Oocyte donation: a risk factor for pregnancy-induced hypertension: a meta-analysis and case series

Abstract

Background: In 2008 and 2009, the authors saw in their institution three women who had undergone oocyte donation and went on to develop severe de novo hypertension before the 26(th) week of gestation, with values above 180/110 mm Hg. Pregnancy was prematurely terminated in these cases because of the acute threat to the mother's life, and none of the three neonates survived. Five further cases with better outcomes were found to have occurred from 2006 to 2010. On the basis of this experience, the authors performed a meta-analysis to determine whether oocyte donation elevates the risk of pregnancy-induced hypertension (PIH). The cases are discussed in detail.

Methods: Systematic review of the literature on PIH after oocyte donation, with meta-analysis and calculation of an odds ratio. We also provide a retrospective chart review of our own case series.

Results: 28 publications were evaluated. The overall rate of PIH in a total of 2308 deliveries after oocyte donation was 22.6%. With the aid of data from 11 studies, the course of pregnancy in a total of 644 oocyte recipients was compared to that in a control group of 2320 women who were not oocyte recipients. The calculated odds ratio for PIH after oocyte donation, compared to conventional reproductive therapy, was 2.57 (95% CI, 1.91-3.47), while the calculated odds ratio for PIH after oocyte donation, compared to other women in the control group, was 6.60 (95% CI, 4.55-9.57).

Conclusion: The data reveal that oocyte donation confers a considerable risk that the recipient will develop PIH. The very early and severe cases of preeclampsia that we report here are rather atypical; similar cases may have occurred elsewhere without finding their way into the relevant literature. The authors recommend close surveillance of pregnancies following allogenic oocyte transplantation by physicians with special expertise in prenatal medicine.

Figures

Figure 1

The forest plot shows the risk calculation for hypertensive disorders of pregnancy as odds ratios with 95% confidence intervals according to the random effects model after oocyte donation compared with women with deliveries of autologous oocytes. It was not clear from the 5 studies whether or to what extent assisted reproductive interventions preceded the pregnancies in the control group. (e7, e15, e18, e22, e27). df=4, I2=21.2%. Test for heterogeneity: p = 0.509. Studies in any language were included that compared the outcome of pregnancy and obstetric complications during delivery after 24+0 weeks’ gestation after embryo transfer of a heterologous oocyte (egg donation) with a control group. Studies with fewer than 6 participants were not included

Figure 2

Forest plot showing the risk for hypertensive disorders of pregnancy after oocyte donation as odds ratios with 95% confidence intervals according to the random effects model compared with women with pregnancy after assisted reproductive interventions, but of autologous oocytes, such as for example IVF or insemination. The association was investigated in 6 studies. (e9, e12, e20, e23, e25, e28). df=5, I2=10.6%. Test for heterogeneity: p = 0.477. Studies in any language were included that compared the outcome of pregnancy and obstetric complications during delivery after 24+0 weeks’ gestation after embryo transfer of a heterologous oocyte (egg donation) with a control group. Studies with fewer than 6 participants in each group were not included.

Figure 3

Hypothetical causes and pathomechanisms of pre-eclampsia (according to Sibai et al, 2005)