28th week of pregnancy: timing of anti-D vaccination

By (embryologist) and (embryologist).
Last Update: 08/10/2023

The 28th week of pregnancy is the last week of the seventh month of gestation. The baby already looks more like a newborn. At this point, the pregnancy is quite advanced, so the uterus occupies a large part of the belly and the digestive tract is somewhat compressed. For this reason, it is advisable to eat a small amount several times a day.

In addition, in the 28th week of pregnancy it is common to have constipation problems or even hemorrhoids. Drinking fruit and olive oil can help avoid these problems.

Normally, ultrasound monitoring at this stage of pregnancy should be every two to three weeks to check that everything is progressing normally. It is advisable for the pregnant woman to take advantage of these consultations with her doctor to ask her any questions she may have.

Symptoms and changes in the mother in the 28th week

The 28th week of pregnancy is part of the third trimester of gestation, so fetal development is well advanced. Thus, the woman's uterus continues to stretch. The height of the uterus at 28 weeks of pregnancy is approximately 23-27 cm.

One of the most typical discomforts of pregnant women with 28 weeks of gestation is a swelling in feet and ankles due to fluid accumulation. A tip to improve this discomfort is to drink large amounts of water and activate circulation with a daily walk of at least 30 minutes. In addition, women continue to gain weight and become increasingly fatigued.

It may also happen that the stomach does not accept large amounts of food and heartburn occurs. Other symptoms in pregnant women at the end of the seventh month of pregnancy are stretch marks, backaches, sciatica, hemorrhoids, varicose veins, leg cramps and edema, etc.

Tips in the 28th week of pregnancy

As is the case throughout pregnancy, following a balanced and healthy diet is essential to provide the fetus with the necessary nutrients. In addition, good hydration must be maintained. Drinking large amounts of water will decrease fluid retention, thus favoring the reduction of swelling in the feet.

Practicing physical activity adapted to pregnancy, such as daily walking, would improve blood circulation. In the event that the pregnant woman has urine leakage, it would be advisable to start doing Kegel exercises. Thanks to these exercises it is possible to strengthen the pelvic floor, improving urinary incontinence.

You can also use creams to prevent the appearance of stretch marks in the belly area or take relaxing infusions of lime blossom or lemon balm to combat gestational insomnia.

What does the baby look like in the 28th week of pregnancy?

At the end of the 28th week, the fetus is about 38 cm long from head to toe. Its weight is around 1,050 grams on average. If the baby's weight is between 700 and 1,230 grams, there is no need to worry, as it is within the normal range.

The baby's lungs at 28 weeks of gestation have almost completed their development. Therefore, in case of birth, the premature baby would have a chance of survival, although it would need to receive special care such as assisted respiration, feeding and incubator.

The main problem in 28-week preterm infants is usually due to the fact that the lungs have not yet produced surfactant, a substance that prevents complete lung collapse between every two breaths. In addition, there is very little fat under the skin, so the thermal control system is not yet working effectively. Precisely from this week on, fat accumulates in your body, so your wrinkled skin begins to stretch.

Another change that occurs in the 28th week of pregnancy is that the baby's eyes open and the eyelashes begin to grow.

Prenatal check-up at 28 weeks

Although it depends somewhat on the protocol followed by the physician, it is likely that during the 28th week of pregnancy a urine test that detects the concentration of sugar and albumin will be performed.

The glucose test is recommended to be performed between the 24th and 28th week. Through this study it is observed if there is a risk of suffering from gestational diabetes. Many women during pregnancy experience an increase in blood sugar levels. Therefore, if elevated glucose levels are detected in the analysis, then another more accurate test called a glucose curve is performed.

In this gestational week, the Anti-D vaccine is also indicated in women with a negative Rh to prevent incompatibility with the baby. If maternal blood and fetal blood are mixed during early gestation, a sensitizing effect is produced. Instead, in later gestations, a miscarriage could occur because the mother would have antibodies that would attack the fetus.

For this reason, and to prevent this from happening, the Anti-D vaccine is given to Rh-negative women who have had an abortion, maternal and fetal blood contact or if they have previously had an Rh-positive baby.

