Table 1 Postulated mechanisms behind less favorable treatment outcome (reduced implantation rate and increased adverse obstetric outcome) after ovarian hyperstimulation
Causes: | Targets |
|---|---|
1-Supraphysiological estrogen levels attained during ovarian stimulation 2-Medications used during ovarian stimulation: •Clomiphene citrate •Gonadotropins •GnRH analogues: agonists & antagonists •HCG used to trigger ovulation 3-Other probable causes: abnormal levels of other hormones, peptides and local autocrine mediators associated with ovarian stimulation | 1-Endometrium 2-Developing oocyte 3-Sperm 4-Developing embryo 5-Maternal endocrine system: ovaries (corpus luteum), pituitary gland and hypothalamus. 6-Other probable targets e.g. •Fallopian tubes •Early developing placenta •Leptin-mediated effects •Coagulation system |