Pregnancy week 13
Week 13 of pregnancy is a great time of relief because, at this point, most women are more likely to carry their pregnancy to term. A little over 2 inches and barely under 3 inches long, the fetus weight about .7 ounces during week 13. By the end of the week, the baby’s eyes will have moved closer together from the sides of the head, the intestines will have extended more fully into the body, and the pancreas will have begun making insulin. Because of the growing bundle inside the uterus, many women will begin feeling round ligament pain during week 13. Round ligament pain consists of a curt jabbing pain in the lower abdomen which may be followed by a lingering ache lasting for a short while. Although completely normal when making sudden movements or changes in position during week 13 and on, if the pain is accompanied by cramping, vomiting, or bleeding a physician should be notified immediately.
Sometimes, the incapacity to bear children cannot be determined until this week.
A miscarriage in the later terms of pregnancy could signify an incompetence cervix. This means that the cervix is too weak to remain closed during pregnancy and the baby will arrive too soon. However, even in this rare case, a procedure known as a cerclage can be used to sew the cervix closed and deliver a healthy baby to term. Women tend to start feeling healthier and more energetic during week 13. Also, most women report that their libido returns at week 13 and find that they are more sensitive in all areas of their body, including the genitals, because of increased blood flow. Intercourse and orgasms can be very arousing at this point. However, it is important to reassure each partner that intercourse during this week can be perfectly safe if it is not a high risk pregnancy. The breasts continue to grow during this week and develop more benign bumps than usual.
Current guidance (today's medical sources): Week thirteen marks the end of the first trimester. The baby is developing fingerprints and vocal cords, and the body is beginning to grow in proportion to the head. Many people find energy returning and nausea fading as the second trimester begins. Routine prenatal visits continue on the schedule set with a provider.
Contact your healthcare provider promptly about heavy vaginal bleeding, severe or persistent abdominal pain, a high fever, severe or sudden headache, vision changes, or fainting. Seek urgent care if you are worried — these can be signs that need medical attention.
Sources: NHS — 13 weeks pregnant; Mayo Clinic — Fetal development: The 1st trimester; MedlinePlus (NIH/NLM) — Prenatal Care. Informational only. See our sources & medical-review policy.
Frequently asked questions
How many months is 13 weeks pregnant?
Week 13 falls in the first trimester. Pregnancy is usually counted in weeks (about 40 in total) rather than months, because weeks are more precise.
What is happening to the baby at 13 weeks?
Vocal cords form; fingerprints appear; the baby's body begins to catch up to the head in size.
What symptoms are common at week 13?
The first trimester ends; energy often returns in the weeks ahead. Symptoms vary a lot from person to person; discuss anything that worries you with your healthcare provider.
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See the week-by-week guide →Informational only — not medical advice. Pregnancy Week to Week is a general educational reference. It is not a substitute for professional medical care, diagnosis, or treatment. Every pregnancy is different: always consult your doctor, midwife, or other qualified healthcare provider about your own pregnancy, and never disregard or delay professional advice because of something you read here. In an emergency, contact your maternity unit or local emergency number immediately.