DES Grandchildren

Offspring of a DES Daughter or a DES Son


You may not be able to tell. Hopefully, your parents told you about DES being part of your family health history. If so, they deserve credit because it is not an easy discussion to have.

What might make you suspect DES exposure? If your mom mentioned having problems such as difficulty getting pregnant, miscarriages or reproductive tract cancers. Or, if there was any family discussion about a drug given to your grandmother while she was pregnant. Then you may be a DES Grandchild and should pay attention to that possibility.

Unfortunately, it is nearly impossible these days to obtain medical records from past years, so that avenue of confirmation may not be available to you.



Mice are recognized as good predictors of the human experience. When mice are given DES at the time of development, the resulting health problems in their offspring mirror those seen in human DES Daughters and DES Sons. When their offspring, the DES Grandchildren mice, exhibited health problems, researchers raised a warning flag.

Scientists are taking what they learned from animal studies to investigate whether a drug given to their grandmothers has affected human DES Grandchildren. As study results come in, there is growing evidence that the DES Grandchild generation has been adversely impacted. How that could happen is explained in an excellent article about transgenerational epigenetics published in Mother Jones magazine. The last paragraph addresses the DES experience. As described, toxic exposures don’t actually mutate DNA, but rather they alter how specific genes turn themselves off and on to do the work they are supposed to do in the body. If not activated properly, because of exposure to DES in a previous generation, then health problems may develop.



  • Delayed Menstruation Regularity,Skipping Periods, Having Preterm Birth Delivery
    DES Granddaughters participating in the long-running National Cancer Institute (NCI) DES Follow-up Study reported menstruation starting at about the same age as unexposed women. But it took longer for DES Granddaughters to achieve regular menstrual periods, meaning a period is predictable within five days. This small study also hints at the possibility that infertility may be more frequent in DES Granddaughters. But researchers stress that further studies are needed. Read a review of this research in the DES Action VOICE newsletter.

    An article on a study which appeared in Reproductive Toxicology in December 2018 states that DES Granddaughters have a higher risk of irregular menstruation, of going at least six weeks without a period and of having a preterm birth delivery than other women in the population whose mothers were not DES Daughters. Login to see this article covered in the Winter Voice 2019.

