It is quite expected for a pregnant woman to think that her inability to sleep very well in the night might affect her baby. The truth is a pregnant woman might be experiencing insomnia, but the baby inside is not in any way affected by this. This is because your baby sleeps most of the time, whether you are awake or not. Your baby is safe as long as you are only bothered about insomnia, as there are other things that can pose a danger to the well-being of your baby.
However, you should be worried when the effects of insomnia on you have become so much that they start affecting your proper functioning. For example, one of the symptoms of insomnia is sleepiness or tiredness during daytime. You might be driving or engaging in some activities that require your concentration, but the effect of insomnia on you might cause you to sleep during this period. However, failure to concentrate might lead to an accident which can also affect the baby