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Pregnancies achieved from oocyte, sperm or embryo donation are unique, since they have resulted from donor gametes that are immunologically foreign to the mother. Thus, studying the obstetric outcome of such pregnancies may shed some light on the pathophysiology of preeclampsia, particularly in women conceiving with donated embryos, since the entire fetal genome is allogenic in these pregnancies. In this retrospective cohort study, a total of 144 women were studied. Of these, 72 were infertility patients who had conceived as a result of sperm, ovum or embryo donation and the other 72 women were age- and parity-matched control patients who became pregnant with their own gametes, either spontaneously, or following intrauterine insemination with their partner's spermatozoa. Study patients were divided into three groups depending on the origin of the donated gametes. Group 1 consisted of pregnancies achieved by intrauterine insemination with washed donor spermatozoa (n = 33). Group 2 included women who conceived using donated oocytes (n = 27) and group 3 consisted of women who conceived as a result of embryo donation (n = 12). The incidence of pregnancy-induced hypertension in the donated gametes study group was 12.5% (9/72) compared with 2.8% (2/72) in the control group. In addition, pre-eclampsia was diagnosed in 18.1% (13/72) of the donated gametes study group compared to 1.4% (1/72) in the age- and parity-matched controls. The increased incidence of gestational hypertension in pregnancies resulting from donated gametes gives evidence for a maternal genetic component, with an equally strong fetal influence, in the complicated aetiology of gestational hypertension, and pre-eclampsia in particular.

Pyruvate and glucose uptake by 73 individual human oocytes and preimplantation embryos was measured non-invasively, using an ultramicrofluorescence assay to analyse changes in substrate levels in microdroplets of culture medium. The uptake of both substrates was measured over successive daily incubations between days 1 (unfertilized oocytes) or 2 ('spare' embryos which were not transferred) and day 6 (day 0 = day of insemination). Under these conditions, 58% (25/43) of fertilized embryos with two pronuclei on day 1 developed to the blastocyst stage by day 6. The pyruvate uptake of these embryos increased from approximately 28 to a maximum of 40 pmol/embryo/h between days 2.5 and 4.5. Similarly, glucose uptake increased from approximately 8 to 14 pmol/embryo/h between days 2.5 and 4.5, but then increased further to 24 pmol/embryo/h on day 5 at the blastocyst stage. [corrected] The pyruvate uptake of fertilized embryos which arrested at cleavage stages was significantly lower than for those which developed to the blastocyst stage. Polyspermic and parthenogenetic embryos, and unfertilized oocytes also had lower pyruvate uptakes at later stages. The glucose uptake of unfertilized oocytes and abnormal embryos never reached the level of fertilized embryos at the blastocyst stage on day 5.5. Non-invasive measurement of pyruvate uptake before embryo transfer may provide a valuable functional criterion for the selection of viable embryos capable of developing to the blastocyst stage.

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