Increase in transforming growth factor beta1 in ovarian follicular fluid following ovarian stimulation and in-vitro fertilization correlates to pregnancy

We have analysed the content of the growth and differentiation regulatingpeptide, transforming growth factor beta1 (TGFbeta1), in follicular fluidfrom patients undergoing in-vitro fertilization (IVF), and correlatedconcentrations of TGFbeta1 with the outcome of the IVF treatment and theconcentrations of 17beta oestradiol in serum at ovum retrieval. A total of88 women with infertility of >3 years duration and age <38 yearsparticipated in the study. During IVF treatment, follicular fluid andmatched serum samples were collected at ovum retrieval and analysed forTGFbeta1, oestradiol, progesterone, follicle- stimulating hormone (FSH) andluteinizing hormone (LH) using radioimmunoassay and enzyme-linkedimmunosorbent assay. We found that the TGFbeta1 content in the follicularfluid at the time of oocyte retrieval correlated positively with subsequentpregnancy. In 29 women who became pregnant following IVF, follicular fluidTGFbeta1 values were significantly higher (P=0.005) than in 59 women whereIVF was unsuccessful. In the pregnant group, TGFbeta1 values correlatedpositively with oestradiol at ovum retrieval. TGFbeta1 also correlatedpositively with the number of fertilized oocytes. TGFbeta1 may thus beimportant for successful human pre-embryo development, contribute tosuccessful embryo implantation and development and may be necessary for theestablishment of pregnancy.