If you would like to know more about this, we invite you to read the following article: Maternal isoimmunization due to Rh incompatibility, what are the risks?

FAQs from users

Is bleeding in the 28th week of pregnancy normal?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

The 28th week of pregnancy is part of the third trimester of gestation and, therefore, the final stretch. If at this time the woman suffers spotting or bleeding, the best thing to do is to inform the doctor so that he/she can make the necessary assessments.

The origin of bleeding in the third trimester of pregnancy can be multiple: cervical insufficiency, placenta previa, premature detachment of the placenta, etc.

Can a foetus be born in the 28th week of pregnancy?

By Marta Barranquero Gómez B.Sc., M.Sc. (embryologist).

Yes, a baby can be born at the end of the seventh month of pregnancy and would be considered extremely premature. In these cases, babies will remain in the incubator for as long as the specialist deems necessary and will receive special care such as assisted breathing or feeding.

Is it normal to have cramps in the third trimester of pregnancy?

By Victoria Moliner BSc, MSc (embryologist).

Yes, it is perfectly normal to suffer from cramps during this period. The third trimester is the time when most pressure is exerted on the legs and when the uterus reaches its maximum capacity for expansion. Therefore, the force exerted on the pubis reaches its maximum, making cramps more frequent.

Suggested for you

You are finishing the seventh month of pregnancy and you may be interested to know about the changes that will occur in the next month of pregnancy: What happens in the eighth month of pregnancy - Symptoms and care.

On the other hand, we have discussed that it is important to control glucose levels since there is a risk of gestational diabetes. For more information about this pathology, you can visit the following link: What is gestational diabetes - Causes, symptoms and treatment.

We make a great effort to provide you with the highest quality information.

🙏 Please share this article if you liked it. 💜💜 You help us continue!


B Trolle. Prenatal Rh-immune prophylaxis with 300 micrograms immune globulin anti-D in the 28th week of pregnancy. Acta Obstet Gynecol Scand. 1989;68(1):45-7. doi: 10.3109/00016348909087688 (View)

T F McElrath, J L Hecht, O Dammann, K Boggess, A Onderdonk, G Markenson, M Harper, E Delpapa, E N Allred, A Leviton; ELGAN Study Investigators. Pregnancy disorders that lead to delivery before the 28th week of gestation: an epidemiologic approach to classification. Am J Epidemiol. 2008 Nov 1;168(9):980-9. doi: 10.1093/aje/kwn202 (View)

Wen Xiong, Xin Li, Tianjiao Liu, Rui Ding, Linbo Cheng, Dan Feng, Duan Duan, Mi Su, Yalan Li, Xiao Yang, Sumei Wei. Potential resolution of placenta previa from the 28th-to the 36th-week of pregnancy: A retrospective longitudinal cohort study. Placenta. 2022 Aug;126:164-170. doi: 10.1016/j.placenta.2022.07.006. Epub 2022 Jul 9 (View)

FAQs from users: 'Is bleeding in the 28th week of pregnancy normal?', 'Can a foetus be born in the 28th week of pregnancy?' and 'Is it normal to have cramps in the third trimester of pregnancy?'.

Read more

Authors and contributors

 Marta Barranquero Gómez
Marta Barranquero Gómez
B.Sc., M.Sc.
Graduated in Biochemistry and Biomedical Sciences by the University of Valencia (UV) and specialized in Assisted Reproduction by the University of Alcalá de Henares (UAH) in collaboration with Ginefiv and in Clinical Genetics by the University of Alcalá de Henares (UAH). More information about Marta Barranquero Gómez
License: 3316-CV
 Victoria Moliner
Victoria Moliner
BSc, MSc
Degree in Biochemistry and Biomedical Sciences from the University of Valencia (UV). Master's Degree in Biotechnology of Human Assisted Reproduction from the UV and the Valencian Infertility Institute (IVI). Presently, she works as a Research Biologist. More information about Victoria Moliner

Find the latest news on assisted reproduction in our channels.