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I have included these articles so that you can see that our God not only helps us in our infirmities, but gives us pleasure in them as well. So, it is my prayer that these reference articles would be a blessing to you and your spouse as well.

Oral Sex for a safer pregnancy

Journal of Reproductive Immunology

Article can be found at:

Volume 46, Issue 2, March 2000, Pages 155-166


Correlation between oral sex and a low incidence of preeclampsia: a role for soluble HLA in seminal fluid?

Carin A Koelman a, Audrey B.C Coumans b, Hans W Nijman b, Ilias I.N Doxiadis a, Gustaaf A Dekker b, Frans H.J Claas a

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The involvement of immune mechanisms in the aetiology of preeclampsia is often suggested. Normal pregnancy is thought to be associated with a state of tolerance to the foreign antigens of the fetus, whereas in preeclamptic women this immunological tolerance might be hampered. The present study shows that oral sex and swallowing sperm is correlated with a diminished occurrence of preeclampsia which fits in the existing idea that a paternal factor is involved in the occurrence of preeclampsia. Because pregnancy has many similarities with transplantation, we hypothesize that induction of allogeneic tolerance to the paternal HLA molecules of the fetus may be crucial. Recent data suggest that exposure, and especially oral exposure to soluble HLA (sHLA) or HLA derived peptides can lead to transplantation tolerance. Similarly, sHLA antigens, that are present in the seminal plasma, might cause tolerance in the mother to paternal antigens. In order to test whether this indeed may be the case, we investigated whether sHLA antigens are present in seminal plasma. Using a specific ELISA we detected sHLA class I molecules in seminal plasma. The level varied between individuals and was related to the level in plasma. Further studies showed that these sHLA class I molecules included classical HLA class I alleles, such as sHLA-A2, B7, -B51, -B35 and sHLA-A9. Preliminary data show lower levels of sHLA in seminal plasma in the preeclampsia group, although not significantly different from the control group. An extension of the present study is necessary to verify this hypothesis.


Soluble HLA; sHLA-I; Preeclampsia; Sperm; Tolerance; Oral sex

Copyright © 2000 Elsevier Science Ireland Ltd. All rights reserved.


Semen's Antidepressant Properties

National Center for Biotechnology Information

Arch Sex Behav. 2002 Jun;31(3):289-93.

Does semen have antidepressant properties?

Gallup GG Jr1, Burch RL, Platek SM. Author information


In a sample of sexually active college females, condom use, as an indirect measure of the presence of semen in the reproductive tract, was related to scores on the Beck Depression Inventory. Not only were females who were having sex without condoms less depressed, but depressive symptoms and suicide attempts among females who used condoms were proportional to the consistency of condom use. For females who did not use condoms, depression scores went up as the amount of time since their last sexual encounter increased. These data are consistent with the possibility that semen may antagonize depressive symptoms and evidence which shows that the vagina absorbs a number of components of semen that can be detected in the bloodstream within a few hours of administration.

PMID: 12049024

[Indexed for MEDLINE]


Male DNA found in women

National Center for Biotechnology Information

Male Microchimerism in Women Without Sons: 

Quantitative Assessment and Correlation With Pregnancy History

Purpose: Fetal microchimerism, derived from fetal cells that persist after pregnancy, is usually evaluated by tests for male microchimerism in women who gave birth to sons. We 

investigated male microchimerism in women without sons and examined correlation with prior pregnancy history. Immunologic consequences of microchimerism are unknown. We studied healthy women and women with rheumatoid arthritis (RA).

Methods: Y-chromosome-specific real-time quantitative polymerase chain reaction was used to test peripheral blood mononuclear cells of 120 women (49 healthy and 71 with RA). Results were expressed as the number of male cells that would be equivalent to the total amount of male DNA detected within a sample containing the equivalent of 100000 female cells.

Results: Male microchimerism was found in 21% of women overall. Healthy women and women with RA did not significantly differ (24% vs 18%). Results ranged from the DNA equivalent of 0 to 20.7 male cells per 100000 female cells. Women were categorized into 4 groups according to pregnancy history. Group A had only daughters (n = 26), Group B had spontaneous abortions (n = 23), Group C had induced abortions (n = 23), and Group D were nulligravid (n = 48). Male microchimerism prevalence was significantly greater in Group C than other groups (8%, 22%, 57%, 10%, respectively). Levels were also significantly higher in the induced abortion group.

Conclusions: Male microchimerism was not infrequent in women without sons. Besides known pregnancies, other possible sources of male microchimerism include unrecognized spontaneous abortion, vanished male twin, an older brother transferred by the maternal circulation, or sexual intercourse. Male microchimerism was significantly more frequent and levels were higher in women with induced abortion than in women with other pregnancy histories. Further studies are needed to determine specific origins of male microchimerism in women. 


