I have checked this mod (name self-explanatory):
Alien Pregnancy For Teens Male and Female by Smonaff
The mod works for Seasons but was never updated. I have not personally tested it, but from messages in the associated thread it worked perfectly with Seasons (for male+female, both teen+adult). Afterward it never worked for any other expansion apparently.

I downloaded and checked the code. I can't see a reason with the code fails. The only thing I can see is that the format is 0x8007 (instead of 0x8009 for FT) but I doubt it is a problem, I've seen other mods with older format version number which worked fine.

Nevertheless, I extracted the same code from FT (0x7FB1E9C7:0x0000100B "Get Out - Make Pregnant") which, surprisingly, is quite different. Anyway I made only two changes to the code:

- Changed the check for male/female to female instead of male
- After the check "Age - Am I an adult?" I added another check "Age - Am I a Teen?"

I didn't change anything else. In particular check for Young Adult, bigfoot and Alien Dad are unchanged.

When the abducted Sim returns Home:
- Adult Males aren't pregnant (OK)
- Adult Females play a tune and are pregnant (OK)
- Teen Females play a tune, but aren't pregnant (hum...)

I've checked, and the tune is played in "Pregnancy - Make Pregnant" at the very end of the script, when all the checks are performed, all tokens are created, and the script decided that pregnancy actually occurred. As far as I can tell, this particular function is not overridden by InTeen (actually it doesn't even make checks for age/gender, it assumes that the checks are done before and all it does is set the correct tokens and set the pregnancy controller).

As far as I can tell, the changes I have made are exactly the same as those made in the aforementioned mod above (except I made only two changes, that particular mod actually allowed YA pregnancy too).

I have attached my .package in case you'd like to inspect it (remember, it's based off FT, not sure what other expansion it would work with... of course 100% chance of failure if InTeen not installed).

Any idea what I did wrong?