Question

The first trimester is a period of great vulnerability and it is often a time when a woman does not even realize she is pregnant.

why is this stage so difficult to pass? why wouldn't we be evolutionarily adapted to more successful pregnancies at this point?

Answer 1

1. why is this stage so difficult to pass?

For many women, the intense tiredness of the first trimester is pretty a surprise. And it’s a specially challenging transition for those who are normally go-getters with lots of energy. Women who normally want solely 6 hours of sleep at night often locate they want nearly double that at some stage in these first weeks of pregnancy. And, for others, daylight hours tiredness is paired with bother sleeping deeply or for more than a few hours at night. Nausea and vomiting can also be a big drain on your energy.

Morning Sickness and Nausea
The nausea "morning sickness" that many women experience during the first trimester of pregnancy is the result of hormonal changes. Morning sickness (which isn't necessarily limited to mornings) may actually be a positive thing though you may not feel particularly grateful.

Morning sickness usually disappears after the first trimester.

Mood Swings
Women are often surprised that they don't feel more buoyant at the start of pregnancy especially when it is a long-awaited result. The stresses of the first trimester can produce many emotional ups and downs. Although you may be delighted that you're pregnant, the hormonal adjustments you're experiencing can make you feel anything but joyous. You may experience mood swings, fatigue and insomnia, anxiety about your ability to experience a successful pregnancy, and fear about what will happen.

Constipation

Constipation is a fact of life for most pregnant women. Hormonal changes are largely responsible, signaling food to move more slowly through your system as it nourishes your fetus.

Fatigue
Your entire system is fully engaged in creating a healthy environment for your fetus producing the placenta, a process that is completed at the end of the third month, as well as providing sufficient nutrients. Every organ is engaged in a vast reorganization. No wonder you're tired.

Food Aversions and Cravings
The food cravings and aversions that many women experience during pregnancy are something of a mystery. While you may crave what's good for you and be repelled by foods that are harmful, it doesn't always work that way. Your best strategy is to eat what's right for you and try to find replacements within your diet for the harmful foods you may crave.

2. why wouldn't we be evolutionarily adapted to more successful pregnancies at this point?

The first trimester is said to be the most crucial period of pregnancy because at this point, your baby is growing from an embryo to a fetus. The fetus then enters a stage of rapid development, forming most organs, facial features, skeletal tissue and limbs. This puts your growing child at a high risk of developing complications or even worse you could suffer a miscarriage.