pubmed-article:2920966 | pubmed:abstractText | The effects of ritodrine, administered by intravenous, intramuscular or per os routes, upon plasma levels of unconjugated estriol, estradiol, progesterone and human placental lactogen (HPL) were investigated in 24 third-trimester pregnancies. Ritodrine administered at a constant rate of 200 micrograms/min for 3 h, injected intramuscularly 8 x 10 mg/day for 5 days or given orally in doses of 6 x 20 mg/day for 10 days resulted in a significant decrease in the steroid hormone concentration and a significant elevation of HPL levels. | lld:pubmed |