Do women absorb the DNA of every man they have unprotected sex with?

Do women absorb the DNA of every man they have unprotected sex with?

I’ve been asked many times, mostly by worried pregnant mothers or potential baby fathers if a fetus’s DNA can be changed or effected by either another man’s semen while she is pregnant or from her sexual activities with previous partners.

The short answer is no.

There is a false belief that women absorb and retain the DNA of every man they have unprotected sex with. This belief has been spread through some articles, but stems from a 2012 research project that showed that the brains of some autopsied women had male DNA.  Some who heard this quickly jumped to the conclusion that they must have received this male DNA through sperm.

The truth is, this is called microchimerism and the explanation for the male Y chromosome being found in some female brains is not really that complex.

Pregnancy

When women become pregnant, they play host to another human with its own set of DNA. Some of this DNA gets absorbed through the placenta and remains with the woman for the rest of her life. If she has any male children then she will absorb some male DNA which explains why some of the women autopsied (aged 32 to 101) had male DNA in their brains even decades later.

The DNA a mother inherits from her child is often up to 10% of the free floating DNA in her blood stream. Often call foetal origin cells, they have also been found in the mothers skin and all major organ including the heart.

Blood Transfusions and Organ Transplants

When we receive blood transfusions or organ transplants, we are also receive some DNA from the donor. This is known as medical chimerism and is something the medical world has been aware of for a long time. If a woman receives a transfusion or transplant from a male, it is likely she will also absorb some male DNA.

Having an Older Male Sibling

If a woman has an older brother, the chances are her mother has absorbed some male DNA from him during her pregnancy and also passed it along to her daughter. This explains why some of the women autopsied who did not have any male children, blood transfusions or transplants, still had the presence male DNA.

Effects

Research suggests that having male DNA passed on to these women doesn’t affect them as far as femininity goes, but that it could have several beneficial effects:

  • Lower risk of some cancers
  • Longer life span
  • Better tolerance of successive pregnancies
  • Decrease risk of Alzheimer’s
  • Diminished symptoms of rheumatoid arthritis

So while many women have the presence of male DNA, it’s not because they were having unprotected sex. They do not carry the DNA of ex-lovers and thankfully are not bonded to them for life, however, they will be bonded even on a cellular level with their children til death.

Stress During Pregnancy and it’s Affects on the Unborn Child

I have two close friends who are both first time mothers to be and although both are in healthy relationships and are overall healthy individuals, both of them are incredibly stressed, so much to the point that they both at times get very dysthymic, have trouble eating, sleeping, being intimate, feeling attractive and are easily irritable. 

When asked what exactly they are stressed about, they both answered that they are worried about being good mothers, about being financially secure enough to properly take care of their child, how their child will change their lives and mostly, if their child will be healthy despite all the signs that they are having a normal, healthy pregnancy. 

I found that last part to be very interesting. Their biggest concern was that their child is developing normally and that they will have a healthy child, yet the stress that they are experiencing may play a vital role in the health of their baby. 

Stress is a Part of Life

We all experience stress and pregnant women often experience stress more than any of us. Often times women who are pregnant are busy trying to run house holds, hold down jobs and balance a busy schedule. While stress is normal, how much stress is too much and does it affect the fetus?

It used to be considered a myth that too much stress affects the unborn child, but researchers, including Dr. Calvin Hobel, a perinatologist (an obstetrician who practices maternal-fetus medicine) in Los Angeles who studies the affects of stress on pregnancy, are providing more and more evidence that stress is bad for pregnant women and their unborn child. Stress not only increases the risk of pre-term labor, but also a number of problems after the child is born. 

Women who are stressed release hormones and those hormones “wash” over the fetus. Genetically the fetus is forced to react to environmental cues about how to best construct and respond within the capabilities of that specific gene to what is going on. According to Dr. Pathik Wadhwa, assistant professor of behavioral science, obstetrics and gynecology at University of Kentucky College of Medicine, “The fetus builds itself permanently to deal with this kind of high-stress environment, and once it’s born may be at greater risk for a whole bunch of stress-related pathologies.” 

Some of the most recognizable effects of maternal stress on pregnancy: pre-term births and low birth weight.

Baby’s who are born premature (before 37 weeks) are at risk of many complications later such as developmental delays, learning disabilities, chronic lung disease, pervasive developmental disorders, and even death. There is even research suggesting that babies who express stress in utero are more likely to suffer from heart disease, diabetes and high blood pressure as adults. More recent evidence is pointing to stress in utero affecting the baby’s temperament and possibly IQ. Baby’s who experience a lot of stress in utero are more likely to show signs of depression and irritability and are less likely to tune out repeated, unimportant stimuli, a predictor of IQ. 

Who the Mother is and What She is Like During Pregnancy Affects Who the Baby Will Turn Out To Be

According the the biopsychosocial model, we are who we are determine in part by biological, psychological and environmental influences. Mother’s who experience a lot of stress and anxiety during pregnancy are bathing their unborn child in those chemicals that affect the baby. Stress causes the mother’s nervous system to stimulate the release of epinephrine and norepinephrine which are stress hormones that restrict blood flow and oxygen to the fetus. Research also shows that the placenta in pregnant women who are stressed, releases more corticotropin-releasing hormone (CRH) which tells the body how long a pregnancy should last and helps the fetus reach maturation. This is probably largely responsible for the increase in pre-term birth and low birth weight. 

How much stress is too much stress?

It’s hard to say, it really comes down to the woman, her personality and how she copes with stress. One woman can work two or three jobs and be fine, while one woman may find herself in trouble just trying to hold down one job. The woman needs to listen to her body, her doctor and even her family member’s if they are worried that she is too stressed or anxious. Studies show that extra help for the mother to relive some of the psycho-social stress as well as work leaves as early as 24 weeks cut down on the risk of premature birth by about 21%

Ways to Relieve Stress

Somethings pregnant women can do to relieve stress include yoga (not strenuous yoga of course), biofeedback, guided imagery and deep breathing techniques. Also, having a great support network is crucial. It is important for the pregnant woman to slow down when she starts feeling stressed, even if that means cutting back on certain things and delegating tasks to others. 

Pregnant Women Should Take this Questionnaire! 

One way to measure your stress is to take this questionnaire developed by Dr. Hobel. For every question answer “yes”, “no” or “sometimes”. If you answer “yes” or “sometimes” to three or more questions, Dr. Hobel believes you may be stressed enough to warrant talking to a counselor or your physician to help put together an intervention to help protect you and your unborn child from stress.   

  1. I feel tense
  2. I feel nervous
  3. I feel worried
  4. I feel frightened
  5. I have trouble dealing with problems
  6. Things are not going well 
  7. I cannot control things in my life
  8. I am worried that my baby is abnormal
  9. I am concerned that I may lose my baby
  10. I am concerned that I will have a difficult delivery
  11. I am concerned that I will be unable to pay my bills
  12. I live apart from my partner or spouse
  13. I have extra-heavy homework
  14. I have problems at work
  15. Have you and your partner or spouse had any problems?
  16. Have you been threatened with physical harm?