DENVER — Infertile women with blood type O have an increased prevalence of diminished ovarian reserve, according to Dr. Edward J. Nejat.
In contrast, the A blood group antigen, comprising blood types A and AB, appears to be protective against diminished ovarian reserve, he reported at the meeting.
These are novel findings whose clinical implications must await further study, added Dr. Nejat of Albert Einstein College of Medicine, New York.
He presented a cross-sectional observational study involving 563 women under age 45 years seeking treatment for infertility at Montefiore Medical Center in New York or at the Yale University in vitro fertilization program in New Haven, Conn. Diminished ovarian reserve, defined by a baseline serum follicle-stimulating hormone level greater than 10 mIU/mL, was present in 70 subjects.
Ovarian reserve reflects the quantity of gametes available for procreation. Dr. Nejat and his coworkers decided to look for a possible association between blood type and ovarian reserve because other than advancing age, the determinants of ovarian reserve are unclear. Other investigators have previously described a link between blood type A and ovarian hyperstimulation syndrome.
A total of 61% of women with diminished ovarian reserve were blood type O, as were 43% of those with a baseline follicle-stimulation hormone level of 10 mIU/mL. After adjustment of the results for age and site, women with blood type O were at twofold greater risk of having diminished ovarian reserve than were women with other blood types.
The A blood group antigen was present in 26% of women with diminished ovarian reserve and 41% of those with adequate ovarian reserve. The adjusted risk of diminished ovarian reserve in women possessing the A blood group antigen was half that in women with blood types O or B.
Dr. Nejat said he had no relevant financial conflicts.