The effects of prior gravidity on the outcomes of ovum donor and own oocyte cycles.

OBJECTIVE

To determine the effects of prior gravidity on hormonal parameters, medication regimen, oocyte parameters, fertilization, and clinical pregnancy rates (PRs) in donor and own oocyte cycles.

DESIGN

A retrospective study of 64 first-attempt ovum donor cycles and 102 first-attempt IVF and ZIFT cycles using own oocytes conducted during a 2.5-year time period. Analyses of covariance and t-tests using gravidity of oocyte source (gravida versus nulligravida) and controlling for sperm parameters were used to assess differences in hormonal, endometrial, medication, and demographic parameters and were performed separately for donor cycles and for own oocyte cycles.

SETTING

Private fertility center.

PATIENTS

In ovum donation cycles, oocyte parameters, medication administered, and hormonal parameters of 64 oocyte donors between the ages of 21 and 35, 34 of whom were never pregnant, i.e., nulligravida and 30 who had ever been pregnant, regardless of the outcome of that pregnancy, i.e., gravida, were studied. In own oocyte cycles, oocyte parameters, medication administered, and hormonal parameters of 102 women, 54 nulligravida and 48 gravida, between the ages of 23 and 44 were studied.

MAIN OUTCOME MEASURE

Medication requirements, hormonal response, seminal parameters, oocyte quality, fertilization, and clinical PRs.

RESULTS

For patients using their own oocytes, there were no significant differences in any of the parameters studied. In contrast, compared with their nulligravida counterparts, gravida oocyte donors had fewer poor quality oocytes, had more high quality oocytes that fertilized, had a higher proportion of their oocytes fertilize, and had a higher PR per transfer.

CONCLUSION

A prior history of gravidity is an important predictor of clinical pregnancy in donor oocyte cycles but not in cycles in which patients use their own oocytes. Oocyte recipients may wish to consider donor gravidity in selecting their donor.