Pregnancy: DES Effects in DES Mothers and in DES Daughters

Future pregnancy studies should focus on the DES grandchildren

image of a pregnant-woman
Diethylstilbestrol causes a variety of birth-related adverse outcomes in DES daughters such as spontaneous abortion, second trimester pregnancy loss, preterm delivery, stillbirth, and neonatal death.

DES Pregnancy: DES Mothers

Exposure to Diethylstilbestrol during Sensitive Life Stages: A legacy of heritable health effects, National Institutes of Health, NCBI PubMed PMCID: PMC3817964, 2013 June.

Although women were prescribed DES to improve the outcomes of their given pregnancy, the results of a double-blind clinical trial of over 1500 women at the University of Chicago by Dieckmann and coworkers in 1953 demonstrated that DES did not reduce the incidence of spontaneous abortion, prematurity or postmaturity, and the study suggested that DES enhanced premature labor. However, it continued to be used for another nearly 20 years.

DES Pregnancy: DES Daughthers

Hoover determined that DES daughters have an increased risk for many pregnancy-related issues including spontaneous abortion (<14 weeks gestation), ectopic pregnancy, loss of pregnancy in the second trimester (14–27 weeks), preeclampsia, preterm delivery (<37 weeks), stillbirth (at >27 weeks), and neonatal death within the first month of life. Many of these outcomes including ectopic pregnancy, miscarriage, and premature delivery have been reported in more than one study, and appear to be exacerbated effects for which DES was prescribed to prevent.

The effects of prenatal DES exposure on the ability to reproduce are substantial. The risk for infertility (defined as ≥ 12 months of trying to conceive) among DES daughters is reported to be 33% compared to 14% in unexposed women (p<0.001), and full-term infants were delivered in the first pregnancies of 84.5% of unexposed women compared with 64.1% of DES exposed women (RR=0.76, 95% CI, 0.72–0.80). The Dutch DES cohort reports that 33% of DES daughters are nulliparous at the age of ≥ 40 yr, compared with only 17% in the Dutch population. Kaufman and co-workers also reported that that once pregnant, 20% of DES daughters experience preterm delivery (versus 8% of unexposed population (RR=2.93; 95% CI, 2.23–3.86)), their risk of ectopic pregnancy was 3 to 5 times higher than unexposed women (RR=3.84; 95% CI, 2.26–6.54), and 20% of the DES-exposed group had a miscarriage during the first pregnancy (versus 10% unexposed (RR=2.00; 95% CI, 1.54–2.60). These adverse pregnancy-related outcomes in DES daughters are also experienced by unexposed women, but the excess risk in those outcomes (not stillbirth) owing to in utero DES exposure was significant. Also, there are strong data suggesting that the presence of vaginal epithelial changes at cohort entry examination adds to the cumulative risk for DES-induced infertility, spontaneous abortion, preterm delivery, and ectopic pregnancy.

Click to download the full study.

More DES DiEthylStilbestrol Resources

Author: DES Daughter

Activist, blogger and social media addict committed to shedding light on a global health scandal and dedicated to raise DES awareness.

Have your say! Share your views