Regardless of country or era, all human beings have one thing in common. We all spent the first few months of life in our mother’s womb. Some spent longer there than others, but every life started with a pregnancy. Although we only start counting our age from the day we were born, our lives actually began – albeit hidden from view – some months earlier. In many respects, this first stage of our existence plays a crucial role in shaping our future development and life in general. This article provides a comprehensive overview of pregnancy including early signs, physical changes, dietary adaptations, and risks.
1. A brief guide to pregnancy
Every human life begins with a pregnancy and yet no two pregnancies are the same. Pregnancy usually lasts 40 weeks, counting from the first day of the last menstrual period. However, the shortest recorded pregnancy to produce a healthy baby lasted a mere 21 weeks and 5 days. To put this into context, any baby born before 37 weeks of pregnancy is known as a premature or pre-term baby [1, 2].
The end result of a labor and delivery lasting around 3 to 12 hours is usually a healthy baby weighing between 3 and 3.5 kilograms – one of nature’s little miracles. But here too, not all pregnancies are the same. The smallest ever newborn baby who grew up to be healthy weighed just 244 grams, while the biggest tipped the scales at an impressive 10.2 kilograms. In Germany, an average of 1.59 babies are currently born per woman. However, the record for the greatest number of healthy babies is held by a Russian woman who gave birth to an incredible 16 pairs of twins, 7 sets of triplets, and 4 sets of quadruplets – giving a grand total of 69 babies [2, 3, 4, 5].
2. Signs and symptoms of pregnancy: an overview
Depending on a couple’s life situation, the way a pregnancy starts can be very different. Some couples long to become pregnant while others are confident that they are using effective contraception – only for life to throw them a curveball. But whatever the starting point, the end result is the same. They suddenly find themselves pregnant.
At this stage, “pregnant” simply means that an egg (ovum) released in the woman’s body during ovulation has been successfully fertilized by a male sperm cell. Although the first signs of pregnancy may soon become apparent, a pregnancy test or ultrasound examination is needed to make a definite diagnosis .
The signs of pregnancy can be classified as “possible” and “definite.” .
2.1. Possible signs of pregnancy
Possible signs of pregnancy include the following [6, 7, 8]:
- Absent menstruation – Pregnancy is one possible reason for a missed or late menstrual period. Ovulation in women occurs at some point between two menstrual periods. If an egg is fertilized, hormones prevent menstruation from taking place for the remaining duration of the pregnancy.
- Certain physical symptoms – Symptoms such as nausea, vomiting, or breast tenderness may be caused by pregnancy. However, there can be many other triggers for these as well. Feeling tired and needing to pass urine more frequently are other possible non-specific early signs of pregnancy.
- Darkening of certain skin areas – During pregnancy, the skin surrounding the nipples (the areolae) may become darker. A dark line known as the linea nigra (Latin for “black line”) or linea fusca (Latin for “brown line”) running vertically from the pubic bone to the navel and extending to the breastbone may also appear. Minor discoloration of the skin in the genital area is also possible.
- Palpation findings – Traditionally, manual palpation of the pregnant abdomen was used to elicit various findings. However, since the introduction of ultrasound scans, these findings no longer play an important role.
2.2. Definite signs of pregnancy
Definite signs of pregnancy include the following [6, 9, 10]:
- Positive pregnancy test – In pregnant women, the presence of the hormone β-HCG (human chorionic gonadotropin) can be detected in the blood from day 6 to 9 after fertilization and in the urine from day 14 after fertilization.
- Ultrasound verification – An ultrasound scan, which generates a 2D image using ultrasound waves, can confirm pregnancy by detecting an embryo or its heartbeat.
- Fetal movements – From weeks 18 to 20 of pregnancy, pregnant women may be able to feel the baby move.
It is also good to know that a transvaginal (internal) ultrasound scan can detect an embryo as early as weeks 5 to 6 of pregnancy. From 7 weeks, it can even detect the embryo’s heartbeat .
2.3. How to calculate the due date
The estimated delivery date is calculated using an ultrasound scan or the “Naegele rule.” When the Naegele rule is used, the due date is calculated as follows :
3. Pregnancy milestones
Once a woman discovers she is pregnant, things generally move very quickly. As soon as the pregnancy test result is positive, the calculations begin in an attempt to answer the big question: When exactly will the baby arrive? After all, a new baby is more than just an extra person in a parent’s life. So many other things need to be considered as well. When you push the stroller through the park for the first time, will it be during a scorching hot summer or a crisp cold winter? Will your cousin have returned the baby clothes you lent her by then? Only one thing is certain. The following stages will have to be successfully negotiated before the baby is born.
