes. They sleep in a crib.
  • Can only eat from a lactating mother, milk, insect jelly, or baby food.
  • Play need instead of recreation.
  • Surrounding colonists gain mood when near a giggling baby, as well as happy babies in general.
  • Babies cry for -8 mood around them.
  • Growth vats seemingly have no ill effects on a baby or its development, at least until it exits the baby stage.[Not throughly tested] However, parents gain a -4 moodlet.