Last week, I wrote about how to get abducted by aliens in The Sims 3. I talked a bit about alien pregnancy in that guide. But because there’s so much to it, I thought the topic deserved its own post.
In this guide, we’ll cover all aspects of alien pregnancy in The Sims 3 – from how to get your Sim pregnant to giving birth to your alien baby.
Please Note: All information below assumes you are NOT using mods. There are mods that allow females to become pregnant from abductions, increase chances of pregnancy, etc. See the mods section at the end of the post for more information.
How to Get Pregnant by Aliens
When young adult, adult, or elder male Sims are abducted by aliens, there’s a 33 percent chance they’ll return pregnant. I have an entire post about how to get abducted so I won’t go into too much detail here. But for the sake of completion, we’ll cover it briefly.
To get your Sim abducted by aliens, go outside between the hours of 12:00 AM – 3:00 AM. Stargaze through a telescope (additional +13% chance) and/or have space rocks in your Sim’s inventory (additional +38% chance). Unlike in The Sims 2, stargazing is not necessary to be abducted, but it does help!
This is the only way to get pregnant by aliens without using mods. You need to get abducted and hope that your Sim returns pregnant. If not, try again!
How to Know Your Sim is Pregnant
Once your Sim returns from an abduction, they will have an “Abducted” moodlet that lasts for 10 hours. Once it expires, if your Sim has an “Unexpected Weight Gain” moodlet, this means they’re pregnant.

If the abducted moodlet expires and your Sim does not have the weight gain moodlet, they did not become pregnant from the abduction.
Your Sim will also display other signs of pregnancy such as weight gain and the pregnancy walk after the first 24 hours. You may also see your Sim touches his belly while a creepy sound plays in the background.

Alien Pregnancy Differences
In The Sims 3, alien pregnancy works a bit differently than in it did The Sims 2.
Like in the previous game, only male Sims can become pregnant through alien abduction. But in TS3, alien pregnancy is treated differently than a normal female pregnancy. Here are the ways it differs:
- No maternity leave for “pregnant” male Sims
- No maternity clothes
- No restriction from activities that pregnant female Sims can’t do
- No genetic information passed to the baby
Why is this the case? Well, in my opinion The Sims 3 has the most realistic alien pregnancies.
The male Sim is not actually pregnant. Instead, he simply serves as the vessel or host for the alien baby. This is the reason why elder males can also become pregnant in The Sims 3. As the baby grows inside him, he gains weight and eventually the baby is “born” as a pure alien – not a hybrid.
The baby will have 100% alien DNA. It gets no genetic information from its father or “host” Sim, as he was just an incubator for the baby. After the baby is born, you will not see its alien parent in the family tree. Only your Sim will appear as the parent.

Giving Birth to an Alien Baby
After the “Unexpected Weight Gain” moodlet expires, your Sim will give birth to the alien baby. This takes about 48 hours – a day less than a normal Sim pregnancy.
Male Sims cannot have the baby at a hospital. Once your Sim goes into labor, you’ll receive a dialogue box that gives you a choice – raise the child or send it back to its homeworld.

If you choose “Raise,” you’ll be prompted to name the baby and he or she will be added to your household. If you choose “Send to Homeworld,” the baby will be whisked away after birth. Choose wisely because if you send it home, you’ll never get the baby back.
After making your choice, your Sim goes through “labor.” His belly glows green and he appears to “push” as if he were giving birth. After a few minutes, he’ll spin around and the baby will appear in his arms.

If you choose to raise the baby, she doesn’t require any special care besides what a baby typically needs. However, she’ll grow up to have alien powers including mind control and the brain power motive.
If you choose to send her back to homeworld, your Sim will put the baby down and she’ll disappear in a blur of light. Your Sim will wave goodbye, and you’ll never see the baby again. She will not show up in your Sim’s family tree and it will be as if she never existed.
However, your Sim will still have the memory of having a baby if you look in their personal scrapbook.
Alien Pregnancy Mods
There are a few mods I can recommend to enhance the Sims 3 alien pregnancy experience:
- Abductor – Gives females a chance of being impregnated by aliens when abducted. Also allows you to set pregnancy percentage.
- More/Less Frequent Male Pregnancies – Allows you to change the odds of male Sims becoming pregnant from abduction. There are four flavors to choose from – no male pregnancy, low chance, high chance, higher chance.
Oh no, Christopher Steel! 😂 He pushes the baby out . . . but out where? Thanks for the guide. Is there any way to put on post notifications for your blog?
Hi Christine! LOL. I have no idea where he pushes that baby out from! Also, I removed my email subscription because I thought it might be annoying since I’m posting a lot these days. But I have reactivated the service. If you want to subscribe to receive new post notifications, you can do so in the sidebar. Thank you!
Done! Thanks Cindy, I look forward to seeing your next post!