3.1. Forty weeks in three trimesters
The average pregnancy lasts forty weeks (or around nine months and one week) and is divided into three trimesters. Pregnancy is counted from the first day of the last menstrual period (postmenstrual gestation). In the same way as a child who is five years old has already completed five years of life and is now in his or her sixth year, a woman who has completed five weeks of gestation is now in week 6 of her pregnancy [12, 13].
A doctor would then document the elapsed duration of pregnancy as “5+0 weeks of gestation,” indicating that the pregnant woman has reached the first day of the sixth week of gestation. Babies born before “36+6 weeks of gestation” (that is, before 37 completed weeks) are referred to as premature or preterm babies. On the other hand, babies born after “42+0 weeks of gestation” (that is, after 42 completed weeks) are referred to as post-term babies.
Until the eighth week of gestation, the unborn child is referred to as an embryo. The organs – from brain to heart – start to form during this time. A few dividing cells give rise to the beginnings of body parts that will later perform completely different functions. From the ninth week of gestation, the unborn child is referred to as a fetus. The various organs gradually mature during this phase. The transition from embryo to fetus therefore takes place during the first trimester .
3.2. Physical changes during pregnancy
There are many physical changes that occur in every pregnancy and that are therefore completely normal. Most of these changes start during the first trimester and return to normal after delivery. The following table gives an overview physical changes that can be expected [15 to 22]:
4. Nutrition and exercise during pregnancy: what to look out for
It’s not unusual for a woman’s friends, acquaintances, or colleagues to guess that she is pregnant based on changes in her eating and drinking habits alone. Out of nowhere, she has started steering clear of groups of smokers. On special occasions, she toasts with orange juice instead of her customary drink. And she comes up with the most outlandish excuses for not eating sushi.
By the time her belly starts growing and her willingness to lift heavy boxes on moving day or look after the neighbor’s cat while she is on vacation starts shrinking, there’s no need to send for Sherlock to crack the case. The following section explains what to look out for when it comes to nutrition and exercise during pregnancy.
4.1. The best and worst things to eat and drink during pregnancy
When it comes to nutrition in pregnancy, there are basically three rules of thumb: First, pregnant women need to increase their intake of certain nutrients in order to support the baby’s growth. Second, whatever is harmful to women who are not pregnant is usually even more harmful to pregnant women. Third, pregnant women should avoid eating or drinking anything that could harbor pathogens (disease-causing microorganisms). An overview of nutrition in pregnancy is provided below [23 to 27]:
In general, foods of animal origin such as meat, fish, or eggs should be cooked long enough to kill bacteria before consumption. Fruit and vegetables should be washed thoroughly. Sprouts should generally be avoided during pregnancy. The same applies to certain types of cheese such as brie, feta, and blue cheese. Caffeine-containing beverages should only be consumed in moderation [27, 28].
Pregnant women should discuss individual issues with their health provider at the earliest possible opportunity.
4.2. Weight gain in pregnancy: How much is enough?
While most newborn babies weigh only 3 to 3.5 kg, women gain an average of 10 to 12 kg in the course of the pregnancy. Exactly how much weight a woman gains also depends on how much she weighed before she became pregnant. The following table provides an overview [23, 26]:
4.3. What sports can a woman play while pregnant?
Regular physical activity is proven to be extremely healthy for everyone – regardless of whether they are pregnant or not. In most countries, getting too little exercise is by far a bigger problem than getting too much. The same applies in pregnancy .
For pregnant women, physical activity has positive effects on circulation, stamina, mobility, general pain relief, metabolism, the risk of gestational diabetes, and much more [29, 30].
To prevent injury and avoid harming the unborn baby, a well-balanced mix of low-intensity endurance and strength training is recommended. The former includes walking, aerobic dance, riding a cycle ergometer, jogging (for previously active runners), and swimming. Strength training can consist of resistance band workouts and bodyweight or light dumbbell exercises as well as pelvic floor training [29, 30].
No matter the activity, maximum loads, long distances, overheating, falls, collisions, and a strong build-up of pressure in the abdominal cavity should be avoided. In the case of high-risk pregnancies or an interest in more demanding sports, women should consult their health care provider beforehand [29, 30].
5. Common complaints during pregnancy
The road to childbirth is an evolutionary tour de force. But it is also an impressive feat of strength on the part of the pregnant woman herself – to allow a new life to grow inside her over a period of nine months and carry a living being that reaches a final weight of several kilograms [2, 4].
