Our long term hypothesis is that giving premature infants breast milk that was pumped during the night and has high concentration of melatonin will improve outcome of several clinical conditions related to premature infants. Prior to testing this, we need to learn the pharmacokinetics of melatonin in vitro.

In this preliminary research we would like to check the levels of melatonin in breast milk pumped during the night, and evaluate the rate of degradation of the melatonin to determine the half life of melatonin in pumped breast milk (in vitro).

The study includes 10 nursing women. Each woman will bring a frozen 5 ml sample of breast milk that was pumped at 03:00 AM. The samples will be collected at the NICU department of Carmel Medical Center and will be stored at deep freeze (-20°C). The samples will be numerically coded and will be kept anonimously. After defrosting the samples, melatonin concentration will be checked in the hospital laboratory every hour, for 4 hours. If meltonin levels will be detectable after 4 hours, continous measurements will be done at 8 hours and at 12 hours after defrosting. The samples will be tested with IBL Melatonin ELISA kit. For control we will use breast milk that was pumped at 10:00 am (when melatonin excretion is minimal). At the end of the analysis the samples will be thrown away.

Inclusion Criteria:

1. Women that are breast feeding and will pump and freeze a milk sample at 03:00 AM
2. Women at least one week after delivery

Exclusion Criteria:

1. A sample that will not be freezed right after the pump
2. Women that are taking hypnotic drugs
3. Women that are taking melatonin

only women that gave birth and are breast feeding their babies

healthy women who are breast feeding