Prenatal care in your second trimester

In your second trimester, you will have a prenatal visit every month. The visits may be quick, but they are still important. It is OK to bring your partner or labor coach with you.

Visits during this trimester will be a good time to talk about:

• Common symptoms during pregnancy, such as fatigue, heartburn, varicose veins, and other common problems
• Dealing with back pain and other aches and pains during pregnancy

During your visits, your doctor or midwife will:

• Weigh you.
• Measure your abdomen to see if your baby is growing as expected.
• Check your blood pressure.
• Sometimes take a urine sample to test for sugar or protein in your urine. If either of these is found, it could mean you have gestational diabetes or high blood pressure caused by pregnancy.
• Ensure that certain vaccinations are done.

At the end of each visit, your doctor or midwife will tell you what changes to expect before your next visit. Tell your doctor or midwife if you have any problems or concerns. It is OK to talk about any problems or concerns, even if you do not feel that they are important or related to your pregnancy.

Hemoglobin testing. Measures the amount of red blood cells in your blood. Too few red blood cells can mean that you have anemia. This is a common problem in pregnancy, although easy to fix.

Glucose tolerance testing. Checks for signs of diabetes which can begin during pregnancy. In this test, your doctor or midwife will give you a sweet liquid. An hour later, your blood will be drawn to check your blood sugar levels. If your results are not normal, you will have a longer glucose tolerance test.

Antibody screening. Is done if the mother is Rh-negative. If you are Rh-negative, you may need an injection called RhoGAM around 28 weeks of gestation.

You should have an ultrasound around 20 weeks into your pregnancy. An ultrasound is a simple, painless procedure. A wand that uses sound waves will be placed on your belly. The sound waves will let your doctor or midwife see the baby.

This ultrasound is typically used to assess the baby's anatomy. The heart, kidneys, limbs, and other structures will be visualized.

Ultrasound can detect fetal abnormalities or birth defects about half the time. It is also used to determine the sex of the baby. Before this procedure, consider whether or not you want to know this information, and tell your doctor or midwife and your ultrasound provider your wishes ahead of time.

All women are offered genetic testing to screen for birth defects and genetic problems, such as Down syndrome or brain and spinal column defects.

• If your doctor or midwife thinks that you need one of these tests, talk about which ones will be best for you.
• Be sure to ask about what the results could mean for you and your baby.
• A genetic counselor can help you understand your risks and tests results.
• There are many options for genetic testing. Some of these tests carry some risk, while others do not.

Women who may be at a higher risk for these problems include:

• Women who have had a fetus with genetic abnormalities in earlier pregnancies
• Women age 35 or older
• Women with a strong family history of inherited birth defects

Most genetic testing is offered and discussed in the first trimester. However, some tests can be performed in the second trimester or are done partly in the first and second trimester.

For the quadruple screen test, blood is drawn from the mother and sent to a lab.

• The test is done between the 15th and 22nd week of pregnancy. It is most accurate when done between the 16th and 18th weeks.
• The results do not diagnose a problem or disease. Instead, they will help the doctor or midwife decide if more testing is needed.

Amniocentesis is a test that is done between 14 and 20 weeks.

• Your doctor or midwife will insert a needle through your belly and into the amniotic sac (bag of fluid surrounding the baby).
• A small amount of fluid will be drawn out and sent to a lab.

Cell-free DNA testing can sometimes be done instead of amniocentesis. Blood drawn from the mother is the only requirement. Cell-free DNA testing is also called "noninvasive prenatal screening".

Contact your doctor or midwife if:

• You have any signs or symptoms that are not normal.
• You are thinking of taking any new medicines, vitamins, or herbs.
• You have any bleeding.
• You have increased vaginal discharge or a discharge with odor.
• You have a fever, chills, or pain when passing urine.
• You have moderate or severe cramping or low abdominal pain.
• You have any questions or concerns about your health or your pregnancy.

Pregnancy care - second trimester

Gregory KD, Ramos DE, Jauniaux ERM. Preconception and prenatal care. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 8th ed. Philadelphia, PA: Elsevier; 2021:chap 5.

Hobel CJ, Williams J. Antepartum care. In: Hacker NF, Gambone JC, Hobel CJ, eds. Hacker & Moore's Essentials of Obstetrics and Gynecology. 6th ed. Philadelphia, PA: Elsevier; 2016:chap 7.

Ormandy J. Antenatal and postnatal care. In: Magowan BA, ed. Clinical Obstetrics and Gynaecology. 5th ed. Philadelphia, PA: Elsevier; 2023:chap 23.

Smith RP. Routine prenatal care: second trimester. In: Smith RP, ed. Netter's Obstetrics and Gynecology. 4th ed. Philadelphia, PA: Elsevier; 2024:chap 208.

Williams DE, Pridjian G. Obstetrics. In: Rakel RE, Rakel DP, eds. Textbook of Family Medicine. 9th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 20.

Updated by: John D. Jacobson, MD, Professor Emeritus, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.