Sometimes you must sleep excessively during pregnancy in the third trimester due to physical exhaustion from thriving a baby and the stress it puts on the body. However, after the first trimester, your energy should return. During the beginning of pregnancy, your blood pressure and blood sugar levels also lower, which may make you feel tired. Sleep will be irresistible to you since your hormones change, particularly the extra progesterone that comes with being pregnant. One of the first symptoms you may notice is overwhelmingly tiredness and even exhaustion when pregnant. Also, lack of sleep during pregnancy can lead to several complications, including preeclampsia which may result in preterm birth.
Also, the amount of sleep you get while you're pregnant not only affects you and your baby but could also affect your labour and childbirth as well. However, you may start to worry if you feel the need to sleep all the time. Are you pregnant and sleepy? Developing a human baby is hard work, so it's not surprising if you feel a little extra tired during your pregnancy.