It is very important to get bird nest from credible sources.
You must ensure that the bird nests are free from chemicals, dyes and bleach.
Currently, there are many freelance bird nest sellers in the market, where they get their bird nests from house farm in other countries.
Although it is cheaper, but how can we ensure that the swiftlets' habituat are conducive? Are they building nests near wires, cables, TV? Are the swiftlets breathing in air pollutants? Are the swiftlets drinking water from the drains?
Therefore please check your bird nest's source carefully.
Feel free to ask me questions on bird nest, or alternatively, You can learn more from Bird Nest
Happy mummy, Happy baby! Enjoy your motherhood! =)