ABSTRACT
Pharmacodynamic effect of levonorgestrel (LNG) present in small amounts in infant's circulation has not yet been studied adequately. In our present study, nine women were taking oral minipills (LNG 30 micrograms daily) and 10 were using subdermal implants, Norplant(R)-2, during early postpartum period from four weeks to 15 weeks. These were healthy lactating women in age group 20 to 35 yrs, who had full-term normal delivery of male infants. Daily 4-hour urine samples (from 8 AM to 12 noon) were collected from four weeks onwards to 15 weeks for estimations by radioimmunoassays of follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T) levels. No significant differences (P greater than 0.05) were found between geometric means of the total area under curve at weekly intervals for FSH, LH and T hormones between the male infants from control group (n=10) when compared with oral minipill or Norplant(R)-2 users. These results are reassuring for future sexual growth and development of children who are exposed to contraceptive steroids during their infancy; however, they do require further confirmation by long-term epidemiological studies incorporating monitoring and surveillance of such children.
