Pregnancy occurs when a man’s sperm joins with a woman’s egg, and then the fertilized egg attaches itself to the woman’s uterus. Pregnancy is very common. In fact, according to the Centers for Disease Control and Prevention (CDC), approximately 3.75 million births resulted from pregnancies in the United States in 2019 alone. 

Causes of Pregnancy 

Pregnancy occurs when a man’s sperm fertilizes a woman’s egg, and then the fertilized egg implants in the lining of the woman’s uterus. The typical process is as follows:

  • When a woman ovulates approximately halfway through her menstrual cycle, one of her ovaries releases an egg, which then travels through her fallopian tube toward her uterus. 
  • If a man recently ejaculated into the woman’s vagina during sexual intercourse and the sperm joins with the egg in the fallopian tube, fertilization occurs. 
  • Once this happens, the fertilized egg (zygote) travels through the fallopian tube until it reaches the uterus, where it may attach to the uterine lining—if it does so, this implantation is when pregnancy officially occurs. 

Symptoms of Pregnancy 

The hallmark symptom of pregnancy is a missed period (assuming that the woman is in her childbearing years and has a regular menstrual cycle). Notably, some pregnant women may have light spotting around the time when they would normally have a period—this is known as implantation bleeding, and it occurs when the fertilized egg attaches to the uterus. 

In addition to skipping a period, a pregnant woman may experience: 

  • Swelling and tenderness in her breasts 
  • Nausea 
  • Bloating 
  • Cramping 
  • Frequent urination 
  • Milky white vaginal discharge 
  • Constipation 
  • Fatigue 
  • Moodiness 
  • Food sensitivity (cravings or aversions) 
  • Nasal congestion 

Diagnosing Pregnancy 

Many women use home pregnancy tests to determine whether they’re pregnant. If you’ve received a positive test result, or if your results are negative but you still suspect that you might be pregnant, you should consult with a trained medical provider to receive a more reliable diagnosis. After conducting physical and pelvic examinations and performing additional urine testing, a physician will be able to confirm whether you’re pregnant and, if you are, calculate your due date. 

Treatment for Pregnancy 

Despite how common pregnancy is, it’s still possible for certain complications to occur during gestation (the period of time between when the baby was conceived and when he or she is born). As such, pregnancy treatment is typically aimed at preventing these complications from developing, managing side effects and ensuring a healthy birth.