Pregnancy is the gestation time where one or more offspring develop inside a woman’s womb or uterus. It happens when the sperm of the male sex partner fertilizes with the egg of the female partner, more likely at the time of her ovulation.
The signs of conceiving a child can vary from person to person and from one pregnancy to the next. Hence, it can be difficult to figure out whether the symptoms experienced by women are of pregnancy or pre-menstruation. Well, the only way to confirm pregnancy is to go for a pregnancy test or ultrasound which is best recommended after one week of missing the menstrual period to get the most accurate results.
If looking forward to giving birth to a child, there are a range of early pregnancy symptoms or signs that women can look for. These include missing periods, most often the first sign of pregnancy, morning sickness, sore b-reasts, fatigue, and mood swings, to name a few. However, these symptoms can appear at different times. Some women can immediately feel bodily changes that indicate their pregnancy, while others may go for months without noticing any symptoms at all. The most common early signs of pregnancy are probably caused by a rise in the levels of the pregnancy hormone hCG as well as a surge in female sex hormones. Read on to get more insights on pregnancy signs and symptoms. [2, 3, 4]
When to Expect Early Symptoms of Pregnancy?
It may sound strange, but the first week of pregnancy is based on the date when the last menstrual period happened. Even if a woman is not pregnant, normally, her body considers her menstrual period as the first week of pregnancy. Furthermore, the expected date of delivery of the child is calculated using the starting date of the last menstrual period. This is why women may not experience pregnancy symptoms during the first few weeks of their 40-week pregnancy. 
The 10 Most Common Early Pregnancy Symptoms Before Missed Period:
- Missed periods or unusual vaginal blood spotting/slight bleeding
The first and most obvious sign of pregnancy is the missing period. Likely, this happens 4 weeks after conception. This is when the implantation of a fertilized egg is complete, and the body is making human Chorionic Gonadotropin hormone (hCG) which tells ovaries to stop ovulation (release of eggs every month). It may be harder to notice missing or strange periods if the person typically experiences irregular or late periods. A pregnancy test can help detect levels of this hormone in urine as soon as 8 days after missing the period to show if the person is pregnant or not.
Sometimes, women can get confused and think that slight bleeding or spotting is a sign that a period is on its way, but that’s not so! It’s the implantation bleeding or a normal effect of pregnancy which according to the National Institutes of Health starts after 6 to 12 days of conceiving. It can appear as a brownish discharge or a few tiny drops of red blood which may last for a few days or even several weeks and sometimes throughout the first trimester. [1, 5]
- Raised Basal Body temperature
Basal Body temperature (BBT) is the core body temperature of women who have just woken up in the morning. It is recorded before the woman gets out of her bed. In case of pregnancy, Basal Body Temperature is elevated and does not fall to or below the cover line temperatures on the BBT chart. 
- Frequent urination and incontinence
At the time of pregnancy, there are hormonal fluctuations that prompt a series of events that cause kidneys to process more blood than usual. This results in more fluids in the urinary bladder. Hence, shortly after getting pregnant, women often feel an urge to pee and find themselves rushing to the washroom more frequently or experience accidental leaking of their urine (i.e. urinary incontinence). [3, 5]
- Extreme tiredness or fatigue
As early as the first week of pregnancy, most women find themselves feeling fatigued all of a sudden. This could be because of soaring levels of progesterone hormone. Extreme tiredness can even be caused by morning sickness or constant peeing during the night resulting in disturbed sleep. [1, 2]
- Sensitive or tender breasts, pain in boobs
Sore and tender breasts are usually the first physical signs of pregnancy that occur during weeks 4 and 6. Around week 11, the areola (the area around the nipples) may also grow larger and darker in color. Some women begin to bust out of their bras. These changes in breasts are caused by a rise in female sex hormones as the breasts prepare for breastfeeding. The breast discomfort significantly diminishes during the second trimester as the body gets adjusted to hormonal changes. [4, 5]
- Mood swings
At the onset of pregnancy, mood changes are widespread, partly due to high levels of female sexual hormones that affect the brain’s chemical messengers. Some women during this time would experience heightened emotions i.e. both good and bad, while others might become depressed, irritable, and anxious. 
- Morning sickness, nausea, and vomiting
Usually, around weeks 4 to 6, morning sickness and nausea can develop and be at their peak around week 9 of pregnancy. It can happen anytime throughout the day. 
- Abdominal Bloating and constipation
The hormonal fluctuations during early pregnancy can give a feeling of enlarging belly which is bloating. Women may even experience constipation. All this is due to slower digestion of food caused by the impact of high levels of progesterone. [3, 4]
- Cramping in the abdomen or pelvis
When the embryo attaches itself to the uterine lining i.e. gets implanted, women might experience mild cramping in the lower back, pelvis, or abdomen. 
- Smell sensitivity and food aversions
Smell sensitivity is mostly self-reported by women in their early pregnancy. It may trigger nausea and vomiting and lead to their strong distaste for certain foods. Within 6 to 12 weeks postpartum, smell sensitivity usually returns to normal.