Ejaculation frequency

Harvard Health Publishing

Ejaculation frequency and prostate cancer

Published: March, 2014

PDF article can be found at: Harvard Medical School

Despite the importance of prostate cancer, its causes remain unknown. Scientists do know that genetics plays a strong role, and they have sound evidence that diet and other lifestyle factors are also important.

Since the prostate is a reproductive organ that produces fluid for the ejaculate, researchers have long wondered if sexual factors influence a man's risk of prostate cancer, but a Harvard study provides good news for sexually active men.

The Harvard study

The Health Professionals Follow-Up Study has been collecting information about a large group of volunteers since 1986. All the men are health care providers, including dentists, pharmacists, veterinarians, optometrists, ophthalmologists, and podiatrists. Most are white. In 1992, 29,342 men between the ages of 46 and 81 provided information about their average number of ejaculations per month in young adulthood (age 20–29), middle age (40–49), and in the most recent year. Ejaculations included sexual intercourse, nocturnal emissions, and masturbation.The volunteers provided comprehensive health and lifestyle data every two years until the study concluded in 2000.

The scientists found no evidence that frequent ejaculations mark an increased risk of prostate cancer. In fact, the reverse was true: High ejaculation frequency was linked to a decreased risk. Compared to men who reported 4–7 ejaculations per month across their lifetimes, men who ejaculated 21 or more times a month enjoyed a 31% lower risk of prostate cancer. And the results held up to rigorous statistical evaluation even after other lifestyle factors and the frequency of PSA testing were taken into account.

Data from Down Under

An Australian study of 2,338 men examined the impact of sexual factors on the occurrence of prostate cancer before the age of 70. Like the Harvard research, the Australian investigation evaluated total ejaculations rather than sexual intercourse itself. Like the American men, the Australians who ejaculated most frequently enjoyed a reduced risk of prostate cancer. The effect was strongest for the frequency of ejaculations in young adulthood, even though prostate cancer was not diagnosed until many decades later. Even so, the apparent protection extended to all age groups. In all, men who averaged 4.6–7 ejaculations a week were 36% less likely to be diagnosed with prostate cancer before the age of 70 than men who ejaculated less than 2.3 times a week on average.

Other links

The Australian study did not measure testosterone levels, but the Harvard study did. It found that men who ejaculated frequently tended to have higher testosterone levels than those who ejaculated less often — yet these were the same men who had a reduced risk of prostate cancer. Therefore, if there is any adverse effect of male hormones, it is offset by some protective effects linked to frequent ejaculation. Further study is needed to investigate possible protective mechanisms; in theory, at least, emptying the prostate of potentially irritating or harmful substances might be one such mechanism.

The Harvard study did not evaluate the number of sexual partners reported by the volunteers, but the Australian study did. It found no association, but an earlier study of 1,456 men living in King County, Washington, did find a link. Men who had sex with 30 or more women over their lifetime were two to three times more likely to develop prostate cancer than men with only one partner. Thirty partners may sound like a lot, but boasting did not seem to boost a man's risk, since even a more modest exposure to two to four partners was associated with a 1.7-fold increase in subsequent prostate cancer.

The Harvard study did not report an effect of marital status, but the Australian research suggested that men who had never married may be at lower risk of prostate cancer than men who were married, divorced, or widowed. However, an American study of 146,979 men found that among men with diagnosed prostate cancer, those who were married had a better outcome than those who were divorced, widowed, or single. The researchers at the University of Miami who performed the study did not determine if sexual activity was involved in apparent protection, but since the subjects were elderly men with prostate cancer, it's unlikely.

A piece of the puzzle

Prostate cancer is a puzzling disease, and its causes remain elusive despite intensive study. Doctors don't know whether or not early diagnosis with PSA screening is beneficial. And al-though many methods of treatment are helpful, it's not yet clear which is best.

The studies from the United States and Australia do little to answer these critical questions — but they do open a new avenue for research. Since both report that a high frequency of ejaculation early in adulthood has the greatest impact on the risk of prostate cancer decades later, they call attention to the role of events early in life, when the prostate is developing and maturing. There is certainly precedent for a long lag between cause and effect. For example, childhood sunburn is a major risk factor for malignant melanomas in adulthood, and prenatal factors that influence birth weight appear to influence the lifetime risk for hypertension and heart disease.

In 1807 William Wordsworth wrote, "The child is father of the man." With respect to prostate cancer, though, sexual activity in adolescence may be a predictor of risk in adulthood.

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