In week 25 of your pregnancy, your baby continues to mature and develop, and as with other earlier weeks, week 25 is no exception when it comes to developmental strides.
During week 25, your baby's lungs are preparing to work outside of the womb and are rapidly developing, although they are not mature at this point.1,2
This MNT Knowledge Center feature is part of a series of articles on pregnancy. It provides a summary of each stage of pregnancy, what to expect, and insights into how your baby is developing. Take a look at the other articles in the series:
You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.
Symptoms at 25 weeks pregnant
In addition to weight gain and a growing belly that is now the size of a soccer ball, at this stage of your pregnancy you may continue to experience physical pregnancy symptoms.1
Constipation and hemorrhoids are two symptoms that may be experienced around week 25 of pregnancy.
These symptoms commonly include:1
- Varicose veins
- Carpal tunnel syndrome
- Restless leg syndrome
- Symphysis pubis dysfunction (pelvic pain)
- Rapid hair growth.
Your hormones at 25 weeks pregnant
Throughout your pregnancy, you will experience variations in certain hormones that contribute to many of the pregnancy symptoms you may experience.
Following implantation of the fertilized egg, your body begins to secrete a hormone called human chorionic gonadotrophin (hCG) - the hormone used to detect pregnancy. This hormone is also responsible for regulating estrogen and progesterone and contributes to frequent urination.3
Initially produced by the corpus luteum, progesterone rises throughout your pregnancy and continues to do so until the birth of your baby. In early pregnancy, progesterone is responsible for increasing uterine blood flow, establishing the placenta and stimulating the growth and nutrient production of the endometrium (lining of the uterus).3
Progesterone also plays a crucial role in fetal development, preventing premature labor and lactation, as well as strengthening the pelvic wall muscles to prepare your body for labor.
In addition to progesterone, the placenta is vital in secreting important hormones during your pregnancy such as:3
- Human placental lactogen: this hormone is believed to be responsible for mammary gland growth which will be important for lactation following the birth of your baby. Additionally, it plays a role in increasing nutrient levels in your blood, which is vital to the growth and development of your baby.
- Corticotrophin-releasing hormone: this hormone is not only responsible for determining how long you will be pregnant, but also for your baby's growth and development. Later in pregnancy, the rise in both corticotrophin-releasing hormone and cortisol both completes fetal organ development and provides the mother with a surge of cortisol that has been linked with maternal attentiveness, increasing the mother-baby bond.
Another vital hormone in pregnancy is estrogen, which is responsible for fetal organ development, placental growth and function and mammary gland growth. Additionally, estrogen is needed for the regulation of other hormones produced during pregnancy.3
Because of the rise in progesterone and estrogen, you may experience some unpleasant pregnancy symptoms such as mood swings and morning sickness. Another hormone, relaxin, can cause physical symptoms such as pelvic pain, balance difficulties and constipation due to its role in relaxing maternal muscles, ligaments and joints.3
Screening tests at 25 weeks pregnant
You will likely be hearing a lot about gestational diabetes at this point in your pregnancy and your doctor will likely be planning on screening you for the condition.
During week 25 of pregnancy, your baby's nostrils will open and their lungs will continue to develop.
Low- and average-risk women will be tested between weeks 24 and 28. During the initial glucose challenge test, you will be asked to drink a sugary solution that is syrupy in texture. You will need to have a blood test after 1 hour to determine your blood sugar level.4
A normal result is below 130-140 milligrams per deciliter (mg/dL) or 7.2-7.8 millimoles per liter (mmol/L).4 If your results are abnormal, you will require a follow-up glucose tolerance test which will require overnight fasting.
During the follow-up screening test, you will undergo a blood test to check your sugar following the fasting period.
After the blood test, you will be asked to drink a sugary drink which has more sugar than the drink in the initial phase of testing. During this test, your blood sugar will be tested hourly for 3 hours; gestational diabetes is diagnosed if two of the three blood results show higher than normal glucose levels.4
Baby's development at 25 weeks pregnant
At 25 weeks pregnant, there are many changes in your baby's development. Developments that are underway include:1,2
- Head and neck: auditory and visual systems are activated by fetal brain waves; lips and mouth are increasingly sensitive; vision is improving with responses to light; permanent teeth buds are high in the gums
- Lungs: while development continues, at this point, the lungs cannot transfer oxygen to the bloodstream and exhale carbon dioxide; lungs continue to produce surfactant that prevents the lungs' tissue from sticking together
- Other: rapid fetal weight gain, nostrils open.
Lifestyle changes at 25 weeks pregnant
As with earlier weeks, you will soon find out that there are many lifestyle modifications which need to be made during pregnancy and even after delivery.
During pregnancy, you will need to take care of yourself and your developing baby. Be sure not to drink alcohol or smoke during pregnancy, and avoid all other toxic substances such as drugs during this time.
Be sure to discuss all medications you are taking with your health care provider to ensure that you should continue use during your pregnancy.5
To nourish yourself and your baby, make sure you eat a healthy diet and take a good prenatal vitamin.
Another way to maintain your health during pregnancy is to get regular exercise. Speak with your health care provider about your current or desired exercise regimen to make sure it is safe.5
While it is safe to eat fish during pregnancy, it is recommended that you limit your intake to 8-12 oz. of fish and shellfish per week.6-8
Some examples of fish that are safe to consume during pregnancy include shrimp, salmon, canned light tuna (note: mercury varies can to can), pollock, cod, catfish and anchovies.7,8 If you plan on eating albacore tuna and tuna steak, it is recommended that you limit consuming this fish to 6 oz. per week.6,8
Avoid eating shark, swordfish, tilefish and king mackerel while pregnant, as they contain high levels of mercury which can be harmful to your baby's brain and nervous system.6 If eating fish from a non-commercial source - a fish you or your family caught, for example - be sure to check with the local health authorities that the waters in which it was caught are safe.6
Always make sure your food is fully cooked and not raw or undercooked. Also avoid uncooked smoked or pickled fish.6 Additionally, it is important to avoid unpasteurized soft cheese, refrigerated pâté, raw or undercooked meat and poultry, cold cut deli meat, foods containing raw eggs (Caesar dressing, etc.) and unpasteurized juice, milk and eggnog.6
Need a boost? Caffeine is OK during pregnancy but should be consumed in moderation. Try to keep your caffeine consumption from all sources at or below 300 milligrams daily.6
Baby's size at 25 weeks pregnant
At week 25 of pregnancy, your baby will be around the size of a rutabaga.
Your baby is now the size of a rutabaga or two juice boxes stacked on top of each other, measuring over 9 inches long and weighing more than a pound and a half.1,9
If you have questions regarding your pregnancy, be sure to contact your health care provider.
Call your doctor if you are experiencing symptoms of an ectopic pregnancy or miscarriage such as vaginal bleeding or passage of tissue, leaking vaginal fluid, feeling faint or dizzy, low blood pressure, rectal pressure, shoulder pain and severe pelvic pain or cramping.
A new study suggests that metformin - a drug commonly used to treat diabetes and considered safe for use in pregnancy - has potential to prevent or treat preeclampsia, a pregnancy complication that can be life-threatening and currently has no cure.