When can I find out my baby's sex?

Your baby's sex can often be determined by ultrasound between weeks 16-20. Some blood tests (NIPT) can determine sex as early as 10 weeks. If you are eager to know, ask your healthcare provider about your options.

Is the second trimester really easier?

For most women, the second trimester is the most comfortable phase. Nausea typically fades, energy returns, and the discomforts of late pregnancy have not yet begun. Many women refer to it as the "honeymoon period" of pregnancy.

Second Trimester 13 weeks pregnant

Pregnancy Week 13 - Welcome to the Second Trimester!

Welcome to the second trimester! At 13 weeks, your baby is about the size of a peach. Unique fingerprints are forming on your baby's tiny fingertips, and vocal cords are developing. Many women find the second trimester to be the most comfortable phase of pregnancy.

Peach

Baby Size

7.4 cm

Length

23 grams

Weight

Week 13

of 42

Baby Development This Week

Your baby's fingerprints are forming — they will be unique and unchanging for life. Vocal cords are developing in the larynx. The placenta is now fully providing oxygen and nutrients to your baby. Your baby's body is growing faster than the head, which is becoming more proportionate. Tiny ribs are visible, and the spleen is producing red blood cells. If you are having a boy, the testes have descended from the abdomen. If a girl, the ovaries already contain millions of eggs.

Changes in Your Body

The second trimester often brings welcome relief from first-trimester symptoms. Your energy levels may increase, and nausea may fade. You might notice a dark vertical line appearing on your belly (linea nigra), and your belly button may be flattening. Some women develop stretch marks as the abdomen grows. Your breasts may still be tender but likely less so than in previous weeks.

Common Symptoms at Week 13

More energyDecreased nauseaGrowing bumpLinea nigraStretch marksBreast tenderness (lessening)

Tips for Week 13

Enjoy the increased energy — take walks, do light exercise, and tackle your to-do list.
Apply moisturizer to your belly to help with skin stretching and itching.
Start a baby name list if you have not already.
Begin thinking about your birth plan and preferences.

When to Call Your Doctor

Report any vaginal bleeding, severe abdominal pain, fever, or signs of preterm labor (contractions, pressure in pelvis).

Frequently Asked Questions — Week 13

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