meiosis

When a Zygote Becomes an Embryo Zygotes divide through a process known as mitosis, in which each cell doubles (one cell becomes two, two becomes four, and so on).

mitosis

Implantation typically happens 6–12 days after fertilization. This is the time when women may begin to experience pregnancy symptoms, including: breast tenderness. bloating.

You may be excited to start noticing something different about your appearance, but at 3 weeks pregnant, a belly isn’t really a thing. Though you may feel a bit bloated, most pregnant women don’t start to show until around week 12 or later, so you’ve got quite a way to go before you actually look pregnant.

But stomach pains or cramps are common in pregnancy and usually nothing to worry about. Mild stomach pain in early pregnancy (during the first 12 weeks) is usually caused by your womb expanding, the ligaments stretching as your bump grows, hormones constipation or trapped wind.

Back pain is a normal, if uncomfortable, part of pregnancy for most women. In the first trimester, back pain is commonly linked to an increase in hormones and stress. You may be at a greater risk of back pain during your pregnancy if it’s something you’ve experienced before becoming pregnant, or if you’re overweight.

Even though a lot is going on in your body right now, it isn’t anything you can truly feel. During week 3, you can’t tell that you’re pregnant yet, and you don’t necessarily have any physical symptoms.

Early pregnancy discharge But most pregnant women will secrete sticky, white, or pale-yellow mucus early on in the first trimester and throughout their pregnancy. Increased hormones and vaginal blood flow cause the discharge. It increases during pregnancy to prevent infections as your cervix and vaginal walls soften.