memang belum ada penyebab yang pasti.
beberapa teori terkemuka:
1.karena aktivitas hormonal berlebih saat masa kehamilan
2.untuk melindungi embrio
3.indikasi kehamilan yang baik dan tanda organ embrio mulai berkembang.
4.cara tubuh melindungi embrio atas kemungkinan induknya menelan bahan makanan berbahaya.
argumen penguat(sori masih dalam bentuk poin2):
Unfortunately, no one is exactly sure what causes morning sickness but it would seem that the cause is a combination of issues related to the chemical changes your body is going through. Those changes include
rapidly increasing estrogen and progesterone levels, an enhanced sense of smell and excess stomach acids. It has also been suggested that stress and fatigue that commonly accompany pregnancy also play a role.<---lihat no1
As irritating as morning sickness may be for pregnant women, it may
protect embryos.<---lihat no2
Doctors have long known that morning sickness — the nausea and vomiting usually experienced in early pregnancy — is actually a
good sign of a healthy pregnancy, despite the discomfort it brings.<---lihat no3
Also, morning sickness does not seem to occur in other mammals, only humans, the researchers noted. If morning sickness was the byproduct of conflict between mother and embryo or fetus, one might expect other mammals to have it too.
Instead, morning sickness is usually triggered in specific circumstances — in response to:
* the sight, smell, or taste of meats and strong-tasting vegetables, which were historically likely to contain foodborne microbes or birth-defect-inducing chemicals;
* alcohol and cigarette smoke.
This all suggests morning sickness serves a useful function,
evolving to protect mothers and embryos from things that may be dangerous, the researchers figure.
The reason that humans alone have morning sickness may be due to our extraordinarily broad diet in comparison to other mammals, including other primates, the scientists conjectured. Instead of evolving a range of molecules to defend against toxins, humans just evolved a way to
keep away from dangerous chemicals.<--- lihat no2 dan no4
Note: yang di atas hasil saduran saya, kalau berminat keseluruhan teori yang ada, bisa melihat di bawah ini
- Spoiler:
There is insufficient evidence to find a single (or multiple) cause, but the leading theories for proximate causes include:
* An increase in the circulating level of the hormone estrogen. Estrogen levels may increase by up to a hundredfold during pregnancy.[3] However, there is no consistent evidence of differences in estrogen levels between women who experience sickness and those who don't.[4]
* Low blood sugar (hypoglycemia) due to the placenta draining energy from the mother, though studies have not confirmed this.[5]
* An increase in progesterone relaxes the muscles in the uterus, which prevents early childbirth, but may also relax the stomach and intestines, leading to excess stomach acids and gastroesophageal reflux disease.
* An increase in human chorionic gonadotropin.
* An increase in sensitivity to odors, which overstimulates normal nausea triggers.
* An increase in bowel movement.
* The body's effort to detoxify thoroughly for the health of the developing embryo. This is supported by evidence that the liver and kidneys become more active than usual at the start of a pregnancy[citation needed].
kesimpulannya:
simpulkan masing2 ya^^
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