All the more so since a little extra weight is by no means the only challenge: Problems such as nausea, backache, and skin changes affect most pregnant women. An overview is provided below .
5.1. Gastrointestinal issues
Morning sickness affects around 80% of pregnant women and vomiting occurs in around one- third of pregnancies. These symptoms arise mainly between the eighth and twelfth weeks of gestation but can appear at any stage during the pregnancy. These symptoms are not usually dangerous .
However, very frequent vomiting (more than five times a day) can result in weight loss or even metabolic imbalances and requires prompt medical assessment .
Other common complaints in pregnancy are heartburn and constipation. As with persistent nausea, adjusting the eating habits may help. This could include replacing large meals rich in fats and acids with more frequent, small, fiber-rich meals and drinking plenty of water or tea. Physical activity, sitting up straight while eating, general stress reduction, and relaxation techniques can also help .
Women should discuss persistent or particularly severe symptoms with their health care provider.
5.2. Aches and pains
Various types of pain can arise in pregnancy. For example, around 50% of pregnant women are affected by back pain. This is usually triggered by the additional weight they are carrying and the shift in the body’s center of gravity. Physiotherapy, heat application, and massage can help to relieve mild pain. Women should discuss any aches and pains that become worse despite these measures with their health care provider [18, 19, 32].
Headaches are common in pregnancy, although pregnancy does not cause headaches to become more frequent. In fact, women with migraine may even experience fewer headaches when they are pregnant thanks to hormonal changes .
Many pregnant women also experience stomach aches and other abdominal pains. There are many different reasons for these – some related to pregnancy and others that are completely unrelated. Examples include cramps or pains caused by stretching of the growing uterus, premature labor, or urinary retention due to uterine enlargement. In most cases, abdominal pain is nothing to worry about. However, medical advice should always be sought for persistent or severe pain or pain that occurs in combination with nausea after 20 weeks of pregnancy, fever, diarrhea, or headache [7, 31, 34].
5.3. Skin changes
Various skin changes can occur during pregnancy. These include acne, stretch marks (striae), darkening of the skin, and itching [22, 35].
When acne occurs, it usually appears from the third month of pregnancy on and mainly affects the face. It normally clears up following the birth. Pre-existing acne may get better or worse during pregnancy. Some women experience acne for the first time after the baby is born [22, 33, 35].
Most pregnant women develop reddish stretch marks on their skin. They occur mainly on the abdomen, breasts, or hips as the skin stretches and they fade as pregnancy progresses [22, 35].
Darkening of the skin can also occur in specific areas. This typically affects the skin surrounding the nipples but can also involve the face. A dark line running vertically from the pubic bone to the navel and extending to the breastbone may also appear. Minor discoloration of the skin in the genital area may also occur [22, 35].
Itching is another common symptom experienced in pregnancy. In the vast majority of cases, it is nothing to worry about, even if the cause is unclear. However, medical advice should be sought if the itching is severe or is associated with other symptoms [22, 35].
6. Important things to do before the baby arrives
Eventually, every journey comes to an end and in the case of pregnancy, the biggest hurdle awaits on the home stretch. Childbirth marks the end of one special stage of life and the start of another. It is worth keeping a few things in mind when preparing for this momentous event [36, 37].
A midwife is a treasured companion at a woman’s side during this stage of her life. Unfortunately, midwives are few and far between in Germany. Therefore, it is a good idea to start looking for a midwife for after the child is born as early as possible. The same applies when choosing a setting for the birth. A myriad of options are available and everyone will have their favorite. But regardless of whether a woman wishes to give birth in a hospital, dedicated birthing center, or even at home, arrangements must be made in good time.
New parents often underestimate the demands that having a baby will place on their home. Not only does the arrival of a baby make certain purchases necessary, but most parents lack the time and energy needed to shop or reorganize the home once the baby is already there.
What’s more, each pregnancy has its own peculiarities. Therefore, it is advisable to get as much information and advice as possible during regular medical check-ups. This includes knowing when a cesarean section may be necessary or what pain management and anesthetic procedures are available.
One of the most important jobs on the list is, of course, to pack the hospital bag in advance. You should also consider whose help you will need, who should be contacted, when they should be contacted, and by whom.
And last but not least, don’t panic when the contractions start. You now have on average three to twelve hours to go until your water breaks. And then you will be ready to start a whole new chapter!