Minimal monitoring of ovarian hyperstimulation: a useful simplification of the clinical phase of in vitro fertilization treatment.

OBJECTIVE

To investigate the feasibility of IVF treatment with minimal monitoring during ovarian hyperstimulation.

DESIGN

Retrospective analysis and prospective study with real-time control group.

SETTING

Transport IVF program with transport clinic and satellite clinics.

PATIENTS

One hundred consecutive IVF cycles monitored at a transport clinic and 100 concurrent consecutive cycles monitored at satellite clinics, using the same stimulation-monitoring protocol and resulting in oocyte aspiration, are compared retrospectively for the number of ultrasound (US) measurements carried out during monitoring and for results of IVF treatment. No patient selection took place. After introduction of a minimal monitoring protocol at a transport clinic, a prospective study was started comparing 100 minimal monitoring cycles at a transport clinic with 100 concurrent conventional monitoring cycles at satellite clinics, all resulting in oocyte aspiration. Patients entered the retrospective or prospective study only once. In all cases the same laboratory facility was used. Monitoring of ovarian hyperstimulation was done with US measurements only. Cycles were canceled for impending ovarian hyperstimulation syndrome (OHSS) when > 35 follicles were seen to develop during hyperstimulation.

RESULTS

Retrospective analysis shows no difference for the average number of US measurements at transport and satellite clinics (2.8 +/- 0.9 and 3.0 +/- 1.0; mean +/- SD). No differences were found in the number of ongoing pregnancies obtained in the two groups: 22 and 18, respectively. One case of severe OHSS occurred in the satellite clinic group. Introduction of minimal monitoring at the transport clinic gives a significant reduction of the average number of US measurements at the transport clinic compared with satellite clinics, where conventional monitoring continued to be used (1.5 +/- 0.8 versus 2.8 +/- 0.9). Ongoing pregnancies at transport and satellite clinics numbered 33 and 26, respectively. In both groups one patient developed severe OHSS. Sixty-two percent of cycles at the transport clinic were monitored with one US measurement only. No cancellations for impending OHSS occurred during the study period.

CONCLUSION

A large group of patients need only one US measurement during monitoring of ovarian hyperstimulation. Minimal monitoring gives a useful further simplification of the clinical phase of IVF treatment, without adverse effects on treatment outcome and incidence of OHSS.