Effects of blood type on fertility
September 13, 2022 12:04 PM   Subscribe

An older couple I know struggled with fertility for their whole marriage. One of their family members told me it was due to their blood types, but their reproductive story doesn't match what I understand about blood types. Can anyone explain?

Let's call the woman Laurie. She had 3 healthy children by her first husband. Then she married Jimmy. Laurie and Jimmy had 4 miscarriages, followed by only one child. That child had spina bifida causing physical disabilities, as well as moderate intellectual disabilities that I think were related to the spina bifida as well.

A family member said, "Laurie and Jimmy had the same blood type, O-, and couples with the same blood type can't have babies."

I always thought if the couple's -/+ blood type was mismatched, then the woman could have one baby, but subsequent pregnancies would fail because her immune system would think the baby's blood type was essentially an allergen. But Laurie and Jimmy's first pregnancies weren't viable, and their 5th pregnancy was the only one that was viable.

Also, the family member believed that the child's disabilities were a further sign of Laurie and Jimmy's genetic / blood incompatibility. But I thought the spina bifida was more likely to be a coincidence, since I believe it's either based on dietary folic acid deficiency or can be inherited... but either way, it would NOT be related to the couple's overall fertility issues.

Anyway I'm curious on a scientific level, but of course I didn't want to interrogate anyone's personal life beyond what was voluntarily disclosed to me, so I thought I'd anonymize the details and ask here. Thank you for any insight!
posted by nouvelle-personne to Science & Nature (5 answers total)
Best answer: i can only speak on the RH- part of it, but they have that mixed up. I am negative, husband postive. First baby positive. I received the RhoGam shot to help my body accept any future pregnancies. If my first baby had been negative also, i would not have needed the antibodies as I would not have been exposed to the postive blood. The exposure is what causes the problem.
posted by domino at 12:22 PM on September 13, 2022 [3 favorites]

Best answer: domino's explanation makes sense. erythroblastosis fetalis is the name of the condition.
It almost always happens with Rh- mothers and Rh+ fathers who have an Rh+ child.

There are some studies that say that women with blood type O are at increased risk of pregnancy defects, but... I've never looked into it because it just sounds like poorly-controlled-study-with-clickbait-headline stuff. I think it pointed to a lower egg reserve generally?

I could be wrong!

But that statement is wrong. Laurie and Jimmy had poor luck or else other medical issues. People with the same blood type conceive and deliver healthy babies all the time
posted by Acari at 1:33 PM on September 13, 2022

Best answer: domino and acari have summarized the only evidence for different blood groups affecting fertility / neonatal survival. Mother must be Rh -ve & father must be Rh +ve && shared offspring must also be +ve. It's a European problem because there Rh -ve genes run at 15% but the frequency is much lower elsewhere. But since the 1970s there has been a European solution where the mother's circulatory system is flooded with Anti-D antibodies [domino's RhoGam shot] very shortly after birth if there is Rhesus incompatability. "European" includes white folks in former colonies. [MeBlog for more Rhesus]

blood group O is associated with some diseases, group A with others but I've not heard about any association with O-A-B and neural tube defects like spina bifida. [MeBlog for more-O-A-B] Nor is there any association with increased maternal age and spina bifida - although there is with Down's Syndrome. Additional dietary Folic acid is still recommended for every woman planning to get pregnant and the condition does run in families.

Hope helps.
posted by BobTheScientist at 2:44 PM on September 13, 2022 [3 favorites]

Best answer: Spina bifida is often caused by folate (vitamin B9) deficiency. Folate deficiency can *also* increase the risk of miscarriage.

Depending on the couple's age - since you mentioned "older" - I thought I'd mention something else that may have had an impact.

If one of the parents (yes, including the male parent) was exposed to Agent Orange, there's a reasonable chance that it was the cause of the spina bifida. The possible exposure timeline is pretty broad. If there's a possibility of this, and the person with spina bifida is still alive, and they (or their caretaker) are unaware, it might be a good idea for someone to let them know. There may be benefits available depending on the level of disability.
posted by stormyteal at 1:40 AM on September 14, 2022

Response by poster: No Agent Orange but thanks for mentioning that! Very possible there was dietary folate deficiency - the couple was often lower-income so their diets may have sometimes been sub-par or had less access to vitamin pills.

But I do know for sure that spina bifida also has a genetic form that’s unrelated to folate and just want to re-iterate that not all forms of it can be prevented by the mom’s diet (since so many moms of kids with SB feel “blamed”).
posted by nouvelle-personne at 8:45 AM on September 14, 2022

« Older Strategies for Boundaries in Arguments with...   |   Salty maple-syrupy water: yes or no? Newer »

You are not logged in, either login or create an account to post comments