Pregnancy is apt to turn any formerly sane and seemingly competent women into a rather unpredictable creature; and with good reason! The culprits, it seems, are our hormones.
The Role of hCG and Early Pregnancy Symptoms
The first hormone to make its appearance after conception is human chorionic gonadotropin (hCG), also called "the announcer of pregnancy," as it is hCG that's picked up by a urine or blood test to determine pregnancy.
In a normal pregnancy, the level of hCG approximately doubles about every two days during the first 10 weeks. HCG keeps the pregnancy hormones known as estrogen and progesterone at their appropriate levels until the placenta has developed enough to take over this function.
If you are pregnant, you've probably already noticed a side effect of hCG—a sensitive bladder. HCG is responsible for increasing the blood supply to your pelvis, which, in turn, makes your bladder want to get rid of the tiniest amount of urine. The good news is that this condition generally eases after the first trimester (although it will return later as baby gets bigger and starts pushing on your bladder).
HCG is thought to be responsible for numerous other symptoms associated with early pregnancy, including nausea and the sometimes resultant vomiting. These symptoms are commonly referred to as morning sickness, although the term is misleading because the queasiness involved can occur at any time, day or night. Morning sickness tends to peak around the eighth to tenth week of pregnancy when hormone levels are highest and should then taper off as the second trimester begins.