MUNICH – Women pregnant with an embryo produced by in vitro fertilization of a donated egg developed gestational hypertension at nearly four times the rate of matched women who were pregnant following IVF with a self egg, in a multicenter, case-control study with 580 participants.
In addition, preeclampsia was more than four times higher in the women who had received a donor egg as part of an IVF procedure, compared with women who used a self egg for their IVF, Dr. Hélène Letur-Könirsch reported at the annual meeting of the European Society of Human Reproduction and Embryology.
Mitchel L. Zoler/Frontline Medical News
Dr. Héléne Letur-Könirsch
Although the mechanism underlying this association is not known, one possible explanation is that when a woman carries an embryo that is completely allogenic, it triggers modified immune tolerance that leads to impaired trophoblast implantation. Other candidate hypotheses are that defective genes in the mother trigger abnormal metabolic pathways that cause hypertension and preeclampsia, and that ovarian insufficiency features reduced ovarian steroid production, causing vascular and immunologic changes that lead to pregnancy-induced hypertension.
Results from several prior studies also had shown a link between use of a donor egg for IVF and an increased rate of gestational hypertension and preeclampsia, but most prior studies had been smaller and failed to adequately control for possible confounders, said Dr. Letur-Könirsch, an endocrinologist at the Fertility Center of the Institut Mutualiste Montsouris in Paris.
She and her associates from seven IVF centers in France pooled data from their entire series of IVF cases that involved donated eggs during the period from February 2005 to September 2012, a total of 217 pregnant women. The analysis matched these cases with 363 control women who had IVF pregnancies during the study period using self eggs by parameters such as age, parity, time of pregnancy, and whether the IVF procedure involved transfer of a fresh or frozen embryo.
Women in the study averaged 35 years of age, with 82% aged 39 years or younger. Average body mass index was virtually identical in both groups, about 24 kg/m2, and the live-birth rate was 79% in both groups. All women in both groups were normotensive prior to their IVF procedure.
The incidence of pregnancy-induced hypertension, defined as blood pressure that reached at least 140/90 mm Hg when measured in office on both arms with two separate measurements, was about 29% in the women who received a donated egg and 14% in those who used a self egg. Development of preeclampsia, defined as persistent gestational hypertension plus proteinuria of at least 0.3 g/day, occurred in about 18% of women who received a donated egg and 7% in those who used a self egg.
In a multivariate analysis that controlled for age, pregnancy history, and use of a fresh or frozen embryo, women who used a donated egg had a 3.9-fold increased rate of pregnancy-induced hypertension and a 4.6-fold increased rate of preeclampsia, compared with women who used a self egg – both statistically significant differences.
The findings suggested that before a woman embarks on pregnancy using a donated egg, she should undergo thorough evaluation for preexisting risk factors for gestational hypertension, including hypertension, obesity, diabetes, renal disease, chronic infection, autoimmune diseases such as systemic lupus erythematosus, a family history of preeclampsia, and living at a high altitude. If these risk factors are present, they should be controlled if possible. Women who have one or more of these risk factors may also be candidates for prophylactic treatment with aspirin to prevent development of preeclampsia, especially if they develop pregnancy-induced hypertension.
During pregnancy, women who received a donor egg should undergo regular and frequent blood pressure measurement, as well as assessment for other possible abnormalities such as Doppler ultrasound examination of uterine arteries and measuring serum and urine markers.
"Physicians and patients must be aware of the risk [from donor eggs] to assure that these women get adequate monitoring and management during pregnancy," Dr. Letur-Könirsch said.
Dr. Letur-Könirsch had no disclosures.
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