LHRH agonist buserelin : contraception for breast feeding mothers

• Main Author: Dewart, P. J.
• Published: University of Aberdeen 1991
• Subjects: 615.1
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.592335

This thesis details the investigations performed to determine the safety, acceptability and effectiveness of buserelin as a contraceptive agent for lactating mothers. In a survey to establish the demand for an alternative method of contraception, a questionnaire on breast feeding and contraceptive practices was sent out to 630 mothers. Half were breast feeding, the mean breast feeding persistence was 5.05 months, range 7 days to 20 months. The most popular methods of contraception were the progestogen-only pill (48%) and the condom (28%), 12&37 were not using contraception whilst lactating. It was hypothesized that some buserelin would pass into the breast milk, this had to be quantified and possible biological effects on the infants had to be excluded before proceeding with the study. Lactating mothers were given 600μg buserelin by nasal spray and their breast milk was analysed. The maximum concentration of buserelin detected in the breast milk of mothers in this study was 12.6ng/ml. Biological effects on the breast feeding infants were excluded by monitoring their urinary gonadotrophin levels. The effects on lactating mothers of chronic treatment with buserelin on hormonal levels, ovulation, bleeding patterns and nursing practice were studied. From six weeks post partum nine mothers took 300μg buserelin intra-nasally daily for the duration of their breast feeding (mean of 216 days). Urinary levels of LH, oestrone and pregnanediol were compared to those of nine control mothers. Ovulation occurrred in 7 of the control mothers; time to first ovulation varied from 90 to 296 days. There were no ovulations in the treated group. There were no side effects reported. Buserelin nasal spray has the potential to provide effective contraception for lactating mothers.