Sex - Pregnancy
Unless disabled in settings, Sims pregnancy is initiated during sex and it can only occur in vaginal or climax sex category. It takes 10 sim-minutes for possible impregnation to happen, which by default is announced with a notification.
Pregnancy can occur only once a day per sex partner. Attempting pregnancy the same day with the same partner after already failing to impregnate will not yield a different result.
Sims after sex are not pregnant right away, they can only be potentially pregnant. Getting potentially pregnant multiple times in a row with different partners creates a possibility to get pregnant with any of them.
Only after a day passes or a pregnancy test is done, are Sims able to tell if they are pregnant or not.
Pregnancy Occurrence (Chance)
The chance of becoming pregnant depends on Pregnancy Mode setting.
On the Simple Pregnancy Mode, the chance of becoming pregnant is manually set by the player. Two separate settings are used to set the pregnancy chance for playable Sims and NPC Sims. No additional pregnancy-related mechanics are present.
For pregnancy to occur between player Sims and NPC Sims, both pregnancy chance settings have to be set to a value higher than 0%.
On the Menstrual Cycle Mode, the chance of becoming pregnant depends on a Sim menstrual cycle day which determines the fertility of that Sim.
Every Sim that can get pregnant has its own unique menstrual cycle which consists of PMS days, Period days, and fertility days.
PMS days occur at the end of the cycle.
Period days occur in the first days of the cycle.
Few days before the ovulation day are the fertility days which can range from 10% to 36% of becoming pregnant, and the ovulation day grants a chance of becoming pregnant as high as 84% and as low as 49%.
The fertility of a Sim can be checked by sending them to the toilet and performing the Fertility Test.
Sims with the ‘Fertile’ trait always have a 20% boost to the current pregnancy chance and Sims that went through the Fertility Treatment process available through the phone can have as high as 250% boost or as low as 150% boost to the current pregnancy chance. The effect of the Fertility Treatment is temporary and will decay once the next ovulation day passes.
Sims that can impregnate, which are generally males, have a chance of failing depending on their age. Young adults have a 91% chance, adults have an 85% chance, and elders have a 75% chance of impregnation. The possibility of failure doesn’t exist if the Sim to impregnate went through the Fertility Treatment process.
Sims pregnancy can be avoided through the use of birth control. Condoms, as well as Birth Control Pills, can be bought through the online sex shop available on any computer. Ordered boxes will arrive every Monday or Tuesday morning, which then have to be taken out of the mailbox and unpacked inside the Sim inventory.
Unless disabled in settings, Sims will use birth control automatically when required. Birth Control Pills will be used every day and condoms will be applied during sex that can cause pregnancy.
By default, Sims birth control is imperfect. Condoms have a 5% chance of failing and Birth Control Pills have a 9% chance of failing.
As the last option, Sims can terminate the pregnancy when in the first or second trimester by using the pregnancy termination service available through the phone.
The process of pregnancy itself is not affected by WickedWhims.
Menstrual Cycle Data:
Very Long Cycle - Adult: 21-30 days (21-40 days for younger), PMS: 3-6 days, Period: 2-5 days
Long Cycle - Adult: 18-24 days (18-30 days for younger), PMS: 1-3 days, Period: 2-4 days
Normal Cycle - Adult: 8-10 days (8-15 days for younger), PMS: 1-2 days, Period: 1-2 days
Short Cycle - Adult: 6-7 days (6-10 days for younger), PMS: 1 day, Period: 1 day