  • Uterus Defects (Possible)
    A French Study on Uterus Defects was covered in the Winter Voice 2020 ”The main finding of the study, published in the journal Therapies, was that abnormalities in the uterus were more common among DES granddaughters than in general population. It’s not yet possible to say definitively that prenatal exposure in their parents is the cause because they were not able to learn about other risk factors the women in their study had which may have also contributed to their uterine defects. The three defects found: MRKH syndrome(the vagina and uterus are underdevleoped or completely absent), doubling of the uterus, bicornate uterus(heartshaped uterus.) It must be noted that this is an initial study which has not been replicated anywhere else yet.
  • Grandsons Higher Genital Defect Risk (Possible)
    Boys born to DES Sons appear to have an increased risk of micropenis and undescended testicles, found a recent small study out of France. The study population was just over 200 DES Grandsons born to fathers prenatally exposed to DES, and only six DES Grandsons showed these problems. But, if future studies confirm these findings, it suggests physical effects on genitals from DES may continue into the third generation, depending on the biological sex of the DES-exposed parent and the DES Grandchild. The study was published in March 2018 in the French journal Therapie. Those 209 DES Grandsons were compared to the general population in Europe, to children born to DES Daughters, and to sons of women not prenatally exposed to DES. (The researchers did not have a group of boys born to unexposed men to use as a comparison group, which is a weakness in the study.) Birth defects occurred in 3.5% of children born to DES Sons, including three cases of cryptorchidism (undescended testes), two cases of hypospadias, and three cases of hypoplasia of the penis (micropenis) in the boys. Perhaps surprisingly, no increased risk of hypospadias was seen among boys born to DES Sons even though it has been seen in sons born to DES Daughters. To see statistical analysis and explanation of what this preliminary study means login to read about it in the Voice Spring 2018 #156. Research shows that congenital abnormalities such as undescended testicles predispose men to testicular cancer. All men should practice testicular self-exam regularly. Any DES Grandsons who may have been born with undescended testicles should be vigilant about practicing the testicular self-exam.
  • Hypospadias
    Studies done in both the Netherlands and France indicate that male children of DES Daughters may be at greater risk for this birth defect than unexposed individuals. Hypospadias is a condition where the urethral opening on the penis is in the wrong place, emerging somewhere down the shaft instead of at the tip. In many cases hypospadias can be corrected with surgery.Of note is that previous studies have failed to replicate this finding until 2018. A recent review paper, conducted by researchers at Dartmouth’s Geisel School of Medicine, published in the journal Current Environmental Health Reports-December 2018, of studies exploring how endocrine disrupting chemicals such as DES might contribute to male birth defects, shows how much more work needs to be done. Several studies, including ones from the US, France, and the Netherlands, have found a substantially higher risk of hypospadias in DES sons, and the French study found a higher risk in DES Grandsons as well. “Among the pharmaceutical agents, sex steroids, DES and progestin fertility treatments have all been associated with hypospadias risk, the researchers concluded. Most of the studies included small groups of participants, making it difficult to understand risks at the population level. Regardless, it is clear that the most sensitive time for exposure for this birth defect is during eight-16 weeks of pregnancy, and there is enough research to establish a strong link to DES in the DES Sons. It appears that hypospadias occurs more frequently in DES Grandsons born to DES Daughters. The mechanism by which DES is linked and causes DES Grandsons to have higher risk of hypospadias has not been uncovered yet. Read a more detailed account of this review paper in the Spring Voice 2019 #160.
  • Tumor Growth
    Animal studies indicate a higher rate of tumor growth in DES Grandson and Granddaughter mice compared with unexposed animals. The study was reviewed in the DES Action VOICE newsletter.
    But researchers caution that more studies are needed to prove conclusively that this finding in DES-exposed mice also occurs in humans. This is being closely watched.
  • Birth Defects in DES Grandchildren (Possible)
    A French study published in the journal Pharmacoepidemiology, in September 2016, led by Michel Tournaire, MD, an OBGYN with the Hospital of Paris, and the DES France Association Network, showed six types of birth defects occurred more frequently among DES Grandchildren, in decreasing risk: esophagus defects; other digestive defects; male genital tract anomalies (especially undescended testicle(s) and hypospadias); cleft lip/palate; musculoskeletal anomalies; and congenital heart defects. The researchers did find a greater likelihood of cerebral palsy among DES Grandchildren that corresponded with a higher rate of preterm birth in the DES exposed group. Cerebral palsy is a neurological disorder resulting from some kind of injury or related problem that happens in a child’s brain while it’s developing. The data came from DES Daughters throughout France who self reported the conditions in their children. These DES Daughters either had their DES Mother’s medical records, or consistent details about their DES Mothers’ being prescribed DES during pregnancy. Read the article covering this study and any bias to the results in the Summer Voice 2017 #153.
  • Overall Cancer Risk
    Human studies of DES Grandchildren, at this time, find no overall increased cancer risk for DES Grandchildren.

    • However, research done as part of the National Cancer Institute DES Follow-up Study found the number of ovarian cancers among DES Granddaughters greater than expected. This finding supports the need for further study and health monitoring of DES Grandchildren.
    • No increases in testicular cancer were found for DES Grandsons, but there has been one case of vaginal/cervical clear cell adenocarcinoma (CCA) in an 8 year old granddaughter. CCA is the cancer for DES Daughters that is linked to prenatal DES exposure. Additional information is in a story in the DES Action VOICE newsletter.
  • ADHD Risk (Possible
    A relatively new study from July 2018 in JAMA Pediatrics entitled Association of Exposure to Diethylstilbestrol During Pregnancy With Multigenerational Neurodevelopmental Deficits found that 7.7% of DES Grandchildren in the study population have attention deficit hyperactivity disorder, compared to 5.2% of children without any links to DES exposure. After accounting for several other factors, the study suggests that DES Grandchildren have a higher risk for ADHD than the general population.The research was observational, using data that had already been collected from the Nurses’ Health Study II for different purposes unrelated to DES. It therefore cannot show that DES exposure caused ADHD in the third generation. There is a chance that other factors might account for the increased risk, including statistical oddities. The study’s finding of a positive link between ADHD and DES exposure in the third generation emphasizes the need for further research into ways the DES third generation might differ from the general population. As more studies identify these differences, if they are replicated in additional studies, it will become easier to determine what effects may directly result from DES exposure in the third generation’s parents. In this most recent study, the strongest finding suggesting possible causation is the increased risk among those whose mothers’ DES exposure was in the first trimester. Login to read the article in the Summer Voice 2018 #157.


Findings from studies of DES Grandchildren are just beginning so doctors may not have heard of them. Tell your doctor of your DES exposure and that you would like to discuss it further in subsequent visits. Note your exposure on the intake form or request that your doctor do so on your chart.

Currently, there are no special health screenings identified for DES Grandchildren.

It is best to stay aware, not overly concerned but rather informed as research continues into DES Grandchild medical issues.