# Sperm Invader? **URL:** \ **Category:** Factual Questions\ **Created:** [August 18, 2003, 8:05am UTC](https://boards.straightdope.com/t/sperm-invader/195935 "2003-08-18T08:05:04Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![Homer\_J.Simpson](https://avatars.discourse-cdn.com/v4/letter/h/a698b9/32.png) [@Homer\_J.Simpson](https://boards.straightdope.com/u/Homer_J.Simpson)\ **Post date:** [August 18, 2003, 8:05am UTC](https://boards.straightdope.com/t/sperm-invader/195935/1 "2003-08-18T08:05:04Z")
Does a woman’s body attack sperm as an invader? ---
**Author:** ![Harmonix](https://avatars.discourse-cdn.com/v4/letter/h/3ec8ea/32.png) [@Harmonix](https://boards.straightdope.com/u/Harmonix)\ **Post date:** [August 18, 2003, 9:29am UTC](https://boards.straightdope.com/t/sperm-invader/195935/2 "2003-08-18T09:29:24Z")
I’m fairly certain the answer to that would be yes. ---
**Author:** ![Mudshark](https://avatars.discourse-cdn.com/v4/letter/m/f04885/32.png) [@Mudshark](https://boards.straightdope.com/u/Mudshark)\ **Post date:** [August 18, 2003, 9:44am UTC](https://boards.straightdope.com/t/sperm-invader/195935/3 "2003-08-18T09:44:18Z")
The first thing I thought of was the game Space Invader. ---
**Author:** ![shijinn](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@shijinn](https://boards.straightdope.com/u/shijinn)\ **Post date:** [August 18, 2003, 9:48am UTC](https://boards.straightdope.com/t/sperm-invader/195935/4 "2003-08-18T09:48:25Z")
there can be only one. (left) ---
**Author:** ![Vision\_of\_Love](https://avatars.discourse-cdn.com/v4/letter/v/5f8ce5/32.png) [@Vision\_of\_Love](https://boards.straightdope.com/u/Vision_of_Love)\ **Post date:** [August 18, 2003, 10:07am UTC](https://boards.straightdope.com/t/sperm-invader/195935/5 "2003-08-18T10:07:23Z")
Yes. I don’t have a source right now but I’m pretty sure, as I’ve heard it, and learned about it a few years ago. ---
**Author:** ![Hokkaido\_Brit](https://avatars.discourse-cdn.com/v4/letter/h/d26b3c/32.png) [@Hokkaido\_Brit](https://boards.straightdope.com/u/Hokkaido_Brit)\ **Post date:** [August 18, 2003, 10:19am UTC](https://boards.straightdope.com/t/sperm-invader/195935/6 "2003-08-18T10:19:54Z")
I have a friend who had five miscarriages (and has two healthy children too, thank goodness) as a result of the proteins in her husband’s sperm being recognised by her body as alien, and her immune system rejecting the embryo. She miscarried consitently at about 10 weeks. The two times she got through that barrier, the babies went to term normally. Unfortunately this happened in Japan to a Japanese friend, and my language skills are not up to medical terms! So while I understood the above explanation, I do not know the term for it so can’t look it up to translate… But it does seem to happen - if not right away as sperm, soon after the embryo begins to develop. ---
**Author:** ![Harmonix](https://avatars.discourse-cdn.com/v4/letter/h/3ec8ea/32.png) [@Harmonix](https://boards.straightdope.com/u/Harmonix)\ **Post date:** [August 18, 2003, 12:01pm UTC](https://boards.straightdope.com/t/sperm-invader/195935/7 "2003-08-18T12:01:20Z")
Hokkaido : The Placenta is supposed to secrete some sorta hormone that supresses the immune system withen it, and thus protecting the baby. It sounds like your friend might not be secreting that hormone correctly. Might I suggest a specialist? ---
**Author:** ![Ca3799](https://avatars.discourse-cdn.com/v4/letter/c/9f8e36/32.png) [@Ca3799](https://boards.straightdope.com/u/Ca3799)\ **Post date:** [August 18, 2003, 3:09pm UTC](https://boards.straightdope.com/t/sperm-invader/195935/8 "2003-08-18T15:09:05Z")
Try looking under “anti-sperm antibodies”. ---
**Author:** ![Incubus](https://avatars.discourse-cdn.com/v4/letter/i/c68b51/32.png) [@Incubus](https://boards.straightdope.com/u/Incubus)\ **Post date:** [August 18, 2003, 11:21pm UTC](https://boards.straightdope.com/t/sperm-invader/195935/9 "2003-08-18T23:21:24Z")
Yeah, they do. I saw a show on reproduction on the Learning channel, and one interesting microscope shot they had was a macrophage (I believe) gobbling up a sperm cell. Also I’ve heard that sperm from different men will ‘fight’ each other if they encounter one another. If you combined the semen from 2 different men and looked at the results in a microscope, I’m imagining that you’d probably see a single-celled war going on.