The risk that a woman's pregnancy will end in miscarriage is apparently connected to the age of her male partner, says a new study from overseas.1
Since it's believed that chromosome abnormalities in sperm appear to increase as men age,2,3 it's also theorized that increasing male age contributes to miscarriage since abnormal sperm often plays a role.4 However, the link between a man's age and miscarriage risk was previously "not established", wrote Remy Slama, MD, an epidemiologist at the French National Institute for Health and Medical Research (INSERM) in France, and his colleagues.
Emotional Toll of Pregnancy Loss
When miscarriage occurs, it can be emotionally devastating. Emotions may range from anger to despair, and experts say it's essential to give yourself some time to grieve. Some ways to move toward the healing process include creating memories of your baby, taking each day one-at-a-time, taking care of yourself, postponing major decisions, keeping a journal, and seeking help from others or a support group.5
It's estimated that among women who are aware of their pregnancy, about 15% end in miscarriage. When doctors use the term "miscarriage", they are usually describing the loss of a pregnancy from natural causes before the 20th week. There are different causes for miscarriage; some are known and others are not known. One condition that can heighten the miscarriage risk includes polycystic ovary syndrome (PCOS), which is also a known cause of infertility. Other women experience recurrent miscarriage, which in some cases, a genetic abnormality in the mother may be to blame.6
Male Age Connection?
For their study on the influence of male age, Slama and his co-investigators in the United States and Germany set out to interview more than 5,000 women starting in 1990 and 1991 until the end of their pregnancy. During the study, nearly 500 women in that group had a miscarriage.
After excluding the influence of maternal age, the researchers then measured the risk of miscarriage for each woman between weeks 6 and 20 of their pregnancies. They found that the risk was 27% greater when fathers were over age 35 compared to fathers under that age. They then examined the risk of miscarriage among women under age 30. In those cases in which the father was over age 35, the risk was about 50% higher, they found. But they also noted there was a lower risk in all these cases for early second trimester pregnancy loss.
"In conclusion, the risk of spontaneous abortion increased with increasing paternal age, with a suggestion that the association is stronger for first trimester losses," wrote Slama's group.
Underlying Causes
While the reasons that older paternal age has a greater influence on miscarriage risk were not investigated in this study, Slama points to other research that has suggested that chromosome abnormalities in sperm increase as men age.7 For example, after a review of the medical literature, a group of researchers at the Lawrence Livermore National Lab in California published findings last year suggesting that sperm cells are more vulnerable as men age, showing greater levels of chromosome abnormalities.
Thus, Remy theorizes that the transmission of these chromosome defects from sperm to embryo result in miscarriage.
1. Slama R, Bouyer J, Windham G, Fenster L, Werwatz A, Swan SH. Influence of paternal age on the risk of spontaneous abortion. Am J Epidemiol 2005 May 1;161(9):816-23.
2. Asada H, Sueoka K, Hashiba T, Kuroshima M, Kobayashi N, Yoshimura Y. The effects of age and abnormal sperm count on the nondisjunction of spermatozoa. J Assist Reprod Genet 2000 Jan;17(1):51-9.
3. Bosch M, Rajmil O, Martinez-Pasarell O, Egozcue J, Templado C. Linear increase in diploidy in human sperm with age: a four-color FISH study. Eur J Hum Genet 2001 Jul;9(7):533-8.
4. Al-Hassan S, Hellani A, Al-Shahrani A, Al-Deery M, Jaroudi K, Coskun S. Sperm chromosomal abnormalities in patients with unexplained recurrent abortions. Arch Androl 2005 Jan-Feb;51(1):69-76.
5. Mayo Foundation for Medical Education and Research. Coping with Pregnancy Loss. Available at: http://www.mayoclinic.com/invoke.cfm?id=PR00098. Accessed June 8, 2005.
6. National Institute of Child Health & Human Development. National Institutes of Health. Research on Miscarriage and Stillbirth. Available at: http://www.nichd.nih.gov/womenshealth/miscarriage.cfm. Accessed June 8, 2005.
7. Sloter E, Nath J, Eskenazi B, Wyrobek AJ. Effects of male age on the frequencies of germinal and heritable chromosomal abnormalities in humans and rodents. Fertil Steril 2004 Apr;81(4):925-43.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include overseeing health news coverage for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.
