“…Treatment with ovulation-stimulating fertility drugs causes recruitment and maturation of multiple ovarian follicles, temporarily elevating estrogen; in women treated with clomiphene citrate (CC), the peak serum levels of estrogen are two-to threefold higher than normal (average: 200 pg/mL at peak) (3,4), and peak levels are even higher in women who undergo in vitro fertilization (IVF) treatment, which typically involves the use of folliclestimulating hormone (FSH)-containing drugs (5,6). If pregnancy results, the supernumerary ovarian corpora lutea produce both estrogen and progesterone and raise the levels far above normal in the first 9 weeks (7,8).…”