Some pregnant women feel quite healthy during the nine months leading up to the birth of their child. The anticipation and joy of bringing a new life into the world lifts their spirits and helps them deal with their changing bodies. On the downside, more than half of all women experience pregnancy nausea and vomiting, a condition called morning sickness – and these symptoms can be quite challenging for some. Fortunately, they usually go away by the end of the first trimester. What causes nausea in pregnancy?
What Causes Nausea in Pregnancy?
No one knows for sure what causes pregnancy nausea and vomiting. Not surprisingly, most theories center around the hormonal changes a woman experiences during her nine months of pregnancy.
Estrogen Plays a Role in Pregnancy Nausea and Vomiting
During pregnancy, estrogen levels soar compared to the pre-pregnancy state. This rapid rise in estrogen levels is one theory as to why morning sickness happens to women. So why aren’t all women affected? No one knows why some pregnant women become nauseated with higher estrogen levels, but it may depend on how much estrogen her body produced prior to the pregnancy.
Women who have the greatest changes in estrogen levels may be the most susceptible to pregnancynausea and vomiting. Interestingly, studies don’t show a correlation between estrogen levels and whether or not women get morning sickness, so estrogen may not be the complete story.
Another hormone that may cause nausea during pregnancy is human chorionic gonadotropin, or HCG. HCG is produced by the developing embryo and the placenta, and some researchers think it’s actually HCG levels that trigger morning sickness – or a combination of HCG and estrogen. HCG also stimulates the ovaries to produce estrogen, so it may have an effect indirectly by increasing estrogen production.
Another hypothesis is that progesterone, another hormone that rises during pregnancy causes morning sickness. Other theories are that pregnancy nausea and vomiting offers a survival advantage. The developing fetus is most sensitive to toxins during the first three months of pregnancy and feeling nauseated during that time reduces the changes that a mom-to-be will eat something that will harm her unborn baby.
What Causes Nausea in Pregnancy: The Bottom Line?
No one knows for sure what causes pregnancy nausea and vomiting, but it’s most likely hormone-related. There’s little you can do about your fluctuating hormones, but taking simple steps like eating smaller meals more frequently and having a saltine first thing in the morning helps. Ginger may also be an effective, natural treatment for morning sickness, but talk to your doctor first. There’s some controversy as to whether ginger is safe for all women during pregnancy although most recent studies show that it is. The good news? Morning sickness is short-lived for most women and will soon subside.
